JP2013161902A - Semiconductor light-emitting element manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor light-emitting element manufacturing method which can achieve simplification of a process of forming a concavo-convex shape.SOLUTION: A semiconductor light-emitting element manufacturing method comprises: performing a mixed layer formation process of forming on a p-type contact layer 80 by sputtering, a mixed layer PC11 in which a crystal part PC12 and a non-crystal part PC13 are mixed. Accordingly, the crystal part PC12 covers a part 81a of a surface 81 of the p-type contact layer 80. The non-crystal part PC13 covers a remaining part 81b of the surface 81 of the p-type contact layer 80 and a convex shape part PC12a of the crystal part PC12. The semiconductor light-emitting element manufacturing method comprises: subsequently performing a non-crystal part removal process of removing the non-crystal part PC13 from the mixed layer PC11 by oxalic acid etching. Accordingly, the remaining part 81b of the p-type contact layer 80 and the convex shape part PC12a of the crystal part PC12 are exposed. The semiconductor light-emitting element manufacturing method further comprises: forming a mixed layer PC14.

Description

  The present invention relates to a method for manufacturing a semiconductor light emitting device. More specifically, the present invention relates to a method for manufacturing a semiconductor light emitting element that forms an uneven light extraction surface.

  In a semiconductor light emitting device, a conductive transparent film is often formed on a semiconductor layer. This is because a current is passed through the semiconductor layer and light emitted from the light emitting layer is efficiently extracted to the outside. If the surface of the conductive transparent film is flat, most of the light is reflected by interface reflection. With this, light cannot be efficiently extracted outside the semiconductor light emitting device.

  Therefore, it is generally performed to form an uneven light extraction surface by roughening the surface of the conductive transparent film. For example, in Patent Document 1, the surface of a conductive transparent film is selectively irradiated with laser light, and a portion that has not been irradiated with laser light is selectively etched to pattern an uneven shape on the conductive transparent film. A technique is disclosed (see paragraph [0031] of Patent Document 1). Patent Document 2 discloses a technique for forming an uneven shape on a conductive transparent film by photolithography or laser scribing (see paragraph [0057] of Patent Document 2).

JP 2006-128227 A JP 2006-294907 A

  However, in order to use the methods described in Patent Document 1 and Patent Document 2, a laser irradiation process, a mask formation process, and the like are further required after the conductive transparent film is once formed. That is, another process for forming the uneven shape is necessary after the formation of the conductive transparent film. Therefore, there are many manufacturing processes. Also, the manufacturing cost of the product remained high.

  The present invention has been made to solve the above-described problems of the prior art. That is, an object of the present invention is to provide a method for manufacturing a semiconductor light-emitting element that simplifies the process of forming the concavo-convex shape.

  The method for manufacturing a semiconductor light emitting element according to the first aspect is a method having a concavo-convex shape forming step in which a light extraction surface for extracting light emitted from the light emitting layer is formed into a concavo-convex shape. In the concavo-convex shape forming step, the crystal portion having a plurality of convex portions covering a portion of the underlayer and the amorphous portion covering the remainder and the crystal portion of the underlayer are mixed in the underlayer by sputtering. A mixed layer forming step of forming the mixed layer, and an amorphous portion removing step of removing the non-crystalline portion from the mixed layer by etching to expose the remaining portion of the base layer and the convex portion of the crystalline portion.

  In such a method for manufacturing a semiconductor light emitting device, it is possible to form an uneven light extraction surface by utilizing the fact that the etching rate of the crystal part is extremely smaller than the etching rate of the non-crystalline part. And the convex part of a crystal | crystallization part is very small. Therefore, a fine uneven shape can be formed.

  In the method for manufacturing a semiconductor light emitting device according to the second aspect, the material of the mixed layer formed in the mixed layer forming step is a transparent conductive oxide. This is because light can be efficiently extracted from the electrode layer serving as the light extraction surface.

In the method for manufacturing a semiconductor light emitting device according to the third aspect, the conductive oxide is any one of ITO, ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ . In any case, the mixed layer can be formed by sputtering.

  In the method for manufacturing a semiconductor light emitting device according to the fourth aspect, the mixed layer forming step includes mixing a mixed gas obtained by mixing an inert gas with an oxygen gas in a range of 0.1% to 1.0% by volume. Sputtering is performed using the supplied gas. This is because a mixed layer in which the crystalline portion and the non-crystalline portion are mixed can be suitably formed.

  In the method for manufacturing a semiconductor light emitting device according to the fifth aspect, in the non-crystalline part removing step, wet etching is performed using an acidic solution. This is because by using this weakly acidic solution, it is possible to dissolve the non-crystal part and hardly dissolve the crystal part.

  In the method for manufacturing a semiconductor light emitting device according to the sixth aspect, oxalic acid is used as the acidic solution in the non-crystalline part removing step. This is because it is suitable for etching in the amorphous part removing step.

  In the method for manufacturing a semiconductor light emitting device according to the seventh aspect, the mixed layer forming step is a step of forming a mixed layer using the p-type contact layer as a base layer, and the non-crystalline part removing step is a remaining part of the p-type contact layer. And a step of exposing the crystal portion, and a step of forming a concavo-convex layer for forming a concavo-convex layer on the remaining portion of the p-type contact layer and the crystal portion. By using this method, an uneven light extraction surface can be suitably formed on the p-type contact layer side.

  In the method for manufacturing a semiconductor light emitting element according to the eighth aspect, the concavo-convex layer is an amorphous layer made of the same material as the mixed layer, and after the concavo-convex layer forming step, the crystal portion and the concavo-convex layer are 200 ° C. or higher and 800 ° C. or lower. It has a heating step of heating at a temperature within the range to make the crystal part and the concavo-convex layer as an integral crystal layer. By using this method, an uneven shape can be formed in the integral crystal layer.

In the method for manufacturing a semiconductor light emitting element according to the ninth aspect, the concavo-convex layer is any one of ITO, ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ and is made of a material different from the mixed layer. It is. By using this method, a two-layer conductive transparent film is formed. The light extraction efficiency is improved by changing the refractive index.

  In the semiconductor light emitting device manufacturing method according to the tenth aspect, the concavo-convex shape forming step includes a crystal layer forming step of forming a crystal layer on the p-type contact layer before the mixed layer forming step. In the mixed layer forming step, a mixed layer made of the same material as the base layer is formed using the crystal layer as the base layer. It is easy to form a crystal layer with a suitable thickness.

  In the method for manufacturing a semiconductor light emitting device according to the eleventh aspect, the crystal layer forming step includes an amorphous layer forming step of forming an amorphous non-crystalline layer on the p-type contact layer, and the non-crystalline layer at 200 ° C. And a heating step of heating at a temperature in the range of 800 ° C. or lower to form a crystal layer. By using this method, a suitable crystal layer can be produced.

  In the method for manufacturing a semiconductor light emitting element according to the twelfth aspect, the crystal layer forming step is a step of forming the crystal layer on the p-type contact layer at a temperature in the range of 100 ° C. to 400 ° C. Thereby, a crystal layer can be formed with few processes.

  In the method for manufacturing a semiconductor light emitting device according to the thirteenth aspect, the uneven shape forming step includes a non-crystalline layer forming step of forming an amorphous non-crystalline layer as a base layer, and a mixed layer of the same material as the non-crystalline layer. A mixed layer forming step to be formed; a non-crystalline portion removing step for removing a part of the non-crystalline layer and a non-crystalline portion; a heating step for heating the rest of the non-crystalline layer and the crystalline portion to form an integral crystalline layer; Have An uneven shape with large unevenness can be formed.

  In the method for manufacturing a semiconductor light emitting device according to the fourteenth aspect, the concavo-convex shape forming step includes a mixed layer forming step of forming a mixed layer using the group III nitride semiconductor layer as a base layer, and removing an amorphous portion from the mixed layer. A non-crystalline portion removing step for exposing the remaining portion of the group III nitride semiconductor layer and the crystal portion, and a semiconductor etching step for dissolving the remaining portion of the exposed group III nitride semiconductor layer by etching to form a recess, And an uneven layer forming step of forming an uneven layer in the crystal part and the recess. By using this method, a recess can be formed in the group III nitride semiconductor layer, and an uneven light extraction surface can be formed.

  In the method for manufacturing a semiconductor light emitting device according to the fifteenth aspect, in the step of forming the concavo-convex shape, the crystal portion and the concavo-convex layer are heated at a temperature in the range of 200 ° C. to 800 ° C. It has the heating process which makes it a layer. Thereby, only one crystal layer having an uneven shape can be formed on the uneven group III nitride semiconductor layer.

