JP4337574B2 - LIGHT EMITTING DEVICE AND METHOD FOR FORMING THE SAME - Google Patents

Description

  The present invention relates to a light-emitting device using a light-emitting element and a fluorescent material, and a method for manufacturing the light-emitting device, and particularly to a light-emitting device that has high emission efficiency, little chromaticity deviation depending on the emission observation direction, excellent optical characteristics, and high reliability. It aims at providing the manufacturing method.

  In recent years, light-emitting devices that combine a light-emitting element and a fluorescent material that emits light having different wavelengths by absorbing at least part of the light from the light-emitting element have been commercialized. For example, in a light emitting device disclosed in Japanese Patent Application Laid-Open No. 11-40848 and Japanese Patent Application Laid-Open No. 2001-15817, a resin layer containing a phosphor has a dispenser around a light emitting element flip-chip mounted on a support substrate. It is arranged and formed by using potting or screen printing.

Japanese Patent Laid-Open No. 11-40848.

Japanese Patent Laid-Open No. 2001-15817.

  However, in the method of forming a wavelength conversion member by potting using a dispenser, when the phosphor-containing liquid resin is supplied and the wavelength conversion member is formed, the surface of the wavelength conversion member becomes a curved surface due to the rheology of the liquid resin. Therefore, a wavelength conversion member having a uniform layer thickness is not formed around the light emitting element. Similarly, in the method of forming the wavelength conversion member by screen printing, the surface of the wavelength conversion member becomes a curved surface on the side surface side of the light emitting element due to the rheology of the liquid resin, and the wavelength conversion member having a uniform layer thickness is not formed. Therefore, the color temperature of the mixed color light of the light from the light emitting element and the light whose wavelength is converted by the phosphor varies depending on each light emission observation direction, and the light emitting device has a low chromaticity shift and high reliability. Can not.

  In the light emitting device in which the electrode of the light emitting element is bonded to the conductive pattern via the bump, the heat radiation from the light emitting element is mainly performed in the direction of the submount via the bump. Fever. In general, phosphors tend to have lower emission luminance as the ambient temperature of the phosphor increases. Therefore, if the phosphor is disposed around the bump, the light emission efficiency of the light emitting device is lowered.

  Therefore, an object of the present invention is to provide a light emitting device having high light emission efficiency and a method for forming the same without causing the color temperature of mixed color light to vary depending on the light emission observation direction.

  In order to achieve the above object, a light emitting device according to the present invention absorbs at least a part of light of a light emitting element in which an electrode is opposed to and bonded to a conductive pattern of a support substrate via a conductive member. And a wavelength conversion member that includes a fluorescent material that emits light having different wavelengths and covers at least a part of the light emitting element, wherein the wavelength conversion member is separated from the conductive member. Features. Further, the wavelength conversion member is at least partially separated from the support substrate. Moreover, it is preferable that the wavelength conversion member is separated from the conductive member or the support substrate via a member containing resin, for example, an underfill material. If comprised in this way, since it can suppress that the brightness | luminance of fluorescent substance falls with the raise of ambient temperature, it can be set as the light-emitting device with high luminous efficiency compared with a prior art. In addition, since the wavelength conversion member having a uniform layer thickness according to the emission observation direction is provided as compared with the prior art, a light emitting device having substantially the same color temperature according to the emission observation direction can be obtained.

  The wavelength conversion member includes a first wavelength conversion member disposed in a side surface direction of the light emitting element and a second wavelength conversion member covering the light emission observation surface side main surface of the light emitting element. Preferably, the first wavelength conversion member has an upper end portion protruding from a plane including the emission observation surface side main surface, and the second wavelength conversion member covers at least a part of the upper end portion. Moreover, it is preferable that the 2nd wavelength conversion member is interposed between the side surface of the said light emitting element, and said 1st wavelength conversion member. This configuration makes it possible to obtain a light emitting device having substantially the same color temperature depending on the light emission observation direction, and the second wavelength conversion member can be firmly fixed and held in the direction of the main light emission surface side of the light emitting element. A highly light-emitting device can be obtained.

  Further, the first wavelength conversion member has an upper end portion protruding from a plane including the main surface on the light emission observation surface side of the second wavelength conversion member, and the second wavelength conversion member is positioned by the upper end portion. Having a sealing member. If comprised in this way, since a sealing member can be fixedly held in the main surface direction of a light emitting element, it can be set as a reliable light-emitting device.

  The fluorescent material includes Al and at least one element selected from Y, Lu, Sc, La, Gd, Tb, Eu, Ga, In and Sm, and at least one element selected from rare earth elements. And at least one element selected from Be, Mg, Ca, Sr, Ba, and Zn, and C, Si, Ge, Sn, Ti, Zr, and It is at least one phosphor selected from phosphors including at least one element selected from Hf and activated by at least one element selected from rare earth elements. As a result, the light emitting device according to the present invention can emit mixed color light of light from the light emitting element and light having different wavelengths in which at least part of the light from the light emitting element is absorbed by the fluorescent material. In addition, the color rendering properties of mixed color light can be improved by combining two or more kinds of phosphors. Furthermore, the center particle size of the particulate fluorescent material contained in the second wavelength conversion member is larger than the center particle size of the particulate fluorescent material contained in the first wavelength conversion member. Thereby, the phosphor distribution in the wavelength conversion member can be made uniform, and the light emitting device having high emission luminance and uniform chromaticity according to the emission observation direction can be obtained.

  Furthermore, in order to achieve the above object, a method for forming a light-emitting device according to the present invention includes a light-emitting element and a phosphor that emits light having different wavelengths by absorbing at least part of light from the light-emitting element. In a method for forming a light emitting device having a wavelength conversion member, a first step of supplying a mixture of a fluorescent material and a binder for fixing the fluorescent material along the outer periphery of the light emitting element, and the mixture A second step of supplying a mixture of a fluorescent material and a binder to the main surface side of the light emitting element, and a third step of curing at least one of the mixture. Features. With this configuration, it is possible to easily form a light emitting device having substantially the same color temperature depending on the light emission observation direction as compared with the prior art.

  Moreover, it is preferable that the mixture supplied by the 1st process is hardened | cured before a 2nd process. If comprised in this way, the material of the 2nd wavelength conversion member can be easily positioned by making the hardened 1st wavelength conversion member into a barrier.

  Further, before the first step, the electrode of the light emitting element is bonded to the conductive pattern of the support substrate via the conductive member. As described above, in the flip-chip mounting, by forming the wavelength conversion member away from the conductive member such as the bump, it is possible to improve the heat dissipation and make the light emitting device with high light emission efficiency as compared with the prior art. Easy to do.

  In the present invention, the center particle size of the particulate fluorescent material in the mixture supplied in the second step is larger than the center particle size of the particulate fluorescent material in the mixture supplied in the first step. Can do. Thereby, it is possible to easily form a light emitting device having high light emission luminance and uniform chromaticity according to the light emission observation direction.

  The light emitting device according to the present invention suppresses a decrease in light emission efficiency due to an increase in ambient temperature, and the color temperature of the mixed color light does not vary depending on the light emission observation direction. Further, according to the forming method of the present invention, it is possible to easily form a light emitting device in which the color temperature or chromaticity of the mixed color light does not differ depending on the emission observation direction.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, the embodiments described below exemplify a light emitting device and a method for forming the same for embodying the technical idea of the present invention, and the present invention does not limit the light emitting device and the method for forming the same to the following. . Further, the size and positional relationship of the members shown in the drawings are exaggerated for clarity of explanation.

  In recent years, there is a light-emitting device that combines a LED chip and a fluorescent material that emits light having different wavelengths by absorbing at least a part of light emitted from the LED chip and obtains mixed color light thereof. For example, in a light emitting device disclosed in Japanese Patent Laid-Open No. 2001-15817, a resin containing a phosphor is formed by screen printing around an LED chip flip-chip mounted on a support substrate called a submount. Here, “flip chip mounting” in this specification refers to a mounting method in which electrodes of a light emitting element are opposed to a conductive pattern of a support substrate through a conductive member called a bump and bonded.

  However, when the wavelength conversion member formed by potting with a dispenser is formed, the surface of the wavelength conversion member becomes a curved surface due to the rheology of the liquid resin, and the layer thickness is uniform around the light emitting element. It does not become a wavelength conversion member. In addition, the wavelength conversion member formed by screen printing has a wavelength conversion member having a substantially uniform layer thickness on the main surface side of the light emitting element, but the wavelength conversion member is formed on the side surface side of the light emitting element by the rheology of the liquid resin. As a result, the surface becomes a curved surface and does not become a wavelength conversion member having a uniform layer thickness. Therefore, the degree of wavelength conversion by the phosphor is different in each orientation of the wavelength conversion member formed around the light emitting element. Therefore, the color temperature of the mixed color light of the light from the light emitting element and the light whose wavelength is converted by the phosphor differs depending on the light emission observation direction, and the light emitting device with little chromaticity deviation cannot be obtained. . Moreover, when forming a wavelength conversion member with the above forming methods, it is not easy to arrange the wavelength conversion member at a desired position on the side end face side of the light emitting element. For example, it is difficult to dispose a phosphor whose luminance decreases as the ambient temperature rises away from a heating element such as a bump or a submount. This is because, if an attempt is made to cover the entire light emitting element with a material having a relatively high viscosity in order to prevent sagging of the heating element, the workability of the entire wavelength conversion member forming process is lowered.

  Therefore, a light emitting element in which an electrode is opposed to and bonded to the conductive pattern of the support substrate through a conductive member, and a fluorescent material that emits light having a different wavelength by absorbing at least part of the light of the light emitting element are included. In a light-emitting device having a wavelength conversion member that covers at least a part of the light-emitting element, the inventors of the present application form the wavelength conversion member in the side surface direction and the main surface direction of the light-emitting element in separate steps, respectively, The problem as described above has been solved by separating the member from at least one of the conductive member and the support substrate.

  That is, as shown in FIG. 1, the light emitting device according to the present invention includes a first wavelength conversion member 104 formed on the side end face side of the light emitting element 103 mounted on the support substrate 101, and the light emitting element 103. And a second wavelength conversion member 105 formed so as to cover the main surface side. The first and second wavelength conversion members 104 and 105 are made of a binder that fixes the phosphor together with the phosphor. In addition, the upper end portion of the first wavelength conversion member 104 is formed such that the height from the main surface of the support substrate 101 is higher than the main surface of the light emitting element 103. Therefore, the upper end portion of the first wavelength conversion member 104 serves as a barrier for the second wavelength conversion member 105, and the second wavelength conversion member 105 is configured not to spill from the main surface side of the light emitting element 103. Such a configuration is particularly effective when a resin having fluidity in an uncured state is used as a binder for the purpose of leveling the emission observation surface to make it a smooth surface. Furthermore, the wavelength conversion member is spaced apart from the bump 102 which is a heat generating element on the side of the light emitting element, and suppresses a decrease in luminance of the heat-sensitive phosphor, thereby providing a light emitting device with high light emission efficiency. Can do.

  Further, in a method for forming a light-emitting device including a light-emitting element and a wavelength conversion member containing a fluorescent material that emits light having a different wavelength by absorbing at least part of light from the light-emitting element, the inventors of the present application. A first step of supplying a mixture of a fluorescent substance and a binder along the outer periphery of the light emitting element, positioning the mixture as a barrier, and binding the fluorescent substance on the main surface side of the light emitting element By forming a light emitting device forming method including a second step of supplying a mixture with an agent and a third step of curing at least one of the mixtures, the above-described problems have been solved.

  That is, the method for forming a light emitting device according to the present invention includes at least the following steps A to C. FIG. 9 is a perspective view schematically showing one embodiment of step A in the method for forming a light emitting device according to the present invention. 10, FIG. 11 and FIG. 12 are a perspective view and a cross-sectional view schematically showing an example of the process B in the method for forming a light emitting device according to the present invention.

  Step A: As shown in FIG. 9, along the outer periphery of the light-emitting element mounted on the support substrate, a mixture of a fluorescent material and a resin material as a binder (hereinafter referred to as “curability”) in the lateral direction of the light-emitting element. "Sometimes referred to as a" composition "). At this time, as shown in FIG. 1 or FIG. 5, the distance a between the side surface of the light emitting element and the outer wall surface of the mixture is from the main surface of the support substrate on the side where the light emitting element is mounted to the upper end of the mixture. Difference (b−h) (thickness of upper end portion) between distance b (height of first wavelength conversion member; b) and distance h from the main surface of the support substrate to the main surface of the light emitting element on the light emission observation surface side Is preferably substantially equal to). In other words, the upper end portion of the mixture forming the first wavelength conversion member protrudes from the emission observation surface side main surface of the translucent substrate 210 by a distance a between the side surface of the light emitting element and the outer wall surface of the mixture. It is preferable to arrange. Thereby, the light emitting element is covered with a wavelength conversion member having a uniform thickness, and a light emitting device with little change in color temperature depending on the light emission observation direction can be obtained.

