JP2004221536A - Light emitting element and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting element and a manufacturing method thereof, where the light emitting element of high brightness and emission efficiency which is appropriate for uniformity and miniaturization with a integrally formed phosphor layer is manufactured at a high yield. <P>SOLUTION: In a process (a), a single blue LED wafer 11 is prepared where a light emitting layer 19 for a plurality of light emitting elements (blue LED chip: the size of each is smaller than a conventional blue LED chip) is formed on a sapphire substrate 10. In a process (b), a groove of specified form (side surface of chip) is formed to improve the emission efficiency of each light emitting element. A phosphor layer 14 is formed for emitting a complementary color that complements blue light in processes (c) and (d). After chromaticity inspection in a process (e), the border between the light emitting elements is cut (dicing) by a cutting tool 25 in a process (f). <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a light-emitting device and a light-emitting device, and more particularly to a method in which white light is emitted to the outside via a phosphor layer from a light-emitting layer having a diode configuration in which a semiconductor film is stacked on a transparent crystal substrate made of sapphire or the like. And a method of manufacturing a light emitting element (light emitting diode element).

  In recent years, gallium nitride-based (GaN-based) compound semiconductors such as GaN, GaAlN, InGaN, and InAlGaN in which a group III element such as Ga (gallium), Al (aluminum), and In (indium) are combined have been used for visible light emitting devices and the like. For example, as an example of a conventional light emitting diode (a light emitting device using such a light emitting diode), its basic structure is described in detail below. Patent Document 1).

  In this case, for example, as shown in FIG. 7 (details will be given to the following literature and the like), in this type of light emitting diode (light emitting device) 100, the blue light from the diode element (blue LED chip) 90 is replaced by the complementary color light. The light is synthesized (mixed and converted) through the phosphor layer 93 for emitting light, and is emitted to the outside as white light. In this case, an insulating sapphire substrate is generally used as the crystal substrate 89 for growing the semiconductor film, and Si (conductive) is used so that the electrode from the blue LED chip 90 can be taken out (electrically conductive). It is mounted (flip-chip mounted) on a sub-mount member (zener diode) 94 made of a silicon (substrate) substrate by a flip-chip method (for example, refer to Patent Document 2 below for a manufacturing method (manufacturing flow) for this). For the surface grinding, see Patent Document 3 below).

On the other hand, in parallel with these developments on the light emitting diode side, the development of grinding and cutting technology has been observed (for example, see Patent Documents 4 to 6).
Japanese Patent No. 3257455 JP 2001-15817 A JP-A-2002-158377 JP-A-11-156724 JP-A-11-165261 JP 2000-117641 A

  By the way, for example, in the conventional method of manufacturing a white light emitting diode shown in FIG. 8 (details are given to the above-mentioned document (particularly, Patent Document 2)), first, each single unit of the blue LED chip 90 using sapphire as a substrate is prepared. Then, on the Si wafer 92, bumps 91 for connecting to the electrodes of each blue LED chip 90 are formed (step (a)), flip-chip mounted and joined (step (b)), and the upper surface (substrate) is formed. Side) is polished by a polishing tool 95 to make it flat (uniform) (step (c)), and a phosphor material is screen-printed on its upper surface and side surfaces to obtain a plurality of white light emitting diodes having a phosphor layer 93. (Step (d)).

  Next, the upper surfaces of the plurality of white light emitting diodes are polished with a polishing tool 96 to be uniform (step (e)), and the white light emitting diodes are illuminated and light emitted from the upper surface is subjected to chromaticity through a microscope 97. The chromaticity is inspected by inputting to the measuring device 98 (step (f)), and the boundary of each white light emitting diode is cut (diced) using a cutting tool (dicer) 99 to obtain individual white light emitting diodes. (Step (g)), a final inspection is performed (Step (h): The figure shows one completed white light emitting diode 100).

  That is, in the above-described conventional manufacturing method, a complicated and troublesome process is required as described above only for the post-process after each single unit of the blue LED chip 90 is prepared. It also contributed to the hindrance of improvement. Therefore, in the following, the background of adopting the above-described manufacturing method will be examined.

  First, the blue LED chip 90 is configured using a sapphire substrate 89, but it is difficult to make the size and shape of the sapphire substrate uniform with the conventional cutting technology and processing accuracy that was premised. There was a problem that the yield was poor.

  In other words, the cutting portion (blade, etc.) of the cutting tool (dicer, etc.) is worn shortly after one cutting (grooving, dicing, etc.) and becomes unusable. In addition to processing methods such as polishing and cutting, sapphire substrates with uniform shapes, characteristics, sizes, etc. were used because they used a processing method similar to the form of cutting partially after inserting scribe lines. It is difficult to arrange blue LED chips using the above. Of course, due to the roughness of the processing accuracy, it is difficult to consider (examine) a method of cutting (full dicing) after forming a plurality of white light emitting diodes on a wafer made of sapphire. Was in

  Therefore, as a result, the above-described manufacturing method capable of collecting only a plurality of blue LED chips 90 within the predetermined processing accuracy and performing a subsequent post-process is adopted, and the complexity further hinders the improvement of the yield. It was a vicious cycle that contributed.

  However, on the other hand, as described above, the development of cutting technology and the like has also been observed, and the applicant of the present application has applied the above-mentioned technology (see Patent Documents 4 to 6) to provide a porous structure that is sharp and wears well. It is possible to develop a small cutting part (such as a blade) and a cutting tool (such as a dicer) having the same, and it is possible to use this to grind and cut (such as dicing) a sapphire substrate with small size and high accuracy. It is possible to infer (conclude) that there is something. Similar conclusions were obtained for a SiC substrate and a GaN substrate, which were difficult to grind or process like the sapphire substrate.

  That is, the present invention has been made by focusing on this point (development of processing technology such as grinding), and the present invention has a structure in which a phosphor layer is integrally formed, which is suitable for uniformity, and has a high luminance and luminous efficiency. It is an object of the present invention to provide a method for manufacturing a light-emitting element and a light-emitting element which can be manufactured at a high yield by simplification of a manufacturing process.

  The (first) method for manufacturing a light-emitting element of the present invention is a method of combining blue light from a light-emitting layer formed by laminating a semiconductor film on a light-transmitting crystal substrate and complementary light through a phosphor layer. A method for manufacturing a light emitting element of a type that emits light as white light to the outside, wherein the light emitting layers corresponding to a plurality of the light emitting elements are formed on the translucent crystal substrate. A preparing step of preparing a blue LED wafer, and applying and curing a phosphor for the complementary color light on the upper surface of the blue LED wafer on the side opposite to the light emitting layer to form the phosphor layer A layer forming step; and a cutting step of cutting a boundary between the plurality of light emitting elements on the blue LED wafer.

  In this manufacturing method, first, a blue LED wafer in which light emitting layers corresponding to a plurality of light emitting elements are formed on a translucent crystal substrate is prepared. That is, a blue LED wafer on which a light emitting layer that becomes a plurality of LED chips (blue light emitting diode elements) when divided (diced) is prepared is prepared. Here, each LED chip can be manufactured to a smaller chip size (can be downsized) with the improvement in processing accuracy due to the development of cutting tools and the like. Next, this wafer is processed as it is (ie, as a translucent crystal substrate), and batch processing for forming a phosphor layer is performed, and boundaries between a plurality of light emitting elements (between LED chips) are formed. By cutting (dicing) with high accuracy, a plurality of white light emitting elements (white light emitting diodes) can be obtained. Accordingly, the shape, characteristics, size, and the like of the light-emitting element can be made uniform (uniformity: hereinafter, including uniform miniaturization), and luminance and luminous efficiency can be increased. Further, since it can be formed integrally with a phosphor for emitting white light and a submount member (or a submount element) conventionally required is not required, it is suitable for further uniformity and miniaturization. Further, the process can be simplified, the production can be performed at a high yield, and the cost can be reduced. That is, it is possible to manufacture a light-emitting element in which a phosphor layer for white light emission is integrally formed and has uniform luminance and high luminous efficiency with a high yield by simplifying the manufacturing process. In this case, the chromaticity of the emission color can be adjusted by cutting the phosphor layer or the translucent crystal substrate, and the phosphor layer can recover from the cutting. In addition, a sapphire substrate, a SiC substrate, a GaN substrate, or the like (hereinafter, “sapphire substrate or the like”) can be used as the translucent crystal substrate in this case, and if it is blue light, it does not deteriorate even with an epoxy resin or a silicon resin. Therefore, these can be used as a binder for a resin-based phosphor (hereinafter, “resin-based binder”).

  Further, in the above-described manufacturing method, the entire surface of the light-emitting surface through the light-transmitting crystal substrate for emitting light from the light-emitting layer corresponding to the light-emitting element to the outside is set as a light-emitting region, and the white light is added and mixed. A plurality of light-emitting sharing regions each emitting its own shared color for synthesis are assigned in advance in the light-emitting region, and in the phosphor layer forming step, each shared light-emitting region emits each shared color. It is preferable to form a shared phosphor layer for the purpose.

  In this manufacturing method, a light-emission sharing region is allocated in the entire light-emission region, and a shared phosphor layer for emitting a light emission color shared by each light-emission sharing region is formed. By adjusting the area (emission area) of the region and the chromaticity of the shared phosphor layer laminated on each part, it is easy to fine-tune the addition and mixing of the (emission) colors assigned to each region, and to achieve ideal white light. There are advantages such as easy access.

  Further, in the above-described manufacturing method, the plurality of emission sharing regions include the blue light emission sharing region, and in the phosphor layer forming step, the shared phosphor is formed with respect to the blue light emission sharing region. Preferably, the formation of the layer is omitted.

  In this manufacturing method, the emission sharing region includes the emission sharing region of blue light, but since the formation of the sharing phosphor layer is omitted for the emission sharing region of blue light, the region without the phosphor layer, That is, a part of the light emitting surface on the translucent crystal substrate is left exposed, and the light emitting layer is a blue light emission sharing region where the blue light from the light emitting layer is emitted as it is (only through the inside of the substrate). That is, the emission sharing region of blue light can be easily formed simply by omitting the formation of the phosphor layer.

