JP2007281037A - Semiconductor light emitting element, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor light emitting element with a large light emission output, inexpensive, and with good productivity; and to provide its manufacturing method. <P>SOLUTION: The semiconductor light emitting element 1 has an active layer 8 serving as a light emitting layer, and electrode layers 5 and 7 formed on both sides of the active layer 8. At least one of the electrode layers 5 and 7 is a transparent electrode layer 5, and at least one of surfaces of the layer 5 has a texture form. If a particle diameter of the texture of the layer 5 is larger than λ/(4×n) (where λ refers to a wavelength with which luminous intensity of the element 1 is the maximum, and n refers to a refractive index of the transparent electrode layer 5), the light emission from the element 1 can be efficiently emitted to the surface of the element to increase the light emission output. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a semiconductor light emitting device and a method for manufacturing the same, and more particularly to a semiconductor light emitting device with improved light extraction efficiency and excellent mass productivity and a method for manufacturing the same.

  The external light emission efficiency of a semiconductor light emitting device having a pn or pin junction composed of a p-type semiconductor layer and an n-type semiconductor layer is generally determined by the internal light emission efficiency and the extraction efficiency of the emitted light. It is known that the internal light emission efficiency mainly depends on the quality of the epitaxial wafer for light emitting elements, and the light extraction efficiency to the outside largely depends on the structure and shape of the semiconductor light emitting element pellets. As means for improving the light emission output of this semiconductor light emitting device, technological development has been made with a focus on improving internal light emission efficiency by improving the quality of the wafer for the light emitting device and improving light extraction efficiency from the semiconductor light emitting device. I came.

As a method for improving the light extraction efficiency from a semiconductor light emitting element, for example, in Patent Document 1, a flat light-transmitting conductive electrode is formed on a p-type semiconductor layer, whereby light output from an electrode formation surface is increased. An improved structure is disclosed.
In Patent Document 2, a light-transmitting conductive electrode is formed on a semiconductor light-emitting element, and a dielectric thin film is formed directly thereon, thereby reducing the refractive index between the light-transmitting conductive electrode and the periphery of the element in a pseudo manner, Thus, a method for improving the light extraction efficiency by improving the translucency of the translucent conductive electrode is disclosed.
According to these techniques, it is possible to improve the current diffusibility of the diffusion current that contributes to the light emission, and it is possible to improve the light extraction efficiency by improving the light transmittance. However, since the transparent electrode layer is formed flat with respect to the flat surface, a part of the light emitted from the active layer is reflected by the transparent electrode layer and returns to the inside of the element, and the light extraction efficiency is improved. It was a hindrance to improvement.

  On the other hand, by making the surface of the semiconductor light emitting device chip uneven by a predetermined etching method, the probability that light is totally reflected at the interface between the light emitting surface and the outside can be reduced, and the light extraction efficiency can be improved. it can. Patent Document 3 discloses forming irregularities on the surface of an AlGaAs light emitting diode by wet etching. Patent Document 4 discloses that the surface of a GaAsP-based light emitting diode is formed with unevenness by wet etching. Patent Document 5 discloses that in a blue light-emitting diode, irregularities are formed on the surface of a p-type GaN contact layer, and a transparent electrode layer is formed thereon. According to these techniques, it is possible to improve the light extraction efficiency by increasing the light extraction surface area and reducing the reflection return of light into the device.

Japanese Patent No. 2941743 Japanese Patent No. 2588849 Japanese Patent No. 2780744 Japanese Patent No. 3531722 JP 2005-259970 A

  In the prior art described above, since the unevenness of the element surface is formed in the etching process, there is a problem that the cost is increased and the productivity is deteriorated.

  In view of the above problems, an object of the present invention is to provide a semiconductor light emitting device having a large light emission output, inexpensive and good in productivity, and a method for manufacturing the same.