  In the method for manufacturing a semiconductor light emitting device according to the sixteenth aspect, in the mixed layer forming step, a mixed layer is formed using the sapphire substrate as a base layer, and in the amorphous portion removing step, the amorphous portion is removed to remove the sapphire substrate. The remainder and crystal parts are exposed. Thereby, an uneven crystal layer can be formed on the sapphire substrate.

  In the semiconductor light emitting device manufacturing method according to the seventeenth aspect, the concavo-convex shape forming step has a sapphire etching step in which the exposed portion of the exposed sapphire substrate is recessed by etching after the amorphous portion removing step. This is because an uneven shape is formed over the sapphire and the crystal portion.

  In the method for manufacturing a semiconductor light emitting element according to the eighteenth aspect, the uneven shape forming step includes a patterning step of performing patterning after the formation of the uneven shape. Thereby, more detailed patterning can be performed.

  In the method for manufacturing a semiconductor light emitting device according to the nineteenth aspect, in the mixed layer forming step, the thickness of the mixed layer to be formed is in the range of 1000 to 5000 and the film forming pressure is 0.1 to 0.4 Pa. Within the range, the sputtering rate is in the range of 2 Å / sec to 10 Å / sec. This is because a mixed layer in which the crystalline portion and the non-crystalline portion are mixed can be suitably formed.

  According to the present invention, there is provided a method for manufacturing a semiconductor light-emitting element that simplifies the process of forming a concavo-convex shape.

It is a schematic block diagram for demonstrating the laminated structure of the light emitting element which concerns on Example 1-4. FIG. 6 is a conceptual diagram (No. 1) for describing a method for manufacturing a light emitting element according to Example 1; FIG. 6 is a conceptual diagram (No. 2) for explaining the method for manufacturing the light-emitting element according to Example 1; FIG. 3 is a conceptual diagram (No. 3) for explaining the method for manufacturing the light-emitting element according to Example 1. FIG. 4 is a conceptual diagram (part 4) for explaining the method for manufacturing the light-emitting element according to Example 1; FIG. 6 is a conceptual diagram (No. 1) for describing a method for manufacturing a light-emitting element according to Example 2. FIG. 6 is a conceptual diagram (No. 2) for describing a method for manufacturing a light-emitting element according to Example 2. FIG. 6 is a conceptual diagram (No. 3) for explaining the method for manufacturing the light emitting element according to the second embodiment. FIG. 10 is a conceptual diagram (part 4) for explaining the method for manufacturing the light-emitting element according to Example 2; FIG. 6 is a conceptual diagram (No. 1) for describing a method for manufacturing a light-emitting element according to Example 3. FIG. 6 is a conceptual diagram (No. 2) for describing a method for manufacturing a light-emitting element according to Example 3. FIG. 6 is a conceptual diagram (No. 3) for explaining a method for manufacturing a light-emitting element according to Example 3. FIG. 10 is a conceptual diagram (part 4) for explaining the method for manufacturing the light-emitting element according to Example 3; FIG. 6 is a conceptual diagram (No. 1) for explaining a method for manufacturing a light-emitting element according to Example 4; It is a conceptual diagram (the 2) for demonstrating the manufacturing method of the light emitting element which concerns on Example 4. FIG. FIG. 6 is a conceptual diagram (No. 3) for describing a method for manufacturing a light emitting element according to Example 4; FIG. 10 is a conceptual diagram (part 4) for explaining a method for manufacturing a light-emitting element according to Example 4; FIG. 10 is a conceptual diagram (No. 5) for explaining the method for manufacturing the light emitting element according to the fourth embodiment. 6 is a schematic configuration diagram for explaining a stacked structure of a light emitting device according to Example 5. FIG. FIG. 6 is a conceptual diagram (No. 1) for describing a method for manufacturing a light-emitting element according to Example 5. FIG. 12 is a conceptual diagram (No. 2) for describing a method for manufacturing a light emitting element according to Example 5; FIG. 10 is a conceptual diagram (No. 3) for explaining a method for manufacturing a light-emitting element according to Example 5.

  Hereinafter, specific examples will be described with reference to the drawings by taking light emitting elements as examples. However, it is not limited to these examples. In addition, a laminated structure and an electrode structure of each layer of the light emitting element described later are examples. Of course, it may be a laminated structure different from the embodiment. And the thickness of each layer in each figure is shown conceptually and does not indicate the actual thickness. In addition, the uneven shape in each figure is drawn large for easy understanding. However, in practice, these uneven shapes are very fine shapes.

1. Semiconductor Light Emitting Element A light emitting element 100 manufactured by the method for manufacturing a semiconductor light emitting element according to this example will be described with reference to FIG. The light emitting element 100 is a face-up type semiconductor light emitting element. The light emitting element 100 has a plurality of semiconductor layers made of a group III nitride semiconductor.

  As shown in FIG. 1, the light emitting device 100 includes a sapphire substrate 10, a low-temperature buffer layer 20, an n-type contact layer 30, an n-type ESD layer 40, an n-type SL layer 50, and an MQW layer that is a light source. (Multiple quantum well layer) 60, p-type cladding layer 70, and p-type contact layer 80. Further, the n-type contact layer 30 is formed with an n-electrode N1. A p-electrode P <b> 1 is formed on the p-type contact layer 80.

  The sapphire substrate 10 is for forming each of the above layers on one surface thereof by MOCVD. And in order to improve light extraction efficiency, it is good for the surface to be uneven | corrugated. In addition to sapphire, SiC, ZnO, Si, GaN, or the like may be used as the growth substrate. The low temperature buffer layer 20 is for forming an upper layer while inheriting the crystallinity of the sapphire substrate 10. The material of the low temperature buffer layer 20 is, for example, AlN or GaN.

The n-type contact layer 30 is a layer that actually contacts the n-electrode N1. The n-type contact layer 30 is a layer made of n-GaN. The Si concentration is 1 × 10 ¹⁸ / cm ³ or more. The n-type contact layer 30 may be a plurality of layers having different carrier concentrations. This is to improve the ohmic property with the n-electrode.

The n-type ESD layer 40 is an electrostatic withstand voltage layer for preventing electrostatic breakdown of each semiconductor layer. The structure of the n-type ESD layer 40 is a laminated structure of non-doped GaN and Si-doped n-GaN. The doping amount of Si is preferably such that the carrier concentration is 1 × 10 ¹⁸ / cm ³ or more.

  The n-type SL layer 50 is a strain relaxation layer for relaxing stress applied to the MQW layer 60. More specifically, the n-type SL layer 50 is an n-type superlattice layer having a superlattice structure. As will be described later, the n-type SL layer 50 is obtained by repeatedly laminating a unit laminated body in which InGaN, GaN, and n-GaN are laminated. As shown in FIG. 1, the n-type SL layer 50 is located between the n-type ESD layer 40 and the MQW layer 60. The n-type ESD layer 40 and the MQW layer 60 are in contact with each other.

  The MQW layer 60 is a light emitting layer that emits light when electrons and holes are recombined. Therefore, the MQW layer 60 has a multiple quantum well structure in which well layers having a small band gap and barrier layers having a large band gap are alternately formed. Here, InGaN can be used as the well layer and AlGaN can be used as the barrier layer. Thus, the well layer contains In. Further, AlInGaN may be used as the barrier layer. Or these may be combined freely and it is good also as repeating the unit structure by making four or more layers into a unit structure.

  The p-type cladding layer 70 is for preventing electrons from diffusing into the p-type contact layer 80. The p-type cladding layer 70 is a layer formed by repeating a unit structure of a layer made of p-InGaN and a layer made of p-AlGaN as a unit structure. The number of repetitions is seven. Moreover, it is good also considering the repetition frequency as the range of 3-50 times.

  The p-type contact layer 80 is a layer that is actually in contact with the p-electrode P1. The p-type contact layer 80 is a layer made of p-GaN doped with Mg. In addition, any one of InGaN, AlGaN, and AlInGaN may be used as the material of the p-type contact layer 80. The p-type contact layer 80 appears on the surface of the light emitting element 100 opposite to the sapphire substrate 10.

Here, the thickness of the p-type contact layer 80 is in the range of 100 to 1000 mm. The Mg doping amount in the p-type contact layer 80 is in the range of 1 × 10 ¹⁹ / cm ^{3 to} 1 × 10 ²² / cm ³ . It should be noted that a plurality of layers may be formed so that the closer to the p-electrode P <b> 1 in the p-type contact layer 80, the larger the Mg doping amount.