  Further, in each of the manufacturing methods in which the above-mentioned light emission sharing region is defined, as an intermediate step between the preparation step and the phosphor layer forming step, the entire surface of the light emission surface is subdivided corresponding to the plurality of light emission sharing regions. It is preferable that the method further includes a subdivided groove forming step of forming a subdivided groove by grinding.

  In this manufacturing method, since the subdivision grooves for subdividing the entire light emitting surface corresponding to the light emission sharing region are formed by grinding, the shape and area of each groove, the light emission area of each light emission sharing region, or stacked on each part By adjusting the chromaticity and the like of the shared phosphor layer, it is easy to finely adjust the additive color mixture of the emission colors assigned to each region, and it is easy to approach an ideal white light. In addition, since the subdivision grooves are formed, the total reflection of the light emitted from the inside of the substrate to the outside to the inside at the boundary surface can be suppressed (reduced), and further, the luminous efficiency can be improved. .

  Further, in each of the above-described manufacturing methods, as an intermediate step between the preparing step and the phosphor layer forming step, the light-emitting element for emitting light from the light-emitting layer to the outside may be provided on the light-transmitting crystal substrate. It is preferable that a part of the light emitting surface further includes a diffuse reflection portion forming step of forming a diffuse reflection portion for suppressing total reflection.

  In this manufacturing method, the irregular reflection portion for suppressing total reflection is formed on a part of the light emitting surface on the translucent crystal substrate. Can be suppressed, and the luminous efficiency to the outside can be improved.

  In each of the above-described manufacturing methods, the phosphor layer forming step preferably includes a polishing step of polishing an upper surface of the phosphor layer.

  In this manufacturing method, the thickness of the phosphor layer is adjusted so as to be uniform to the target thickness, and uneven light emission from the upper surface of the phosphor layer is eliminated, whereby the luminous efficiency can be increased. Further, the chromaticity can be adjusted by polishing.

  In each of the above-described manufacturing methods, as an intermediate step between the preparing step and the phosphor layer forming step, a groove is formed by grinding a boundary between the plurality of light emitting elements on the blue LED wafer. Preferably, the method further includes a groove grinding step of forming a side surface of the light emitting element for improving luminous efficiency. In the phosphor layer forming step, it is preferable that the phosphor layer is also formed in the groove.

  In this manufacturing method, by providing the groove that becomes the side surface, it is possible to make the area (light emission area) that finally emits white light up to the part that becomes the side surface of each light-emitting element, and a plurality of each light-emitting element in each wafer unit. The light-emitting area of the light-emitting element can be increased, and each luminous efficiency can be uniformly increased. Further, the light extraction efficiency when light is extracted from the translucent crystal substrate having a high refractive index to a layer (phosphor layer) having a low refractive index is also improved. In this case, it is preferable that the groove is ground into a curved surface (curved cross section) having a circular arc or a U-shaped cross section so as to suppress total internal reflection and improve luminous efficiency.

  In each of the above-described manufacturing methods, as a step after the phosphor layer forming step, after each of the plurality of light emitting elements emits light, the chromaticity of light emitted from the upper surface of the phosphor layer is adjusted. It is preferable to further include an inspection step of inspecting.

  In this manufacturing method, the chromaticity of light emission of a plurality of light emitting elements per wafer can be inspected at an early stage, and if there is a defect, for example, the phosphor layer (or the transparent crystal substrate side) is cut and the phosphor layer is cut. This makes it possible to start over before the formation process or to exclude the post-process as a defective product, so that the light-emitting element can be manufactured uniformly and with high quality, the yield can be improved, and the manufacturing efficiency can be improved.

  In each of the above-described manufacturing methods, it is preferable that the preparing step, the phosphor layer forming step, and the cutting step are performed in this order.

  In this manufacturing method, a plurality of white light-emitting elements for each wafer can be manufactured by performing the steps in a standard process order.

  In each of the above-described manufacturing methods, it is preferable that the cutting step is performed before the phosphor layer forming step.

  According to this manufacturing method, even when the standard process sequence needs to be changed, a plurality of light emitting elements per wafer can be manufactured flexibly. Further, even if a defect such as accuracy occurs in a cutting step for cutting the boundary between light emitting elements, there is an advantage that it is possible to exclude this as a defective product at an early stage.

  Further, in the above-described manufacturing method, it is preferable that the method further includes, in place of the cutting step, a bending step of cutting by cutting a boundary between the plurality of light emitting elements on the blue LED wafer.

  In this manufacturing method, instead of the cutting step (full dicing or the like) before the formation of the phosphor layer, the boundary between the plurality of light emitting elements on the LED wafer is cut (cut) so that the full dicing or the like is performed. As in the case of performing the above, a plurality of light emitting elements per wafer can be manufactured, and even if a defect such as the cutting accuracy occurs, in addition to the above advantage that it can be excluded as a defective product at an early stage, There are advantages such as the time required for cutting by a cutting tool (dicer or the like) and the abrasion of the cutting part (blade or the like) due to the time. Note that, in this case, the cutting step may be performed after a score line (scribe line) is formed at the boundary between the issuing elements by a dicer or the like.

  Further, another (second) method for manufacturing a light-emitting element of the present invention is that ultraviolet light from a light-emitting layer formed by laminating a semiconductor film on a translucent crystal substrate is externally transmitted through a phosphor layer. A method for manufacturing a light-emitting element for manufacturing a light-emitting element of a type that emits light, comprising preparing an ultraviolet LED wafer in which the light-emitting layers corresponding to a plurality of the light-emitting elements are formed on the translucent crystal substrate. And the three primary colors of R (red), G (green) and B (blue) for converting the ultraviolet light into white light are provided on the upper surface of the ultraviolet LED wafer on the side opposite to the light emitting layer. Applying and curing a phosphor of any one of the primary colors to form a phosphor layer for one of the primary colors; and forming the plurality of light-emitting portions on the ultraviolet LED wafer. A cutting step of cutting a boundary between the elements. .

  Also in this manufacturing method, as in the above-described (first) manufacturing method, a plurality of LED chips (here, ultraviolet light emitting elements) are provided on a light-transmitting crystal substrate such as a sapphire substrate so as to be smaller than before. An ultraviolet LED wafer on which a light emitting layer serving as a diode element is formed is prepared, processed as it is, and subjected to collective processing for forming a phosphor layer. Here, the phosphor layer is at least one of the three primary colors of RGB. That is, the color of light emitted through the phosphor layer of any one of the primary colors may be used as it is as the color of the light-emitting element. A light emitting device supplemented by molding (transfer molding) by a similar transfer molding method can also be used. However, if phosphor layers for three primary colors are used, a white light emitting device can be manufactured as described later. Here, the boundaries between the plurality of light emitting elements (LED chips) are cut with high precision to obtain a plurality of light emitting elements. This makes it possible to manufacture a light-emitting element (light-emitting diode) which is formed integrally with the phosphor layer, is suitable for uniformity, and has high luminance and high luminous efficiency with a high yield. Since the phosphor layer in this case is for ultraviolet light, a binder of a glass-based phosphor such as glass containing silicon oxide or the like as a main component that does not deteriorate even with ultraviolet light (hereinafter, “glass-based binder”) is used. Use is preferred.

  In the above-described manufacturing method, it is preferable that the individual phosphor layer forming step includes a removing step of removing excess phosphor cured on the upper surface of the ultraviolet LED wafer.

  In this manufacturing method, since the excess phosphor is removed, the thickness of the phosphor layer can be made uniform, and the emission unevenness can be suppressed.

  In each of the above-described manufacturing methods, as an intermediate step between the preparing step and the individual phosphor layer forming step, a groove is formed by grinding a boundary between the plurality of light emitting elements on the ultraviolet LED wafer. Preferably, the method further includes a groove grinding step of forming a side surface of the light emitting element for improving luminous efficiency. In the individual phosphor layer forming step, the phosphor layer is preferably formed also in the groove.

  In this manufacturing method, by providing grooves serving as side surfaces, the light emitting area of each of the plurality of light emitting elements in each wafer unit is increased, and the light extraction efficiency from the translucent crystal substrate is improved, whereby each Luminous efficiency can be uniformly increased. In this case as well, a curved (cross-sectionally curved) groove is preferable so that the luminous efficiency can be further improved.

  In each of the above-described manufacturing methods, it is preferable that the preparing step, the individual phosphor layer forming step, and the cutting step are performed in this order.

  According to this manufacturing method, a plurality of light emitting elements for each wafer can be manufactured by performing them in a standard process order.

  In each of the above-described manufacturing methods, it is preferable that the cutting step is performed before the individual phosphor layer forming step.

  In this manufacturing method, such a process enables flexible manufacturing even if the standard process sequence needs to be changed, and even if a defect such as accuracy occurs in the cutting process, it can be performed at an early stage. This can be excluded as defective.

  Further, in the above-described manufacturing method, it is preferable that a bending step of breaking the boundary between the plurality of light emitting elements on the ultraviolet LED wafer by cutting is provided instead of the cutting step.

  In this manufacturing method, the boundary between a plurality of light emitting elements on a wafer is broken and cut (divided) instead of full dicing before forming the phosphor layer. In addition, it is possible to manufacture a plurality of light emitting devices in wafer units, and to eliminate defects such as cutting accuracy at an early stage, and to save cutting time of cutting tools (dicers, etc.) and wear of cutting portions (blades, etc.). There are advantages. This folding step may be performed after a scribe line or the like is inserted between the emitting elements by a dicer or the like.

  Further, in each of the above-described manufacturing methods, as an intermediate step between the preparing step and the individual phosphor layer forming step, the light-transmitting crystal substrate corresponding to the light-emitting element for emitting light from the light-emitting layer to the outside is provided. It is preferable that a part of the light emitting surface further includes a diffuse reflection portion forming step of forming a diffuse reflection portion for suppressing total reflection.

  In this manufacturing method, the irregular reflection portion for suppressing total reflection is formed on a part of the light emitting surface on the translucent crystal substrate. Can be suppressed, and the luminous efficiency to the outside can be improved.

  In each of the above-mentioned manufacturing methods, it is preferable that the individual phosphor layer forming step is repeated by three layers of the three primary colors to form the three phosphor layers.

