JP2008010546A - Semiconductor light-emitting element and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inexpensively manufacture a high-luminance semiconductor light-emitting element by achieving use of a metal oxide transparent conductive film, while generating a semiconductor light-emitting element along with suppressing a reaction between the metal oxide transparent conductive film and a semiconductor on the surface of a light-emitting element, in order to improve a light transmittance and to reduce resistance in the semiconductor light-emitting element that has a structure using the metal oxide transparent conductive film as a current diffusion layer. <P>SOLUTION: The semiconductor light-emitting element has a semiconductor substrate, a light-emitting-layer forming part provided on the semiconductor substrate, a window layer provided at the upper part of the light-emitting-layer forming part so as to constitute a light extraction face, a first optically-transparent layer provided on the window layer, and a second optically-transparent layer of a conductive film that is provided on the first optically-transparent layer. The first optically-transparent layer is provided as a diffusion preventing film for preventing constituent atoms of the second optically-transparent layer from being diffused on the window-layer side. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a semiconductor light emitting element including a light emitting layer made of a semiconductor such as AIGaAs, AIGaInP, or GaN, and a method for manufacturing the same.

In recent years, AIGaInP-based crystals can be grown by MOVPE (Metal Organic Vapor Phase Epitaxy) while controlling the concentration and thickness of semiconductor light-emitting elements with high precision. It has become.
As a result, the light emission characteristics have been greatly improved, and it has become possible to manufacture a high-luminance semiconductor light-emitting element, such as an LED (light-emitting diode).
However, in order to obtain high luminance of the semiconductor light emitting device, it is necessary to increase the thickness of the window layer (current diffusion layer) to improve current diffusion into the LED.

For this reason, the epitaxial growth time by MOVPE becomes long, and there exists a problem that the manufacturing cost of the wafer for LED becomes high.
In order to suppress the increase in the cost, it is necessary to make the window layer thin, reduce the resistivity of the window layer, and improve the current diffusion into the LED.
Therefore, a method of using a material capable of obtaining a low resistivity for the window layer is generally used. For example, in the case of the AIGalnP system, a compound semiconductor material such as AIGaAs or GaP is used as the window layer. (See Patent Document 1)

However, as shown in Patent Document 1, even when a low resistivity material is used for the window layer forming material, the thickness of the window layer is set to 5 μm or more in order to improve current diffusion into the LED. The thickness needs to be increased, and the manufacturing cost cannot be reduced.
In the manufacturing method described above, in order to make the window layer thinner, it is necessary to further reduce the resistivity of the window layer. However, as the window layer can be made thinner than the above-described thickness, the mobility is increased or the carrier concentration is increased. It is difficult to do.

As a means for solving this problem, a structure using an ITO (Indium Tin Oxide) film of a metal oxide transparent conductive film instead of the window layer is known.
That is, a technique is used in which the light extraction surface on the outermost surface of the light emitting element is covered with an ITO film, the resistance of the window layer apparently lowered with this ITO film, and current diffusion in the window layer is improved (for example, Patent Document 2). reference). By using this ITO film as a current diffusion film, the epitaxial layer for the window layer can be eliminated, the epitaxial growth time by MOVPE can be reduced, and the manufacturing cost of the semiconductor light emitting device can be reduced.
USP 5008718 Japanese Unexamined Patent Publication No. 01-225178

However, when a metal oxide transparent conductive film is used for a light emitting device, the metal oxide transparent conductive film is formed at a high temperature in order to increase the transmissivity of the transparent conductive film itself and decrease the resistivity, or It is necessary to perform high temperature treatment after film formation.
However, when the metal oxide transparent conductive film is formed on the semiconductor on the surface of the semiconductor light emitting device and then subjected to a high temperature treatment for improving the light transmittance and reducing the resistivity, There is a drawback that a reaction occurs between the semiconductor layer adjacent to the transparent conductive film, the light transmittance of the metal oxide transparent conductive film is further lowered, and the brightness of the light emitting element is lowered.