In order to achieve the above object, a semiconductor light emitting device of the present invention is a semiconductor light emitting device having an active layer to be a light emitting layer and an electrode layer, and at least one of the electrode layers is a transparent electrode layer, and is transparent. At least one surface of the electrode layer has a texture shape.
In the above configuration, the texture particle diameter of the transparent electrode layer is preferably λ / (4 × n) or more (where λ is a wavelength at which the emission intensity of the semiconductor light emitting element is maximized, and n is the transparent electrode layer) The refractive index of
As a material for the transparent electrode layer, a material containing one or more of tin oxide, indium oxide, and zinc oxide is suitable. The transparent electrode layer preferably contains a material that enhances conductivity.
According to the said structure, the light emission output can be increased by providing a texture-shaped transparent electrode layer in the surface to a semiconductor light-emitting device.

The method for producing a semiconductor light emitting device of the present invention is a method for producing a semiconductor light emitting device having a textured transparent electrode layer, wherein the transparent electrode layer is deposited by chemical vapor deposition or physical vapor deposition.
In the above configuration, preferably, the transparent electrode layer is further subjected to a heat treatment step.
According to the above configuration, the surface of the transparent electrode layer of the semiconductor light emitting element can be textured during the film formation, so that an etching process such as RIE that makes the flat transparent electrode layer uneven is unnecessary. For this reason, a semiconductor light emitting device having a large light emission output can be manufactured at low cost.

ADVANTAGE OF THE INVENTION According to this invention, the extraction efficiency of light can be improved and the semiconductor light-emitting device with a large light emission output can be provided by coat | covering the electrode of a semiconductor light-emitting device with a texture-shaped transparent electrode layer.
According to the method for manufacturing a semiconductor light emitting device of the present invention, the surface of the transparent electrode of the semiconductor light emitting device is formed into a textured shape, so that a patterning step and an etching step by photolithography or the like are not required, and the cost is low. Thus, a semiconductor light emitting device with high luminance and excellent mass productivity can be manufactured with high yield.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, a first embodiment of the semiconductor light emitting device of the present invention will be described.
FIG. 1 is a cross-sectional view schematically showing a semiconductor light emitting device 1 according to the first embodiment of the present invention. As shown in FIG. 1, a semiconductor light emitting device 1 according to the present invention includes an active layer 8 serving as a light emitting layer and a pair of electrode layers 5 and 7 formed on both sides of the active layer 8. It is. Specifically, a pn junction composed of an n layer 3 and a p layer 4 is formed on the n-type substrate 2, a transparent electrode layer 5 formed on the p layer 4, and a part on the transparent electrode layer 5 And a p-electrode 6 serving as a bonding pad, and an n-electrode 7 formed on an n-type substrate. In the figure, the Y direction is the light emission direction.

A feature of the present invention is that at least one of the electrode layers 5 and 7 includes the transparent electrode layer 5 that transmits light emitted from the active layer 8. The surface of the transparent electrode layer 5 facing the active layer 8 has a texture shape. In the present invention, such a transparent electrode layer 5 is appropriately referred to as a texture transparent electrode.
Here, the pn junction may be a double heterostructure (hereinafter, referred to as a DH structure as appropriate) formed by the active layer 8 sandwiched between the n-layer 3 and the p-layer 4 as a cladding layer. In this case, the active layer 8 may be a layer (i layer, n ⁻ , p ⁻ ) to which no impurity is intentionally added.
Although the substrate 2 has been described as an n-type, it may be a p-type substrate 2 of the opposite conductivity type. In that case, the conductivity type of each layer may be changed according to the substrate.

  FIG. 2 is an enlarged schematic view showing a cross section of the transparent electrode layer 5 of FIG. As shown in FIG. 2, the surface of the transparent electrode layer 5 that faces the active layer 8 has a texture shape 5A with a rough surface. Thus, in the semiconductor light emitting device 1 of the present invention, at least one surface of the transparent electrode layer 5 has the texture shape 5A. The texture shape 5A is a granular shape having a pointed apex from the element inner side to the element surface side, that is, from the light emitting layer side to the light extraction side, and the texture transparent electrode 5 has a structure in which they are assembled. Have. In the illustrated case, the texture shape 5A shows a substantially triangular shape, but this shape may be various shapes. When the texture shape 5A is substantially uneven, it is preferable that the bottom of the concave portion and the upper portion of the convex portion are not flat and the reflection into the semiconductor light emitting element 1 is reduced.