  The p electrode P <b> 1 is a conductive transparent film that covers the p-type contact layer 80. The surface of the p electrode P1 is a light extraction surface. Therefore, an uneven shape is formed on the surface of the p electrode P1. This is for efficiently extracting light emitted from the MQW layer 60 which is a light emitting layer. The material of the p electrode P1 is ITO. A pad electrode may be formed on the p electrode P1.

2. Method for Manufacturing Semiconductor Light Emitting Element The method for manufacturing a semiconductor element according to the present embodiment is characterized by a concavo-convex shape forming step for forming a p-electrode P1 having a concavo-convex shape. Here, a method for manufacturing a semiconductor light emitting device will be described.

2-1. Semiconductor Layer Formation Step Crystals of each semiconductor layer were epitaxially grown by metal organic vapor phase epitaxy (MOCVD). First, the sapphire substrate 10 is placed inside the MOCVD furnace. On the sapphire substrate 10, the low-temperature buffer layer 20, the n-type contact layer 30, the n-type ESD layer 40, the n-type SL layer 50, the MQW layer 60, the p-type cladding layer 70, and the p-type contact layer 80 Are formed in this order. Thereby, the laminated body 90 in which each semiconductor layer was formed in the sapphire substrate 10 is formed. And the laminated body 90 is taken out from a MOCVD furnace. Note that a plurality of processes are performed on the laminate 90. Each time, what is formed in the laminate 90 changes. However, for convenience of explanation, it will be referred to as a laminate 90.

2-2. Uneven shape forming step Next, an uneven shape forming step is performed. In the concavo-convex shape forming step, the p-type contact layer 80 is used as a base layer, and the p-electrode P1 is formed thereon. Thereby, the laminated body 90 in which the p electrode P1 is formed is formed. This uneven shape forming step will be described in detail later.

2-3. n-electrode formation process Next, the n-electrode N1 is formed in the laminated body 90 in which the p-electrode P1 was formed. For this purpose, the n-type contact layer 30 is exposed to the light extraction surface side by covering a part of the laminate 90 with a laser or the like. Then, an n-electrode N1 is formed on the exposed n-type contact layer 30. As the n-electrode N1, a W layer, a Ti layer, and an Au layer were formed in this order from the n-type contact layer 30 side. In addition, you may interchange the order which this n electrode formation process and uneven | corrugated shape formation process perform. Thus, the light emitting element 100 was obtained.

3. Uneven shape forming process This embodiment is characterized by an uneven shape forming process of forming the p-electrode P1 on the surface of the laminate 90 shown in FIG. Therefore, an uneven | corrugated shape formation process is demonstrated here. The step of forming the conductive layer includes a mixed layer forming step, an amorphous part removing step, an uneven layer forming step, a heating step, and a patterning step. Hereinafter, it demonstrates in order.

3-1. Next, a mixed layer is formed on the stacked body 90. For this purpose, the laminate 90 is placed in a sputtering vacuum chamber. Then, the mixed layer PC11 is formed on the p-type contact layer 80 by sputtering, as shown in FIG. The p-type contact layer 80 is a base layer for forming the mixed layer PC11 by sputtering.

  Here, the mixed layer is a layer in which a crystalline portion and an amorphous portion are mixed. The crystal portion in the mixed layer grows using the seed crystal of the underlayer as a nucleus. Therefore, the crystal portion has a plurality of convex portions with the base layer as the bottom surface. The crystal portion covers a part of the surface of the underlayer. On the other hand, the non-crystalline part covers the convex part of the crystal part and covers the surface of the base layer that is not covered by the crystal part, that is, the remaining part of the surface of the base layer.

  As shown in FIG. 2, the mixed layer PC11 is a layer in which the crystal portion PC12 and the non-crystal portion PC13 are mixed. The crystal portion PC12 covers a part 81a of the surface 81 of the p-type contact layer 80. And it has the convex-shaped part PC12a which uses the part 81a of the surface 81 of the p-type contact layer 80 as a bottom face. The crystal portion PC12 grows using the seed crystal on the p-type contact layer 80 as a nucleus. Therefore, the degree of growth of the crystal part PC12 varies. In FIG. 2, the crystal parts PC12 have the same height, but actually, the crystal parts PC12 have various heights and widths.

  On the other hand, the amorphous portion PC13 is an amorphous portion. The part excluding the crystal part PC12 in the mixed layer PC11 is an amorphous part PC13. Therefore, the amorphous part PC13 is located on the surface side in the mixed layer PC11. As shown in FIG. 2, the amorphous portion PC13 covers the remaining portion 81b of the surface 81 of the p-type contact layer 80 and the convex portion PC12a of the crystalline portion PC12.

  In this embodiment, the entire surface 81 of the p-type contact layer 80 is not covered with the crystal portion PC12. This is because, in a later step, the non-crystalline portion PC13 is removed to expose a portion 81a of the surface 81 of the p-type contact layer 80 and the crystalline portion PC12.

  The mixed layer PC11 of FIG. 2 was formed by sputtering. The material of the mixed layer PC11 is ITO. Therefore, the crystal part PC12 is made of an ITO crystal. The amorphous part PC13 is made of an amorphous ITO. The sputtering conditions in this example were as follows.

[Table 1]
Oxygen 1.0%
Thickness 1000 Å
Deposition pressure 0.4 Pa
Deposition rate 3 Å / sec

  As shown in Table 1, the supply gas supplied at the time of sputtering is a mixed gas in which oxygen is mixed with Ar, which is an inert gas. The mixing ratio of oxygen in the supply gas was 1.0% by volume.

  By using the conditions shown in Table 1, a mixed layer in which the crystalline portion PC11 and the non-crystalline portion PC12 are mixed can be formed. However, instead of this, the sputtering conditions may be changed within the range of Table 2.

[Table 2]
Oxygen 0.1-1.0%
Thickness 1000-5000Å
Deposition pressure 0.1-0.4 Pa
Deposition rate 2-10 Å / sec

  That is, the mixing ratio of oxygen may be in the range of 0.1% to 1.0% by volume. The mixing ratio of oxygen is preferably in a range of 0.5% to 1.0% by volume. Moreover, the film thickness of mixed layer PC11 should just be 1000 to 5000 inches. The film forming pressure may be 0.1 Pa or more and 0.4 Pa or less. The film formation rate, that is, the sputtering rate may be 2 Å / sec or more and 10 Å / sec or less.

  And the laminated body 90 after forming mixed layer PC11 is taken out from the vacuum chamber for sputtering.

3-2. Noncrystalline Part Removal Step Subsequently, the amorphous part PC13 is removed from the mixed layer PC11 of FIG. Here, oxalic acid etching is performed. Therefore, the laminated body 90 is immersed in an oxalic acid tank. Here, the crystal portion PC12 is hardly dissolved in oxalic acid. On the other hand, the amorphous portion PC13 is easily dissolved in oxalic acid. This is because even if the same material is used, the bonding force between atoms is large in the crystalline portion PC12 and small in the non-crystalline portion PC13.

  As a result, the amorphous portion PC13 covering the surface 81 of the p-type contact layer 80 and the crystal portion PC12 is removed from the mixed layer PC11. As a result, as shown in FIG. 3, the remaining portion 81b of the surface 81 of the p-type contact layer 80 and the convex portion PC12a of the crystal portion PC12 are exposed. However, in practice, the surface of the crystal portion PC12 is slightly dissolved.

3-3. Next, the laminate 90 from which the non-crystalline portion PC13 has been removed is placed in the sputtering vacuum chamber again. Then, sputtering is performed again in a state where the crystal portion PC12 is formed on the p-type contact layer 80 as shown in FIG.

  Thereby, as shown in FIG. 4, the mixed layer PC14 is formed. By this sputtering, the crystal part PC12 grows slightly. Then, an amorphous part PC15 covering the crystalline part PC12 is formed. The amorphous portion PC15 covers the convex shape of the crystalline portion PC12 and the remaining portion 81b of the surface 81 of the p-type contact layer 80. And the uneven | corrugated shape corresponding to the convex shape of crystal | crystallization part PC12 is formed in the surface of non-crystal part PC15. That is, the non-crystalline portion PC15 is an uneven layer having an uneven shape. The material of the non-crystalline portion PC15 is the same material as that of the crystalline portion PC12.

  The sputtering conditions here are the same as those shown in Table 1. Of course, you may carry out on conditions other than this. The material of the mixed layer PC14 formed by sputtering is the same as the material of the crystal part PC12. That is, ITO. And the laminated body 90 after mixed layer PC14 formation is taken out from the vacuum chamber for sputtering.