  In this manufacturing method, the phosphor layers of three colors (three layers) of a plurality of light emitting elements in a wafer unit can be formed only by repeating the same individual phosphor layer forming step, and three phosphor layers are formed in a stacked manner. Accordingly, a white light emitting element that converts ultraviolet light into white light and emits light can be easily and uniformly manufactured to a small size. In this case, the chromaticity of the emission color to the outside can be adjusted by the lamination specifications of the phosphor layers (the lamination thickness and the concentration of each layer, etc.).

  Further, in each of the above-described manufacturing methods, the entire surface of the light-emitting surface through the light-transmitting crystal substrate for emitting light from the light-emitting layer corresponding to the light-emitting element to the outside is set as a light-emitting region, and the white light is mixed by additive color mixing. A plurality of light-emission sharing regions that respectively emit their own colors in order to synthesize the colors, are allocated in advance in the light-emitting regions, and in the individual phosphor layer forming step, the one of the primary colors is shared by the self-emissions. It is preferable that a phosphor layer for emitting the assigned color be formed as a shared phosphor layer for the emission sharing region to be colored.

  In this manufacturing method, a light-emission sharing region is allocated in the entire light-emission region, and a shared phosphor layer for emitting a light emission color shared by each light-emission sharing region is formed. By adjusting the area (emission area) of the region and the chromaticity of the shared phosphor layer laminated on each part, it is easy to fine-tune the addition and mixing of the (emission) colors assigned to each region, and to achieve ideal white light. There are advantages such as easy access.

  In the above-described manufacturing method, it is preferable that the plurality of light-emission sharing regions include a light-emission sharing region for emitting three primary colors in which each of the three primary colors is its own color.

  In this manufacturing method, since the light-emission sharing region includes the light-emission sharing region for three-primary-color emission in which each primary color of the three primary colors is its own color, by forming them, the White light can be emitted by the combination of the emission colors described above, and the additive color mixture can be finely adjusted according to each light emission area and chromaticity to approximate an ideal white light.

  Further, in each of the manufacturing methods in which the above-mentioned light emission sharing region is defined, as an intermediate step between the preparation step and the individual phosphor layer forming step, the entire surface of the light emitting surface corresponds to the plurality of light emission sharing regions. It is preferable that the method further includes a subdivision groove forming step of forming a subdivision groove for subdivision by grinding.

  In this manufacturing method, since the subdivision groove for subdividing the entire light-emitting surface corresponding to the light-emission sharing region is formed by grinding, the shape and area of each groove, the light-emission area of each light-emission sharing region, and each shared phosphor By adjusting the chromaticity of the layer and the like, it is easy to finely adjust the additive color mixture of the emission colors, and it is advantageous in that it is easy to approach an ideal white light. In addition, since the subdivision grooves are formed, the total reflection of the light emitted from the inside of the substrate to the outside to the inside at the boundary surface can be suppressed (reduced), and further, the luminous efficiency can be improved. .

  Further, in the above-described manufacturing method including the step of forming the three phosphor layers, the phosphors of the three primary colors are mixed in advance instead of the step of forming the three phosphor layers. It is preferable to include a mixed phosphor layer forming step of applying and curing the mixed phosphor thus formed to form a phosphor layer of the mixed phosphor.

  According to this manufacturing method, a phosphor layer of a mixed phosphor that converts ultraviolet light into white light can be formed quickly and without unevenness, and a white light emitting element (white light emitting diode) can be obtained. In this case, the chromaticity of the emission color to the outside can be adjusted by the mixing ratio of the mixed phosphors (the mixing ratio of RGB).

  Further, in each of the manufacturing methods including the individual phosphor layer forming step described above, in the individual phosphor layer forming step, instead of applying the phosphor of any one of the primary colors, vapor deposition is performed, whereby Preferably, one phosphor layer of one primary color is formed.

  Further, in the manufacturing method including the above-described mixed phosphor layer forming step, in the mixed phosphor layer forming step, the deposition of the mixed phosphor is performed instead of the application of the mixed phosphor, whereby the phosphor of the mixed phosphor is formed. Preferably, a layer is formed.

  In these manufacturing methods, instead of coating the phosphor in the individual phosphor layer forming step or the mixed phosphor layer forming step, the phosphor layer is formed by vapor deposition of the phosphor. As in the case, in addition to the fact that the phosphor layer can be formed quickly and without unevenness, there are the advantages that the phosphor layer can be easily made thinner.

  Further, the (first) light-emitting element of the present invention is manufactured according to each of the above-described manufacturing methods, and emits light emitted from the light-emitting layer to the outside via the translucent crystal substrate and the phosphor layer. It is characterized by doing.

  Since this light-emitting element is manufactured according to each of the above-described manufacturing methods, a plurality of light-emitting elements are collectively formed on a wafer-by-wafer basis, and a phosphor layer is integrally formed, which is suitable for uniformization and has high luminance and high luminous efficiency. Can be manufactured with high yield.

  Further, another (second) light-emitting element of the present invention is formed by stacking a gallium nitride-based compound semiconductor film on a light-transmitting crystal substrate, and a light-emitting layer that emits blue light; An electrode surface formed having a p-side electrode and an n-side electrode as a surface on the light emitting layer side of the substrate, and a phosphor material for emitting light having a wavelength in a complementary color relationship with the blue light, A phosphor layer formed in the outer peripheral edge of the translucent crystal substrate and stacked on the top surface side opposite to the electrode surface, wherein the blue light emitted from the light emitting layer is transmitted through the phosphor layer. It is characterized in that white light is emitted to the outside by additive color mixture through the photonic crystal substrate and the phosphor layer.

  This light-emitting element has a light-emitting layer formed by laminating gallium nitride (GaN) -based compound semiconductor films, and a p-side electrode and an n-side electrode (that is, both electrodes of a diode) as surfaces on the light-emitting layer side. If flip chip mounting is performed with the electrode surface as a bonding surface, for example, a light-emitting layer is located immediately above a mounting surface serving as a lower surface, and a translucent crystal (for example, a sapphire substrate or the like) is placed thereon. Since the substrate is located, the light emitting element is configured as a type in which the top surface opposite to the electrode surface has a main light extraction surface. In this light-emitting element, the light-emitting layer emits blue light, and further includes a phosphor layer on the top surface for converting blue light into its complementary color (yellow-green) light, and transmits blue light from the light-emitting layer. Since light is emitted to the outside as white light by additive color mixing via the light-emitting crystal substrate and the phosphor layer, it is configured as a white light-emitting element. Since the phosphor layer in this case is formed on the top surface and inside the outer peripheral edge of the translucent crystal substrate, the chip size (planar area) can be the same as that of the translucent crystal substrate, such as a sapphire substrate. With the improvement in processing accuracy, a phosphor layer is integrally formed, so that a light emitting element suitable for uniformity and miniaturization and having high luminance and luminous efficiency can be manufactured at a high yield. In this case, the chromaticity of the emission color can be adjusted by cutting the phosphor layer or the translucent crystal substrate, and the phosphor layer can recover from the cutting.

  Further, still another (third) light-emitting element of the present invention is formed by stacking a gallium nitride-based compound semiconductor film on a light-transmitting crystal substrate, and emits ultraviolet light. An electrode surface formed having a p-side electrode and an n-side electrode as a surface on the light emitting layer side of the crystal substrate; and a top surface inside the outer peripheral edge of the translucent crystal substrate and opposite to the electrode surface. And a phosphor layer formed of phosphor materials of three primary colors of R (red), G (green) and B (blue) for converting the ultraviolet light into white light. The ultraviolet light emitted from the substrate is emitted to the outside as white light through the translucent crystal substrate and the phosphor layer.

  This light-emitting element has a light-emitting layer of a GaN-based compound semiconductor formed on a light-transmitting crystal substrate (eg, a sapphire substrate) and an electrode surface on the light-emitting layer side, similarly to the above-mentioned (second) light-emitting element. Therefore, the light emitting device is configured as a type of light emitting device having the top surface as the main light extraction surface. In this light-emitting element, the light-emitting layer emits ultraviolet light, and the three primary colors of R (red), G (green), and B (blue) for converting the ultraviolet light into white light are provided on the top surface side. The device further includes a phosphor layer made of a body material, and emits ultraviolet light from the light-emitting layer to the outside as white light through the translucent crystal substrate and the phosphor layer. In addition, since the phosphor layer is formed on the top surface and inside the outer peripheral edge of the translucent crystal substrate, the phosphor layer is integrally formed with the improvement of the processing accuracy of the sapphire substrate, etc. As a light emitting element which is suitable for miniaturization and miniaturization and has high luminance and luminous efficiency, it can be manufactured with high yield.

  In the above-described light emitting device, it is preferable that the phosphor layer is formed by laminating three phosphor layers of three primary colors each corresponding to one of the three primary colors.

  In this light-emitting element, ultraviolet light from the light-emitting layer can be emitted to the outside as white light through the phosphor layer having the RGB three-layer structure. In this case, the chromaticity of the emission color to the outside can be adjusted by the lamination specification of the phosphor layer.

  In the above-described light emitting device, it is preferable that the phosphor layer is formed by laminating a mixed phosphor obtained by previously mixing the phosphor materials of the three primary colors.

  In this light emitting device, the ultraviolet light from the light emitting layer can be emitted to the outside as white light through the phosphor layer of the mixed phosphor. In this case, the chromaticity of the emitted color to the outside can be adjusted by the mixing ratio of the mixed phosphor.

  Further, still another (fourth) light-emitting element of the present invention is formed by stacking a gallium nitride-based compound semiconductor film on a light-transmitting crystal substrate, and a light-emitting layer that emits blue light; An electrode surface formed having a p-side electrode and an n-side electrode as a surface on the light emitting layer side of the crystal substrate; and the blue light from the light emitting layer in the entire body surface of the translucent crystal substrate. A light-emitting element comprising: a light-emitting surface that emits light to the outside only through the light-transmitting crystal substrate; and a phosphor layer laminated on a part of the light-emitting surface, wherein light is emitted from the light-emitting layer. In order to emit the blue light to the outside as white light by addition and mixing through the translucent crystal substrate and the phosphor layer through the light-transmitting crystal substrate and the phosphor layer, the entire light-emitting surface is a light-emitting region, A plurality of light-emission sharing areas that emit light of their own colors are provided, Phosphor layers is characterized in that it is formed by laminating a phosphor material for emitting respective share colors for each emission allocated area.