As shown in FIG. 2, the particle size d _t of the texture shape 5A (hereinafter referred to as “texture particle size” as appropriate) is set to a size that satisfies the following equation (1).
d _t > λ / (4 × n) (1)
Here, λ is a wavelength at which the light emission intensity of the semiconductor light emitting element 1 is maximized, and n is a refractive index of the transparent electrode layer 5.
By setting the particle diameter _dt of the texture shape 5A to a wavelength at which the emission intensity of the semiconductor light emitting element 1 is maximum, that is, a diameter larger than 1 / (4 × n) of the peak emission wavelength, The reflection can be reduced and the light emission output of the semiconductor light emitting element 1 can be increased. However, the texture particle diameter d _t is 10μm or more, the effect of the texture shape for flatness of the electrode is increased is reduced undesirably. Furthermore, particularly high light emission output can be obtained by setting the thickness to 3 μm or less. In the present invention, when the emission wavelength of the semiconductor light emitting device 1 is 200 nm or more, the light output can be effectively increased. Furthermore, light can be efficiently extracted by making the refractive index n of the transparent electrode layer 5 smaller than the refractive index of the semiconductor layer used in the semiconductor light emitting device 1.

As the material of the transparent electrode layer 5, a material containing at least one of tin oxide (SnO ₂ ), indium oxide (In ₂ O ₃ ), zinc oxide (ZnO), and the like can be used. The transparent electrode layer may contain a material that enhances conductivity. Examples of such a material that enhances conductivity include Ga (gallium), Mg (magnesium), and Zn.

Next, a semiconductor light emitting element according to the second embodiment of the present invention will be described.
FIG. 3 is a cross-sectional view schematically showing a semiconductor light emitting device 1A according to the second embodiment of the present invention. As shown in FIG. 3, the semiconductor light emitting device 10 of the present invention has a structure in which the n substrate 2 of the semiconductor light emitting device 1 shown in FIG. 1 is removed. In this case, the semiconductor light emitting device 1 has the same structure as that of the semiconductor light emitting device 1 except that the pn junction is a thick layer of, for example, 100 μm. In this case, since light emission absorbed by the n-type substrate 2 can be reduced, light emission from the pn junction is easily emitted upward.

Next, a semiconductor light emitting element according to the third embodiment of the present invention will be described.
FIG. 4 is a cross-sectional view schematically showing a semiconductor light emitting element 15 according to the third embodiment of the present invention. As shown in FIG. 4, the semiconductor light emitting device 15 according to the present invention further has an ohmic junction layer 12 between the lower portion of the p electrode 6 and the p layer 4 as compared with the semiconductor light emitting device 1 shown in FIG. 1. It has the structure which formed. In this case, even if the ohmic resistance of the p layer 4 and the texture transparent electrode layer 5 is somewhat large, current can be passed through the ohmic junction layer 12 partially formed in the p layer 4, and the forward voltage rises. Can be suppressed. The ohmic bonding layer 12 includes one or more layers of Pt (platinum), Co (cobalt), Ni (nickel), Au (gold), or a layer made of two or more alloys selected from these layers. can do.