Therefore, if the formation temperature of the metal oxide transparent conductive film is lowered, the transmissivity of the metal oxide transparent conductive film cannot be increased sufficiently or cannot be sufficiently lowered, and the metal oxide transparent conductive film cannot be sufficiently reduced. There is a problem that the effect of forming the film cannot be obtained.
The present invention has been made in view of such circumstances. In a semiconductor light emitting device having a structure using a metal oxide transparent conductive film as a current diffusion layer, the metal oxide transparent conductive film and the semiconductor on the surface of the light emitting element are provided. It is possible to produce a high-brightness semiconductor light-emitting element at low cost by suppressing the reaction of the light-emitting element, improving the light transmittance, reducing the resistance, and enabling the use of a metal oxide transparent conductive film. There is.

  In order to solve the above-described problems, a semiconductor light emitting device of the present invention includes a semiconductor substrate, a light emitting layer forming portion provided on the semiconductor substrate, and a window provided on the light emitting layer forming portion and constituting a light extraction surface. A first light-transmitting layer provided on the window layer, and a second light-transmitting layer that is a conductive film provided on the first light-transmitting layer. And the first light transmissive layer is provided as a diffusion preventing film that prevents the constituent atoms of the second light transmissive layer from diffusing toward the window layer side.

  In the semiconductor light emitting device of the present invention, the first light transmissive layer is transmissive to the light emitted from the light emitting layer forming portion, such as titanium oxide (TiOx), silicon nitride (SiN), silicon oxide ( It is characterized by comprising one or more layers of SiOx) and zirconium oxide (ZrO).

  In the semiconductor light emitting device of the present invention, the second light transmission layer is a film having conductivity, and is a mixture of indium oxide (In2O3) and tin oxide (SnO2) (ITO), indium oxide (InO), oxidation It is characterized by comprising one or more layers of tin (SnO), zinc oxide (ZnO), and nickel oxide (NiO).

  In the semiconductor light emitting device of the present invention, the first and second light transmission layers are each formed with a thickness of 10 nm to 1 μm.

  The semiconductor light emitting device of the present invention is provided with a through hole penetrating the first and second light transmissive layers, and the through hole from above the first light transmissive layer and the second light transmissive layer. And a plurality of island-shaped contact electrodes that are in ohmic contact with the window layer.

  The semiconductor light emitting device of the present invention is characterized in that a through hole of the first light transmissive layer and the second light transmissive layer is not formed immediately below the pad electrode for wire bonding.

  In the semiconductor light emitting device of the present invention, the total area of the through holes in a plan view is 1% or more and 3% or less of the effective light emitting area of the semiconductor light emitting device.

  The semiconductor light emitting device of the present invention is characterized in that the through hole is formed as a circle having a diameter of 5 μm or less or a polygon having a side length of 5 μm or less in plan view.

  The semiconductor light emitting device of the present invention is characterized in that the surface of the first light transmitting layer is a flat surface or has an uneven shape.

  The method for manufacturing a semiconductor light emitting device of the present invention includes a step of forming a light emitting layer forming portion on a semiconductor substrate, a step of forming a window layer constituting a light extraction surface on the light emitting layer forming portion, and the window layer. A step of forming a first light-transmitting layer, and a step of forming a second light-transmitting layer, which is a conductive film, on the first light-transmitting layer; The first light-transmitting layer is formed as a diffusion preventing film that prevents constituent atoms of the second light-transmitting layer from diffusing to the window layer side.

  That is, the present invention includes a semiconductor layer (window layer) having a plurality of semiconductor layers for light emission and constituting a light extraction surface, and a first light for suppressing reaction provided on the semiconductor layer. A transmissive layer, a second light transmissive layer provided on the first light transmissive layer, and a contact penetrating the first and second light transmissive layers and reaching the light extraction surface A semiconductor light emitting device comprising a hole, and an electrode (contact electrode) electrically connecting the semiconductor layer and the second light transmissive layer through the contact hole It is related to.

  As described above, according to the present invention, in the semiconductor light emitting device, the reaction temperature at which the reaction suppression layer disposed between the semiconductor substrate and the transparent conductive layer causes alloying of the transparent electrode layer and the window layer is increased. Because it is formed with a composition of atoms that is higher than the temperature at which the resistance of the transparent electrode layer is reduced, it is a barrier layer that suppresses alloying by the constituent atoms of the transparent electrode layer and the window layer. Even when the transparent conductive layer is formed at a high temperature or through a high-temperature heat treatment in the element process, the reaction of each material atom at the interface between the window layer and the transparent conductive layer is suppressed, and the window layer and the transparent conductive layer in the semiconductor substrate are suppressed. In order to prevent alloying with the layer and suppress a decrease in the light transmittance of the transparent electrode layer, it is possible to obtain better luminance characteristics as compared with the conventional example.