3-4. Heating process Next, the laminated body 90 after the formation of the mixed layer PC14 is put into the heating furnace. And the laminated body 90 is heated. The furnace temperature at that time is 700 degreeC. The furnace temperature may be in the range of 200 ° C. or higher and 800 ° C. or lower. Thereby, the mixed layer PC14 is crystallized. That is, the crystal part PC12 and the non-crystal part PC15 form an integrated crystal layer PC16 as shown in FIG. The crystal layer PC16 is crystallized ITO in which the concavo-convex shape Z10 is formed. And the laminated body 90 in which crystal layer PC16 was formed is taken out from a heating furnace.

3-5. Patterning Step Then, after forming the concavo-convex shape, various types of patterning are performed on the stacked body 90 after the crystal layer PC16 is formed. For this purpose, iron chloride etching is performed. With the above, a laminate 90 in which the p electrode P1 was formed was obtained.

  As described above in detail, in the method for manufacturing the light emitting element 100 of this example, a process for forming the uneven shape after the formation of the p electrode P1 is not required. Therefore, there are few processes. And the manufacturing cost is also low. Further, the light emitting element 100 can be manufactured without a laser scanning device.

4). Manufactured Light-Emitting Element A light-emitting element 100 manufactured by the method for manufacturing a semiconductor light-emitting element of this example has a p-electrode P1 having a concavo-convex shape Z10 as shown in FIG. The height of the convex shape of the p-electrode P1 is not necessarily uniform. Also, there are no laser scan marks or mask marks left. However, when a resist mask process described later is performed, the flat portion remains as a mask mark. Still, there is no trace of the mask in the region other than the region where the p-pad electrode is formed.

5. Modified example 5-1. Sputtering conditions In this example, the sputtering conditions performed in the concavo-convex layer forming step were the conditions under which a mixed layer in which a crystalline portion and an amorphous portion were mixed was formed. That is, the conditions shown in Table 1 and Table 2 were used. However, if an uneven layer is formed in this step, it is not necessary to form a mixed layer. That is, an amorphous layer or a crystal layer may be formed. Therefore, sputtering conditions for forming an amorphous layer or sputtering conditions for forming a crystal layer may be used.

5-2. Conductive oxide In this example, ITO, which is a transparent conductive oxide, was used as the p-electrode P1. However, in addition to ITO, transparent conductive oxides such as ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ can be used. This is because these conductive oxides can still form a mixed layer in which a crystalline portion and an amorphous portion are mixed by using a mixed gas of an inert gas and an oxygen gas as a supply gas.

5-3.2 Conductive Transparent Film In this embodiment, the material of the mixed layer PC11 formed in the mixed layer forming step and the material of the non-crystalline portion PC15 formed in the uneven layer forming step are the same material. It was. However, different materials may be used for the crystal part PC12 and the non-crystal part PC15. In that case, a two-layer conductive transparent film having a shape as shown in FIG. 4 is formed. Then, as the material of these layers, two kinds may be selected from ITO, ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ .

5-4. Resist Mask Formation Step A resist mask formation step for forming a resist mask may be performed before the non-crystalline part removal step. By forming a resist mask, a flat portion can be formed on the p-electrode P1. For example, a flat portion may be formed as a location where the p-pad electrode is formed.

6). Summary As described in detail above, the method for manufacturing the light emitting device 100 of this example is characterized by the uneven shape forming step. This uneven | corrugated shape formation process has a mixed layer formation process and an amorphous part removal process. In the mixed layer forming step, a mixed layer in which the crystalline portion and the non-crystalline portion are mixed is formed. In the non-crystalline part removing step, the non-crystalline part is removed to partially expose the p-type contact layer. Then, by forming the mixed layer again, it is possible to form the p-electrode P1 having the uneven shape.

  Example 2 will be described. The configuration of the light-emitting element of this example is the same as that of the light-emitting element 100 of Example 1. The manufacturing method of the light emitting element 100 of the present example is different from the manufacturing method of the light emitting element 100 of Example 1 only in the uneven shape forming step. Therefore, only the different uneven | corrugated shape formation process is demonstrated.

1. Uneven shape forming step The uneven shape forming step of the present example includes an amorphous layer forming step, a heating step, a mixed layer forming step, an amorphous portion removing step, and a patterning step. Hereinafter, each of these steps will be described.

1-1. Amorphous Layer Formation Step First, the laminate 90 is placed inside a sputtering vacuum chamber. Then, an amorphous layer PC21 is formed on the p-type contact layer 80 of the stacked body 90 by sputtering as shown in FIG. The amorphous layer PC21 is a layer made of amorphous ITO. And the laminated body 90 in which the amorphous layer PC21 was formed is taken out from the sputtering vacuum chamber.

1-2. Heating process Next, the laminated body 90 in which the amorphous layer PC21 is formed is placed in a heating furnace. And the laminated body 90 is heated. Thereby, the amorphous layer PC21 is also heated. The furnace temperature is 700 ° C. Moreover, about the furnace temperature, you may change within the range of 200 degreeC or more and 800 degrees C or less. Thereby, the amorphous layer PC21 is crystallized. The amorphous layer PC21 becomes a crystalline layer PC22 as shown in FIG. That is, the crystal layer PC22 is formed on the p-type contact layer 80. And the laminated body 90 is taken out from a heating furnace. These amorphous layer forming step and heating step are crystal layer forming steps for forming the crystal layer PC22.

1-3. Next, the laminated body 90 on which the crystal layer PC22 is formed is again put into the sputtering vacuum chamber. Then, as shown in FIG. 8, a mixed layer PC23 is formed on the crystal layer PC22 by sputtering. Here, the base layer for forming the mixed layer PC23 is the crystal layer PC22. The material of the mixed layer PC23 is ITO which is the same as the material of the crystal layer PC22. The sputtering conditions at this time are the same as in Table 1. Or you may change within the range of Table 2. As a result, a crystal part PC24 and an amorphous part PC25 are formed on the crystal layer PC22.

  Here, the region covered by the crystalline portion and the non-crystalline portion is the same as that in the first embodiment. That is, the crystal portion PC24 covers a part 281a of the surface 281 of the crystal layer PC22 that is the base layer, and has a plurality of convex portions PC24a. On the other hand, the non-crystal part PC25 covers the convex part PC24a of the crystal part PC24 and the remaining part 281b of the surface 281 of the crystal layer PC22 that is not covered by the crystal part PC24. And the laminated body 90 in which mixed layer PC23 was formed is taken out from the vacuum chamber for sputtering.

1-4. Non-crystalline part removal process Next, the laminated body 90 in which the mixed layer PC23 is formed is put in an oxalic acid tank. By this oxalic acid etching, the amorphous portion PC25 is removed as in the case of the first embodiment. As described above, oxalic acid is weakly acidic. Therefore, the crystal part PC24 hardly melts. Therefore, as shown in FIG. 9, the remaining portion 282b of the surface 282 of the crystal layer PC26, which is the underlayer, and the convex portion PC27a of the crystal layer PC27 are exposed. The crystal layers PC26 and PC27 are crystallized ITO.

1-5. Patterning Step After the formation of the uneven shape, various types of patterning are performed on the stacked body 90 after the crystal layers PC26 and PC27 are formed. For this purpose, iron chloride etching is performed. With the above, a laminate 90 in which the p electrode P1 was formed was obtained.

  As described above in detail, in the method for manufacturing the light emitting element 100 of this example, a process for forming the uneven shape after the formation of the p electrode P1 is not required. Therefore, there are few processes. And the manufacturing cost is also low. Further, the light emitting element 100 can be manufactured without a laser scanning device.

2. Light-Emitting Element Manufactured The light-emitting element 100 manufactured by the method for manufacturing a semiconductor light-emitting element of this example has a p-electrode P1 having an uneven shape Z20 as shown in FIG. The height of the convex shape of the p-electrode P1 is not necessarily uniform. Also, there are no laser scan marks or mask marks left. However, when a resist mask process described later is performed, the flat portion remains as a mask mark. Still, there is no trace of the mask in the region other than the region where the p-pad electrode is formed.

  Further, as shown in FIG. 9, the concavo-convex shape Z20 of the p-electrode P1 is formed by a convex portion PC27a of the ITO crystal layer PC27 and a remaining portion 282b of the surface 281 of the ITO crystal layer PC26. The remaining part 282b is a flat part. That is, the concavo-convex shape Z20 of the p-electrode P1 according to the present embodiment includes a flat portion (remaining portion 282b) and a convex portion (convex shape portion 27a) that protrudes outward from the flat portion.