Next, a semiconductor light emitting element according to the fourth embodiment of the present invention will be described.
FIG. 5 is a cross-sectional view schematically showing a semiconductor light emitting device 20 according to the fourth embodiment of the present invention. As shown in FIG. 5, in the semiconductor light emitting device 20 of the present invention, the n-type substrate 2 of the semiconductor light emitting device 1 of FIG. 1 is a substrate 22 made of an insulator such as a sapphire substrate, and the texture transparent electrode layer 5 is a p layer. 4 is formed by inserting an ohmic junction layer 12. In this case, the ohmic junction layer 12 has a high light transmittance, that is, a thin layer so as not to hinder light emission. In this case, examples of the ohmic junction layer 12 include the above-described Pt, Co, Ni, Au, and the like. For example, a layer formed by stacking 50 Pt layers can be used as the ohmic junction layer 12. A layer in which a plurality of the above metals are stacked may be used as the ohmic junction layer 12. For example, a layer made of 25 Ｃｏ Co and 50 Ａｕ Au and a layer made of 25 Ｎｉ Ni and 50 Ａｕ Au can be used as the ohmic junction layer 12. As the ohmic junction layer 12, a conductive layer made of a transparent oxide such as InZnO ₂ , InGaMgO ₄ , or In ₂ MgO ₄ can also be used. Further, the n-electrode 7 is formed on the cut layer 3A with the n-layer exposed from the surface side. The semiconductor light emitting element 20 can be applied to an InGaN blue light emitting diode or the like.

Next, a semiconductor light emitting element according to a fifth embodiment of the present invention will be described.
FIG. 6 is a cross-sectional view schematically showing a semiconductor light emitting device 25 according to the fifth embodiment of the present invention. As shown in FIG. 6, the semiconductor light emitting device 25 of the present invention has a structure in which a second transparent electrode layer 26 having a high transmittance is further provided on the texture transparent electrode layer 5 of the semiconductor light emitting device 1 shown in FIG. It is said. If the refractive index of the second transparent electrode layer is made lower than the refractive index of the transparent electrode layer 5, the light extraction efficiency can be further improved. If the second transparent electrode layer 26 is a low resistance layer, the resistance of the entire transparent electrode layer 5 can be lowered.

Next, a semiconductor light emitting element according to a sixth embodiment of the present invention will be described.
7 and 8 are cross-sectional views schematically showing a semiconductor light emitting device 30 according to the sixth embodiment of the present invention.
As shown in FIG. 7, the semiconductor light emitting device 30 of the present invention is further provided with a reflective layer 31 on the texture transparent electrode layer 5 of the semiconductor light emitting device 10 shown in FIG. Is a structure in which a p-electrode 6 is provided. In this case, the light emitting surface is on the n layer side. As a material of the reflective layer 31, a material having a high reflectance at an emission wavelength such as Al (aluminum), Rh (rhodium), Ag, or the like may be used.
In this case, as shown in FIG. 8, an insulating layer 32 may be further inserted between the texture transparent electrode layer 5 and the reflective layer 31. A part of the texture transparent electrode layer 5 is provided with a p-electrode 6. If it does in this way, it can prevent that the metal of the reflective layer 31 reduces the oxygen contained in the texture transparent electrode layer 5, and the transmittance | permeability falls. As the insulating layer 32 _may be _{SiO 2, TiO 2, SiN,} SiON, Al 2 O 3, AlN or the like is used. In this case, a texture-shaped transparent electrode layer may be further formed on the surface on the n layer 7 side.
According to the semiconductor light emitting device 30 of the present invention, the light emitted to the lower portion of the active layer 8 can be reflected to the n layer 7 side by the reflective layer 31, further improving the light extraction efficiency. In this case, when a texture-shaped transparent electrode layer is formed also on the n layer 7 side, the light extraction efficiency is further improved.

  FIG. 9 is a cross-sectional view schematically showing another modification of the semiconductor light emitting device according to the sixth embodiment of the present invention. As shown in FIG. 9, in the semiconductor light emitting element 35, an insulating layer 32 is inserted between the texture transparent electrode layer 5 and the reflective layer 31. According to the semiconductor light emitting device 35 of the present invention, the light emitted to the lower part of the active layer 8 can be reflected to the substrate 22 side by the reflective layer 31, so that the light extraction efficiency is further improved.