  This light-emitting element has a light-emitting layer of a GaN-based compound semiconductor formed on a light-transmitting crystal substrate such as a sapphire substrate and an electrode surface on the light-emitting layer side, similarly to the above-described (second and third) light-emitting elements. Therefore, the light emitting device is configured as a type of light emitting device having the top surface as the main light extraction surface. In this light-emitting element, the entire surface of the light-emitting surface that emits blue light from the light-emitting layer to the outside of the light-transmitting crystal substrate is defined as a light-emitting region, and a plurality of light-emitting shared light sources that emit their own colors in the light-emitting region. A region is provided, and the phosphor layer is formed by laminating a phosphor material for emitting each of the assigned colors to each of the emission sharing regions. It is constituted as. In this case, since the light-emitting regions are divided and shared, the (light-emitting) color assigned to each region is adjusted by adjusting the area (light-emitting area) of each light-emitting shared region and the chromaticity of the phosphor layer laminated on each part. It is easy to fine-tune the additive color mixture, and to approach an ideal white light. Further, as in the case of the above-described light-emitting element, by improving the processing accuracy of a sapphire substrate or the like and integrally forming a phosphor layer, the light-emitting element can be manufactured at a high yield as a light-emitting element suitable for uniformity and miniaturization and having high luminance and luminous efficiency. .

  In the above-described light-emitting element, the plurality of light-emission sharing regions emit light of the blue light as their own assigned color, and light of a complementary color having a wavelength complementary to the blue light. And a light-emission sharing region for performing the operation.

  In this light-emitting element, the light-emission sharing region includes a light-emission sharing region for emitting blue light as a shared color and a light-emission sharing region for emitting complementary color light. Thus, white light can be emitted by synthesizing the emission colors from the respective emission sharing regions, and the additive color mixture can be finely adjusted according to each emission area and chromaticity to approximate an ideal white light.

  Further, still another (fifth) light-emitting element of the present invention is formed by stacking a gallium nitride-based compound semiconductor film on a light-transmitting crystal substrate, and emits ultraviolet light. An electrode surface formed having a p-side electrode and an n-side electrode as a surface on the light-emitting layer side of the crystal substrate; and the ultraviolet light from the light-emitting layer of the entire body surface of the translucent crystal substrate. A light-emitting element comprising: a light-emitting surface that emits light to the outside only through the light-transmitting crystal substrate; and a phosphor layer laminated on a part of the light-emitting surface, wherein light is emitted from the light-emitting layer. In order to emit the ultraviolet light to the outside as white light by adding and mixing through the translucent crystal substrate and the phosphor layer through the light-transmitting crystal substrate and the phosphor layer, the entire light-emitting surface is a light-emitting region, A plurality of light-emission sharing areas that emit light of their own colors are provided, Phosphor layers is characterized in that it is formed by laminating a phosphor material for emitting respective share colors for each emission allocated area.

  This light emitting element is configured as a light emitting element of a type having a top surface opposite to an electrode surface as a main light extraction surface, similarly to the above-described (second to fourth) light emitting elements. Also, in this light-emitting element, similarly to the above-described (fourth) light-emitting element, a plurality of light-emission sharing regions are provided with the entire light-emitting surface for the ultraviolet light from the light-emitting layer as the light-emitting region, and the phosphor layer Are formed by laminating phosphor materials of respective shared colors, and thus are configured as white light emitting elements that emit light to the outside as white light by additive color mixing. Also in this case, since the light-emitting regions are divided and shared, it is easy to fine-tune the additive color mixture by adjusting the light-emitting area of each light-emitting shared region and the chromaticity of the phosphor layer of each part, so that ideal white light Easy to approach. Further, by improving the processing accuracy and integrally forming the phosphor layer, a light-emitting element which is suitable for uniformity and miniaturization and has high luminance and luminous efficiency can be manufactured with high yield.

  In the above-described light-emitting element, the plurality of light-emission sharing regions include light of one of three primary colors of R (red), G (green), and B (blue) as their own colors or It is preferable to include a light-emission sharing region for emitting light obtained by adding and mixing two or more primary colors.

  In this light-emitting element, the light-emission shared region includes a light-emission shared region for emitting light of one of the three primary colors of RGB or light of an additive mixed color of two or more primary colors as the shared colors. In this way, white light can be emitted by combining the emission colors from the respective emission sharing regions, and the additive color mixture can be finely adjusted based on each emission area and chromaticity to approximate an ideal white light.

  In each of the light-emitting elements provided with the above-mentioned light-emission sharing regions, it is preferable that subdivision grooves are provided which subdivide the entire light-emitting surface corresponding to the plurality of light-emission sharing regions.

  In this light-emitting element, since subdivision grooves are provided to subdivide the entire light-emitting surface corresponding to the light-emission sharing region, the shape and area of each groove, the light-emission area of each light-emission sharing region, and the color of each shared phosphor layer By adjusting the degree, etc., it is easy to finely adjust the additive color mixture of the emission colors, and it is easy to approach an ideal white light. Further, total reflection of light emitted from the inside of the substrate to the outside to the inside at the boundary surface can be suppressed (reduced) by the provision of the subdivision groove, and the emission efficiency can be further improved.

  In each of the above-described light-emitting elements, it is preferable that a diffuse reflection portion for suppressing total reflection is provided on a part of a light-emitting surface of the translucent crystal substrate that emits light from the light-emitting layer to the outside.

  In this light-emitting element, a part of the light-emitting surface is provided with a diffuse reflection portion for suppressing total reflection, so that total reflection from the boundary surface of light traveling from the light-emitting layer to the outside through the inside of the substrate can be suppressed, The luminous efficiency to the outside can be improved.

  In each of the above-described light-emitting elements, the translucent crystal substrate is formed such that a top surface side opposite to the electrode surface is cut into a cross-sectional curved shape along an outer periphery thereof so as to conform to the shape. It is preferable that the phosphor layers are formed by lamination.

  In this light-emitting element, an area (light-emitting area) for emitting white light is obtained up to the corners of the top surface (portions that may be considered to be included on the side surfaces of each light-emitting element). The light-emitting area is increased, and the light-emitting efficiency is improved. Further, the light extraction efficiency when light is extracted from the translucent crystal substrate having a high refractive index to a layer (phosphor layer) having a low refractive index is also improved. Further, in this case, it is possible to straighten the corner, but in this case, since it has a curved cross section, it is possible to suppress the total reflection of the light to be emitted to the inside, and to further improve the luminous efficiency.

  As described above, according to the method for manufacturing a light emitting device of the present invention, an LED wafer in which a light emitting layer corresponding to a plurality of LED chips is formed on a translucent crystal substrate such as a sapphire substrate is prepared, and the wafer is kept in a wafer state. By processing, a plurality of light-emitting elements (LED chips: especially white light-emitting elements with integrated phosphor layers) can be manufactured collectively, so that the light-emitting elements (shape, characteristics, size, etc.) can be made uniform and compact. In addition, there is an effect that a submount element, which is indispensable in a conventional white composite light emitting element, becomes unnecessary. In addition, the light-emitting element of the present invention manufactured by the above-described method is a light-emitting element in which a phosphor layer is integrally formed, which is suitable for uniformity and miniaturization, and has high luminance and luminous efficiency. It is effective in that it can be manufactured at a high yield.

  Hereinafter, embodiments of a method for manufacturing a light emitting diode of the present invention will be described in detail in the order of first to sixth embodiments with reference to the drawings.

  First, as shown in FIG. 1, the method for manufacturing a light emitting diode according to the first embodiment includes steps (a) to (g), and a plurality of light emitting diodes 1 shown only in step (g) are collectively manufactured. Manufacturing method.

  As shown in FIG. 2A, the light-emitting diode 1 in this case emits blue light formed by laminating a gallium nitride-based (GaN-based) compound semiconductor film on a sapphire substrate 10 which is a light-transmitting crystal substrate. A light-emitting layer 19 that emits light, an electrode surface 15 having a p-side electrode 7 and an n-side electrode 8 and formed on the light-emitting layer 19 side, and light of a color (yellow-green) having a complementary color to blue ( And a phosphor layer 14 made of a phosphor material for emitting complementary color light) and formed on the surface (top surface) opposite to the electrode surface 15. The blue light emitted from the light emitting layer 19 is sapphire. A form in which blue light and complementary light are combined (additional color mixing) to emit light to the outside through the substrate 10 and the phosphor layer 14 as white light, and the main surface is the top surface opposite to the electrode surface, which is the mounting surface. This is a light emitting diode (light emitting element) of a type that is used as an extraction surface.

  Hereinafter, the steps (a) to (g) will be described with reference to FIG. 1 and FIG. 2B and 2C will be described later.

  First, in the step (a), a plurality of blue LED chips (blue light emitting diode elements: each size is smaller than that of the conventional blue LED chip shown in FIG. 7) on a sapphire substrate 10 of, for example, 2 inches (2 inch wafer). The light emitting layer 19 and its electrode surface 15 are formed, and the sapphire surface (top surface side) is polished by grinding the sapphire surface (top surface side) from, for example, a thickness of 300 μm to 100 μm. Is prepared (preparation step).

  Next, in the step (b), a groove 12 is formed using a cutting tool 21 at a position corresponding to the space between the blue LED chips on the top surface (a groove grinding step). The groove 12 is formed in a predetermined shape for improving the luminous efficiency of the light emitting diode 1 (for example, so that the sapphire substrate 10 finally becomes substantially trapezoidal in cross section (see FIGS. 1 (g) and 2)). In this case, since the cross-section is substantially trapezoidal, the area for emitting white light (light-emitting area) becomes larger than the top surface, and the light-emitting area can be finally set as the side surface of each light-emitting diode 1. The light emitting area of each of the plurality of light emitting diodes 1 can be increased, and each light emitting efficiency can be uniformly increased. Further, the light extraction efficiency when light is extracted from the refractive index (1.7) of the sapphire substrate having a high refractive index to the phosphor layer 14 having a low refractive index is also improved.