  The forming method in this step is a method using the dispenser 202 shown in FIG. In this embodiment, a dispenser is used, but a phosphor-containing resin material may be arranged by a metal mask method or a forming method by screen printing used in the following steps. Further, according to the forming method of the present invention, it is possible to easily arrange different types of phosphor-containing resin materials in multiple layers only on the side end face side of the light emitting element.

  Step B: Potting using a dispenser to cover the upper surface of the light emitting element as shown in FIGS. 10 and 11, or arranging a phosphor-containing resin material by screen printing as shown in FIG. Let For example, when using a dispenser, as shown in FIG. 10, after supplying the curable composition 203 to the main surface of the light emitting element 103 along the edge of the curable composition 201 arranged in step A, The curable composition 203 can be supplied spirally and continuously toward the center of the main surface of the light emitting element 103. In addition, as shown in FIG. 11, the curable composition 203 can be spirally and continuously supplied from the vicinity of the center of the light emitting element 103 in the direction of the curable composition 201 arranged in the step A. . At this time, the kind of the fluorescent substance contained can be changed or a diffusing agent can be contained while the curable composition 203 is supplied. Accordingly, it is possible to obtain a light emitting device with high light emission efficiency in consideration of absorption of light emission between phosphors of different types and light distribution characteristics of the light emitting device.

  In this step, the mixture disposed in step A or the first wavelength conversion member on which it is cured serves as a barrier that prevents the flow of the mixture supplied in this step, and the curable composition 203 supplied It is easy to perform positioning. That is, the difference between the distance b from the main surface of the support substrate on the side where the light emitting element is mounted to the upper end of the mixture and the distance h from the main surface of the support substrate to the main surface of the light emitting element on the light emission observation surface side (Bh) is the height of the barrier, and is the thickness c of the curable composition 203 supplied in this step. The thickness c can be made equal to the distance a between the side surface of the light emitting element and the outer wall surface of the mixture. As a result, the light emitting element is covered with the first and second wavelength conversion members 104 and 105 having a uniform thickness, and a light emitting device with little change in color temperature depending on the light emission observation direction can be obtained. Moreover, the quantity of the fluorescent substance contained can be enlarged or made smaller than the mixture arrange | positioned at the said process A. FIG.

  Step C: After obtaining a smooth surface of the phosphor-containing mixture by allowing it to stand for a predetermined time, a first wavelength conversion member that covers the side end portion side of the light-emitting element by curing the mixture, And the 2nd wavelength conversion member which coat | covers the main surface side of a light emitting element is formed. It is preferable to supply a resin as an underfill material to a gap generated between the light emitting element mounted on the flip chip and the support substrate. With such a configuration, the heat dissipation of the light emitting device is improved, and the thermal expansion and mechanical stress between the light emitting element and the support substrate can be relieved, so that the reliability of the light emitting device can be improved. . In addition, the wavelength conversion member and the bump or submount can be separated from each other by disposing the underfill material via the wavelength conversion member and the bump or submount.

  In addition, the mixture which forms a 1st wavelength conversion member and a 2nd wavelength conversion member may be hardened separately, and may be hardened simultaneously. That is, after the material of the first wavelength conversion member is cured, a phosphor-containing resin may be disposed on the main surface side of the light emitting element. By separately curing in this way, positioning for forming the second wavelength conversion member can be easily performed. Moreover, the interface of a 1st wavelength conversion member and a 2nd wavelength conversion member arises by making it harden | cure separately. Hereinafter, each structure of this form is explained in full detail.

[Wavelength conversion member]
The wavelength conversion member in the present embodiment is a member that is disposed around the light emitting element and can emit light including different wavelengths by absorbing light from the light emitting element. The wavelength conversion member includes a fluorescent material such as an organic phosphor or an inorganic phosphor described below, a diffusing agent that scatters light from the light emitting element in the direction of the light emission observation surface, and a wavelength emitted from the light emitting element. A colorant or a pigment having a filter effect for cutting off the part can also be contained. Here, the mixing ratio and type of the diffusing agent, the binder for fixing the fluorescent material and the fluorescent material contained in the first wavelength converting member and the second wavelength converting member need not be the same. That is, the first wavelength conversion member and the second wavelength conversion member may contain different types of diffusing agents and fluorescent materials at different mixing ratios. Moreover, the first wavelength conversion member and the second wavelength conversion member can be formed in a multilayer structure by being formed adjacent to each other. For example, as shown in FIG. 3, the first wavelength conversion members 104a and 104b and the second wavelength conversion members 105a and 105b may be used. Further, when the multilayer structure is used as described above, the type, amount and particle size of the binder, the fluorescent material and the diffusing agent contained therein can be changed for each layer, and the refractive index can be changed. Hereinafter, the first wavelength conversion member formed on the side end surface side of the light emitting element and the second wavelength conversion member arranged in the main surface direction of the light emitting element will be described in detail.

(First wavelength conversion member 104)
As a material for forming the first wavelength conversion member in the present embodiment, a resin having a relatively high thixotropy that hardly causes sagging is used as a binder. By using a material with high thixotropy in this way, it is difficult to enter the gap between the light emitting element and the support substrate, and the conductive member can be prevented from sagging. For example, a resin having the same composition as the sealing resin (however, the thixotropy is different) can be used. The range of thixotropy is adjusted so that a uniform height can be easily formed with good workability to such an extent that sagging and lack of height do not occur.

  The height of the first wavelength conversion member is formed to be substantially the same as the height of the light emitting element mounted on the support substrate from the support substrate, but the second wavelength conversion member may be slightly lower than this. There is no particular problem as long as the forming material is high enough to be positioned on the main surface side of the light emitting element.

  When the resin material for forming the first wavelength conversion member is a thermosetting resin, it is preferable that the viscosity does not decrease due to heat at the time of heat curing. As such a material, a core-shell type fine particle in which ultrafine silica powder or fine rubber particles are wrapped in a resin for sealing is added in a range of 0.1 to 10 parts per 100 parts of the resin component. Can be mentioned.

  As a method for mounting the light emitting element on the support substrate, there is a method in which the electrode of the light emitting element is opposed to the bump arranged on the conductive pattern of the support substrate and bonded by applying a load, heat and ultrasonic waves. Here, in this embodiment, when flip chip mounting is performed, as described above, if the material of the first wavelength conversion member is a thixotropic material, it is difficult for the material to enter between the light emitting element and the support substrate. A gap is generated between the light emitting element and the support substrate. Therefore, it is preferable to inject an underfill material 206 between the light emitting element and the support substrate before disposing the material forming the first wavelength conversion member. As shown in FIG. 4, by disposing the thixotropic underfill material 206, the first wavelength conversion member 104 and the bump 102, which is a heating element, can be disposed apart from each other. Incidentally, the heat generated by the light emitting element 103 is radiated toward the support substrate 101 through the bumps 102. Therefore, the support substrate 101 becomes a heating element like the bumps 102. In the present embodiment, the first wavelength conversion member 104 can also be disposed separately from the support substrate 101 that is a heating element via the underfill material 206. By disposing the underfill material at a distance from the heating element in this way, it is possible to suppress a decrease in luminance of the fluorescent material contained in the first wavelength conversion member and to obtain a light emitting device with high luminous efficiency.

  The underfill material 206 is disposed on the support substrate before flip-chip mounting, or is injected between the light-emitting element and the support substrate after flip-chip mounting and before disposing the material forming the first wavelength conversion member, Heat cured. The underfill material is, for example, a thermosetting resin such as a silicone resin or an epoxy resin. In order to improve the thermal conductivity of the underfill or to relieve the thermal stress of the underfill, aluminum nitride, silicon oxide, aluminum oxide, a composite mixture thereof, or the like may be further mixed into the resin. The amount of underfill is an amount that can fill a gap formed between the positive and negative electrodes of the light emitting element and the submount.

(Second wavelength conversion member 105)
After forming the first wavelength conversion member, or before arranging the material for forming the first wavelength conversion member and before curing, the outer edge is the first wavelength conversion member so as to cover the main surface side of the light emitting element. The material for forming the second wavelength conversion member is arranged as described above. Forming methods such as stencil printing, screen printing, and potting are applied to the arrangement of the material forming the second wavelength conversion member. The material of the second wavelength conversion member arranged by such a forming method has fluidity until curing, but the flow in the direction of the side end face of the light emitting element is the first formed first. It is blocked by the wavelength conversion member or the material before curing. Therefore, the material of the second wavelength conversion member retains the shape at the time when the material is disposed in combination with the rheology. Further, since the surface of the second wavelength conversion member is still fluid until it is cured, the surface is naturally flat and smoothness can be obtained.

  After the light emitting element is coated with the material of the second wavelength conversion member, the material is cured, and when the first wavelength conversion member is uncured, the material is heated and cured together with the first wavelength conversion member. Furthermore, as another embodiment of the present invention, a wavelength conversion member having a multilayer structure so that the types of phosphors are different in each layer is provided as a striped or concentric wavelength conversion member so as to cover the upper surface of the light emitting element. be able to. Accordingly, it is possible to obtain a light emitting device with high light emission efficiency in consideration of absorption of light emission between phosphors of different types and light distribution characteristics of the light emitting device.

  Moreover, it is preferable that the first wavelength conversion member 104 has an upper end portion that protrudes from a plane including the light emission observation surface side main surface, and the second wavelength conversion member 105 covers at least a part of the upper end portion. . By configuring in this way, the second wavelength conversion member 105 is fixedly held on the emission observation surface side main surface and does not move laterally, so that a highly reliable light emitting device can be obtained.

  The second wavelength conversion member 105 is preferably interposed between the side surface of the light emitting element and the first wavelength conversion member 104. With this configuration, the second wavelength conversion member 105 is firmly fixed and held on the main surface of the light emitting element on the light emission observation surface side, and does not fall off. Therefore, a highly reliable light emitting device can be obtained. . Furthermore, the type of the phosphor contained is changed by the first wavelength conversion member 104, the side surface of the light emitting element, and the second wavelength conversion member 105 interposed between the first wavelength conversion member 104. Thus, a light emitting device having desired optical characteristics can be obtained.

  The material constituting the first and second wavelength conversion members described above and the binder for fixing the phosphor is a thermosetting resin excellent in light resistance and translucency, for example, epoxy resin, acrylic An organic substance such as a resin, an imide resin, or a silicon resin, a translucent inorganic member obtained by a sol-gel method using a metal alkoxide as a starting material, or an inorganic substance such as glass can be selected. In addition, aluminum oxide, barium oxide, barium titanate, silicon oxide, or the like can be contained in the wavelength conversion member for the purpose of diffusing light from the light emitting element. Similarly, various colorants can be added in order to have a filter effect of cutting unnecessary wavelengths from extraneous light and light emitting elements. Moreover, various fillers that relieve internal stress of the sealing resin can also be contained.

  Both the first wavelength conversion member and the second wavelength conversion member can be a uniform layer having a layer thickness of about 20 μm to 100 μm. Further, the amount of the phosphor contained in the first wavelength conversion member can be made smaller than the amount of the phosphor contained in the second phosphor. As a result, a light emitting device with a small color temperature difference depending on the light emission observation direction can be obtained.

[Fluorescent substance 106]
In the present invention, in the semiconductor element structure of the light emitting element, a sealing member that covers the light emitting element, a die bond material that fixes the light emitting element to a support or a lead electrode, a resin layer provided between the light emitting element and the support substrate, and Various fluorescent materials such as an inorganic phosphor and an organic phosphor can be arranged in and / or around each component such as a support base such as a package. In particular, the fluorescent material combined with the sealing member is provided in a sheet shape so as to cover the light emission observation surface side surface of the sealing member, and is separated from the light emission observation surface side surface of the sealing member or the light emitting element. It can also be provided at a position as a layer containing a phosphor, a sheet containing a phosphor or a filter. By separating them in this manner, it is possible to suppress a decrease in luminance of the phosphor due to heat around the light emitting element and to obtain a light emitting device with high luminous efficiency.

  The phosphor that can be used in the present invention absorbs part of visible light and ultraviolet light emitted from the light emitting element, and emits light having a wavelength different from the wavelength of the absorbed light. In particular, the phosphor used in this embodiment refers to a phosphor that emits a wavelength-converted light that is excited by at least light emitted from the light-emitting element, and constitutes a wavelength conversion member together with a binder that fixes the phosphor. To do.

  When the light from the light emitting element and the light emitted from the phosphor are in a complementary color relationship or the like, white mixed color light can be emitted by mixing each light. Specifically, the light emitted from the light emitting element and the phosphor light excited and emitted thereby correspond to the three primary colors of light (red, green, and blue), or the blue light emitted from the light emitting element. And yellow light of a phosphor that is excited to emit light.

  The emission color of the light-emitting device can be adjusted in various ways such as the ratio between the phosphor and various members such as various resins and glass that act as a binder for the phosphor, the specific gravity of the phosphor, the amount and shape of the phosphor, and By selecting the light emission wavelength of the light emitting element, it is possible to change the color temperature of the mixed color light and provide an arbitrary white color tone such as light in the light bulb color region. It is preferable that the light from the light emitting element and the light from the phosphor efficiently pass through the mold member outside the light emitting device.