Hereinafter, a semiconductor light emitting device (double heterojunction semiconductor light emitting device 10) according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a conceptual diagram showing a configuration example of a cross-sectional structure of the semiconductor light emitting device according to the embodiment. FIG. 2 is a conceptual diagram showing a configuration example of a planar structure in plan view of the semiconductor light emitting device according to the embodiment. 1 is a cross-sectional view taken along the solid line A in FIG.
In this figure, a double heterojunction semiconductor light emitting device 10 includes an N substrate 11 (N type semiconductor substrate), an N type cladding layer 12, an active layer 13, a P type cladding layer 14, a window layer 15, a cathode electrode 17, a transparent conductive material. A layer 18, a reaction suppression layer 19, a contact electrode 20, and an anode electrode 21 are included. In addition, the N substrate 11, the N-type cladding layer 12, the active layer 13, the P-type cladding layer 14, and the window layer 15 are referred to as a semiconductor substrate 16 in this embodiment.

In the semiconductor light emitting device 10 of the present invention, an N-type cladding layer 12 is formed on one surface (surface in the upper direction in the drawing) of an N-type substrate 11 which is an N-type semiconductor substrate.
The N-type cladding layer 12 is composed of a semiconductor layer such as aluminum-gallium-indium-phosphorus (AIGaInP). The N-type cladding layer 12 is formed by, for example, an epitaxial growth method and is provided with an impurity concentration of about 5 × 10 ¹⁷ cm ^{−3 and} a thickness of about 2 μm.

The active layer 13 is formed on the N-type cladding layer 12 and is composed of a semiconductor layer made of AIGaInP or the like as a forming material. The active layer 13 is formed by, for example, an epitaxial growth method, and is provided with a thickness of about 0.5 μm. The active layer 13 is a light-emitting layer that emits light by electroluminescence, and carriers (holes and electrons) injected from the N-type cladding layer 14 and the P-type cladding layer 12 provided on both sides of the active layer 13. ) Recombine and light emission occurs.
Further, in FIG. 1, the active layer 13 is shown as a single layer to simplify the illustration, but as an actual configuration, a well-known multi-quantum well (MQW) structure, Or you may have a single quantum well (SQW: Single-Quantum-Well) structure.

The P-type cladding layer 14 is formed on the active layer 13 and is composed of a semiconductor layer made of AIGaInP or the like as a forming material. The P-type cladding layer 14 is formed by, for example, an epitaxial growth method, and is provided with an impurity concentration of about 5 × 10 ¹⁷ cm ^{−3 and} a thickness of about 2 μm.
Here, the composition ratio of Al (aluminum) in AIGaInP constituting the N-type cladding layer 12 and the P-type cladding layer 14 is set to be larger than the composition ratio of Al in AIGaInP constituting the active layer 13. .

By setting the Al composition ratio as described above, light generated by carrier recombination in the active layer 13 can be efficiently extracted outside the active layer 13.
A window layer 15 may be formed on the P-type cladding layer 14. The window layer 15 is composed of a semiconductor layer such as gallium-phosphorus (GaP) into which a P-type impurity is introduced. The window layer 15 is formed by, for example, an epitaxial growth method, and is provided with an impurity concentration of about 5 × 10 ¹⁷ cm ^{−3 and} a thickness of about 2 μm. Here, the window layer 15 constitutes one surface (external surface) of the semiconductor substrate 16, and constitutes an external extraction surface of light emitted from the active layer 13.

On the other surface of the N-type substrate 11, an electrode 17 composed of a gold-germanium alloy (Au—Ge) film or a metal multilayer film made of nickel (Ni) or gold (Au) is provided. Yes.
On the other hand, a transparent conductive layer 18 is formed on the surface of the semiconductor light emitting element 10. The transparent conductive layer 18 includes a mixture (ITO) of indium oxide (In2O3) and tin oxide (SnO), indium oxide (InO), tin oxide (SnO), zinc oxide (ZnO), nickel oxide (NiO), and the like. At least one layer selected from these materials, that is, any one layer or a composite layer obtained by combining a plurality of selected layers.