Also in the second to sixth embodiments, the structure of the texture transparent electrode layer 5 is the same as that of the semiconductor light emitting device 1 according to the first embodiment, and the operation thereof is also the same. The semiconductor light emitting devices 10, 15, 20 , 25, 30, 35 can significantly increase the light emission output above the surface (Y direction in FIGS. 3 to 9).
The material used for the semiconductor light emitting devices 1, 10, 15, 20, 25, 30, and 35 of the present invention may be any material that can emit light of infrared, visible light, and ultraviolet wavelengths. For example, AlGaAs, AlGaInP, GaP, AlInGaN, InGaN, and other various compound semiconductors can be used.
The semiconductor light emitting elements 1, 10, 15, 20, 25, 30, and 35 of the present invention shown in FIGS. 1 and 3 to 7 are further mounted in a package. The light emission output can be further increased by covering with a lens made of an epoxy resin having a refractive index larger than that of the air. It is preferable that the refractive index of this lens is smaller than the refractive index of the texture transparent electrode layer 5 because the light emission output can be increased.

Next, the manufacturing method of the semiconductor light emitting device of the present invention will be described.
In the first to sixth embodiments, first, a pn junction or a double heterostructure that becomes an operation layer of the semiconductor light emitting element is deposited on the substrates 2 and 22 by an epitaxial growth method.

Next, the roughened transparent electrode layer 5 is deposited on the p-layer 4 on the substrate surface side by CVD (chemical vapor deposition), PVD (physical vapor deposition), electrodeposition, or the like. At this time, the texture transparent electrode layer 5 can be formed by increasing the film forming speed. In the conventional transparent electrode layer, the film forming conditions necessary for obtaining a flat surface are, for example, a substrate temperature of 200 ° C. or higher and a film forming speed of about 1 cm / sec in a vacuum of 3 × 10 ⁻⁴ Torr or higher. It is said. In the texture transparent electrode layer 5 of the present invention, by increasing the film forming rate to 10 Å / sec, aggregation of the transparent electrode material can be promoted, and the transparent electrode layer 5 can be made into a texture shape. In forming the transparent electrode layer 5, the film forming process may be performed by changing the film forming speed. For example, the transparent electrode layer 5 may be formed into a texture shape by depositing 1000 Å (100 nm) at a deposition rate of 1 Å / sec and then depositing 2000 Å (200 nm) at a deposition rate of 10 Å / sec. In this case, after forming the flat layer first on the transparent electrode layer 5, the texture shape on the surface is formed, so that the grain size in the texture shape can be easily increased, and the light extraction efficiency can be improved. Can be improved.

The texture transparent electrode layer 5 is subjected to heat treatment in an inert gas atmosphere such as Ar or N ₂ or vacuum at 400 ° C. or more and 700 ° C., thereby further improving the crystallinity of each grain in the texture transparent electrode and increasing the transparency. The resistance of the texture transparent electrode layer 5 can be lowered. In this case, the heat treatment temperature and the heat treatment time may be the emission wavelength in the semiconductor light emitting device 1 of the present invention so that the transparency of the texture transparent electrode layer 5 is increased. The heat treatment time may be a heat treatment between 10 minutes and less than 10 hours. When the heat treatment time is 10 minutes or less, the improvement in transparency and the reduction in resistance are insufficient, which is not preferable. On the other hand, if the heat treatment time is 10 hours or longer, the heat load on the semiconductor element increases and the light output may decrease, which is not preferable.

Finally, by forming the p electrode 6 and the n electrode 7, the semiconductor light emitting device of the present invention can be manufactured.
A bonding pad made of Au or the like may be further formed on the p-electrode 6 and the n-electrode 7. The semiconductor light emitting device 10 can be manufactured by epitaxially growing a relatively thick pn junction on the substrate and then removing the substrate by etching. In this case, the n electrode may be formed on the n layer 3.