3. Modification 3-1. Conductive oxide In this example, ITO, which is a transparent conductive oxide, was used as the p-electrode P1. However, in addition to ITO, transparent conductive oxides such as ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ can be used. This is because these conductive oxides can still form a mixed layer in which a crystalline portion and an amorphous portion are mixed by using a mixed gas of an inert gas and an oxygen gas as a supply gas.

3-2.2 Conductive Transparent Film of Layer In this embodiment, the material of the amorphous layer PC21 formed in the amorphous layer forming step and the material of the mixed layer PC23 formed in the mixed layer forming step are the same material. It was supposed to be. However, different materials may be used for the amorphous layer PC21 and the mixed layer PC23. In that case, a two-layer conductive transparent film having a shape as shown in FIG. 9 is formed. Then, as the material of these layers, two kinds may be selected from ITO, ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ .

3-3. Resist Mask Formation Step A resist mask formation step for forming a resist mask may be performed before the non-crystalline part removal step. By forming a resist mask, a flat portion can be formed on the p-electrode P1. For example, a flat portion may be formed as a location where the p-pad electrode is formed.

3-4. Crystal Layer Formation Step In this example, the amorphous layer PC21 was formed by the amorphous layer formation step, and the amorphous layer PC21 was changed to the crystal layer PC22 by the heating step. However, instead of forming these steps, the crystalline layer PC22 may be formed directly without forming the amorphous layer PC21. For this purpose, for example, the temperature in the vacuum chamber is set to 100 ° C. or higher and 400 ° C. or lower, and the crystal layer PC22 may be formed under the conditions.

4). Summary As described in detail above, the method for manufacturing the light emitting device 100 of this example is characterized by the uneven shape forming step. This uneven | corrugated shape formation process has a mixed layer formation process and an amorphous part removal process. In the mixed layer forming step, a mixed layer in which the crystalline portion and the non-crystalline portion are mixed is formed. In the non-crystal part removing step, the non-crystal part is removed to partially expose the crystal layer of the base layer. Thereby, p electrode P1 in which uneven | corrugated shape was formed can be formed.

  Example 3 will be described. The configuration of the light-emitting element of this example is the same as that of the light-emitting element 100 of Example 1. The manufacturing method of the light emitting element 100 of the present example is different from the manufacturing method of the light emitting element 100 of Example 1 only in the uneven shape forming step. Therefore, only the different uneven | corrugated shape formation process is demonstrated.

1. Uneven shape forming process The uneven shape forming process of this example includes an amorphous layer forming process, a mixed layer forming process, an amorphous part removing process, a heating process, and a patterning process. Hereinafter, each of these steps will be described.

1-1. Amorphous Layer Formation Step First, the laminate 90 is placed inside a sputtering vacuum chamber. Then, as shown in FIG. 10, an amorphous layer PC31 is formed on the p-type contact layer 80 of the stacked body 90 by sputtering. Here, the non-crystalline layer PC31 is a layer for use as a base layer in a later mixed layer forming step. The amorphous layer PC31 is a layer made of amorphous ITO. This is done under normal sputtering conditions. This normal sputtering condition is of course known.

1-2. Next, as shown in FIG. 11, the mixed layer PC32 is formed on the stacked body 90 in which the amorphous layer PC31 is formed. The material of the mixed layer PC32 is the same ITO as the material of the amorphous layer PC31. The sputtering conditions at that time are the same as those shown in Table 1. Alternatively, it may be selected from the range shown in Table 2. Thus, the crystalline portion PC33 and the amorphous portion PC34 are formed on the amorphous layer PC31 as an underlayer.

  Here, the region covered by the crystalline portion and the non-crystalline portion is the same as that in the first embodiment. That is, the crystal portion PC33 covers a part 381a of the surface 381 of the non-crystalline layer PC31 that is the base layer, and has a plurality of convex-shaped portions PC33a. On the other hand, the non-crystalline portion PC34 covers the convex portion PC33a of the crystal portion PC33 and covers the remaining portion 381b of the surface 381 of the non-crystalline layer PC31 that is not covered by the crystal portion PC33. And the laminated body 90 in which mixed layer PC32 was formed is taken out from the vacuum chamber for sputtering.

1-3. Non-crystalline part removal process Next, the laminated body 90 in which the mixed layer PC32 is formed is put in an oxalic acid tank. By this oxalic acid etching, the amorphous portion PC34 is removed as in the case of the first embodiment. As described above, oxalic acid is weakly acidic. Therefore, the crystal part PC33 is hardly dissolved.

  The amorphous portion PC31 shown in FIG. 11 is also partially removed by this oxalic acid etching. The portion where the non-crystalline portion PC31 is dissolved is the remaining portion 381b of the surface 381 of the non-crystalline layer PC31 that is not covered with the crystalline portion PC33. Therefore, as shown in FIG. 12, an amorphous portion PC 35 and a crystalline portion PC 33 are formed on the p-type contact layer 80.

  A part of this non-crystal part PC35 remains covered with the crystal part PC33. The remaining part of the amorphous part PC35 is exposed. And the recessed part X31 is formed in the remainder of the exposed non-crystalline part PC35. At this time, a concavo-convex shape is formed over the non-crystal part PC35 and the crystal part PC33. Then, the convex portion PC33a of the crystal portion PC33 and the concave portion X31 of the non-crystal portion PC35 are exposed.

1-4. Next, the laminated body 90 in which the non-crystalline layer PC35 and the crystal portion PC33 are formed is put into a heating furnace. And the laminated body 90 is heated. Thereby, the amorphous layer PC53 and the crystal portion PC33 are also heated. The furnace temperature is 700 ° C. Moreover, about the furnace temperature, you may change within the range of 200 degreeC or more and 800 degrees C or less. Thereby, as shown in FIG. 13, the non-crystalline layer PC35 and the crystal portion PC33 become an integrated crystal layer PC36. Of course, the concavo-convex shape Z30 is formed on the surface of the crystal layer PC36. And the laminated body 90 in which the crystal layer PC36 was formed is taken out from a heating furnace.

1-5. Patterning Step After the formation of the concavo-convex shape, various types of patterning are performed on the stacked body 90 after the crystal layer PC36 is formed. For this purpose, iron chloride etching is performed. With the above, a laminate 90 in which the p electrode P1 was formed was obtained.

  As described above in detail, in the method for manufacturing the light emitting element 100 of this example, a process for forming the uneven shape after the formation of the p electrode P1 is not required. Therefore, there are few processes. And the manufacturing cost is also low. Further, the light emitting element 100 can be manufactured without a laser scanning device.

2. Light-Emitting Element Manufactured The light-emitting element 100 manufactured by the method for manufacturing a semiconductor light-emitting element of this example has a p-electrode P1 on which an uneven shape Z30 is formed, as shown in FIG. The height of the convex shape of the p-electrode P1 is not necessarily uniform. Also, there are no laser scan marks or mask marks left. However, when a resist mask process described later is performed, the flat portion remains as a mask mark. Still, there is no trace of the mask in the region other than the region where the p-pad electrode is formed. Moreover, since the recessed part X31 is formed deeply, the unevenness | corrugation of uneven | corrugated shape Z30 is large compared with another Example.

3. Modification 3-1. Conductive oxide In this example, ITO, which is a transparent conductive oxide, was used as the p-electrode P1. However, in addition to ITO, transparent conductive oxides such as ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ can be used. This is because these conductive oxides can still form a mixed layer in which a crystalline portion and an amorphous portion are mixed by using a mixed gas of an inert gas and an oxygen gas as a supply gas.

3-2.2 Conductive Transparent Film of Layer In this example, the material of the amorphous layer PC31 formed in the amorphous layer forming step and the material of the mixed layer PC32 formed in the mixed layer forming step are the same material. It was supposed to be. However, different materials may be used for the amorphous layer PC31 and the mixed layer PC32. In that case, a two-layer conductive transparent film having a shape as shown in FIG. 12 is formed. Then, as the material of these layers, two kinds may be selected from ITO, ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ .

3-3. Resist Mask Formation Step A resist mask formation step for forming a resist mask may be performed before the non-crystalline part removal step. By forming a resist mask, a flat portion can be formed on the p-electrode P1. For example, a flat portion may be formed as a location where the p-pad electrode is formed.