  Since such a phosphor settles under its own weight in the gas phase or liquid phase, it is dispersed and uniformly released in the gas phase or liquid phase, and in particular in the liquid phase, the suspension is allowed to stand, A layer having a phosphor with higher uniformity can be formed. Furthermore, a desired phosphor amount can be formed by repeating a plurality of times as desired.

  Two or more kinds of phosphors formed as described above may be present in a single-layer wavelength conversion member on the surface of the light-emitting device, or one or two of each of the two-layer wavelength conversion member. There may be more than one type. In this way, white light can be obtained by mixing colors from different types of phosphors. In this case, it is preferable that the average particle diameters and shapes of the phosphors are similar in order to better mix the light emitted from the phosphors and reduce color unevenness.

  Here, the central particle diameter of the phosphor in the present specification is a value obtained by a volume-based particle size distribution curve, and the volume-based particle size distribution curve is obtained by measuring the particle size distribution of the phosphor by a laser diffraction / scattering method. It is obtained. Specifically, in an environment where the temperature is 25 ° C. and the humidity is 70%, the phosphor is dispersed in a sodium hexametaphosphate aqueous solution having a concentration of 0.05%, and a laser diffraction particle size distribution analyzer (SALD-2000A) It was obtained by measuring in a particle size range of 0.03 μm to 700 μm.

  The phosphors used in the present embodiment are yttrium / aluminum / garnet phosphors and aluminum / garnet phosphors typified by lutetium / aluminum / garnet phosphors and fluorescence capable of emitting red light. In combination, it is also possible to use a combination of a phosphor, particularly a nitride-based phosphor. These YAG phosphors and nitride phosphors may be mixed and contained in the wavelength conversion member, or may be separately contained in the wavelength conversion member composed of a plurality of layers. Hereinafter, each phosphor will be described in detail.

(Aluminum / garnet phosphor)
The aluminum garnet phosphor used in the present embodiment includes Al and at least one element selected from Y, Lu, Sc, La, Gd, Tb, Eu, and Sm, and Ga and In. It is a phosphor that contains one selected element and is activated by at least one element selected from rare earth elements, and is a phosphor that emits light when excited by visible light or ultraviolet light emitted from an LED chip. . For example, Tb _2.95 Ce _0.05 Al ₅ O ₁₂ , Y _2.90 Ce _0.05 Tb _0.05 Al ₅ O ₁₂ , Y _2.94 Ce _0.05 Pr _0.01 Al ₅ O ₁₂ , Y _2.90 Ce _0.05 Pr _0.05 Al ₅ O _{12 and the} like.

In particular, in the present embodiment, two or more types of yttrium / aluminum oxide phosphors (yttrium / aluminum / garnet phosphors (hereinafter referred to as “YAG phosphors”) containing Y and activated by Ce or Pr and having different compositions. Called "body"))). In particular, at the time of high luminance and long-term use _{(Re 1-x Sm x)} 3 (Al 1-y Ga y) 5 O 12: Ce (0 ≦ x <1,0 ≦ y ≦ 1, where, Re Is at least one element selected from the group consisting of Y, Gd, and La).

_{(Re 1-x Sm x)} 3 (Al 1-y Ga y) 5 O 12: Ce phosphor, for garnet structure, heat, resistant to light and moisture, the peak of the excitation spectrum can be like in the vicinity of 470nm Can do. In addition, the emission peak is in the vicinity of 530 nm, and a broad emission spectrum that extends to 720 nm can be provided.

In the light emitting device of the present invention, the phosphor may be a mixture of two or more phosphors. That is, speaking the YAG fluorescent material described above, Al, Ga, Y, the content of La and Gd and Sm are two or more kinds of _{(Re 1-x Sm x)} 3 (Al 1-y Ga y) 5 O ₁₂ : Ce phosphors can be mixed to increase RGB wavelength components. At present, there are variations in the emission wavelength of the semiconductor light emitting device, so that two or more kinds of phosphors can be mixed and adjusted to obtain a desired white mixed color light or the like. Specifically, by adjusting the amount of phosphors having different chromaticity points in accordance with the emission wavelength of the light emitting element, the arbitrary points on the chromaticity diagram connected between the phosphors and the light emitting element are caused to emit light. be able to.

  Blue light emitted from a light emitting device using a nitride compound semiconductor in the light emitting layer, green light emitted from a phosphor whose body color is yellow to absorb blue light, red light, When mixed color display is performed, a desired white light emission color display can be performed. In order to cause this color mixture, the light emitting device can contain phosphor powder and bulk in various resins such as epoxy resin, acrylic resin or silicone resin, and translucent inorganic materials such as silicon oxide and aluminum oxide. Such phosphors can be used in various ways depending on the application, such as dot-like and layer-like ones that are formed thin enough to transmit light from the light-emitting element. By adjusting the ratio, coating, and filling amount of the phosphor and the translucent inorganic substance and selecting the emission wavelength of the light emitting element, it is possible to provide an arbitrary color tone such as a light bulb color including white.

  Further, by arranging two or more kinds of phosphors in order with respect to the incident light from the light emitting element, a light emitting device capable of emitting light efficiently can be obtained. That is, on a light emitting element having a reflective member, a color conversion member containing a phosphor that has an absorption wavelength on the long wavelength side and can emit light at a long wavelength, and an absorption wavelength on the longer wavelength side that has a longer wavelength. The reflected light can be used effectively by laminating a color conversion member capable of emitting light at a wavelength.

When a YAG phosphor is used, sufficient light resistance with high efficiency even when it is placed in contact with or close to a light emitting element having an irradiance of (Ee) = 0.1 W · cm ^{−2 to} 1000 W · cm ⁻² The light emitting device can be made to have the property.

  The cerium-activated YAG-based phosphor used in this embodiment and capable of emitting green light has a garnet structure and is resistant to heat, light, and moisture, and the peak wavelength of the excitation absorption spectrum is in the vicinity of 420 nm to 470 nm. Can be made. Also, the emission peak wavelength λp is near 510 nm, and has a broad emission spectrum that extends to the vicinity of 700 nm. On the other hand, the YAG phosphor that emits red light, which is an yttrium-aluminum oxide phosphor activated by cerium, has a garnet structure, is resistant to heat, light and moisture, and has a peak wavelength of 420 nm in the excitation absorption spectrum. To about 470 nm. Further, the emission peak wavelength λp is in the vicinity of 600 nm, and has a broad emission spectrum that extends to the vicinity of 750 nm.

  Of the composition of YAG phosphors with a garnet structure, the emission spectrum is shifted to the short wavelength side by substituting part of Al with Ga, and part of Y of the composition is replaced with Gd and / or La. By doing so, the emission spectrum shifts to the long wavelength side. In this way, it is possible to continuously adjust the emission color by changing the composition. Therefore, an ideal condition for converting white light emission by using blue light emission of the nitride semiconductor is provided such that the intensity on the long wavelength side is continuously changed by the composition ratio of Gd. If the substitution of Y is less than 20%, the green component is large and the red component is small, and if it is 80% or more, the redness component is increased but the luminance is drastically decreased. Similarly, the excitation absorption spectrum is shifted to the short wavelength side by substituting part of Al with Ga in the composition of the YAG phosphor having a garnet structure. By substituting a part of Gd and / or La, the excitation absorption spectrum is shifted to the longer wavelength side. The peak wavelength of the excitation absorption spectrum of the YAG phosphor is preferably on the shorter wavelength side than the peak wavelength of the emission spectrum of the light emitting element. With this configuration, when the current input to the light emitting element is increased, the peak wavelength of the excitation absorption spectrum substantially matches the peak wavelength of the emission spectrum of the light emitting element, so that the excitation efficiency of the phosphor is not reduced. Thus, a light emitting device in which the occurrence of chromaticity deviation is suppressed can be formed.

  The aluminum garnet phosphor can be manufactured by the following method. First, phosphors use oxides or compounds that easily become oxides at high temperatures as raw materials for Y, Gd, Ce, La, Al, Sm, Pr, Tb and Ga, and they are added in a stoichiometric ratio. Mix thoroughly to obtain the raw material. Or a coprecipitated oxide obtained by calcining a solution obtained by coprecipitation of oxalic acid with a solution obtained by dissolving a rare earth element of Y, Gd, Ce, La, Sm, Pr, and Tb in an acid at a stoichiometric ratio with acid; Aluminum and gallium oxide are mixed to obtain a mixed raw material. An appropriate amount of fluoride such as ammonium fluoride is mixed with this as a flux and packed in a crucible, fired in air at a temperature range of 1350 to 1450 ° C. for 2 to 5 hours to obtain a fired product, and then the fired product in water. It can be obtained by ball milling, washing, separating, drying and finally passing through a sieve. Further, in the method for manufacturing a phosphor according to another embodiment, a first firing step in which a mixture composed of a mixture of phosphor materials and a flux is mixed in the atmosphere or in a weak reducing atmosphere, and in a reducing atmosphere. It is preferable to perform the baking in two stages, which includes the second baking step performed in step (b). Here, the weak reducing atmosphere refers to a weak reducing atmosphere set to include at least the amount of oxygen necessary in the reaction process of forming a desired phosphor from the mixed raw material. By performing the first firing step until the formation of the phosphor structure is completed, blackening of the phosphor can be prevented and a decrease in light absorption efficiency can be prevented. In addition, the reducing atmosphere in the second firing step refers to a reducing atmosphere stronger than the weak reducing atmosphere. By firing in two stages in this way, a phosphor with high absorption efficiency at the excitation wavelength can be obtained. Therefore, when a light emitting device is formed with the phosphor thus formed, the amount of the phosphor necessary for obtaining a desired color tone can be reduced, and a light emitting device with high light extraction efficiency can be formed. Can do.

Aluminum and garnet phosphors activated with two or more types of cerium having different compositions may be mixed or used independently. When the phosphors are arranged independently, it is preferable to arrange the phosphors in the order of the phosphor that easily absorbs and emits light from the light emitting element on the shorter wavelength side, and the phosphor that easily absorbs and emits light on the longer wavelength side. This makes it possible to efficiently absorb and emit light.
(Lutetium / Aluminum / Garnet phosphor)
The lutetium / aluminum / garnet phosphor is a general formula (Lu _1-ab R _a M _b ) ₃ (Al _1-c Ga _c ) ₅ O ₁₂ (provided that R is at least one element in which Ce is essential). The above rare earth elements, M is at least one element selected from Sc, Y, La, and Gd, and 0.0001 ≦ a ≦ 0.5, 0 ≦ b ≦ 0.5, 0.0001 ≦ a + b <1, 0 ≦ c ≦ 0.8.) For example, the composition formula is (Lu _0.99 Ce _0.01 ) ₃ Al ₅ O ₁₂ , (Lu _0.90 Ce _0.10 ) ₃ Al ₅ O ₁₂ , (Lu _0.99 Ce _0.01 ) ₃ (Al a phosphor represented by _0.5 Ga _{0.5) 5} O _12.

  The lutetium / aluminum / garnet phosphor (hereinafter sometimes referred to as “LAG phosphor”) is obtained as follows. As a phosphor raw material, a lutetium compound, a rare earth element R compound, a rare earth element M compound, an aluminum compound, and a gallium compound are used, and each compound is weighed and mixed so as to have the ratio of the above general formula, or these are mixed. Flux is added to the phosphor material and mixed to obtain a material mixture. After filling this raw material mixture into a crucible, it is fired at 1200 to 1600 ° C. in a reducing atmosphere, and after cooling, the phosphor of the present invention represented by the above general formula is obtained by dispersion treatment.

  As the phosphor raw material, an oxide or a compound such as a carbonate or hydroxide that becomes an oxide by thermal decomposition is preferably used. Moreover, the coprecipitate which contains all or one part of each metal element which comprises a fluorescent substance can also be used as a fluorescent substance raw material. For example, when an aqueous solution such as alkali or carbonate is added to an aqueous solution containing these elements, a coprecipitate can be obtained, which can be used after being dried or thermally decomposed. Moreover, as a flux, a fluoride, a borate, etc. are preferable, and it adds in 0.01-1.0 weight part with respect to 100 weight part of fluorescent substance raw materials. The firing atmosphere is preferably a reducing atmosphere in which the activator cerium is not oxidized. A mixed gas atmosphere of hydrogen and nitrogen having a hydrogen concentration of 3.0% by volume or less is more preferable. The firing temperature is preferably 1200 to 1600 ° C., and a phosphor having a target center particle diameter can be obtained. More preferably, it is 1300-1500 degreeC.