  Further, the transparent conductive layer 18 is made of the above-described inorganic dielectric material having a transparency that transmits the light emitted from the active layer 13 and having a predetermined thickness. Here, it is desirable that the transparent conductive scabbard 18 has a thickness of 10 nm to 1 μm. That is, since the transparent conductive layer 18 has a thickness of 10 nm or more, the current can be spread (diffused) well. Moreover, the transparent conductive layer 18 can suppress the attenuation of light by limiting the thickness to 1 μm or less, and can improve the light extraction efficiency.

  The reaction suppression layer 19 is provided (interposed) between the window layer 15 and the transparent conductive layer 18. The reaction suppression layer 19 includes at least one layer selected from titanium oxide (TiO), silicon nitride (SIN), silicon oxide (SiOx), zirconium oxide (ZrO), and the like, that is, any one layer or It is composed of a composite layer in which a plurality of selected layers are combined. Moreover, the reaction suppression layer 19 is made of an inorganic dielectric material having a transparency that transmits the light emitted from the active layer 13 and having a predetermined thickness.

Here, each of the above-described materials (and combinations thereof) for forming the reaction suppression layer 19 is different in formation temperature from the material for forming the window layer 15 (GaP in this embodiment), so that no alloying reaction occurs. Material. That is, the resistivity of the transparent conductive layer 18 is reduced compared to the reaction temperature at the interface between the transparent conductive layer 18 and the reaction suppression layer 19 (alloying occurs) and the reaction temperature at the interface between the reaction suppression layer 19 and the window layer 15. Since the temperature at which the high temperature treatment is performed is low, alloying can be suppressed between the respective interfaces.
For this reason, the reaction suppression layer 19 becomes a barrier layer that suppresses the reaction of the forming material at the interface between the transparent conductive layer 18 and the window layer 15, and can prevent a decrease in the transmittance of the transparent conductive layer 18. Since the emitted light can be emitted efficiently, the luminance characteristics of the semiconductor light emitting element 10 can be improved as compared with the conventional case.

  The reaction suppression layer 19 preferably has a thickness of 10 nm to 1 μm. That is, the reaction suppression layer 19 has a thickness of 10 nm or more, thereby suppressing the reaction of atoms at the interface between the semiconductor substrate 16 and the transparent conductive layer 18 and preventing alloying. Further, by limiting the thickness of the reaction suppression layer 19 to 1 μm or less, attenuation of transmitted light can be reduced, and light extraction efficiency can be improved.

  The reaction suppression layer 19 and the transparent conductive layer 18 are provided with a plurality of through-holes 20 a that pass through both layers perpendicular to the surface and reach the surface of the window layer 15. Each of the through holes 20a is formed of a metal multilayer film made of titanium-gold-beryllium-titanium (Ti-Au-Be-Ti), titanium-gold-chromium (Ti-Au-Cr), and gold (Au). A contact electrode 20 is formed. That is, since the reaction suppression layer 19 is an insulator, it is necessary to form the through hole 20 a in this way and to contact the semiconductor substrate 16 from the outside using the contact electrode 20. The contact electrode 20 is an island-shaped contact electrode that makes ohmic contact with the window layer 15.

  The contact electrode 20 is necessary for making contact with the semiconductor substrate 16 through the through hole 20a. However, since the contact electrode 20 serves as a shielding layer against emitted light, the contact electrode 20 has a planar area in a plan view of the through hole 20a. It is necessary to form such that the total value is 1% or more and 5% or less of the effective light emitting area of the semiconductor light emitting device 10, and more preferably 1% or more and 3% or less. In the case of forming with the total value of the above areas, the ratio of shielding the emitted light is increased, and the luminance value of the semiconductor light emitting element is lowered.

Further, when formed with the total value of the following areas described above, the contact resistance between the contact electrode 20 and the semiconductor substrate 16 increases, and the driving voltage for light emission of the semiconductor light emitting element 10 is increased. Will end up.
In addition, since a larger number of small contact electrodes 20 are arranged in a dispersed manner, the effect of diffusing current over the entire surface of the light emitting substrate 16 is increased, so the through hole 20a has a circular shape with a diameter of 5 μm or less, or one side. It is necessary to arrange a plurality of polygons with a predetermined distance in an average of the number of polygons having a length of 5 μm or less at a predetermined distance.