4). Summary As described in detail above, the method for manufacturing the light emitting device 100 of this example is characterized by the uneven shape forming step. This uneven | corrugated shape formation process has a mixed layer formation process and an amorphous part removal process. In the mixed layer forming step, a mixed layer in which the crystalline portion and the non-crystalline portion are mixed is formed. Then, in the non-crystal part removing step, the non-crystal part PC34 in the upper layer and a part of the non-crystal part PC31 in the base layer are removed while leaving the crystal part PC33. And by heating and crystallizing, the p electrode P1 in which the uneven | corrugated shape was formed can be formed.

  Example 4 will be described. The configuration of the light-emitting element of this example is the same as that of the light-emitting element 100 of Example 1. The manufacturing method of the light emitting element 100 of the present example is different from the manufacturing method of the light emitting element 100 of Example 1 only in the uneven shape forming step. Therefore, only the different uneven | corrugated shape formation process is demonstrated.

1. Concave and convex shape forming step The concave and convex shape forming step of the present example includes a mixed layer forming step, an amorphous part removing step, a semiconductor etching step, a concave and convex layer forming step, a heating step, and a patterning step. Hereinafter, each of these steps will be described.

1-1. First, the laminate 90 is placed in a sputtering vacuum chamber. Next, as shown in FIG. 14, the mixed layer PC41 is formed on the p-type contact layer 80 as a base layer by sputtering. The sputtering conditions at that time are the same as those in Table 1. Alternatively, conditions in the range of Table 2 may be used. As a result, a crystalline portion PC42 and an amorphous portion PC43 are formed on the p-type contact layer 80.

  Here, the region covered by the crystalline portion and the non-crystalline portion is the same as that in the first embodiment. That is, the crystal portion PC42 covers a part 481a of the surface 481 of the p-type contact layer 80 and has a plurality of convex portions PC42a. On the other hand, the non-crystal part PC43 covers the convex part PC42a of the crystal part PC42 and the remaining part 481b of the surface 481 of the p-type contact layer 80 that is not covered by the crystal part PC42. And the laminated body 90 in which mixed layer PC41 was formed is taken out from the vacuum chamber for sputtering.

1-2. Non-crystalline part removal process Next, the laminated body 90 in which the mixed layer PC41 is formed is put in an oxalic acid tank. By this oxalic acid etching, the amorphous portion PC43 is removed as in the case of the first embodiment. As described above, oxalic acid is weakly acidic. Therefore, the crystal part PC42 hardly dissolves. Therefore, a crystal portion PC 42 as shown in FIG. 15 remains on the p-type contact layer 80. Then, the remaining part 481b of the surface 481 of the p-type contact layer 80 and the convex part PC42a of the crystal layer PC42 are exposed.

1-3. Semiconductor Etching Step Next, the stacked body 90 in which the crystal portion PC42 remains is placed in an etching solution tank. The etchant tank contains, for example, TMAH (tetramethylammonium hydroxide). Alternatively, other known etchants may be used.

  Thereby, the exposed exposed part of the p-type contact layer 80 is partially dissolved. On the other hand, the crystal portion PC42 does not dissolve. Therefore, the portion covered with the crystal portion PC42 does not dissolve. That is, the crystal part PC42 serves as a mask, and the portion of the p-type contact layer 80 under the crystal part PC42 is not dissolved.

  As a result, a recess is formed in the p-type contact layer 80 as shown in FIG. Of course, the concave portion is not covered with the crystal portion PC42. As a result, a concavo-convex shape extending over the p-type contact layer 80 and the crystal portion PC42 is formed on the surface of the stacked body 90.

1-4. Step of forming uneven layer Next, the laminated body 90 having the formed uneven shape is put into the vacuum chamber for sputtering again. Then, the mixed layer PC44 is formed on the p-type contact layer 80 of the stacked body 90 by sputtering.

  Thereby, as shown in FIG. 17, the mixed layer PC14 is formed. By this sputtering, the crystal portion PC42 grows slightly. Then, an amorphous part PC45 covering the crystalline part PC42 is formed. The amorphous portion PC45 covers the convex shape of the crystalline portion PC42 and the concave portion of the p-type contact layer 80. And the uneven | corrugated shape corresponding to the convex shape of the crystal | crystallization part PC42 is formed in the surface of the non-crystal | crystallization part PC45. That is, the non-crystalline portion PC45 is a concavo-convex layer having a concavo-convex shape.

  The sputtering conditions here are the same as those shown in Table 1. Of course, you may carry out on conditions other than this. The material of the non-crystal part PC45 is the same as the material of the crystal part PC42. That is, ITO. And the laminated body 90 after mixed-layer PC44 formation is taken out from the vacuum chamber for sputtering.

1-5. Heating step Next, the laminate 90 on which the mixed layer PC44 is formed is placed in a heating furnace. And the laminated body 90 is heated. Thereby, the crystal part PC42 and the non-crystal part PC45 are also heated. The furnace temperature is 700 ° C. Moreover, about the furnace temperature, you may change within the range of 200 degreeC or more and 800 degrees C or less. Thereby, as shown in FIG. 18, the crystal part PC42 and the non-crystal part PC45 become an integral crystal layer PC46. Of course, an uneven shape Z40 is formed on the surface of the crystal layer PC46. And the laminated body 90 in which crystal layer PC46 was formed is taken out from a heating furnace.

1-6. Patterning Step Then, after forming the concavo-convex shape, various types of patterning are performed on the stacked body 90 after the crystal layer PC46 is formed. For this purpose, iron chloride etching is performed. With the above, a laminate 90 in which the p electrode P1 was formed was obtained.

  As described above in detail, in the method for manufacturing the light emitting element 100 of this example, a process for forming the uneven shape after the formation of the p electrode P1 is not required. Therefore, there are few processes. And the manufacturing cost is also low. Further, the light emitting element 100 can be manufactured without a laser scanning device.

2. Manufactured Light-Emitting Element The light-emitting element 100 manufactured by the method for manufacturing a semiconductor light-emitting element of this example has a p-electrode P1 in which an uneven shape Z40 is formed, as shown in FIG. The height of the convex shape of the p-electrode P1 is not necessarily uniform. Also, there are no laser scan marks or mask marks left. However, when a resist mask process described later is performed, the flat portion remains as a mask mark. Still, there is no trace of the mask in the region other than the region where the p-pad electrode is formed.

  Further, the p-electrode P1 of this example has a recess X41 as shown in FIG. The recess X41 is recessed when viewed from the p-type contact layer 80 side. A flat portion X42 is formed at a position farthest from the p-type contact layer 80 in the recess X41. The p-electrode P <b> 1 is formed with a convex portion X <b> 43 that protrudes toward the outside of the light emitting element 100. And the top part X43a of the convex part X43 is located above the flat part X42 in FIG. That is, when the perpendicular line LL is lowered from the top part X43a to the formation surface X44 of the p-type contact layer 80, the flat part X42 is located at a position that intersects the perpendicular line LL.

3. Modification 3-1. Sputtering conditions In this example, the sputtering conditions performed in the concavo-convex layer forming step were the conditions under which a mixed layer in which a crystalline portion and an amorphous portion were mixed was formed. That is, the conditions shown in Table 1 and Table 2 were used. However, if an uneven layer is formed in this step, it is not necessary to form a mixed layer. That is, an amorphous layer or a crystal layer may be formed. Therefore, sputtering conditions for forming an amorphous layer or sputtering conditions for forming a crystal layer may be used.

3-2. Conductive oxide In this example, ITO, which is a transparent conductive oxide, was used as the p-electrode P1. However, in addition to ITO, transparent conductive oxides such as ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ can be used. This is because these conductive oxides can still form a mixed layer in which a crystalline portion and an amorphous portion are mixed by using a mixed gas of an inert gas and an oxygen gas as a supply gas.

3-3.2 Conductive Transparent Film In this embodiment, the material of the mixed layer PC41 formed in the mixed layer forming step and the material of the non-crystalline portion PC45 formed in the uneven layer forming step are the same material. It was. However, different materials may be used for the crystal portion PC42 and the non-crystal portion PC45. In that case, a two-layer conductive transparent film having a shape as shown in FIG. 17 is formed. Then, as the material of these layers, two kinds may be selected from ITO, ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ .

3-4. Resist Mask Formation Step A resist mask formation step for forming a resist mask may be performed before the non-crystalline part removal step. By forming a resist mask, a flat portion can be formed on the p-electrode P1. For example, a flat portion may be formed as a location where the p-pad electrode is formed.