  In the above general formula, R is an activator and is at least one or more rare earth elements essential for Ce, specifically, Ce, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lr. R may be Ce alone, but may contain Ce and at least one element selected from rare earth elements other than Ce. This is because rare earth elements other than Ce act as coactivators. Here, it is preferable that Ce contains 70 mol% or more of Ce with respect to the total amount of R. The a value (R amount) is preferably 0.0001 ≦ a ≦ 0.5. If the value is less than 0.0001, the light emission luminance is lowered, and if it exceeds 0.5, the light emission luminance is lowered by concentration quenching. More preferably, 0.001 ≦ a ≦ 0.4, and still more preferably 0.005 ≦ a ≦ 0.2. The b value (M amount) is preferably 0 ≦ b ≦ 0.5, more preferably 0 ≦ b ≦ 0.4, and still more preferably 0 ≦ b ≦ 0.3. For example, when M is Y and the b value exceeds 0.5, the emission luminance due to excitation of long-wavelength ultraviolet light to short-wavelength visible light, particularly 360 to 410 nm is extremely lowered. The c value (Ga content) is preferably 0 ≦ c ≦ 0.8, more preferably 0 ≦ c ≦ 0.5, and still more preferably 0 ≦ c ≦ 0.3. When the c value exceeds 0.8, the emission wavelength shifts to a short wavelength, and the emission luminance decreases.

  The center particle size of the LAG phosphor is preferably in the range of 1 to 100 μm, more preferably in the range of 5 to 50 μm, and still more preferably in the range of 5 to 15 μm. Phosphors smaller than 1 μm tend to form aggregates. On the other hand, a phosphor having a particle size in the range of 5 to 50 μm has high light absorptivity and conversion efficiency, and easily forms a wavelength conversion member. As described above, the mass productivity of the light-emitting device is improved by including a phosphor having a large particle diameter and having optically excellent characteristics. Moreover, it is preferable that the fluorescent substance which has the said center particle size value is contained frequently, and 20%-50% of frequency values are preferable. By using a phosphor having a small variation in particle size in this way, a light emitting device having a favorable color tone with more suppressed color unevenness can be obtained.

  Since the lutetium / aluminum / garnet phosphor is efficiently excited and emitted by ultraviolet rays or visible light in a wavelength region of 300 nm to 550 nm, it can be effectively used as a phosphor contained in the wavelength conversion member. Furthermore, by using a plurality of types of LAG phosphors having different composition formulas or LAG phosphors together with other phosphors, the emission color of the light emitting device can be variously changed. A conventional light emitting device that emits white light by mixing blue light emitted from a semiconductor light emitting element and light emitted from a phosphor emitting yellow light by absorbing the light emitted from the light emitting element. Since part of the light is used through transmission, there is an advantage that the structure itself can be simplified and the output can be easily improved. On the other hand, since the light emitting device emits light by mixing two colors, the color rendering properties are not sufficient, and improvement is required. Therefore, a light emitting device that emits white color mixed light using a LAG phosphor can improve its color rendering as compared with a conventional light emitting device. In addition, since the LAG phosphor has excellent temperature characteristics as compared with the YAG phosphor, a light emitting device with little deterioration and color shift can be obtained.

(Nitride phosphor)
The phosphor used in the present invention contains N and at least one element selected from Be, Mg, Ca, Sr, Ba, and Zn, and C, Si, Ge, Sn, Ti, Zr, and A nitride-based phosphor containing at least one element selected from Hf and activated by at least one element selected from rare earth elements can also be used. The nitride-based phosphor used in the present embodiment refers to a phosphor that emits light when excited by absorbing visible light, ultraviolet light, and light emitted from the YAG-based phosphor emitted from the LED chip. For example, Ca—Ge—N: Eu, Z system, Sr—Ge—N: Eu, Z system, Sr—Ca—Ge—N: Eu, Z system, Ca—Ge—O—N: Eu, Z system, Sr—Ge—O—N: Eu, Z system, Sr—Ca—Ge—ON: Eu, Z system, Ba—Si—N: Eu, Z system, Sr—Ba—Si—N: Eu, Z Type, Ba-Si-ON: Eu, Z type, Sr-Ba-Si-ON: Eu, Z type, Ca-Si-CN: Eu, Z type, Sr-Si-CN : Eu, Z system, Sr-Ca-Si-CN: Eu, Z system, Ca-Si-C-O-N: Eu, Z system, Sr-Si-C-O-N: Eu, Z system Sr—Ca—Si—C—O—N: Eu, Z series, Mg—Si—N: Eu, Z series, Mg—Ca—Sr—Si—N: Eu, Z series, Sr—Mg—Si— N: Eu, Z-based, Mg-Si-O- : Eu, Z series, Mg-Ca-Sr-Si-ON: Eu, Z series, Sr-Mg-Si-ON: Eu, Z series, Ca-Zn-Si-CN: Eu, Z-based, Sr-Zn-Si-CN: Eu, Z-based, Sr-Ca-Zn-Si-CN: Eu, Z-based, Ca-Zn-Si-CN- Eu: Z System, Sr—Zn—Si—C—O—N: Eu, Z system, Sr—Ca—Zn—Si—C—O—N: Eu, Z system, Mg—Zn—Si—N: Eu, Z system Mg-Ca-Zn-Sr-Si-N: Eu, Z system, Sr-Zn-Mg-Si-N: Eu, Z system, Mg-Zn-Si-O-N: Eu, Z system, Mg- Ca-Zn-Sr-Si-ON: Eu, Z system, Sr-Mg-Zn-Si-ON: Eu, Z system, Ca-Zn-Si-Sn-CN: Eu, Z system , Sr-Zn-Si-S -CN: Eu, Z system, Sr-Ca-Zn-Si-Sn-CN: Eu, Z system, Ca-Zn-Si-Sn-C-O-N: Eu, Z system, Sr- Zn—Si—Sn—C—O—N: Eu, Z series, Sr—Ca—Zn—Si—Sn—C—O—N: Eu, Z series, Mg—Zn—Si—Sn—N: Eu, Z-based, Mg-Ca-Zn-Sr-Si-Sn-N: Eu, Z-based, Sr-Zn-Mg-Si-Sn-N: Eu, Z-based, Mg-Zn-Si-Sn-O-N : Eu, Z series, Mg-Ca-Zn-Sr-Si-Sn-ON: Eu, Z series, Sr-Mg-Zn-Si-Sn-ON: Various combinations such as Eu, Z series A phosphor can be manufactured. Z that indicates a rare earth element preferably contains at least one of Y, La, Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er, and Lu, but Sc, Sm , Tm, Yb may be contained. These rare earth elements are mixed in the raw material in the form of oxides, imides, amides, etc. in addition to simple substances. Rare earth elements mainly have a stable trivalent electron configuration, while Yb, Sm, etc. have a divalent configuration, and Ce, Pr, Tb, etc. have a tetravalent electron configuration. When the rare earth element of the oxide is used, the involvement of oxygen affects the light emission characteristics of the phosphor. In other words, the emission luminance may be reduced by containing oxygen. On the other hand, there are also advantages such as shortening the afterglow. However, when Mn is used, the particle size can be increased and the emission luminance can be improved.

For example, La is used as a coactivator. Since lanthanum oxide (La ₂ O ₃ ) is a white crystal and is quickly replaced with carbonate when left in the air, it is stored in an inert gas atmosphere.
For example, Pr is used as a coactivator. Praseodymium oxide (Pr ₆ O ₁₁ ) is a non-stoichiometric oxide, unlike ordinary rare earth oxide Z ₂ O _3, and burns praseodymium oxalate, hydroxide, carbonate, etc. in the air 800 When heated to 0 ° C., it is obtained as a black powder having a composition of Pr ₆ O ₁₁ . Pr ₆ O ₁₁ is a starting material for synthesizing a praseodymium compound, and a high-purity one is also commercially available.

In particular, the phosphor according to the present invention includes Sr—Ca—Si—N: Eu, Ca—Si—N: Eu, Sr—Si—N: Eu, and Sr—Ca—Si—O—N with Mn added: Eu, Ca-Si-ON: Eu, Sr-Si-ON: Eu-based silicon nitride. The basic constituent elements of this phosphor are represented by the general formula L _X Si _Y N _{(2 / 3X + 4 / 3Y)} : Eu or L _X Si _Y O _Z N _{(2 / 3X + 4 / 3Y-2 / 3Z)} : Eu (L is Sr, Ca, or any one of Sr and Ca.) In the general formula, X and Y are preferably X = 2, Y = 5, or X = 1, Y = 7, but any can be used. Specifically, the basic constituent elements, Mn is added _{(Sr X Ca 1-X)} 2 Si 5 N 8: Eu, Sr 2 Si 5 N 8: Eu, Ca 2 Si 5 N 8: Eu, Sr _{X Ca 1-X Si 7 N} 10: Eu, SrSi 7 N 10: Eu, CaSi 7 N 10: it is preferable to use a phosphor represented by Eu, during the composition of the phosphor, Mg, At least one selected from the group consisting of Sr, Ca, Ba, Zn, B, Al, Cu, Mn, Cr and Ni may be contained. However, the present invention is not limited to this embodiment and examples.
L is any one of Sr, Ca, Sr and Ca. The mixing ratio of Sr and Ca can be changed as desired.
By using Si for the composition of the phosphor, it is possible to provide an inexpensive phosphor with good crystallinity.

Europium Eu, which is a rare earth element, is used for the emission center. Europium mainly has bivalent and trivalent energy levels. The phosphor of the present invention uses Eu ²⁺ as an activator with respect to the base alkaline earth metal silicon nitride. Eu ²⁺ is easily oxidized and is commercially available with a trivalent Eu ₂ O ₃ composition. However, in commercially available Eu ₂ O ₃ , O is greatly involved and it is difficult to obtain a good phosphor. Therefore, it is preferable to use a material obtained by removing O from Eu ₂ O ₃ out of the system. For example, it is preferable to use europium alone or europium nitride. However, this is not the case when Mn is added.

_{Sr 2 Si 5 N 8: Eu} , Pr, Ba 2 Si 5 N 8: Eu, Pr, Mg 2 Si 5 N 8: Eu, Pr, Zn 2 Si 5 N 8: Eu, Pr, SrSi 7 N 10: Eu _{, Pr, BaSi 7 N 10:} Eu, Ce, MgSi 7 N 10: Eu, Ce, ZnSi 7 N 10: Eu, Ce, Sr 2 Ge 5 N 8: Eu, Ce, Ba 2 Ge 5 N 8: Eu, _{Pr, Mg 2 Ge 5 N 8} : Eu, Pr, Zn 2 Ge 5 N 8: Eu, Pr, SrGe 7 N 10: Eu, Ce, BaGe 7 N 10: Eu, Pr, MgGe 7 N 10: Eu, Pr _{, ZnGe 7 N 10: Eu,} Ce, Sr 1.8 Ca 0.2 Si 5 N 8: Eu, Pr, Ba 1.8 Ca 0.2 Si 5 N 8: Eu, Ce, Mg 1.8 Ca 0 _.2 Si ₅ N ₈ : Eu, Pr, Zn _1.8 Ca _0.2 Si ₅ N ₈ : Eu, Ce, Sr _0.8 Ca _0.2 Si ₇ N ₁₀ : Eu, La, Ba _0.8 Ca _0.2 Si ₇ N _{10: Eu, La, Mg 0.8} Ca 0.2 Si 7 N 10: Eu, Nd, Zn 0.8 Ca 0.2 Si 7 N 10: Eu, Nd, Sr 0.8 Ca 0.2 Ge 7 _{N 10: Eu, Tb, Ba} 0.8 Ca 0.2 Ge 7 N 10: Eu, Tb, Mg 0.8 Ca 0.2 Ge 7 N 10: Eu, Pr, Zn 0.8 Ca 0.2 Ge ₇ N ₁₀ : Eu, Pr, Sr _0.8 Ca _0.2 Si ₆ GeN ₁₀ : Eu, Pr, Ba _0.8 Ca _0.2 Si ₆ GeN ₁₀ : Eu, Pr, Mg _0.8 Ca _{0.2 Si 6 GeN 10: Eu, Y} , Zn 0.8 Ca 0.2 Si _{GeN 10: Eu, Y, Sr} 2 Si 5 N 8: Pr, Ba 2 Si 5 N 8: Pr, Sr 2 Si 5 N 8: Tb, BaGe 7 N 10: Ce , etc. can be manufactured without limitation.

Mn as an additive promotes diffusion of Eu ²⁺ and improves luminous efficiency such as luminous luminance, energy efficiency, and quantum efficiency. Mn is contained in the raw material, or contains Mn alone or a Mn compound during the manufacturing process, and is fired together with the raw material. However, Mn is not contained in the basic constituent elements after firing, or even if contained, only a small amount remains compared to the initial content. This is probably because Mn was scattered in the firing step.
The phosphor includes Mg, Ga, In, Li, Na, K, Re, Mo, Fe, Sr, Ca, Ba, Zn, B, Al, Cu, in the basic constituent element or together with the basic constituent element. It contains at least one selected from the group consisting of Mn, Cr, O and Ni. These elements have actions such as increasing the particle diameter and increasing the luminance of light emission. Further, B, Al, Mg, Cr and Ni have an effect that afterglow can be suppressed.