  As shown in the plan view of the plan view of FIG. 2, a substantially central portion on the plane of the transparent conductive layer 18 includes gold-beryllium-titanium (Au—Be—Ti), gold-chromium (Au—Cr), and gold ( An anode electrode 21 made of a metal multilayer film made of Au) or the like is provided in a substantially circular shape. It is desirable that the through hole 20a is not provided (not formed) immediately below the anode electrode 21. That is, by providing the through-hole 20a immediately below the anode electrode 21, the anode electrode 21 and the window layer 15 are connected, a current flows immediately below the anode electrode 21, and light is emitted near the anode electrode 21. Become.

However, as already described, by providing the through-hole 20a immediately below the anode electrode 21, the anode electrode 21 becomes a shielding layer against the emitted light emitted from the active layer 13, so that the light emission of the semiconductor light emitting element 10 is achieved. The luminance characteristics of the image will be degraded. Further, by providing the through hole 20a immediately below the anode electrode 21, the current for light emission is concentrated immediately below the anode electrode 21, and the effect of diffusing the current over the entire plane of the active layer 13 is obtained. As a result, local light emission occurs, and the luminance characteristics of light emission of the semiconductor light emitting element 10 are deteriorated.
The anode electrode 21 is electrically connected to the contact electrode 20 through the transparent conductive layer 18.

Hereinafter, a method for manufacturing the semiconductor light emitting device according to the embodiment will be described with reference to FIGS. FIG. 3 shows a cross-sectional structure after formation of the reaction suppression layer 19 (first light transmission layer) and the transparent conductive layer (second light transmission layer) in the manufacturing process of the semiconductor light emitting device in one embodiment of the present invention. FIG. FIG. 4 is a conceptual diagram showing a cross-sectional structure after through holes are formed in the reaction suppression layer 19 and the transparent conductive layer in the manufacturing process of the semiconductor light emitting device in one embodiment of the present invention. FIG. 5 is a conceptual diagram showing a cross-sectional structure after forming a contact electrode through a through hole with respect to the reaction suppression layer 19 and the transparent conductive layer in the manufacturing process of the semiconductor light emitting device in one embodiment of the present invention.
Note that the manufacturing method described below is an example, and the manufacturing method is not limited to this method as long as a semiconductor light-emitting element having a similar structure can be obtained.

First, an N-type cladding layer 12, an active layer 13, a P-type cladding layer 14, and a window layer 15 are each formed on an N-type substrate 11 composed of GaAs doped with N-type impurities by an epitaxial growth method. Then, the layers are sequentially formed.
As the epitaxial growth method, a metal organic chemical vapor deposition (MOCVD) method, a molecular beam epitaxy (MBE) method, a chemical beam epitaxy (CBE) method, a molecular layer epitaxy (MLE) method, or the like can be used.

For example, when the low pressure MOCVD method is used, each semiconductor layer can be formed as follows.
An N-type cladding layer 12, an active layer 13, a P-type cladding layer 14, a window layer 15, and one surface of an N-type substrate 11 formed by adding an N-type impurity to GaAs are formed by MOCVD. Are successively formed by vapor phase epitaxial growth at a predetermined thickness.

Specifically, first, for example, TMA (trimethylaluminum), TEG (triethylgallium), TMIn (trimethylindium), and PH3 (phosphine) are used as source gases, and (AlxGa1-x) yIn1-yP. An N-type cladding layer 12 having a composition ratio (0.3 ≦ x ≦ 1) is formed.
Here, as the N-type dopant gas, for example, SiH4 (monosilane), Si2H6 (disilane), DESe (diethylselenium), DETe (diethyltellurium), or the like can be used.

Subsequently, using the same source gas continuously, for example, the composition ratio of (AlxGa1-x) yIn1-xP (0.2≤x≤1), which is lower than that of the N-type cladding layer 12, is set. The active layer 13 is formed. At this time, no dopant gas is used.
Next, continuously using the same source gas, a P-type cladding having a composition ratio of (AlxGa1-x) yIn1-yP (0.3≤x≤1), which is higher than that of the active layer 13 Layer 14 is formed.
Here, as a method for introducing the P-type impurity, for example, a dopant gas such as DEZn (diethyl zinc) can be used.