  If the groove in this case is, for example, V-shaped in cross section, the sapphire substrate 10 will eventually have a trapezoidal cross section, and the top surface will be straight-chamfered along its outer periphery. Then, it is ground into a curved surface (cross-sectional curved shape) having a circular arc or a U-shaped cross section. That is, the top surface is chamfered along the outer periphery into a curved surface (curved cross section), so that the light emitted to the outside from the boundary surface of the chamfered portion (part of the side surface) is the inside of the boundary surface. Total reflection to the light source can be suppressed, and the luminous efficiency can be further improved. Here, since the light emitting layer 19 is formed on the blue LED wafer 11 (sapphire substrate 10) with a thickness of about 10 μm or less, the groove 12 is formed to have a thickness of about 10 to 20 μm. Grind to a depth of ９０90 μm. Further, the cutting tool 21 is developed by applying, for example, the above-described technology such as grinding (see the above-mentioned Patent Documents 4 to 6 and the like). The cutting portion (blade) has a width of, for example, about 150 μm, It consists of ore or artificial gem particles having a hardness higher than sapphire such as sapphire or diamond.

  Next, in step (c), the phosphor paste 13 is poured into the upper surface of the blue LED wafer 11 including the groove 12, and then the upper surface of the paste 13 is flattened by a squeegee 26 or the like (phosphor application by screen printing ( Phosphor printing): This operation can be repeated as many times as necessary). Thereafter, the paste 13 is solidified (cured) by means such as heating (solidification step, curing step) to form the phosphor layer 14 (phosphor layer forming step). Here, it is a phosphor layer for blue light, and if it is blue light, it does not deteriorate even with an epoxy resin or a silicon resin, so a resin-based binder made of these can be used. In addition, this step (c) is capable of grinding the phosphor layer 14 and starting over (recovery), and can be used for chromaticity adjustment described later.

  Next, in the step (d), the upper surface of the phosphor layer 14 formed on the upper surface of the blue LED wafer 11 is polished using the polishing tool 22 so as to have a uniform thickness of a plurality of blue LED chips. Are polished (grinded) together (polishing step). By this step (d) and the next step (e), the chromaticity is accurately adjusted to a desired value, and the luminous efficiency can be increased by eliminating unevenness in light emission from the upper surface of the phosphor layer 14. In addition, this step (d) can be recovered in combination with the above step (c), and can be used for chromaticity adjustment described later. As the polishing tool 22, for example, the same type as the polishing tool 96 described above in FIG. 8 is used.

  Next, in the step (e), the polished blue LED wafer 11 is turned upside down, and the phosphor layer 14 is turned downward so that each light emitting layer 19 emits light as each blue light emitting element (blue LED chip). The chromaticity of the direct light emission from the light emitting layer 19 is inspected using the measuring tool 23, and the phosphor layer 14 is returned upward, and then the light emission from each light emitting layer 19 is similarly performed as each white light emitting element (white LED chip). Then, the chromaticity (here, the chromaticity as white light via the phosphor layer 14) is inspected (inspection step). According to this inspection, the chromaticity abnormality via the phosphor layer 14 is redone (recovered) from the grinding of the phosphor layer 14 (step (d)), and if the phosphor layer 14 is excessively ground, The chromaticity is adjusted from the phosphor layer step (c) or, if the specification of the phosphor is wrong, from the previous groove grinding (step (b)). If adjustment is still impossible, or if a chromaticity abnormality directly from the light emitting layer 19 is found, a mark is applied to the abnormal light emitting element (LED chip), etc. And remove it in the process after chip separation. In addition, the measurement of the chromaticity as white light can be inspected only by measuring with the phosphor layer 14 down, if the correlation is taken.

  Next, in step (f), the blue LED wafer 11 is placed on a UV tape or a weakly adhesive dicing tape (dicing sheet) 24 with the phosphor layer 14 facing upward, and the light emitting element (LED chip) is placed. Is cut (diced) using a cutting tool (dicer) 25 (cutting step, dicing step). As the dicer 25, a dicer having the same quality as the above-mentioned cutting tool 21 and having a cutting portion (blade) having a width of, for example, about 40 μm can be used. In this case, the phosphor layer 14 and the sapphire substrate 10 in the groove 12 are left. (10-20 μm) is diced (full dicing).

  Finally, in step (g), a final inspection is performed. One completed white light emitting diode (light emitting element) 1 shown in the drawing has a phosphor layer 14 formed integrally with the conventional general white light emitting diode (light emitting device) 100 shown in FIG. Since it is suitable for uniformity and miniaturization and has good light extraction efficiency from the sapphire substrate 10, luminance and luminous efficiency are higher than before.

  Of course, the light emitting diode 1 for white light has the phosphor layer 14 and the electrode surface 15 is exposed in a conductive manner. Therefore, it is necessary to further mount this on the Si substrate (such as the Zener diode 94). Instead, as in the case of the conventional general light emitting diode 100, flip chip mounting or the like may be directly performed on substrates of various applied devices as it is. Alternatively, the phosphor layer 14 side may be die-bonded with a transparent paste or the like with the electrode surface 15 facing up, and the p-side electrode 7 and the n-side electrode 8 may be connected to the lead portion of the device with a wire such as Au. In this case, a part of the p-side electrode 7 may have a transparent electrode specification.

  As described above, according to the present embodiment (first embodiment), if dicing is performed, a plurality of LED chips (blue light emitting diode elements: each size corresponds to a size smaller than a conventional blue LED chip) A blue LED wafer 11 having a light emitting layer 19 formed on a sapphire substrate 10 is prepared, and a phosphor layer 14 that emits light of a color having a complementary color with blue (complementary light) as one unit to be processed as it is. , A plurality of white light-emitting diodes (white light-emitting elements) 1 having a uniform size and high luminance and high luminous efficiency can be manufactured at once. In addition, the process can be simplified, the production can be performed at a high yield, and the cost can be reduced. In this case, the chromaticity of the emission color can be adjusted by cutting the phosphor layer or the sapphire substrate, and the phosphor layer can recover from the cutting.

  In the above-described embodiment, dicing is performed after the phosphor layer 14 is formed. However, dicing may be performed before the phosphor layer 14 is formed.

  Assuming that this case is the second embodiment, as shown in FIG. 3, following the same preparation step (a) and groove grinding step (b) as in the first embodiment, dicing is performed prior to the formation of the phosphor layer 14. The sheet is placed on a sheet 24 and diced (step (h) in FIG. 7: cutting step: similar to the step in which the phosphor layer 14 is not cut in step (f) in FIG. 1), and then the phosphor is screen-printed or the like. Is printed (coated) to form each phosphor layer 14 (step (i): similar to step (c) in FIG. 1), and the surface thereof is polished (step (j): step (d) in FIG. 1). )), Chromaticity measurement (inspection) is performed (step (h): similar to step (e) in FIG. 1), recovery is performed if necessary, and then the sapphire substrates 10 are separated from each other (grooves 12). ), Only the portion of the phosphor layer 14 remaining is diced (step (l): the fluorescent light is applied in step (f) of FIG. 1). Corresponds to the step of cutting only the layer 14), then performing final inspection (steps a in FIG. 1 (g)).

  As described above, even in the case where it is necessary to change the above-described standard process sequence in the first embodiment of FIG. 1 and the like, it is possible to flexibly cope with a plurality of light emitting elements per wafer. it can. Further, even if a defect such as accuracy occurs in a cutting step (step (h)) for cutting a boundary between light emitting elements, there is an advantage that it can be excluded as a defective product at an early stage.

  Further, instead of the above-mentioned full dicing (step (h)) before the formation of the phosphor layer 14, it is also possible to fold the emitting elements.

  Assuming that this case is the third embodiment, as shown in the figure, following the groove grinding step (b), the blade of the break tool 26 is strongly contacted from above or below (or from both above and below) ( (Pressing in), and pressing (breaking: breaking) between the sapphire substrates 10 (grooves 12) (breaking step: bending step) (step (m)) to perform the cutting step described above. Instead of (h), the space between the sapphire substrates 10 is cut. In this case, in the above-mentioned cutting step (h), after the scribe line (scribe line) is formed by the dicer 25 (in this case, a laser or the like) (shown by a dotted arrow), the folding step (m) is performed. You may go.

  In these cases, even if a defect such as accuracy occurs at the boundary between the light emitting elements, in addition to the above advantage that the defect can be excluded as a defective product at an early stage, in addition to the time required for cutting by the cutting tool (dicer) 25, Also, there is an advantage that wear of the cutting portion (blade) can be saved.

  In each of the above embodiments (first to third embodiments), the phosphor layer 14 is formed as shown in FIG. 2A, but as shown in FIG. The phosphor layer 14 may have a shape along the (shape of the top surface of the sapphire substrate 10) or the phosphor layer 14 on the top surface of the sapphire substrate 10 may be removed as shown in FIG. May be exposed. In these cases, steps (b) to (d) (or step (j)) and the like are devised so that the shape of each part such as the groove 12, the ratio (balance) of the light emitting area, the chromaticity of the phosphor layer 14, etc. Is adjusted, the white light can be approximated to an ideal white light.

  Further, in each of the embodiments described above, the sapphire substrate is used as the translucent crystal substrate. However, a SiC substrate, a GaN substrate, or the like can be used as well.

  Next, as shown in FIG. 4, the method for manufacturing a light-emitting diode according to the fourth embodiment includes steps (a) to (f). It is a manufacturing method for manufacturing.

  In this case, the light emitting diode 3 is formed by laminating a gallium nitride-based (GaN-based) compound semiconductor film on a translucent sapphire substrate 30, as shown in FIG. 5 (a) or (b). A light-emitting layer 39 that emits ultraviolet light, an electrode surface 35 having a p-side electrode 7 and an n-side electrode 8 and formed on the light-emitting layer 39 side, R (red), G (green), and B (blue) And an RGB three-layer phosphor layer 34 made of each of the three primary color phosphor materials, and is configured as a light-emitting diode (light-emitting element) having a top surface as a main light extraction surface.