  Such a nitride-based phosphor absorbs part of the blue light emitted by the light emitting element and emits light in the yellow to red region. Using a nitride-based phosphor together with a YAG-based phosphor in the light-emitting device having the above-described configuration, the blue light emitted from the light-emitting element and the yellow to red light by the nitride-based phosphor are mixed to produce a warm color system. Provided is a light-emitting device that emits white mixed-color light. It is preferable that the phosphor added in addition to the nitride-based phosphor contains an yttrium / aluminum oxide phosphor activated with cerium. This is because it can be adjusted to a desired chromaticity by containing the yttrium aluminum oxide fluorescent material. The yttrium / aluminum oxide phosphor activated with cerium absorbs part of the blue light emitted by the light emitting element and emits light in the yellow region. Here, the blue light emitted from the light emitting element and the yellow light of the yttrium / aluminum oxide fluorescent material emit light blue-white by mixing colors. Therefore, the yttrium / aluminum oxide phosphor and the phosphor emitting red light are mixed together in a translucent coating member and combined with the blue light emitted by the light emitting element, thereby mixing white color. A light-emitting device that emits light can be provided. Particularly preferred is a light-emitting device that emits white mixed color light whose chromaticity is located on the locus of black body radiation in the chromaticity diagram. However, in order to provide a light emitting device having a desired color temperature, the amount of phosphor of the yttrium / aluminum oxide phosphor and the amount of phosphor of red light emission can be appropriately changed. This light-emitting device that emits white-based mixed color light improves the special color rendering index R9. A conventional white light emitting device consisting only of a combination of a blue light emitting element and an yttrium aluminum oxide phosphor activated with cerium has a special color rendering index R9 of almost 0 at a color temperature of Tcp = 4600K, and a reddish component. Was lacking. For this reason, increasing the special color rendering index R9 has been a problem to be solved. However, in the present invention, the special color rendering index near the color temperature Tcp = 4600K is obtained by using the phosphor emitting red light together with the yttrium aluminum oxide phosphor. R9 can be increased to around 40.

Next, the phosphor according to the present invention: is described a method of manufacturing the _{((Sr X Ca 1-X} ) 2 Si 5 N 8 Eu), but is not limited to this manufacturing method. The phosphor contains Mn and O.

Raw materials Sr and Ca are pulverized. The raw materials Sr and Ca are preferably used alone, but compounds such as imide compounds and amide compounds can also be used. The raw materials Sr and Ca may contain B, Al, Cu, Mg, Mn, MnO, Mn ₂ O ₃ , Al ₂ O ₃ and the like. The raw materials Sr and Ca are pulverized in a glove box in an argon atmosphere. Sr and Ca obtained by pulverization preferably have an average particle diameter of about 0.1 μm to 15 μm, but are not limited to this range. The purity of Sr and Ca is preferably 2N or higher, but is not limited thereto. In order to improve the mixed state, at least one of the metal Ca, the metal Sr, and the metal Eu can be alloyed, nitrided, pulverized, and used as a raw material.

The raw material Si is pulverized. The raw material Si is preferably a simple substance, but a nitride compound, an imide compound, an amide compound, or the like can also be used. For example, Si ₃ N ₄ , Si (NH ₂ ) ₂ , Mg ₂ Si, or the like. The purity of the raw material Si is preferably 3N or more, but Al ₂ O ₃ , Mg, metal borides (Co ₃ B, Ni ₃ B, CrB), manganese oxide, H ₃ BO ₃ , B ₂ O ₃ , Compounds such as Cu ₂ O and CuO may be contained. Si is pulverized in a glove box in an argon atmosphere or a nitrogen atmosphere in the same manner as the raw materials Sr and Ca. The average particle size of the Si compound is preferably about 0.1 μm to 15 μm.

  Next, the raw materials Sr and Ca are nitrided in a nitrogen atmosphere. This reaction formula is shown in the following formula 1 and formula 2, respectively.

3Sr + N ₂ → Sr ₃ N ₂ (Formula 1)
3Ca + N ₂ → Ca ₃ N ₂ (Formula 2)
Sr and Ca are nitrided in a nitrogen atmosphere at 600 to 900 ° C. for about 5 hours. Sr and Ca may be mixed and nitrided, or may be individually nitrided. Thereby, a nitride of Sr and Ca can be obtained. Sr and Ca nitrides are preferably of high purity, but commercially available ones can also be used.

  The raw material Si is nitrided in a nitrogen atmosphere. This reaction formula is shown in the following formula 3.

3Si + 2N ₂ → Si ₃ N ₄ (Formula 3)
Silicon Si is also nitrided in a nitrogen atmosphere at 800 to 1200 ° C. for about 5 hours. Thereby, silicon nitride is obtained. The silicon nitride used in the present invention is preferably highly pure, but commercially available ones can also be used.

Sr, Ca or Sr—Ca nitride is pulverized. Sr, Ca, and Sr—Ca nitrides are pulverized in a glove box in an argon atmosphere or a nitrogen atmosphere.
Similarly, Si nitride is pulverized. Similarly, the Eu compound Eu ₂ O ₃ is pulverized. Europium oxide is used as the Eu compound, but metal europium, europium nitride, and the like can also be used. In addition, as the raw material Z, an imide compound or an amide compound can be used. Europium oxide is preferably highly purified, but commercially available products can also be used. The average particle size of the alkaline earth metal nitride, silicon nitride and europium oxide after pulverization is preferably about 0.1 μm to 15 μm.

The raw material may contain at least one selected from the group consisting of Mg, Sr, Ca, Ba, Zn, B, Al, Cu, Mn, Cr, O, and Ni. Further, the above elements such as Mg, Zn, and B can be mixed by adjusting the blending amount in the following mixing step. These compounds can be added alone to the raw material, but are usually added in the form of compounds. Such compounds include H ₃ BO ₃ , Cu ₂ O ₃ , MgCl ₂ , MgO · CaO, Al ₂ O ₃ , metal borides (CrB, Mg ₃ B ₂ , AlB ₂ , MnB), B ₂ O ₃ , Cu ₂ O, CuO, and the like.

After the pulverization, Sr, Ca, Sr—Ca nitride, Si nitride, and Eu compound Eu ₂ O ₃ are mixed, and Mn is added. Since these mixtures are easily oxidized, they are mixed in a glove box in an Ar atmosphere or a nitrogen atmosphere.

Finally, a mixture of Sr, Ca, Sr—Ca nitride, Si nitride, and Eu compound Eu ₂ O ₃ is fired in an ammonia atmosphere. A phosphor represented by (Sr _X Ca _1-X ) ₂ Si ₅ N ₈ : Eu to which Mn is added can be obtained by firing. However, the composition of the target phosphor can be changed by changing the blending ratio of each raw material.

For firing, a tubular furnace, a small furnace, a high-frequency furnace, a metal furnace, or the like can be used. Firing can be performed in the range of 1200 to 1700 ° C., but a firing temperature of 1400 to 1700 ° C. is preferable. It is preferable to use a one-step baking in which the temperature is gradually raised and baking is performed at 1200 to 1500 ° C. for several hours, but the first step baking is performed at 800 to 1000 ° C. Two-stage baking (multi-stage baking) in which the second baking is performed at 1500 ° C. can also be used. The phosphor material is preferably fired using a boron nitride (BN) crucible or boat. Besides the crucible made of boron nitride, a crucible made of alumina (Al ₂ O ₃ ) can also be used.

  By using the above manufacturing method, it is possible to obtain a target phosphor.

In the embodiment of the present invention, a nitride-based phosphor is used as the phosphor that emits reddish light. In the present invention, the above-described YAG-based phosphor can emit red light. It is also possible to provide a light emitting device including a simple phosphor. Such a phosphor capable of emitting red light is a phosphor that emits light when excited by light having a wavelength of 400 to 600 nm. For example, Y ₂ O ₂ S: Eu, La ₂ O ₂ S: Eu. CaS: Eu, SrS: Eu, ZnS: Mn, ZnCdS: Ag, Al, ZnCdS: Cu, Al and the like. As described above, the color rendering property of the light emitting device can be improved by using the phosphor capable of emitting red light together with the YAG phosphor.

  The phosphors capable of emitting red light typified by the aluminum garnet-based phosphor and nitride-based phosphor formed as described above are included in two wavelength conversion members in the vicinity of the light-emitting element. One or more types may be present, or one type or two or more types may be present in the two-layer wavelength conversion member. With such a configuration, it is possible to obtain mixed color light by mixing light from different types of phosphors. In this case, it is preferable that the average particle diameters and shapes of the phosphors are similar in order to better mix the light emitted from the phosphors and reduce color unevenness. Also, considering that the nitride-based phosphor absorbs part of the light that has been wavelength-converted by the YAG-based phosphor, the nitride-based phosphor is disposed closer to the light emitting element than the YAG-based phosphor. It is preferable to form the wavelength conversion member as described above. With this configuration, a part of the light wavelength-converted by the YAG phosphor is not absorbed by the nitride phosphor, and the YAG phosphor and the nitride phosphor are mixed. The color rendering properties of mixed color light can be improved as compared with the case where it is contained.

(Alkaline earth metal silicate)
The light-emitting device in this embodiment mode uses alkaline earth activated by europium as a phosphor that absorbs part of light emitted from a light-emitting element and emits light having a wavelength different from the wavelength of the absorbed light. It can also have a metal silicate. The alkaline earth metal silicate can be a light-emitting device that emits warm color mixed light using blue light as excitation light. The alkaline earth metal silicate is preferably an alkaline earth metal orthosilicate represented by the following general formula.
(2-x-y) SrO · x (Ba, Ca) O · (1-a-b-c-d) SiO 2 · aP 2 O 5 bAl 2 O 3 cB 2 O 3 dGeO 2: yEu 2+ ( Equation Medium, 0 <x <1.6, 0.005 <y <0.5, 0 <a, b, c, d <0.5.)
(2-x-y) BaO · x (Sr, Ca) O · (1-a-b-c-d) SiO 2 · aP 2 O 5 bAl 2 O 3 cB 2 O 3 dGeO 2: yEu 2+ ( Equation (Inside, 0.01 <x <1.6, 0.005 <y <0.5, 0 <a, b, c, d <0.5.)
Here, preferably, at least one of the values of a, b, c and d is greater than 0.01.

The light-emitting device in the present embodiment is a phosphor composed of an alkaline earth metal salt. In addition to the alkaline earth metal silicate described above, alkaline earth metal aluminate or Y activated by europium and / or manganese is used. (V, P, Si) O ₄ : Eu, or an alkaline earth metal-magnesium-disilicate represented by the following formula:

Me (3-xy) MgSi ₂ O ₃ : xEu, yMn (wherein 0.005 <x <0.5, 0.005 <y <0.5, Me represents Ba and / or Sr and / or Or Ca.)
Next, the manufacturing process of the phosphor made of alkaline earth metal silicate in the present embodiment will be described.

  For the production of alkaline earth metal silicates, the stoichiometric amounts of the starting materials alkaline earth metal carbonate, silicon dioxide and europium oxide are intimately mixed according to the selected composition, and the phosphor is produced. In a conventional solid reaction, the desired phosphor is converted at a temperature of 1100 ° C. and 1400 ° C. under a reducing atmosphere. At this time, it is preferable to add less than 0.2 mol of ammonium chloride or other halide. If necessary, part of silicon can be replaced with germanium, boron, aluminum, and phosphorus, and part of europium can be replaced with manganese.

One of the phosphors as described above, ie, alkaline earth metal aluminates activated with europium and / or manganese, Y (V, P, Si) O ₄ : Eu, Y ₂ O ₂ S: Eu ³⁺ By combining one or these phosphors, as shown in the following table as an example, it is possible to obtain an emission color having a desired color temperature and high color reproducibility.