  Thereafter, the supply of TMA and TMIn as source gases is continuously stopped, TEG and PH3 source gases are introduced, and a window layer 15 composed of GaP doped with P-type impurities is formed. Through the above-described steps, the semiconductor substrate 16 shown in the light emitting semiconductor element 10 in FIG. 1 is obtained.

Next, as shown in FIG. 3, a reaction suppression layer 19 composed of titanium oxide or the like is formed on the window layer 15 by any film generation method such as vapor deposition, sputtering, plasma CVD, or sol-gel. Form.
As shown in FIG. 3, a transparent conductive film layer 18 made of ITO or the like is formed on the reaction suppression layer 19 by vapor deposition, sputtering, plasma CVD, sol-gel, or the like.

Thereafter, contact holes are patterned in the transparent conductive layer 18 and the reaction suppression layer 19 by a photolithography method or the like. As shown in FIG. 4, the transparent electrode layer 18 and the reaction control layer 19 penetrate through the window. A through-hole 20a reaching the layer 15 is formed.
Next, the transparent conductive layer 18 is made of Ti—Au—Be—Ti, Ti—Au—Cr, Au, or the like on the exposed surface (surface) of the window layer 15 exposed through the through hole 20a. A metal multilayer film or the like is deposited by vacuum evaporation or sputtering to form a metal film.

In order to form an electrode after forming the metal film, the metal film on the transparent conductive layer 18 is removed by using an etching method or the like, and a contact electrode 20 is formed as shown in FIG. The contact electrode 20 on the surface of the transparent electrode layer 18 overlaps with the through hole 20a in a plan view and is formed in a size including the through hole 20a.
Alternatively, the contact electrode 20 may be formed using a known lift-off technique after forming photolithography on the through hole 20a and forming the through hole. The through-hole 20a is filled with a metal multilayer film made of Ti—Au—Be—Ti, Ti—Au—Cr, Au, or the like.

Next, a metal multilayer film made of Au—Ti or the like is deposited on the transparent conductive layer 18 and the contact electrode 20 by a vacuum evaporation method or a sputtering method to form a metal film for forming the anode electrode 21.
Then, the metal film on the transparent conductive layer 18 is removed using an etching method or the like, and the anode electrode 21 is formed at a substantially central portion on the plane of the transparent electrode layer 18 as shown in FIG.

The anode electrode 21 may be made of the same material as that of the contact electrode 20, and the anode electrode 21 and the contact electrode 20 may be formed simultaneously or separately.
When formed at the same time, the number of electrode forming steps can be reduced, so that a light emitting element can be manufactured at a lower cost.
Next, an Au—Ge film or a metal multilayer film made of Au—Ge, Ni, Au, or the like is deposited on the exposed surface of the N-type substrate 11 by vacuum evaporation or sputtering to form the cathode electrode 16. .

The present invention is not limited to the configuration of the semiconductor light emitting device in the above-described embodiment. For example, the following modifications (1) to (5) are possible.
(1) Light reflection that improves the light emission efficiency by reflecting the emitted light emitted in the opposite direction between the N-type cladding layer 12 and the N-type substrate 11 and emitting it to the radiation side (upper method in FIG. 1). A metal layer can be inserted. Alternatively, the N-type substrate 11 may be removed, the light reflecting metal layer may be sandwiched, and a separately supported semiconductor substrate may be bonded.
(2) The conductivity type of each layer of the semiconductor substrate 16, that is, the N-type substrate 11, the N-type clad layer 12, the active layer 13, the P-type clad layer 14, and the window layer 15 is reversed from that in the embodiment. Can

(3) In FIG. 2, the contact electrodes 20 are not arranged at regular intervals, but may be arranged at regular intervals. By setting the same intervals, it is possible to obtain an effect of uniformly dispersing (diffusing) the current.
(4) In FIG. 1, the reaction suppression layer 19 has a flat surface (surface on the upper side in FIG. 1), but may have an uneven shape. Here, when the surface of the reaction suppression layer 19 has a concavo-convex shape, the light emitted from the active layer 13 is likely to enter the concavo-convex at a critical angle or less, so that the efficiency of extracting light emitted to the outside can be increased.