  Here, the RGB three-layer phosphor layer 34 is formed by laminating three phosphor layers of three primary colors each corresponding to each of the three primary colors of RGB. Through the body layer 34, ultraviolet light from the light emitting layer 39 can be emitted to the outside as white light. In this case, the chromaticity of the emission color to the outside can be adjusted by the lamination specifications of the phosphor layers (thickness of the lamination of each layer and the like).

  Hereinafter, steps (a) to (f) will be described with reference to FIGS. 4 and 5. Steps (g) and (h) will be described later.

  First, in the step (a), a plurality of ultraviolet LED chips (each size is a conventional general ultraviolet) on the sapphire substrate 30 with the same size and surface finish as the blue LED wafer 11 of the first embodiment. A single ultraviolet LED wafer 31 on which a light emitting layer 39 and an electrode surface 35 thereof are formed (corresponding to a size smaller than the LED chip) is prepared (preparation step).

  Next, in the step (b), a groove 32 is formed at a position corresponding to the space between the ultraviolet LED chips by using the aforementioned cutting tool 21 in the same manner as in the first embodiment (a groove polishing step). The shape, cutting depth, and the like of the groove 32 are the same as those of the groove 12 of the first embodiment. The light emitting area of each of the plurality of light emitting diodes 3 in each wafer unit is increased, and the light from the sapphire substrate 30 is increased. This is for improving the extraction efficiency and uniformly improving each luminous efficiency.

  Next, in the step (c), the phosphor paste 33 for one of the three primary colors of RGB (one layer) is applied by screen printing on the upper surface of the ultraviolet LED wafer 31 including the groove 32 to be flattened. , This process can be redone as many times). Thereafter, the paste 33 is solidified (hardened) by means such as heating (individual phosphor layer forming step). Thereby, the cured layer of the phosphor paste 33 becomes a phosphor layer for one of the three primary colors (one layer). In this case, since the phosphor layer is for ultraviolet light, it is preferable to use a glass-based binder such as glass containing silicon oxide or the like as a main component that does not deteriorate even with ultraviolet light. In this step (c), the phosphor layer can be recovered by grinding the phosphor layer, and can be used for adjusting the chromaticity.

  Next, in the step (d), unnecessary (excess) phosphor paste 33 on the upper surface including the groove 32 (particularly in the groove 32) is removed using the cutting tool 21 (removal step). Thereby, the thickness of the phosphor layer can be made uniform, and the occurrence of uneven light emission can be suppressed.

  In the present embodiment (fourth embodiment), the above steps (c) and (d) are performed three times (for three colors and three layers) corresponding to the three primary colors of R, G and B. By repeating this, an RGB three-layer phosphor layer 34, which is a phosphor layer having a three-layer structure (see FIG. 5), is formed and is subjected to a subsequent step (step (e) and subsequent steps).

  Next, in the step (e), after the step of inspecting the chromaticity of light emission (not shown: similar to the step (e) of the first embodiment in FIG. 1), the ultraviolet LED wafer 31 is attached to the RGB3 The phosphor layer 34 is placed on the dicing sheet 24 so that the phosphor layer 34 faces upward, and the boundary between the light emitting elements (LED chips) is similarly set using the dicer 25 (the phosphor layer in the groove 32). 34 (about 10 to 20 μm of the sapphire substrate 30) is cut (full dicing) (cutting step).

  Finally, in the step (f), a final inspection is performed. Compared with the conventional white light emitting diode 100, the completed one white light emitting diode 3 shown in the drawing has an RGB three-layer structure phosphor layer 34 integrally formed, and is suitable for uniformity and miniaturization, and the sapphire substrate 10 Since the light extraction efficiency is high, the luminance and the light emission efficiency are higher than those of the conventional light emitting diode 100. Needless to say, flip chip mounting or the like may be directly performed as is the case with the light emitting diode 100, or may be mounted on the substrate of various applied devices via wire bonding.

  In the above-described example, the phosphor layer is the RGB three-layer phosphor layer 34, but the above-described manufacturing method can be realized if at least a light-emitting layer of at least one of the three primary colors RGB is formed. In other words, the light emission color via the phosphor layer of any one of the primary colors may be used as it is as the light emission color of the light emitting element. A light emitting device supplemented by transfer molding similar to that described above can also be used. However, as described above, if the phosphor layers for the three primary colors are formed, the phosphor layers are integrally formed, and a light-emitting element (light-emitting diode 3) suitable for uniformization and miniaturization and having high luminance and luminous efficiency is used. This is preferable because it can be manufactured with a high yield.

  Next, in the method for manufacturing a light emitting diode according to the fifth embodiment, instead of repeating the above-described steps (c) to (d) three times in the fourth embodiment, steps (g) to (H). Hereinafter, the steps (g) to (h) will be described.

  As shown in FIG. 4, first, in step (g), an RGB mixed phosphor tank 36 in which RGB mixed phosphors formed by mixing respective phosphors of the three primary colors of RGB are stored in a state of being dispersed in a liquid. The sapphire substrate 30 (UV LED wafer 31) having the groove 32 formed in the above-described step (b) is sunk, and the RGB mixed phosphor is deposited thereon and taken out. Here, this RGB mixed phosphor is formed by premixing phosphors for forming each of the phosphor layers of the three primary colors of RGB, and forms a mixed phosphor layer 37 that can convert ultraviolet light into white light. It is for. In this RGB mixed phosphor, low melting point glass particles serving as a binder are also put.

  Next, in step (h), the RGB mixed phosphor adhered to the electrode surface 35 of the sapphire substrate 30 (ultraviolet LED wafer 31) was removed, and the RGB mixed phosphor layer 37 in the upper surface and the groove 32 was removed by a predetermined amount. After the thickness is adjusted, it is cured by heat treatment, and thereafter, the above-described steps (e) and (f) are performed. Thereby, the RGB mixed phosphor layer 37 for converting ultraviolet light into white light can be formed quickly and without unevenness, and the light emitting diode (light emitting element) 3 for white light can be manufactured. In this case, the chromaticity of the emission color to the outside can be adjusted by the mixing ratio of the RGB mixed phosphor (mixing ratio of RGB).

  As described above, according to the above-described embodiments (the fourth and fifth embodiments), a plurality of ultraviolet LED chips (however, each size is smaller than a conventional ultraviolet LED chip) on the sapphire substrate 30. An ultraviolet LED wafer 31 on which a light-emitting layer 39 serving as a (corresponding) light-emitting layer 39 is formed is prepared, and as a unit of processing (one processing target), a phosphor layer of RGB three primary colors that converts ultraviolet light into white light (RGB three-layer structure) Batch processing for forming the phosphor layer 34 or the RGB mixed phosphor layer 37) is performed, and a plurality of white light emitting diodes (white light emitting elements) 3 can be manufactured at a time, and are uniform, small, and ultraviolet. Since light has higher energy intensity than blue light, a light-emitting diode (light-emitting element) having higher luminance and luminous efficiency can be manufactured with a high yield.

  In the above-described fourth or fifth embodiment, dicing is performed after the formation of the RGB three primary color phosphor layers (RGB three-layer phosphor layer 34 or RGB mixed phosphor layer 37). Similarly to the embodiment, before the phosphor layer is formed, the phosphor layer is placed on the dicing sheet 24 and subjected to full dicing (see step (h) in FIG. 3), and then the RGB three primary color phosphor layers are formed by screen printing or the like. Accordingly, even when the above-described standard process sequence needs to be changed, a plurality of light emitting elements per wafer can be manufactured flexibly. Further, even if a defect such as accuracy occurs in the cutting step between the light emitting elements, there is an advantage that it can be excluded as a defective product at an early stage.

  Similarly, instead of the above-mentioned full dicing before forming the phosphor layer or together with partial cutting, a bending step (see step (m) in FIG. 3) may be performed. In addition to the above-mentioned advantages that can be excluded, there are advantages such as saving of cutting time by the cutting tool and wear of the cutting portion (blade) thereof.

  In the above embodiment, the RGB three-layer phosphor layer 34 is formed by screen printing (fourth embodiment), and the RGB mixed phosphor layer 37 is formed by using the RGB mixed phosphor layer. (Fifth Embodiment) The RGB mixed phosphor layer 37 may be formed by performing screen printing with an RGB mixed phosphor paste, or a phosphor tank for each of the three primary colors of RGB is prepared, and is prepared. The phosphor layer 33 of each layer is formed by using the phosphor layer 33, and the phosphor layer 33 is repeated for three primary colors (three times) (that is, the steps (g) and (h) are repeated three times) to obtain an RGB three-layer phosphor layer. 34 can also be formed.

  In addition, instead of the above-described method using screen printing or a phosphor tank, a phosphor layer can be formed using a chemical vapor deposition method (CVD) using heat, plasma, light, or the like. Assuming that this is the sixth embodiment, in this case, as in the above-described fourth embodiment, vapor deposition is performed once for each of the RGB three primary color fluorescent layers 33 including a glass-based binder and the like, and only three primary colors are deposited. The above-described RGB three-layer phosphor layer 34 may be formed repeatedly, or, similarly to the above-described fifth embodiment, an RGB mixed phosphor containing a glass-based binder is prepared and vapor-deposited in advance. May be formed (the vapor deposition step (i) in FIG. 4).

  Further, in the above-described embodiments (the fourth to sixth embodiments) for ultraviolet light, a sapphire substrate is used as a translucent crystal substrate, but a SiC substrate, a GaN substrate, or the like can also be used.

  In each of the above embodiments (first to sixth embodiments), as shown in the bottom view of the wafer 11 or the wafer 31 in the preparation step (a) of FIG. 1 or FIG. The n-side electrode 8 is provided in the portion (region) corresponding to one quadrant and the p-side electrode 7 is provided in the other triangle (the portion (region) corresponding to the other three quadrants). Although the surface 35 is used, for example, as shown in the front sectional view and the bottom view of FIGS. , May be shared. Here, regardless of whether the light emitting diode is based on a blue LED (blue light emitting diode: blue light emitting element) or the light emitting diode based on ultraviolet LED (ultraviolet light emitting diode: ultraviolet light emitting element), a light emitting diode (light emitting diode) is representative of these. Element 5).