（その他の蛍光体）
本実施の形態において、蛍光体として紫外光により励起されて発光する蛍光体も用いることができ、具体例として、以下の蛍光体が挙げられる。
（１）Ｅｕ、ＭｎまたはＥｕとＭｎで付活されたアルカリ土類ハロゲンアパタイト蛍光体；例えば、Ｍ_５（ＰＯ_４）_３（Ｃｌ、Ｂｒ）：Ｅｕ（但し、ＭはＳｒ、Ｃａ、Ｂａ、Ｍｇから選択される少なくとも一種）、Ｃａ_１０（ＰＯ_４）_６ＣｌＢｒ：Ｍｎ、Ｅｕなどの蛍光体。
（２）Ｅｕ、ＭｎまたはＥｕとＭｎで付活されたアルカリ土類アルミン酸塩蛍光体；例えば、ＢａＭｇ_２Ａｌ_１６Ｏ_２７：Ｅｕ、ＢａＭｇ_２Ａｌ_１６Ｏ_２７：Ｅｕ，Ｍｎ、Ｓｒ_４Ａｌ_１４Ｏ_２５：Ｅｕ、ＳｒＡｌ_２Ｏ_４：Ｅｕ、ＣａＡｌ_２Ｏ_４：Ｅｕ、ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ、ＢａＭｇＡｌ_１０Ｏ_１７：Ｅｕ，Ｍｎなどの蛍光体。
（３）Ｅｕで付活された希土類酸硫化物蛍光体；例えば、Ｌａ_２Ｏ_２Ｓ：Ｅｕ、Ｙ_２Ｏ_２Ｓ：Ｅｕ、Ｇｄ_２Ｏ_２Ｓ：Ｅｕなどの蛍光体。
（４）（Ｚｎ、Ｃｄ）Ｓ：Ｃｕ、Ｚｎ_２ＧｅＯ_４：Ｍｎ、３．５ＭｇＯ・０．５ＭｇＦ_２・ＧｅＯ_２：Ｍｎ、Ｍｇ_６Ａｓ_２Ｏ_１１：Ｍｎ、（Ｍｇ、Ｃａ、Ｓｒ、Ｂａ）Ｇａ_２Ｓ_４：Ｅｕ、Ｃａ_１０（ＰＯ_４）_６ＦＣｌ：Ｓｂ，Ｍｎ、や（５）Ｅｕで付活された有機錯体蛍光体。

(Other phosphors)
In the present embodiment, a phosphor that emits light when excited by ultraviolet light can also be used as the phosphor, and specific examples include the following phosphors.
(1) Eu, Mn or alkaline earth halogen apatite phosphor activated with Eu and Mn; for example, M ₅ (PO ₄ ) ₃ (Cl, Br): Eu (where M is Sr, Ca, Ba, Phosphors such as at least one selected from Mg), Ca ₁₀ (PO ₄ ) ₆ ClBr: Mn, Eu.
(2) Eu, Mn or alkaline earth aluminate phosphor activated by Eu and Mn; for example, BaMg ₂ Al ₁₆ O ₂₇ : Eu, BaMg ₂ Al ₁₆ O ₂₇ : Eu, Mn, Sr ₄ Al ₁₄ Phosphors such as O ₂₅ : Eu, SrAl ₂ O ₄ : Eu, CaAl ₂ O ₄ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, Mn and the like.
(3) A rare earth oxysulfide phosphor activated with Eu; for example, a phosphor such as La ₂ O ₂ S: Eu, Y ₂ O ₂ S: Eu, or Gd ₂ O ₂ S: Eu.
(4) (Zn, Cd) S: Cu, Zn ₂ GeO ₄ : Mn, 3.5 MgO · 0.5 MgF ₂ · GeO ₂ : Mn, Mg ₆ As ₂ O ₁₁ : Mn, (Mg, Ca, Sr, Ba _{) Ga 2 S 4: Eu,} Ca 10 (PO 4) 6 FCl: Sb, Mn, and (5) activated organic complex phosphors with Eu.

  In addition, these phosphors may be used alone in a single-layer wavelength conversion member, or may be used as a mixture. Furthermore, they may be used alone or in combination in a wavelength conversion member in which two or more layers are laminated.

[LED chip 103]
An LED chip will be described as a light emitting element in this embodiment. Examples of semiconductor light-emitting elements that constitute LED chips include those using various semiconductors such as ZnSe and GaN. When a fluorescent material is used, a short wavelength that can excite the fluorescent material efficiently is emitted. possible nitride semiconductor _{(in X Al Y Ga 1-} X-Y N, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) is preferably exemplified. Examples of the semiconductor structure include a homostructure having a MIS junction, a PIN junction, and a pn junction, a heterostructure, or a double heterostructure. Various emission wavelengths can be selected depending on the material of the semiconductor layer and the degree of mixed crystal. In addition, a single quantum well structure or a multiple quantum well structure in which the semiconductor active layer is formed in a thin film in which a quantum effect is generated can be used.

  When a nitride semiconductor is used, a material such as sapphire, spinel, SiC, Si, ZnO is preferably used for the semiconductor substrate. In order to form a nitride semiconductor with good crystallinity with high productivity, it is preferable to use a sapphire substrate. A nitride semiconductor can be formed on the sapphire substrate by MOCVD or the like. A buffer layer of GaN, AlN, GaAlN or the like is formed on the sapphire substrate, and a nitride semiconductor having a pn junction is formed thereon.

  As an example of a light emitting device having a pn junction using a nitride semiconductor, a first contact layer formed of n-type gallium nitride, a first clad layer formed of n-type aluminum nitride / gallium on a buffer layer, Examples include a double hetero structure in which an active layer formed of indium / gallium nitride, a second cladding layer formed of p-type aluminum nitride / gallium, and a second contact layer formed of p-type gallium nitride are sequentially stacked. .

  Nitride semiconductors exhibit n-type conductivity without being doped with impurities. When forming a desired n-type nitride semiconductor, for example, to improve luminous efficiency, it is preferable to appropriately introduce Si, Ge, Se, Te, C, etc. as an n-type dopant. On the other hand, when forming a p-type nitride semiconductor, the p-type dopants such as Zn, Mg, Be, Ca, Sr, and Ba are doped. Since nitride semiconductors are not easily converted to p-type by simply doping with a p-type dopant, it is preferable to reduce resistance by heating in a furnace or plasma irradiation after introducing the p-type dopant.

  The p-type semiconductor layer is provided with a diffusion electrode for spreading the current input to the light emitting element over the entire surface of the p-type semiconductor layer. Furthermore, a p-side pedestal electrode and an n-side pedestal electrode connected to a conductive member such as a bump or a conductive wire are provided on the diffusion electrode and the n-type semiconductor layer, respectively. The diffusion electrode, the p-side pedestal electrode, and the n-side pedestal electrode are formed by vapor deposition or sputtering after exposing the n-type semiconductor layer by a method such as etching. Here, it is preferable to form both positive and negative electrodes parallel to each other, because it can be stably mounted on the support substrate, and since the current flowing between the electrodes becomes uniform, the light emission from the light emitting surface of the light emitting element becomes uniform. .

  In the light-emitting element in this embodiment, it is preferable that p-side pedestal electrodes and n-side pedestal electrodes are alternately arranged in a stripe shape. Moreover, it is preferable that the number of p-side pedestal electrodes provided linearly on the p-type semiconductor layer is larger than the number of n-side pedestal electrodes. Further, the width of the p-side pedestal electrode when viewed from the direction of the emission observation surface is wider than the width of the n-side pedestal electrode. Further, the area of the p-side pedestal electrode when viewed from the light emission observation plane direction is wider than the area of the n-side pedestal electrode. In general, in the light emitting element, how to dissipate heat generated in the semiconductor stacked structure from the p-type semiconductor layer to the lower layer becomes a problem in improving the heat dissipation of the element. Accordingly, the p-side pedestal electrode and the n-side pedestal electrode are configured as described above, and the number of conductive members provided on the p-side pedestal electrode is larger than that of the n-side pedestal electrode, thereby improving the heat dissipation of the light emitting element. . Furthermore, the light extraction efficiency of the light-emitting element can be improved by reducing the area where the n-side pedestal electrode that does not contribute to light emission of the light-emitting element is formed and relatively increasing the area of the p-side pedestal electrode. In this embodiment, when the p-side pedestal electrode and the n-side pedestal electrode are alternately arranged in a stripe shape, the bump bonding position of the n-type pedestal electrode is set to both corners of the strip-shaped n-type pedestal electrode.

  In this embodiment, the material of the p-side pedestal electrode and / or the electrode formed on the entire surface of the p-type semiconductor layer is preferably a material that reflects light emitted from the light-emitting element toward the light-transmitting substrate of the light-emitting element. For example, Ag, Al, Rh, Rh / Ir can be mentioned. In addition, a metal thin film such as ITO (complex oxide of indium (In) and tin (Sn)) or Ni / Au can be formed as a translucent electrode on the entire surface of the p-type semiconductor layer.

  When a transparent substrate such as sapphire is used as the substrate, after forming both positive and negative electrodes, by cutting into a chip shape from the semiconductor wafer, a nitride semiconductor chip provided with both positive and negative electrodes on the same surface side is obtained, A light emitting element can be formed.

  When light is emitted in the light emitting device of the present invention, the main light emission wavelength of the LED chip 103 is preferably 350 nm or more and 530 nm or less in consideration of a complementary color with a phosphor or the like.

[Support substrate 101]
The support substrate (submount) in this embodiment is provided with a conductive pattern on at least a surface facing the light emitting element. In the case where the support substrate is placed on the lead electrode to conduct, the conductive pattern is applied by the conductive member from the surface facing the light emitting element to the surface facing the lead electrode. The conductive pattern in the present invention is formed by supplying electric power from the external lead electrode to the light emitting element, and a pair of positive and negative wiring patterns are insulated and separated from the support substrate. The metal used as the material of the conductive pattern is selected in consideration of good adhesion between metals, so-called wettability. For example, when an electrode of an LED chip containing Au is bonded by an ultrasonic die bond via an Au bump, the conductive pattern is made of Au or an alloy containing Au.

  The material of the support substrate is preferably aluminum nitride with respect to a light emitting element having substantially the same thermal expansion coefficient as that of the nitride semiconductor light emitting element. By using such a material, the influence of thermal stress generated between the support substrate and the light-emitting element can be reduced. Alternatively, the material of the support substrate is preferably silicon which can be provided with a Zener diode function and is inexpensive. For example, a p-type semiconductor region can be formed by selectively implanting impurity ions into an n-type silicon substrate.

  When the submount is a Zener diode, p-type and n-type semiconductors are formed on the surface side of the submount, and the electrodes provided as part of the conductive pattern on the p-type and n-type semiconductors are respectively light emitting elements. The negative electrode and the positive electrode are connected in reverse parallel via bumps. Alternatively, either the p-type or the n-type semiconductor is formed on the surface side of the submount, and either the n-type semiconductor or the p-type semiconductor is formed on the back surface side of the submount so that the polarity is different from the surface side. Either one is formed. Here, on the surface side of the submount, the electrodes provided as part of the conductive pattern on the p-type or n-type semiconductor are electrically and mechanically connected to the negative electrode and the positive electrode of the light-emitting element through bumps, respectively. Is done.

  The material of the conductive pattern of the submount is preferably a silver white metal having a high reflectance, such as aluminum, silver, gold, or an alloy thereof. Furthermore, it is preferable to provide a hole or a concavo-convex shape with respect to the supporting substrate in a place where the mounting of the light emitting element is not adversely affected. By providing such a shape, heat from the semiconductor element can be efficiently radiated from the support. It is preferable to provide at least one or more through holes in the thickness direction of the support substrate so that the conductive member extends on the inner wall surface of the through holes because heat dissipation is further improved. In addition, although the support substrate in this Embodiment has connected the lead electrode and the conductive pattern via the conductive wire, it is good also as a structure which connects a conductive pattern and a lead electrode directly.

  The conductive pattern provided on the support substrate is connected to the electrodes of the semiconductor element by ultrasonic bonding using a bonding member such as Au, eutectic solder (Au—Sn, Pb—Sn), lead-free solder, or the like. Further, the connection between the conductive pattern provided on the support substrate and the lead electrode exposed in the recess of the package is performed by a bonding member such as Au paste or Ag paste.

[Conductive member 102]
The light emitting device in this embodiment can be a light emitting device in which at least one of a pair of positive and negative electrodes of a light emitting element is bonded to a conductive pattern of a support substrate via a conductive member. The conductive member used for joining the positive and negative electrodes of the LED chip and the conductive pattern of the support substrate is a metal material called a bump having at least one kind of the same material as the positive and negative electrodes and the conductive pattern. For example, it is a bump made of an Au bump generally used in ultrasonic bonding, Sn-Pb, an alloy containing Au, or the like. Here, when a bump that partially absorbs light from the light emitting element, such as Au, is selected, it is preferable to increase the concentration of the diffusing agent in the resin layer near the bump. Note that this configuration is not particularly essential when the electrode of the light emitting element includes a silver foil metal having a high reflectance. Further, the bump is preferably a metal element contained in the electrode of the LED chip in the present invention and contains at least one metal element contained in the conductive pattern of the support substrate. By doing in this way, since the joining strength of the electrode of a light emitting element, a conductive member, and a conductive pattern improves, it is preferable.

[Sealing member 107]
A sealing member can be further provided so as to cover the wavelength conversion member in this embodiment. For example, as shown in FIG. 2, the material of the sealing member 107 can be easily positioned by using the upper end portion of the first wavelength conversion member as a barrier. Furthermore, the sealing member 107 can be covered with another sealing member having a different refractive index. The material of the sealing member is not particularly limited as long as it is translucent, and translucent with excellent weather resistance such as silicone resin, epoxy resin, urea resin, fluororesin, and hybrid resin including at least one of those resins. Can be used. Further, the sealing member is not limited to an organic material, and a light-transmitting inorganic member obtained by a sol-gel method using one or more metal alkoxides as a starting material, or an inorganic material having excellent light resistance such as glass can also be used. In the present embodiment, any member can be added to the sealing member depending on the intended use, such as a viscosity extender, a light diffusing agent, a pigment, and a fluorescent substance. Examples of the light diffusing agent include barium titanate, titanium oxide, aluminum oxide, silicon oxide, silicon dioxide, heavy calcium carbonate, light calcium carbonate, and a mixture containing at least one of them. Furthermore, a lens effect can be provided by making the light emitting surface side of the sealing member have a desired shape, and light emitted from the light emitting element chip can be focused. Specifically, a convex lens shape, a concave lens shape, an elliptical shape as viewed from the light emission observation surface, or a shape obtained by combining a plurality of them can be used.