  Thereby, according to the manufacturing method of the semiconductor light-emitting device of the present invention, it is possible to form the rough textured transparent electrode layer 5 without performing the patterning step and the etching step by photolithography. For this reason, the process of etching the surface of the transparent electrode layer 5 becomes unnecessary, and the semiconductor light emitting elements 1, 10, 15, 20, 25, 30, and 35 can be manufactured in a short time and the cost thereof can be reduced. Can do.

Examples of the semiconductor light emitting device of the present invention will be described below.
First, a method for manufacturing the red vertical cavity light emitting diode of Example 1 will be described.
The semiconductor light emitting device 1 shown in FIG. 1 is composed of a double heterojunction having a black reflective layer made of GaAs and GaAlAs, a clad layer made of AlGaInP, and an active layer 8 made of i-InGaP on an n-type GaAs substrate 2. A vertical cavity light emitting diode was manufactured. A texture transparent electrode layer 5 was formed on the outermost surface of the p layer 4.

The texture transparent electrode layer 5 having a thickness of 300 nm was formed of an ITO film. The ITO film was formed by vacuum deposition using tin oxide and indium tin as materials. The degree of vacuum during vacuum deposition was 1 × 10 ⁻⁴ Pa, and the substrate was heated to 200 ° C. The texture particle size of the transparent electrode layer 5 was able to be 0.16 μm by setting the film forming rate to 15 Å / sec, which is higher than 2 Å / sec when obtaining a normal flat surface. In this case, the formed ITO film was further heat-treated at 400 ° C. for 2 hours in a nitrogen atmosphere to reduce ohmic resistance. The texture particle size of the transparent electrode layer 5 was determined by measuring the distance between the recesses with an atomic force microscope. An n electrode 7 made of Ni / Au—Ge / Au is formed on the n substrate 2, and an electrode to be a bonding pad is formed of Ni / Pt / Au on a part of the texture transparent electrode layer 5. did.

As a semiconductor light emitting device of Example 2, a blue light emitting diode 20 shown in FIG. 4 was manufactured. On the sapphire substrate 22, an InGaAlN double heterojunction structure having a composition with an emission wavelength of 460 nm was produced by an epitaxial growth method, and a thin ohmic junction layer 12 was first formed on the p layer 4.
Next, a transparent electrode layer 5 having a texture shape was deposited in the same manner as in Example 1 except that the film formation rate was 10 Å / sec and the heat treatment was performed at 700 ° C. for 10 minutes. The grain size of the texture transparent electrode layer 5 was 0.12 μm.
Here, in the region 3A where the n electrode is formed in the n layer, the epitaxially grown growth layer is etched by a mask process or the like to expose the n layer electrode forming region 3A, and after Ti / Al is deposited, heat treatment is performed. The n electrode 7 was formed. Further, bonding pads made of Ti / Pt / Au were formed on the texture transparent electrode layer 5 and the n-electrode 7.

(Comparative Example 1)
Next, a comparative example will be described.
A red semiconductor light emitting device of Comparative Example 1 was manufactured in the same manner as in Example 1 except that the film forming rate was set to 1 cm / sec in order to obtain a flat transparent electrode layer instead of the texture transparent electrode layer 5.

(Comparative Example 2)
A blue semiconductor light emitting device of Comparative Example 2 was manufactured in the same manner as in Example 2 except that the film forming rate was 1 Å / sec in order to obtain a flat transparent electrode layer instead of the texture transparent electrode layer 5. In this case, as in Comparative Example 1, the outermost surface of the transparent electrode layer was a flat surface with no irregularities. Table 1 shows the conditions for forming the transparent electrode layer in Examples 1 and 2 and Comparative Examples 1 and 2 described above.

Next, the light emission characteristics of the semiconductor light emitting devices of Examples and Comparative Examples will be described.
Table 2 shows the texture-shaped particle size (μm), the peak light emission wavelength (nm), and the light emission output (mW) of the light emitting diode in the transparent electrode layer 5 of Examples and Comparative Examples. The emission wavelength and the emission output are values measured at a forward current of 20 mA. Here, the light emission output was measured using an integrating sphere.