  Further, regarding the light emitting surface (light extraction surface) including the top surface and the side surface, in the light emitting diode (light emitting element) 1 of FIG. 2, the entire light emitting surface (light emitting region) 18 is a top surface portion mainly in charge of blue light. (Top surface region) 18a or 18c (top surface exposed region 18a or top phosphor region 18c) and a side surface portion (foot portion including a chamfered portion: side surface region) 18b mainly in charge of complementary color light. Light emission is roughly divided into two types of regions. In the light emitting diode (light emitting element) 3 in FIG. 5, the entire light emission is in charge of the entire light emitting region 38 without dividing the top surface region 38c and the side surface region 38b. However, light emission can be divided into smaller areas.

  For example, in the light-emitting diode 5 shown in FIGS. 6A and 6B, the sapphire substrate 50 has a curved top surface (cross-sectional curve) along its outer periphery, similarly to the light-emitting diodes 1 and 3 in FIGS. In addition to being chamfered (grinded) into a shape, a cross-shaped plane crossing at the center of the top surface so as to be a cross-sectional curve (semicircular cross-section (circular arc), cross-section substantially U-shaped, etc.) Grooves (cross grooves: subdivided grooves) are formed by grinding, so that the top surface region has a light emitting region (cross groove region: subdivided groove region) 58d through the cross-shaped groove and the remaining squares. The light-emitting device is further divided into four island portions (island regions) 58a or 58c (island exposed regions 58a or island phosphor regions 58c) to take charge (share).

  In this case, the entire light-emitting region 58 is subdivided into a side surface region 58b serving as a light-emission sharing region, a cross groove region 58d, and an island region 58a or 58c. By adjusting the area of the shared area (light emission area) or the chromaticity of the shared phosphor layer laminated on each part, it is easy to fine-tune the addition and mixing of (emission) colors assigned to each part (each area), which is ideal. There are advantages such as easy access to white light. Further, the total reflection of the light emitted from the inside of the substrate to the outside at the boundary surface thereof can be suppressed (reduced) by the formation of the groove such as the cross groove, and the luminous efficiency can be further improved. Joins.

  For example, if the light emitting diode 5 in FIG. 7A is a blue light emitting diode, if the island exposed region 58a is responsible for (light emission of) blue light and the other side surface region 58b and the cross groove region 58d are responsible for complementary color light, For example, as compared with the case of the light emitting diode 1 of FIG. 2, fine adjustment of additive color mixture is easy, and it is easy to approach an ideal white light because of the subdivision of the light emitting area. Can be improved. In this case, the complementary color of blue (yellow green) may be used as the shared color for both the side surface region 58b and the cross groove region 58d, or different colors may be shared between the side surface region 58b and the cross groove region 58d. However, the assignment may be determined so that the combination of the emission colors is blue complementary light (more precisely, the overall combination is white light).

  Similarly, when the light emitting diode 5 in FIG. 3B is an ultraviolet light emitting diode, for example, the side surface region 58b is responsible for red light (R), the cross groove region 58d is responsible for green light (G), and the island phosphor is used. If the region 58c is responsible for the blue light (B), fine adjustment of additive color mixture can be easily performed because the light-emitting region is subdivided, for example, compared to the case of the light-emitting diode 3 in FIG. It is easy to approach and the luminous efficiency can be improved.

  In the above-described light-emitting diode 5, although grooves for subdivision (subdivision grooves) are provided in a plane cross shape, various subdivisions such as a lattice shape (a mesh shape) and the like are conceivable. In addition, the step of forming such a subdivision groove (subdivision groove forming step) includes steps of forming a phosphor layer (step (c) in FIG. 1, step (i) in FIG. 3, and step in FIG. 6). A step before (c) or step (g) or step (i)), for example, a step before or after or simultaneously with a groove grinding step for forming a side surface (step (b) in FIGS. 1, 3, and 4) It may be implemented as Further, in this case, the formation of the phosphor layer (shared phosphor layer) for each light-emission sharing region is performed as a part of the above-described process for forming the phosphor layer or the same process as the above-described formation of the phosphor layer. What is necessary is just to repeat and implement. Further, since the above-described subdivision groove forming step is a step of subdividing the light emitting region (light emitting surface), it may be referred to as a light emitting region subdivision step or a light emitting surface subdivision step.

  In addition, when the light emitting region is subdivided, a phosphor layer is stacked in each region and assigned to each light emitting color. However, forming various grooves and the like in each part of the light emitting region makes it possible to subdivide the light emitting region. Even if it is not, it is effective in terms of suppressing total reflection and thereby improving luminous efficiency. Therefore, a groove may be formed for the purpose of suppressing total reflection without subdividing the light emitting region.

  For example, in the light emitting diode 6 of FIG. 3C, in addition to the chamfering grinding of the cross-section of the top surface of the sapphire substrate 60, a straight cut portion is parallel to a part (including the whole) of the top surface. A plurality of irregularly-reflected portions 60a are formed at predetermined intervals and in both the vertical and horizontal directions (that is, formed in a lattice shape) to induce diffused reflection. It is possible to prevent the total reflection of light traveling toward the (boundary surface with the outside) toward the inside on the top surface (boundary surface), thereby improving the luminous efficiency to the outside.

  Although the cross section of the cut portion is V-shaped in the illustrated example, it may be formed in a U-shape, an arc shape, or another shape (such as a curved shape). Further, the above-mentioned lattice-shaped cut portion may be a vertical or horizontal linear cut portion, and various types of irregularly-reflected portions such as a wave-shaped (curved) cut and the like may be used. Further, in the above-described example, the irregular reflection portion 60a is formed in the top surface region (top phosphor region) 68c, but may be formed in the side surface region 68b. Also, the light may be formed in the top surface exposed area (that is, the irregular reflection portion 60a is exposed). Also, the step of forming the irregular reflection portion (the irregular reflection portion forming step) may be performed at the same timing as the above-described subdivision groove forming step. Further, it can be used together with the formation of the subdivision groove, and the irregular reflection portion can be provided on the substrate surface corresponding to each subdivided light emission sharing region.

  As described above, various contrivances can be made on the electrode surface and the light emitting surface of the light emitting diode (light emitting element), and various contrivances can be made on the manufacturing method corresponding thereto. Of course, in addition to the above, the light emitting element and its manufacturing method can be appropriately changed without departing from the gist.

FIG. 5 is a sectional view illustrating the method of manufacturing the light-emitting device according to the first embodiment of the present invention, which illustrates the method. FIG. 2 is an explanatory diagram showing an example of the structure of various light emitting elements that can be manufactured by the manufacturing method of FIG. 1 and an image of emitting white light by blue light and its complementary color light. FIG. 6 is a sectional view illustrating the second and third embodiments according to the present invention, which is similar to FIG. FIG. 11 is a cross-sectional view illustrating the fourth to sixth embodiments according to the present invention, which is similar to FIG. FIG. 5 is an explanatory diagram showing an example of the structure of a light-emitting element manufactured by the manufacturing method of FIG. 4, and a three-layer phosphor layer with three primary colors of RGB and a mixed phosphor layer formed by mixing phosphors of each of RGB colors. FIG. 5 is an explanatory diagram showing another example of the structure of various light emitting elements that can be manufactured by the manufacturing methods of FIGS. It is a front sectional view showing an example of the structure of the white light emitting device using the conventional general light emitting element. It is sectional drawing according to process which shows an example of the manufacturing method of the conventional light emitting element.

Explanation of reference numerals

1, 3, 5, 6 ... Light-emitting diode 7 P-side electrode 8 N-side electrode 10, 30, 50, 60 ... Sapphire substrate 11 Blue LED wafer 12, 32 ... Groove 13, 33 ... Phosphor paste 14 Fluorescence Body layer 15, 35, 55 ... Electrode surface 19, 39, 59 ... Light emitting layer 21 Cutting tool 22 Polishing tool 23 Chromaticity measuring tool 24 Dicing sheet 25 Cutting tool (dicer)
31 UV LED wafer 34 RGB three-layer phosphor layer 36 RGB mixed phosphor tank 37 RGB mixed phosphor layer

Claims (37)