(5) The semiconductor light emitting device in the wood invention may be not only a completed semiconductor light emitting device but also a light emitting chip as an intermediate product (a state in which the through hole 20a and the contact electrode 20 are not formed).
In the above embodiment, the case where the semiconductor light emitting device 10 according to the present invention is applied to a light emitting diode (LED) has been described. However, the present invention is not limited to this, and any electroluminescent semiconductor light emitting device such as a semiconductor laser can be used. Applicable.

It is a conceptual diagram which shows the cross-section of the semiconductor light-emitting device by one Embodiment of this invention. It is a top view showing a planar structure in a plan view of a semiconductor light emitting device according to an embodiment of the present invention. In the manufacturing process of the semiconductor light-emitting device in one Embodiment of this invention, it is a conceptual diagram which shows the cross-sectional structure after formation of the reaction suppression layer 19 (1st light transmissive layer) and a transparent conductive layer (2nd light transmissive layer). is there. In the manufacturing process of the semiconductor light-emitting device in one Embodiment of this invention, it is a conceptual diagram which shows the cross-sectional structure after forming a through-hole with respect to the reaction suppression layer 19 and a transparent conductive layer. In the manufacturing process of the semiconductor light-emitting device in one Embodiment of this invention, it is a conceptual diagram which shows the cross-section after forming a contact electrode through a through-hole with respect to the reaction suppression layer 19 and a transparent conductive layer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Semiconductor light emitting element 11 ... N type board | substrate 12 ... N type clad layer 13 ... Active layer 14 ... P type clad layer 15 ... Window layer 16 ... Semiconductor substrate 17 ... Cathode electrode 18 ... Transparent conductive layer 19 ... Reaction suppression layer 20 ... Contact electrode 21 ... Anode electrode

Claims (10)

A semiconductor substrate;
A light emitting layer forming portion provided on the semiconductor substrate;
A window layer provided on the light emitting layer forming portion and constituting a light extraction surface;
A first light transmissive layer provided on the window layer;
A second light-transmitting layer that is a conductive film provided on the first light-transmitting layer;
The semiconductor light emitting element, wherein the first light transmissive layer is provided as a diffusion preventing film for preventing the constituent atoms of the second light transmissive layer from diffusing to the window layer side.   Titanium oxide (TiOx), silicon nitride (SiN), silicon oxide (SiOx), zirconium oxide (ZrO), wherein the first light transmissive layer is transmissive to light emitted from the light emitting layer forming portion. The semiconductor light-emitting device according to claim 1, comprising at least one of the layers.   The second light transmission layer is a conductive film, and is a mixture of indium oxide (In2O3) and tin oxide (SnO2) (ITO), indium oxide (InO), tin oxide (SnO), zinc oxide ( 3. The semiconductor light-emitting element according to claim 1, comprising at least one layer of ZnO) and nickel oxide (NiO).   4. The semiconductor light emitting element according to claim 1, wherein each of the first and second light transmission layers is formed with a thickness of 10 nm to 1 μm. 5.   A through hole penetrating the first and second light transmissive layers is provided, and the first light transmissive layer and the second light transmissive layer are passed through the through holes from above the window layer. 5. The semiconductor light emitting device according to claim 1, wherein a plurality of island-shaped contact electrodes that form ohmic contact are formed.   The through hole of the first light transmissive layer and the second light transmissive layer is not formed immediately below the pad electrode where wire bonding is performed. 6. Semiconductor light emitting device.   7. The semiconductor light emitting device according to claim 1, wherein a total area of the through holes in a plan view is 1% or more and 3% or less of an effective light emitting area of the semiconductor light emitting element. element.   8. The semiconductor light emitting device according to claim 1, wherein the through hole is formed as a circle having a diameter of 5 μm or less in a plan view or a polygon having a side length of 5 μm or less. .   9. The light emitting device according to claim 1, wherein the surface of the first light transmitting layer is a flat surface or has an uneven shape. 10. Forming a light emitting layer forming portion on a semiconductor substrate;
Forming a window layer constituting a light extraction surface on the light emitting layer forming portion;
Forming a first light transmissive layer on the window layer;
Forming a second light-transmitting layer, which is a conductive film, on the first light-transmitting layer,
The method of manufacturing a semiconductor light emitting element, wherein the first light transmissive layer is formed as a diffusion preventing film that prevents constituent atoms of the second light transmissive layer from diffusing toward the window layer side.

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