  As is clear from Table 1, the emission peak wavelengths of Example 1 and Comparative Example 1 are both 646 nm, and the light emission outputs of the semiconductor light emitting devices of Example 1 and Comparative Example 1 are 1.36 mW, 1. It was 25 mW. From this, it has been found that the light emission output of the red semiconductor light emitting device of Example 1 having the texture transparent electrode layer 5 is increased.

  Both the emission peak wavelengths of Example 2 and Comparative Example 2 were 461 nm, and the emission outputs of Example 2 and Comparative Example 2 were 3.35 mW and 3.14 mW, respectively. From this, it was found that the light emission output of the blue semiconductor light emitting device of Example 2 having the texture transparent electrode layer 5 was increased.

  According to the above-described Examples and Comparative Examples, it has been found that the light emission output of the semiconductor light emitting device having the texture transparent electrode layer 5 of the present invention can be improved. That is, according to the present invention, it has been found that the light emission output can be improved by about 10% in any of the red light emitting diode and the blue light emitting diode without increasing the number of manufacturing steps.

  The present invention is not limited to the film forming method of the texture transparent electrode layer in the semiconductor light emitting device described in the above embodiment, and any method may be used, and various methods can be used within the scope of the invention described in the claims. Needless to say, variations are possible and are within the scope of the present invention.

1 is a cross-sectional view schematically showing a semiconductor light emitting element according to a first embodiment of the present invention. FIG. 2 is an enlarged schematic view showing a cross section of the transparent electrode layer in FIG. 1. It is sectional drawing which shows typically the semiconductor light-emitting device concerning the 2nd Embodiment of this invention. It is sectional drawing which shows typically the semiconductor light-emitting device concerning the 3rd Embodiment of this invention. It is sectional drawing which shows typically the semiconductor light-emitting device concerning the 4th Embodiment of this invention. It is sectional drawing which shows typically the semiconductor light-emitting device concerning the 5th Embodiment of this invention. It is sectional drawing which shows typically the semiconductor light-emitting device concerning the 6th Embodiment of this invention. It is sectional drawing which shows typically the modification of the semiconductor light-emitting device concerning the 6th Embodiment of this invention. It is sectional drawing which shows typically the another modification of the semiconductor light-emitting device concerning the 6th Embodiment of this invention.

Explanation of symbols

1, 10, 15, 20, 25, 30, 35: Semiconductor light emitting device 2: Substrate 3: n layer 3A: cut region 4: p layer 5: texture transparent electrode layer 5A: texture 6: p electrode (bonding pad)
7: n electrode 8: active layer (i layer)
12: Ohmic junction layer 22: Substrate (insulating substrate)
26: Second transparent electrode layer 31: Reflective layer 32: Insulating layer

Claims (6)

A semiconductor light emitting device having an active layer to be a light emitting layer and an electrode layer,
At least one of the electrode layers is a transparent electrode layer, and at least one surface of the transparent electrode layer has a texture shape.   The texture particle diameter of the transparent electrode layer is not less than λ / (4 × n) (where λ is a wavelength at which the emission intensity of the semiconductor light emitting element is maximized, and n is a refractive index of the transparent electrode layer). The semiconductor light-emitting device according to claim 1, wherein   3. The semiconductor light-emitting element according to claim 1, wherein the material of the transparent electrode layer includes one or more of tin oxide, indium oxide, and zinc oxide.   The semiconductor light-emitting element according to claim 3, wherein the transparent electrode layer contains a material that enhances conductivity. A method of manufacturing a semiconductor light emitting device having a textured transparent electrode layer,
A method for producing a semiconductor light emitting device, comprising the step of depositing the transparent electrode layer by chemical vapor deposition or physical vapor deposition. 6. The method of manufacturing a semiconductor light-emitting element according to claim 5, further comprising a step of performing a heat treatment on the transparent electrode layer.

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