A light-emitting element that emits white light to the outside is manufactured by combining blue light from a light-emitting layer formed by laminating a semiconductor film on a light-transmitting crystal substrate and complementary light through a phosphor layer. A method of manufacturing a light emitting device for
A preparing step of preparing a blue LED wafer in which the light emitting layers corresponding to a plurality of the light emitting elements are formed on the translucent crystal substrate;
On the upper surface of the blue LED wafer opposite to the light emitting layer, a phosphor for the complementary color light is applied and cured, and a phosphor layer forming step of forming the phosphor layer,
A cutting step of cutting boundaries between the plurality of light emitting elements on the blue LED wafer;
A method for manufacturing a light emitting device, comprising: The entire surface of the light-emitting surface through the translucent crystal substrate for emitting light from the light-emitting layer corresponding to the light-emitting element to the outside is set as a light-emitting region, and each of the light-emitting devices shares its own light to combine the white light by additive color mixing. A plurality of light-emission sharing regions that emit colors are pre-assigned in the light-emitting region,
2. The method according to claim 1, wherein, in the phosphor layer forming step, a shared phosphor layer for emitting each of the shared colors is formed for each of the light-emitting shared regions. 3. The plurality of light emission sharing areas include the blue light emission sharing area,
The method according to claim 2, wherein, in the phosphor layer forming step, the formation of the shared phosphor layer in the emission sharing region of the blue light is omitted. As an intermediate step between the preparing step and the phosphor layer forming step,
4. The method according to claim 2, further comprising: forming a subdivided groove by grinding a subdivided groove for subdividing the entire surface of the light emitting surface corresponding to the plurality of light emission sharing regions. 5. A method for manufacturing a light emitting device. As an intermediate step between the preparing step and the phosphor layer forming step,
A diffuse reflection portion forming step of forming a diffuse reflection portion for suppressing total reflection on a part of a light emitting surface on the translucent crystal substrate corresponding to the light emitting element for emitting light from the light emitting layer to the outside; The method for manufacturing a light emitting device according to claim 1, wherein:   6. The method according to claim 1, wherein the phosphor layer forming step includes a polishing step of polishing an upper surface of the phosphor layer. As an intermediate step between the preparing step and the phosphor layer forming step, the boundary between the plurality of light emitting elements on the blue LED wafer is ground to form a groove, thereby improving the luminous efficiency. The method further includes a groove grinding step for forming a side surface of the light emitting element,
The method according to claim 1, wherein, in the phosphor layer forming step, the phosphor layer is formed also in the groove.   As a step after the phosphor layer forming step, the method further comprises an inspection step of inspecting the chromaticity of light emitted from the upper surface of the phosphor layer after each of the plurality of light emitting elements emits light. The method for manufacturing a light-emitting device according to claim 1, wherein:   9. The method according to claim 1, wherein the preparing step, the phosphor layer forming step, and the cutting step are performed in this order.   9. The method according to claim 1, wherein the cutting step is performed before the phosphor layer forming step. Instead of the cutting step,
The method according to claim 10, further comprising a bending step of cutting a boundary between the plurality of light emitting elements on the blue LED wafer by cutting. A method for manufacturing a light-emitting element for manufacturing a light-emitting element that emits ultraviolet light from a light-emitting layer formed by stacking a semiconductor film on a light-transmitting crystal substrate to the outside through a phosphor layer, ,
A preparing step of preparing an ultraviolet LED wafer in which the light emitting layers corresponding to a plurality of the light emitting elements are formed on the translucent crystal substrate;
Any one of three primary colors of R (red), G (green) and B (blue) for converting the ultraviolet light into white light is provided on the upper surface of the ultraviolet LED wafer on the side opposite to the light emitting layer. An individual phosphor layer forming step of applying and curing the phosphor of the above, and forming a phosphor layer of one layer of any one of the primary colors;
A cutting step of cutting boundaries between the plurality of light emitting elements on the ultraviolet LED wafer,
A method for manufacturing a light emitting device, comprising:   13. The method according to claim 12, wherein the individual phosphor layer forming step includes a removing step of removing excess phosphor cured on the upper surface of the ultraviolet LED wafer. As an intermediate step between the preparation step and the individual phosphor layer forming step, a boundary between the plurality of light emitting elements on the ultraviolet LED wafer is ground to form a groove, thereby improving luminous efficiency. The method further includes a groove grinding step of forming a side surface of the light emitting element,
14. The method according to claim 12, wherein the phosphor layer is formed also in the groove in the individual phosphor layer forming step.   15. The method according to claim 12, wherein the preparing step, the individual phosphor layer forming step, and the cutting step are performed in this order.   The method according to claim 12, wherein the cutting step is performed prior to the individual phosphor layer forming step. Instead of the cutting step,
17. The method according to claim 16, further comprising a bending step of cutting a boundary between the plurality of light emitting elements on the ultraviolet LED wafer by cutting. As an intermediate step between the preparing step and the individual phosphor layer forming step,
A diffuse reflection portion forming step of forming a diffuse reflection portion for suppressing total reflection on a part of a light emitting surface on the translucent crystal substrate corresponding to the light emitting element for emitting light from the light emitting layer to the outside; The method for manufacturing a light emitting device according to any one of claims 12 to 17, wherein:   19. The light emitting device according to claim 12, wherein the individual phosphor layer forming step is repeated for three layers of the three primary colors to form the three phosphor layers. Manufacturing method. The entire surface of the light-emitting surface through the translucent crystal substrate for emitting light from the light-emitting layer corresponding to the light-emitting element to the outside is set as a light-emitting region, and each of the light-emitting devices shares its own light to combine the white light by additive color mixing. A plurality of light-emission sharing regions that emit colors are pre-assigned in the light-emitting region,
In the individual phosphor layer forming step, a phosphor layer for emitting the assigned color is formed as a shared phosphor layer for a light emission sharing region in which one of the primary colors is assigned to the self. The method for manufacturing a light emitting device according to any one of claims 12 to 19, characterized in that:   21. The method for manufacturing a light emitting device according to claim 20, wherein the plurality of light emission sharing regions include a light emission sharing region for emitting three primary colors in which each of the three primary colors is assigned to itself. . As an intermediate step between the preparing step and the individual phosphor layer forming step,
22. The method according to claim 20, further comprising a sub-groove forming step of grinding and forming sub-grooves for sub-dividing the entire surface of the light-emitting surface in correspondence with the plurality of light-emission sharing regions. A method for manufacturing a light emitting device. Instead of forming the three phosphor layers,
20. The method according to claim 19, further comprising a mixed phosphor layer forming step of forming a phosphor layer of the mixed phosphor by applying and curing a mixed phosphor formed by mixing the phosphors of the three primary colors in advance. 3. The method for manufacturing a light emitting device according to item 1.   In the individual phosphor layer forming step, a phosphor layer for one of the primary colors is formed by performing vapor deposition instead of applying the phosphor of any one of the primary colors. A method for manufacturing a light-emitting device according to claim 12.   24. The light emission according to claim 23, wherein, in the mixed phosphor layer forming step, a phosphor layer of the mixed phosphor is formed by performing vapor deposition instead of applying the mixed phosphor. Device manufacturing method. It is manufactured according to the method for manufacturing a light emitting device according to any one of claims 1 to 25,
A light-emitting element, wherein light emitted from the light-emitting layer is emitted to the outside via the translucent crystal substrate and the phosphor layer. A light-emitting layer that is formed by stacking a gallium nitride-based compound semiconductor film on a translucent crystal substrate and emits blue light;
An electrode surface formed having a p-side electrode and an n-side electrode as a surface on the light emitting layer side of the translucent crystal substrate;
It is made of a phosphor material for emitting light of a wavelength having a complementary color with the blue light, and is formed by laminating in the outer peripheral edge of the translucent crystal substrate and on the top surface side opposite to the electrode surface. Phosphor layer,
With
A light-emitting device, wherein the blue light emitted from the light-emitting layer is emitted to the outside as white light by additive color mixture through the translucent crystal substrate and the phosphor layer. A light-emitting layer that is formed by stacking a gallium nitride-based compound semiconductor film on a translucent crystal substrate and emits ultraviolet light;
An electrode surface formed having a p-side electrode and an n-side electrode as a surface on the light emitting layer side of the translucent crystal substrate;
R (red), G (green) and B (blue) are formed in the outer peripheral edge of the translucent crystal substrate and on the side of the top surface opposite to the electrode surface for converting the ultraviolet light into white light. A) a phosphor layer comprising phosphor materials of the three primary colors;
With
A light-emitting device, wherein the ultraviolet light emitted from the light-emitting layer is emitted to the outside as white light through the translucent crystal substrate and the phosphor layer.   The light emitting device according to claim 28, wherein the phosphor layer is formed by laminating three phosphor layers of three primary colors each corresponding to each of the three primary colors. .   29. The light emitting device according to claim 28, wherein the phosphor layer is formed by laminating a mixed phosphor obtained by previously mixing the phosphor materials of the three primary colors. A light-emitting layer that is formed by stacking a gallium nitride-based compound semiconductor film on a translucent crystal substrate and emits blue light;
An electrode surface formed having a p-side electrode and an n-side electrode as a surface on the light emitting layer side of the translucent crystal substrate;
Of the entire body surface of the light-transmitting crystal substrate, a light-emitting surface that emits the blue light from the light-emitting layer to the outside only through the light-transmitting crystal substrate,
A phosphor layer laminated on part of the light emitting surface,
A light emitting device comprising:
In order to emit the blue light emitted from the light emitting layer to the outside as white light by addition and mixing through the translucent crystal substrate and the phosphor layer, the entire light emitting surface as a light emitting region, A plurality of light-emission sharing regions each emitting its own assigned color are provided in the light-emitting region,
The light emitting element according to claim 1, wherein the phosphor layer is formed by laminating a phosphor material for emitting each of the shared colors to each of the light emission sharing regions.   In the plurality of light-emission sharing regions, a light-emission sharing region for emitting the blue light as its own assigned color, and a light-emission sharing region for emitting complementary color light having a wavelength in a complementary color relationship with the blue light, The light emitting device according to claim 31, wherein is included. A light-emitting layer that is formed by stacking a gallium nitride-based compound semiconductor film on a translucent crystal substrate and emits ultraviolet light;
An electrode surface formed having a p-side electrode and an n-side electrode as a surface on the light emitting layer side of the translucent crystal substrate;
Of the entire body surface of the light-transmitting crystal substrate, a light-emitting surface that emits the ultraviolet light from the light-emitting layer to the outside only through the light-transmitting crystal substrate,
A phosphor layer laminated on part of the light emitting surface,
A light emitting device comprising:
In order to emit the ultraviolet light emitted from the light emitting layer to the outside as white light by adding and mixing color through the translucent crystal substrate and the phosphor layer, the entire light emitting surface as a light emitting region, A plurality of light-emission sharing regions each emitting its own assigned color are provided in the light-emitting region,
The light emitting element according to claim 1, wherein the phosphor layer is formed by laminating a phosphor material for emitting each of the shared colors to each of the light emission sharing regions.   In the plurality of light-emission sharing regions, light of one of three primary colors of R (red), G (green), and B (blue) or light obtained by adding and mixing two or more primary colors is used as its own assigned color. The light-emitting device according to claim 33, further comprising a light-emission sharing region for emitting light.   35. The light-emitting device according to claim 31, wherein subdivision grooves are provided to subdivide the entire surface of the light-emitting surface corresponding to the plurality of light-emission sharing regions.   36. A diffuse reflection portion for suppressing total reflection is provided on a part of a light-emitting surface of the translucent crystal substrate that emits light from the light-emitting layer to the outside. The light-emitting device according to item 1. The translucent crystal substrate is formed in such a manner that a top surface side opposite to the electrode surface is cut into a cross-sectional curve along an outer periphery thereof, and the phosphor layers are stacked so as to conform to the shape. The light emitting device according to any one of claims 27 to 36, wherein the light emitting device is provided.

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