3-5. GaN substrate etching process In this embodiment, the p-type contact layer 80 is etched by a semiconductor etching process. However, when a GaN substrate is used as the growth substrate, a concavo-convex shape can be formed on the GaN substrate by the same process as in this example. Therefore, the present invention can also be applied to a flip chip using a GaN substrate.

4). Summary As described in detail above, the method for manufacturing the light emitting device 100 of this example is characterized by the uneven shape forming step. This uneven | corrugated shape formation process has a mixed layer formation process, an amorphous part removal process, and an uneven | corrugated layer formation process. In the mixed layer forming step, a mixed layer in which the crystalline portion and the non-crystalline portion are mixed is formed. In the non-crystalline portion removing step, the non-crystalline portion is removed to partially expose the p-type contact layer, and the exposed portion of the p-type contact layer is also etched to form a recess in the p-type contact layer. To do. In the concavo-convex layer forming step, the concavo-convex layer is formed by further sputtering the p-type contact layer and the crystal portion where the concavo-convex is formed. Thereby, p electrode P1 in which uneven | corrugated shape was formed can be formed.

  Example 5 will be described. The light emitting device according to this example is a flip chip type semiconductor light emitting device having a light extraction surface on the sapphire substrate side. In Example 1 to Example 4, an uneven shape was formed on the p-type contact layer 80 side. This embodiment is characterized in that an uneven shape is formed on the sapphire substrate side, as will be described later.

1. Semiconductor Light-Emitting Element FIG. 19 shows a light-emitting element 200 manufactured by the method for manufacturing a semiconductor light-emitting element according to this example. The light emitting element 200 has a layer made of a group III nitride semiconductor. As shown in FIG. 19, the light emitting device 200 includes a sapphire substrate 210, a low-temperature buffer layer 220, an n-type contact layer 230, an n-type ESD layer 240, an n-type SL layer 250, an MQW layer 260, p A mold cladding layer 270 and a p-type contact layer 280 are formed in this order. Further, the n-type contact layer 230 is formed with an n-electrode N2. A p-electrode P <b> 2 is formed on the p-type contact layer 80.

  An uneven crystal layer L is formed on the lower surface of the sapphire substrate 210 in FIG. 19, that is, the surface on which the semiconductor layer is not formed. The surface of the crystal layer L is an uneven light extraction surface.

  Therefore, the p electrode P2 has no light extraction surface. Therefore, the p-electrode P2 does not need to be a transparent film. However, in order to reflect light to the light extraction surface side, the p electrode P2 is made of a material that reflects light and is conductive. Examples of the material of the p electrode P2 include Ag and an Ag alloy.

2. 2. Manufacturing method of semiconductor light emitting device 2-1. Concave and convex shape forming step A crystal layer L is formed on one surface of the sapphire substrate 210 as described later. Of course, an uneven shape is formed on the surface of the crystal layer L.

2-2. Semiconductor Layer Formation Step Next, the sapphire substrate 210 on which the crystal layer L has been formed is placed in the MOCVD furnace. On the surface of the sapphire substrate 210 where the crystal layer L is not formed, a low-temperature buffer layer 220, an n-type contact layer 230, an n-type ESD layer 240, an n-type SL layer 250, an MQW layer 260, p A mold cladding layer 270 and a p-type contact layer 280 are formed in this order. Thereby, the laminated body 290 is formed.

2-3. Electrode Formation Step Next, the p-electrode P2 and the n-electrode N2 are formed on the stacked body 290. The n electrode N2 may be formed in the same manner as the method for forming the n electrode N1 in the first embodiment.

3. Uneven shape forming step The uneven shape forming step of the present example includes a mixed layer forming step and an amorphous portion removing step. Therefore, each step will be described below.

3-1. First, the sapphire substrate 210 is placed in the sputtering vacuum chamber. Then, as shown in FIG. 20, the mixed layer PC51 is formed thereon using the sapphire substrate 210 as a base layer. The sputtering conditions at that time are the same as those in Table 1. The conditions may be selected within the range shown in Table 2. Thereby, the crystal part PC52 and the non-crystal part PC53 are formed on the sapphire substrate 210.

  Here, the region covered by the crystalline portion and the non-crystalline portion is the same as that in the first embodiment. In other words, the crystal part PC52 covers a part 581a of the surface 581 of the sapphire substrate 210 as a base layer and has a plurality of convex-shaped parts PC52a. On the other hand, the non-crystal part PC53 covers the convex part PC52a of the crystal part PC52 and the remaining part 581b of the surface 581 of the sapphire substrate 210 that is not covered by the crystal part PC52. Then, the sapphire substrate 210 on which the mixed layer PC51 is formed is taken out from the sputtering vacuum chamber.

3-2. Next, the sapphire substrate 210 on which the mixed layer PC51 is formed is placed in an oxalic acid bath. By this oxalic acid etching, the amorphous portion PC53 is removed as in the case of the first embodiment. As described above, oxalic acid is weakly acidic. Therefore, the crystal part PC52 hardly dissolves. Therefore, as shown in FIG. 21, the convex portion PC52a of the crystal portion PC52 and the remaining portion 581b of the surface 581 of the sapphire substrate 210 are exposed.

  Thereby, the sapphire substrate 210 in which the uneven shape Z50 is formed is manufactured. The uneven shape Z50 is formed over the convex portion PC52a of the crystal portion PC52 and the remaining portion 581b of the sapphire substrate 20. The crystal portion PC52 is a crystal layer L.

  And the light emitting element 200 is manufactured by implementing a semiconductor layer formation process and an electrode formation process to the sapphire substrate 210 in which the crystal layer L was formed.

  As described in detail above, in the method for manufacturing the light-emitting element 200 of the present embodiment, it is possible to easily form an uneven shape on the sapphire substrate 210. In addition, the light emitting element 200 can be manufactured without a laser scanning device.

4). Manufactured Light-Emitting Element A light-emitting element 200 manufactured by the method for manufacturing a semiconductor light-emitting element of this example has a sapphire substrate 210 on which an uneven shape Z50 is formed, as shown in FIG. The height of the convex shape of the crystal layer L is not necessarily uniform. Also, there are no laser scan marks or mask marks left.

5. Modified example 5-1. Conductive oxide In this example, as the crystal layer L, ITO, which is a transparent conductive oxide, was used. However, in addition to ITO, transparent conductive oxides such as ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ can be used. This is because these conductive oxides can still form a mixed layer in which a crystalline portion and an amorphous portion are mixed by using a mixed gas of an inert gas and an oxygen gas as a supply gas.

5-2. In this example, the semiconductor layer forming step and the electrode forming step were performed after the concavo-convex shape forming step for forming the crystal layer L on the sapphire substrate 210 was performed. However, the order of these steps may be changed. The uneven shape forming step may be performed after the semiconductor layer forming step and before the electrode forming step. Moreover, it is good also as performing an uneven | corrugated shape formation process after an electrode formation process.

5-3. Sapphire Etching Step In this example, the crystal layer L was formed into an uneven shape. However, the exposed sapphire substrate 210 may be etched to form a recess in the exposed exposed portion of the sapphire substrate 210 as shown in FIG. That is, the sapphire etching process may be performed after the non-crystalline part removing process.

  In the sapphire etching process, the sapphire substrate 210 on which the crystal portion PC52 is formed is immersed in an etchant bath. In this etching solution tank, for example, a mixed solution of sulfuric acid and phosphoric acid is contained. Alternatively, a mixed solution of hydrochloric acid and phosphoric acid is contained. Alternatively, other known etchants may be used. Further, dry etching using Cl gas or the like may be performed. Here, sapphire is dissolved using the crystal portion PC52 as a mask.

  Therefore, as shown in FIG. 22, the recessed part X51 is formed in the exposed location in the sapphire substrate 210. FIG. Thereby, the uneven | corrugated shape Z60 covering the recessed part X51 of the sapphire substrate 210 and the convex-shaped part PC52a of the crystal | crystallization part PC52 is formed. The crystal part PC52 may be removed by a sapphire etching process.

6). Summary As described in detail above, the method for manufacturing the light-emitting element 200 of this example is characterized by the uneven shape forming step. This uneven | corrugated shape formation process has a mixed layer formation process and an amorphous part removal process. In the mixed layer forming step, a mixed layer in which the crystalline portion and the non-crystalline portion are mixed is formed. In the non-crystalline part removing step, the non-crystalline part is removed to partially expose the sapphire substrate 210. As a result, the light emitting element 200 having a concavo-convex shape formed on the sapphire substrate 210 can be formed.