  Examples according to the present invention will be described in detail below. Needless to say, the present invention is not limited to the following examples.

  As shown in FIG. 1, the light emitting device according to this example includes a first wavelength conversion member 104 formed so as to cover the side end surface side of the LED chip 103 flip-chip mounted on the submount 101. And the second wavelength conversion member 105 formed by screen printing so as to cover the translucent substrate 210 of the LED chip 103. The first and second wavelength conversion members contain a phosphor with silicone resin as a binder, and the upper portion of the first wavelength conversion member 104 serves as a barrier for the second wavelength conversion member 105, and the second The wavelength conversion member 105 is configured so as not to spill from the light-transmitting substrate side of the LED chip 103. Further, the first wavelength conversion member 104 is separated from the bump 102 that joins the p and n base electrodes 208 and 209 of the LED chip 103 and the conductive pattern of the submount 101 on the side of the LED chip 103. . That is, a gap is provided between the wavelength conversion member 104 and the bump 102.

The LED chip 103 in this embodiment uses a nitride semiconductor element having a 475 nm In _0.2 Ga _0.8 N semiconductor having a monochromatic emission peak of visible light as an active layer. More specifically, the LED chip 103, which is a light emitting element, flows TMG (trimethyl gallium) gas, TMI (trimethyl indium) gas, nitrogen gas and dopant gas together with a carrier gas on a cleaned sapphire substrate, It can be formed by depositing a nitride semiconductor. A layer to be an n-type nitride semiconductor or a p-type nitride semiconductor is formed by switching between SiH ₄ and Cp ₂ Mg as the dopant gas.

As an element structure of the LED chip 103 of this embodiment, a GaN layer that is an undoped nitride semiconductor, an n-type GaN layer that becomes an n-type contact layer on which an Si-doped n-type electrode is formed, and an undoped layer. A GaN layer that is a nitride semiconductor is laminated, and further, a GaN layer that becomes a barrier layer and an InGaN layer that becomes a well layer are laminated as 5 sets, and finally a GaN layer that becomes a barrier layer is laminated as an active layer. The active layer has a multiple quantum well structure. Furthermore, an AlGaN layer as a p-type cladding layer doped with Mg and a p-type GaN layer as a p-type contact layer doped with Mg are sequentially laminated on the active layer. (Note that a GaN layer is formed on the sapphire substrate at a low temperature to serve as a buffer layer. The p-type semiconductor is annealed at 400 ° C. or higher after film formation.)
Etching exposes the surfaces of the p-type contact layer and the n-type contact layer on the same side of the nitride semiconductor on the sapphire substrate. Next, sputtering using Rh and Ir as materials is sequentially performed on the p-type contact layer, and the diffusion electrode 211 is provided on almost the entire surface of the p-type contact layer exposed in a stripe shape. By setting it as such an electrode, the electric current which flows through the diffused electrode 211 can be spread over a wide range of a p-type contact layer, and the luminous efficiency of an LED chip can be improved. Further, since the light emitted from the LED chip 103 is reflected by the diffusion electrode 211 on the entire surface and emitted from the direction of the sapphire substrate, the light extraction efficiency from the LED chip 103 mounted in a flip chip can be improved.

  Further, sputtering using W, Pt, and Au as materials is sequentially performed, and the p-side pedestal electrode 208 and the n-side pedestal electrode 209 are simultaneously formed by laminating the diffusion electrode 211 and a part of the n-type contact layer. Here, by forming the p-side pedestal electrode 208 and the n-side pedestal electrode 209 simultaneously, the number of steps for forming the electrode can be reduced.

  Next, the submount 101 which is a support substrate in the present embodiment will be described. As shown in FIG. 1, a submount 101 used in an embodiment of the present invention has an aluminum nitride plate provided with a conductive pattern made of Au, and p-side pedestal electrodes 208 and n via bumps 103. A pair of positive and negative electrodes facing the side pedestal electrode 209 are insulated and separated.

  Hereinafter, a method for forming a light emitting device in this embodiment will be described. 9 and 10 are schematic perspective views showing a method for forming the first wavelength conversion member according to the present embodiment, and FIG. 12 shows a method for forming the second wavelength conversion member according to the present embodiment. It is a typical sectional view shown.

  First, after bump 103 is formed and leveled by a bump bonder on an aluminum nitride wafer having a conductive pattern formed by plating using Au as a material, a pair of positive and negative electrodes 208 and 209 of LED chip 103 are provided on conductive pattern 207. The bumps 102 face each other. Then, the LED chip 103 and the conductive pattern 207 of the submount 101 are joined by applying a load, heat, and ultrasonic waves.

The fluorescent material is prepared by co-precipitation with oxalic acid of a solution obtained by dissolving a rare earth element of Y, Gd, and Ce in an acid at a stoichiometric ratio with oxalic acid, and calcining the mixture, and then mixing aluminum oxide. To obtain a mixed raw material. Further, barium fluoride is mixed as a flux, then packed in a crucible, and fired in air at a temperature of 1400 ° C. for 3 hours to obtain a fired product. The fired product is ball _milled in water, washed, separated, dried, and finally passed through a sieve to have a center particle size of 8 μm (Y _0.995 Gd _0.005 ) _2.750 Al ₅ O ₁₂ : Ce _0.250 phosphor Form. The above-mentioned fluorescent material is contained in a silicone resin composition in an amount of 20 to 75 wt%, and the mixture is stirred for 5 minutes with a rotation and revolution mixer to obtain a curable composition 201 that is a mixture of a phosphor and a silicone resin that is a binder. .

  As shown in FIG. 9, the obtained curable composition 201 is supplied to the periphery of the light emitting element by a dispenser 202 so as to be in contact with the side end portion of the LED chip 103. Specifically, the periphery of the LED chip 103 is surrounded by the curable composition 201, and the periphery of the LED chip 103 is circled, and then the discharge port of the dispenser 202 is moved inward of the LED chip 103 to end the supply. At this time, the viscosity of the mixture is adjusted so that the paste-like mixture is continuously supplied from the discharge port of the dispenser. The width of the curable composition 201 to be supplied is about 100 μm, and the height of the curable composition 201 from the submount is adjusted to be about 100 μm higher than the height of the LED chip at the upper end. Further, the interval between the LED chip side wall surface of the wavelength conversion member 104 and the closest bump 102 is adjusted to be 40 to 50 μm.

  Next, the sapphire substrate surface which is the main surface side of the LED chip 103 is coated, and the curable composition 203 is screen-printed so as to be within the edge of the curable composition 201 supplied in the previous step. Print. As shown in FIG. 12, a screen plate 204 is arranged, and squeegee 205 is used for squeezing to print curable composition 203. Further, the wavelength conversion members 104 and 105 having a layer thickness of about 100 μm are uniformly formed around the LED chip 103 by being left to stand for a predetermined time and thermally cured when the surface of the curable composition 203 is flattened. Form.

  Finally, the aluminum nitride wafer is cut along the parting line so that the desired number of LED chips are mounted on the same submount.

  FIG. 7 is a schematic top view of the light emitting device in this example, and FIG. 8 is a cross-sectional view taken along line AA of the light emitting device shown in FIG. In this embodiment, the LED chip mounted on the submount is fixed to the bottom surface 214 of the recess of the package 213 with silver paste, as shown in FIGS. Further, the conductive pattern of the submount 101 and the lead electrode 215 exposed in the vicinity of the bottom surface 214 of the recess of the package 213 are connected by the conductive wire 212 to obtain a light emitting device. Here, the package 213 in this embodiment is integrally molded so that a part of the metal base 217 and the lead electrode 215 is covered with the molding resin by injection molding using the molding resin as a material. Further, since the metal base 217 has a concave bottom surface 214 for mounting the LED chip 103 and is made of a metal having good thermal conductivity, the heat dissipation of the light emitting device can be improved. Further, the sealing member 107 in this embodiment is configured such that a first portion made of a gel-like silicone resin that fills the recess and covers the periphery of the conductive wire 212 is bonded to the first portion and the lens 216. It is set as the multilayer structure which has the 2nd site | part which consists of a rubber-like silicone resin to do. In this manner, by covering the conductive wire with a flexible gel-like silicone resin, disconnection of the conductive wire can be prevented and a highly reliable light-emitting device can be obtained.

  FIG. 13 is a diagram illustrating the state of the color temperature of the mixed color light depending on the observation direction (angle) of the light emitting device according to the present example. In a conventional light emitting device as a comparative example, a resin containing a phosphor is formed around a light emitting element by potting. As described above, the light emitting device in this embodiment can reduce the change in the color temperature of the mixed color light depending on the light emission observation direction as compared with the conventional case.

  A light emitting device is formed in the same manner as in Example 1 except that the first wavelength conversion member is molded with a metal mask, the metal mask is removed, and the first and second wavelength conversion members are formed.

  The light emitting device according to the present embodiment can obtain optical characteristics substantially equivalent to those of the light emitting device according to the first embodiment.

  FIG. 2 is a schematic cross-sectional view of the light emitting device according to this example. In the light emitting device according to this example, the upper end portion of the first wavelength conversion member 104 protrudes from a plane including the main surface of the second wavelength conversion member 105 on the light emission observation surface side. That is, the height of the first wavelength conversion member 104 from the conductive pattern 207 is higher than the height of the outermost surface on the light emission observation surface side of the second wavelength conversion member 105. Accordingly, the sealing member 107 can be formed by using the upper end portion of the first wavelength conversion member as a barrier, positioning so as not to spill silicon resin, covering the second wavelength conversion member, and curing. The formed sealing member 107 has a curved surface on the light emission observation surface side and has a lens shape. Except for the formation as described above, the light emitting device is formed in the same manner as in the other examples.

  With the light emitting device of this embodiment, the light distribution can be controlled and the light extraction efficiency of the light emitting device can be improved.

  FIG. 3 is a schematic cross-sectional view of the light emitting device according to this example. The first wavelength conversion member and the second wavelength conversion member in the present embodiment are formed of two layers having different types of phosphors contained therein. That is, the wavelength conversion member in the present embodiment is arranged so as to cover the first and second wavelength conversion members 104b and 105b containing the nitride-based phosphors arranged closer to the LED chip 103, and them. The first and second wavelength conversion members 104a and 105a containing the YAG-based phosphor. In such a wavelength conversion member, first, a curable composition containing a nitride-based phosphor is supplied around the LED chip 103, and then a curable composition containing a YAG-based phosphor around the curable composition. It can be formed by supplying and curing the composition.

  By adopting the configuration of the wavelength conversion member of this example, the light emission of the YAG phosphor is not absorbed by the nitride phosphor, so that a light emitting device with improved color rendering can be obtained.

  FIG. 4 is a schematic cross-sectional view of the light emitting device according to this example. The light emitting device according to this example includes an underfill material 206 between the positive and negative electrodes of the LED chip 103 and the submount 101, and between the first wavelength conversion member 104, the bump 102, and the submount 101. Therefore, the first wavelength conversion member 104 is separated from both the submount 101 and the bump 102. In the first wavelength conversion member 104 in the present embodiment, the underfill material 206 is supplied to a predetermined position and cured, and then the curable composition is supplied around the LED chip 103 and on the underfill material 206. Formed. At this time, an interface is formed between the first wavelength conversion member 104 and the underfill material 206. However, in consideration of the adhesion between the first wavelength conversion member 104 and the underfill material 206, it is preferable not to generate an interface between the two by curing them simultaneously.

  With the configuration of the wavelength conversion member of this embodiment, heat dissipation from the LED chip 103 to the submount 101 via the underfill material 206 is promoted, and the phosphor is a heating element such as a bump or submount. Are arranged at intervals from each other, a decrease in luminance of the phosphor is suppressed, and a light emitting device with high luminous efficiency can be obtained.

  FIG. 5 is a schematic cross-sectional view of the light emitting device according to this example. The light emitting device in this example is the same as that in Example 5 in that it has an underfill material 206, but the formation method and the location of the underfill material are different. That is, the underfill material 206 in this embodiment is formed by first curing the first wavelength conversion member 104 with a predetermined interval from the side surface of the LED chip 103, and then the side surface of the LED chip 103 and the first wavelength conversion member. It is formed by injecting and curing a silicone resin having permeability from a gap formed between it and 104. In general, the distance between the flip-chip mounted LED chip 103 and the submount 101 is as narrow as several tens of μm, and the bumps 102 are also present. Therefore, the material of the underfill material 206 is preferably permeable. Therefore, by using the formation method as described above, it is possible to prevent sagging of the penetrating silicone resin and easily form the underfill material at a predetermined position. Furthermore, after forming the underfill material 206, the second wavelength conversion member 105 forms a phosphor so as to cover the first wavelength conversion member 104, the side surface and the main surface of the light emitting element, and the underfill material 206. It forms by supplying and hardening the curable composition containing.