  The first to fifth embodiments described above are merely examples. Therefore, naturally, various improvements and modifications can be made without departing from the scope of the invention. The laminated structure of the laminated body is not necessarily limited to that shown in the drawing. You may select arbitrarily, such as a laminated structure and the repetition frequency of each layer. Moreover, it is not restricted to a metal organic chemical vapor deposition method (MOCVD method). Any other method may be used as long as the crystal is grown using a carrier gas. Further, the semiconductor layer may be formed by other epitaxial growth methods such as a liquid phase epitaxy method and a molecular beam epitaxy method. Furthermore, it is not necessarily limited to a group III nitride semiconductor, and may be used when manufacturing other semiconductor light emitting devices.

DESCRIPTION OF SYMBOLS 10, 210 ... Sapphire substrate 20, 220 ... Low temperature buffer layer 30, 230 ... n-type contact layer 40, 240 ... n-type ESD layer 50, 250 ... n-type SL layer 60, 260 ... MQW layer 70, 270 ... p-type cladding Layers 80, 280 ... p-type contact layers 90, 290 ... Laminated body 100, 200 ... Light emitting elements 81, 281,282, 381,481,581 ... Surfaces 81a, 281a, 282a, 381a, 481a, 581a ... Part 81b, 281b, 282b, 381b, 481b, 581b ... balance N1, N2 ... n electrode P1, P2 ... p electrode PC11, PC14, PC23, PC32, PC41, PC44, PC51 ... mixed layer PC12, PC24, PC33, PC42, PC52 ... crystal Partial PC13, PC15, PC25, PC34, PC43, PC45, P 53: Amorphous portions PC16, PC22, PC26, PC27, PC36, PC46, L ... Crystal layers PC21, PC31, PC35 ... Amorphous layers PC12a, PC27a, PC33a, PC42a, PC52a ... Convex-shaped portions Z10, Z20, Z30, Z40 , Z50, Z60 ... uneven shape

Claims (19)

In the method for manufacturing a semiconductor light emitting device having a concavo-convex shape forming step in which the light extraction surface for extracting light emitted from the light emitting layer is concavo-convex
The uneven shape forming step includes:
A mixed layer in which a crystal part having a plurality of convex portions covering a part of the base layer and an amorphous part covering the rest of the base layer and the crystal part are mixed with the base layer by sputtering. A mixed layer forming step to be formed;
Removing the non-crystalline part from the mixed layer by etching to expose the remaining part of the underlayer and the convex part of the crystalline part; and
A method for manufacturing a semiconductor light emitting device, comprising: In the manufacturing method of the semiconductor light-emitting device according to claim 1,
The material of the mixed layer formed in the mixed layer forming step is
A method for producing a semiconductor light emitting device, which is a transparent conductive oxide. In the manufacturing method of the semiconductor light-emitting device according to claim 2,
The conductive oxide is
A method of manufacturing a semiconductor light emitting device, wherein the semiconductor light emitting device is any one of ITO, ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ . In the manufacturing method of the semiconductor light-emitting device according to any one of claims 1 to 3,
The mixed layer forming step includes
A method for manufacturing a semiconductor light emitting device, wherein sputtering is performed using a mixed gas obtained by mixing an inert gas and an oxygen gas in a range of 0.1% to 1.0% by volume as a supply gas. In the manufacturing method of the semiconductor light-emitting device according to any one of claims 1 to 4,
In the non-crystal part removing step,
A method for manufacturing a semiconductor light emitting device, wherein wet etching is performed using an acidic solution. In the manufacturing method of the semiconductor light-emitting device according to claim 5,
In the non-crystal part removing step,
Oxalic acid is used as said acidic solution, The manufacturing method of the semiconductor light-emitting device characterized by the above-mentioned. In the manufacturing method of the semiconductor light-emitting device according to any one of claims 1 to 6,
The mixed layer forming step includes
a step of forming a mixed layer using a p-type contact layer as a base layer,
The non-crystal part removing step includes
Exposing the remainder of the p-type contact layer and the crystal portion;
A method for manufacturing a semiconductor light emitting device, comprising: forming a concavo-convex layer on the remaining portion of the p-type contact layer and the crystal portion. In the manufacturing method of the semiconductor light-emitting device according to claim 7,
The uneven layer is
An amorphous layer of the same material as the mixed layer,
After the uneven layer forming step,
Heating the crystal portion and the concavo-convex layer at a temperature within a range of 200 ° C. or higher and 800 ° C. or lower to form the crystal portion and the concavo-convex layer as an integral crystal layer,
A method for manufacturing a semiconductor light emitting device. In the manufacturing method of the semiconductor light-emitting device according to claim 7,
The uneven layer is
A method of manufacturing a semiconductor light emitting device, characterized in that it is a layer made of a material different from the mixed layer, which is any one of ITO, ICO, IZO, ZnO, TiO ₂ , NbTiO ₂ , and TaTiO ₂ . In the manufacturing method of the semiconductor light-emitting device according to any one of claims 1 to 6,
The uneven shape forming step includes:
A crystal layer forming step of forming a crystal layer on the p-type contact layer before the mixed layer forming step;
In the mixed layer forming step,
A method of manufacturing a semiconductor light emitting element, wherein a mixed layer of the same material as that of the base layer is formed using the crystal layer as the base layer. In the manufacturing method of the semiconductor light emitting element according to claim 10,
The crystal layer forming step includes
A non-crystalline layer forming step of forming an amorphous non-crystalline layer on the p-type contact layer;
Heating the amorphous layer at a temperature in the range of 200 ° C. or higher and 800 ° C. or lower to form a crystalline layer;
A method for manufacturing a semiconductor light emitting device, comprising: In the manufacturing method of the semiconductor light emitting element according to claim 10,
The crystal layer forming step includes
A method of manufacturing a semiconductor light emitting device, comprising forming a crystal layer on the p-type contact layer at a temperature in the range of 100 ° C. to 400 ° C. In the manufacturing method of the semiconductor light-emitting device according to any one of claims 1 to 6,
The uneven shape forming step includes:
An amorphous layer forming step of forming an amorphous amorphous layer as the underlayer;
A mixed layer forming step of forming a mixed layer of the same material as the amorphous layer;
A non-crystalline part removing step of removing a part of the non-crystalline layer and the non-crystalline part;
Heating the remaining part of the non-crystalline layer and the crystalline part to form an integral crystalline layer;
A method for manufacturing a semiconductor light emitting device, comprising: In the manufacturing method of the semiconductor light-emitting device according to any one of claims 1 to 6,
The uneven shape forming step includes:
A mixed layer forming step of forming a mixed layer using the group III nitride semiconductor layer as the base layer;
Removing the non-crystalline portion from the mixed layer to expose the remainder of the group III nitride semiconductor layer and the crystalline portion; and
A semiconductor etching step of forming a recess by dissolving the remaining portion of the exposed group III nitride semiconductor layer by etching;
An uneven layer forming step of forming an uneven layer in the crystal part and the recess,
A method for manufacturing a semiconductor light emitting device, comprising: In the manufacturing method of the semiconductor light emitting element according to claim 14,
The uneven shape forming step includes:
A heating step of heating the crystal portion and the concavo-convex layer at a temperature within a range of 200 ° C. or higher and 800 ° C. or lower to make the crystal portion and the concavo-convex layer as an integrated crystal layer. Production method. In the manufacturing method of the semiconductor light-emitting device according to any one of claims 1 to 6,
In the mixed layer forming step,
A mixed layer is formed using a sapphire substrate as the base layer,
In the non-crystal part removing step,
A method of manufacturing a semiconductor light emitting device, wherein the remaining portion of the sapphire substrate and the crystalline portion are exposed by removing the amorphous portion. In the manufacturing method of the semiconductor light emitting element according to claim 16,
The uneven shape forming step includes:
After the non-crystalline part removing step,
A method for manufacturing a semiconductor light emitting device, comprising: a sapphire etching step in which an exposed portion of the exposed sapphire substrate is a recess by etching. In the manufacturing method of the semiconductor light-emitting device according to any one of claims 7 to 15,
The uneven shape forming step includes:
After forming the uneven shape,
A method for manufacturing a semiconductor light emitting device, comprising a patterning step of performing patterning. In the manufacturing method of the semiconductor light-emitting device according to any one of claims 1 to 18,
In the mixed layer forming step,
The film thickness of the mixed layer to be formed is in the range of 1000 to 5000 mm,
The film forming pressure is in the range of 0.1 Pa to 0.4 Pa,
The sputtering rate is in the range of 2 Å / sec to 10 Å / sec,
A method for manufacturing a semiconductor light emitting device.

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