  In addition, the second wavelength conversion member 105 in this embodiment is interposed between the side surface of the LED chip 103 and the first wavelength conversion member 104 by using the above-described formation method, and the light emission observation surface of the LED chip 103. It is firmly fixed and held in the side main surface direction. Therefore, the second wavelength conversion member is prevented from coming off and a highly reliable light emitting device can be obtained.

  In the present embodiment, the first wavelength conversion member 104 is separated from the bumps 102 that are heating elements, and the second wavelength conversion member 105 is separated from both the bumps 102 that are heating elements and the submount 101. Therefore, a decrease in luminance of the phosphor due to heat generation of the light emitting device is suppressed, and a light emitting device with high luminous efficiency can be obtained.

  FIG. 6 is a schematic cross-sectional view of the light emitting device according to this example. FIG. 7 is a schematic top view of the light emitting device according to this example, and FIG. 8 is a cross-sectional view taken along the dotted line AA shown in FIG. The light emitting device according to this example has the same configuration as that of the other examples except that the first and second wavelength conversion members 104 and 105 are covered with the sealing member 107. Further, as shown in FIG. 8, another sealing member 107 having a refractive index different from that of the sealing member 107 covering the first and second wavelength conversion members 104 and 105 is filled, and the lens 216 is placed. A light emitting device.

  With the configuration of this example, a light-emitting device with little change in color temperature depending on the emission observation direction can be obtained.

  The method of forming the light emitting device in this example is the same as the other examples described above, except that the application method of the curable composition is different. Hereinafter, the method for forming the wavelength conversion member will be described in detail with reference to cross-sectional views showing the steps for forming the wavelength conversion member in the present embodiment.

  Step 1. As shown in FIG. 14, a metal mask 219 is arranged on the LED chip 103 flip-chip mounted on the support substrate 101. The metal mask 219 is formed of a metal material, and has a through-hole having a size that allows the outline of the LED chip 103 to be accommodated. The inner wall surface of the through hole faces the side surface of the LED chip 103 and molds a part of the outer surface of the wavelength conversion member. Therefore, it is preferable that the inner wall surface of the through hole is smooth and has high releasability with respect to the applied curable composition. Further, a difference is provided in the height between the upper surface of the LED chip 103 (the main surface on the side not facing the support substrate 101) and the upper surface of the metal mask 219, so that the side surface of the LED chip 103 and the inner wall surface of the through hole are provided. A predetermined interval for disposing the curable composition is provided between them.

Step 2. As shown in FIG. 15, by moving the squeegee 205 while applying a predetermined pressure, (Y ₀ ...) As a curable composition in a gap formed between the side surface of the LED chip 103 and the inner wall surface of the through hole _. A silicone resin containing 10 wt% of a phosphor represented by ₈ Gd _0.2 ) ₃ Al ₅ O ₁₂ : Ce is injected. At this time, as illustrated in FIG. 16, the phosphor-containing silicone resin is moved around the LED chip 103 by moving the phosphor-containing silicone resin while pressing the squeegee so that the upper surface of the LED chip 103 is worn.

  In this example, “FLOW value” is defined as an index indicating the fluidity of the resin material contained in the curable composition. The “FLOW value” in the present embodiment is a numerical value of the size of a region where a resin material placed on a horizontal plane flows and spreads at a predetermined temperature. That is, the FLOW value of the silicone resin in this example is the maximum diameter (mm) of the region where the silicone resin spreads in the horizontal direction when 1 g of the silicone resin placed on the horizontal surface is heated at 150 ° C. for 1 hour. . The FLOW value in this process 2 is 8.5 mm to 11 mm. This value is a value prepared so that no sagging occurs in the curable composition after the metal mask is removed.

  Step 3. As shown in FIG. 17, a phosphor-containing silicone resin is applied to the upper surface side of the LED chip 103. In addition, the phosphor-containing silicone resin in this step 3 has a FLOW value larger than that of the phosphor-containing silicone resin in the above step 2, and is set to 16.5 mm to 19 mm. By setting the FLOW value in this way, the curable composition is easily leveled, and the emission observation surface of the wavelength conversion member formed on the upper surface of the LED chip 103 becomes a smooth surface. According to the forming method of the present invention, it is possible to easily dispose curable compositions having different physical properties (rheology) on the side surface and the upper surface of the LED chip. That is, a curable composition that does not cause sagging can be applied to the side surface of the LED chip, and a curable composition that can be easily leveled can be applied to the upper surface side of the LED chip. Therefore, a wavelength conversion member that covers all directions of the LED chip 103 with a uniform film thickness can be obtained, and a light emitting device with little change in chromaticity depending on the light emission observation direction can be obtained.

  Step 4. The metal mask is removed and left for a predetermined time until the surface on the light emission observation surface side of the curable composition disposed on the upper surface of the LED chip 103 is leveled and becomes a smooth surface.

  Step 5. The curable composition disposed on the side surface and the upper surface of the LED chip 103 is cured at 150 ° C. for 1 hr to obtain a wavelength conversion member having a layer thickness of 70 μm to 80 μm.

  The wavelength conversion member formed according to the present embodiment covers the light emission observation surface side of the LED chip 103 with a substantially uniform film thickness, and there is no change in chromaticity even if the light emission observation direction of the light emitting device is different. . Therefore, the light-emitting device in the present embodiment is a light-emitting device having excellent optical characteristics in addition to the effects in the other embodiments described above.

  In general, the larger the particle size, the higher the luminance of the particulate phosphor. However, when the particle size of the particulate phosphor is increased, the phosphor distribution becomes uneven due to sedimentation due to the weight of the phosphor. Cheap. In particular, the curable composition disposed in the side surface direction of the light-emitting element tends to cause the phosphor contained therein to be unevenly distributed, resulting in a light-emitting device having different chromaticity depending on each light emission observation direction.

In the present invention, particulate phosphors having different particle diameters can be contained in the curable composition for disposing on the side surface side of the LED chip 103 and the curable composition for disposing on the upper surface side, respectively. . Thereby, it is possible to easily form a wavelength conversion member containing phosphors having different particle sizes on the side surface and the upper surface of the LED chip 103. Therefore, in this example, in the formation method of Example 8 above, the YAG phosphor (Y _0.8 Gd _0.2 ) ₃ Al ₅ O ₁₂ : Ce contained in the wavelength conversion member in the side surface direction of the LED chip 103. The center particle size of YAG phosphor (Y _0.8 Gd _0.2 ) ₃ Al ₅ O ₁₂ : Ce contained in the wavelength conversion member in the main surface direction of the LED chip 103 is set to 8.6 μm. Is 20 μm. Thus, by making the center particle size of the phosphor contained in the wavelength conversion member in the main surface direction of the LED chip 103 larger than the particle size of the phosphor contained in the wavelength conversion member in the side surface direction of the LED chip 103 In the side surface direction of the LED chip, the phosphor is uniformly distributed in the direction along the side surface, and in the upper surface direction of the LED chip, the phosphor having a large particle size may be distributed in the direction along the upper surface. it can. Therefore, according to the present embodiment, the luminance in the main surface direction of the LED chip 103 can be improved, and a light emitting device with little change in chromaticity depending on the emission observation direction can be obtained.

  Since the light emitting device according to the present invention is excellent in temperature characteristics and optical characteristics, it can be used for in-vehicle lighting such as indoor lighting and car headlights that require high luminance light emission.

FIG. 1 is a schematic cross-sectional view of a light emitting device according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of a light emitting device according to an embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of a light emitting device according to an embodiment of the present invention. FIG. 4 is a schematic cross-sectional view of a light emitting device according to an embodiment of the present invention. FIG. 5 is a schematic cross-sectional view of a light emitting device according to an example of the present invention. FIG. 6 is a schematic cross-sectional view of a light emitting device according to an example of the present invention. FIG. 7 is a schematic top view of a light emitting device according to an embodiment of the present invention. FIG. 8 is a schematic cross-sectional view of a light emitting device according to an embodiment of the present invention. FIG. 9 is a perspective view schematically showing a method for forming a light emitting device according to an embodiment of the present invention. FIG. 10 is a perspective view schematically showing a method for forming a wavelength conversion member according to an embodiment of the present invention. FIG. 11 is a perspective view schematically showing a method for forming a wavelength conversion member according to an embodiment of the present invention. FIG. 12 is a cross-sectional view schematically showing a method for forming a wavelength conversion member according to an embodiment of the present invention. FIG. 13 is a diagram showing optical characteristics of the light emitting devices of one example and a comparative example of the present invention. FIG. 14 is a cross-sectional view schematically showing a method for forming a wavelength conversion member according to an embodiment of the present invention. FIG. 15: is sectional drawing which shows typically the formation method of the wavelength conversion member concerning one Example of this invention. FIG. 16: is sectional drawing which shows typically the formation method of the wavelength conversion member concerning one Example of this invention. FIG. 17: is sectional drawing which shows typically the formation method of the wavelength conversion member concerning one Example of this invention. FIG. 18 is a cross-sectional view schematically showing a method for forming a wavelength conversion member according to an embodiment of the present invention.

Explanation of symbols

101 ... support substrate 102 ... bump 103 ... LED chips 104, 104a, 104b ... first wavelength conversion member 105, 105a, 105b ... second wavelength conversion member 106 ... fluorescence Substance 107 ... Sealing member 201, 203 ... Curable composition 202 ... Dispenser 204 ... Screen plate 205 ... Squeegee 206 ... Underfill material 207 ... Conductive pattern 208 ... · P-side pedestal electrode 209 ··· n-side pedestal electrode 210 ··· translucent substrate 211 ··· diffusion electrode 212 ··· conductive wire 213 ··· package 214 ··· concave portion 215 ··· lead Electrode 216... Lens 217... Metal substrate 218... Light emitting element having wavelength conversion member

Claims (14)

A light-emitting device comprising: a light-emitting element having a pair of positive and negative electrodes on the same surface; a support substrate having a conductive pattern to which the electrodes are bonded via a conductive member; and a wavelength conversion member containing a fluorescent material. And
The wavelength conversion member is a first wavelength conversion member disposed in a side surface direction of the light emitting element, and a second wavelength conversion member that covers the main surface of the light emitting element separately from the first wavelength conversion member. And consists of
The light emitting device characterized in that the central particle diameter of the fluorescent material contained in the second wavelength conversion member is larger than the central particle size of the fluorescent material contained in the first wavelength conversion member.   The light emitting device according to claim 1, wherein the first wavelength conversion member is separated from the conductive member.   The light emitting device according to claim 1, wherein at least a part of the first wavelength conversion member is separated from the support substrate.   The light emitting device according to claim 3, wherein the first wavelength conversion member is separated from the support substrate through an underfill.   The light emitting device according to any one of claims 1 to 4, wherein a sealing member is disposed on the second wavelength conversion member.   The light emitting device according to claim 5, wherein the sealing member is positioned by an upper end portion of a first wavelength conversion member protruding from a plane including a main surface of the light emitting element.   The light emitting device according to claim 5, wherein the sealing member has a convex lens shape.   The light emitting device according to any one of claims 1 to 7, wherein the first wavelength conversion member or the second wavelength conversion member includes the fluorescent material and an inorganic member. The fluorescent material includes Al and at least one element selected from Y, Lu, Sc, La, Gd, Tb, Eu, Ga, In and Sm, and at least one element selected from rare earth elements Phosphor activated by
Or at least one element selected from C, Si, Ge, Sn, Ti, Zr, and Hf, and at least one element selected from Be, Mg, Ca, Sr, Ba, and Zn. A phosphor activated by at least one element selected from rare earth elements,
The light emitting device according to claim 1, wherein the light emitting device is at least one phosphor selected from the group consisting of:   The first wavelength conversion member has an upper end portion protruding from a plane including a main surface of the light emitting element, and the second wavelength conversion member covers at least a part of the upper end portion. The light emitting device according to any one of 9. In a method for forming a light emitting device comprising: a light emitting element; a support substrate on which the light emitting element is disposed; and a wavelength conversion member containing a fluorescent material.
A first step of supplying a mixture of a fluorescent substance and a binder for fixing the fluorescent substance along the outer periphery of the light emitting element;
A second step of positioning the mixture as a barrier and supplying a mixture of a fluorescent substance and a binder to the main surface side of the light emitting element;
And a third step of curing at least one of the mixture.   The method for forming a light emitting device according to claim 11, wherein the mixture supplied in the first step is cured before the second step.   13. The light emitting device according to claim 11, wherein the method for forming the light emitting device includes a step of bonding an electrode of the light emitting element to a conductive pattern of a support substrate via a conductive member before the first step. Forming method.   The center particle diameter of the fluorescent material in the mixture supplied by the second step is larger than the center particle size of the fluorescent material in the mixture supplied by the first step. A method for forming a light-emitting device according to 1.

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