KR20090112854A - Group 3 nitride-based semiconductor light emitting diodes and methods to fabricate them - Google Patents

Abstract

PURPOSE: A group III nitride based semiconductor light emitting diode and a manufacturing method thereof are provided to improve luminance of a light emitting diode by minimizing total reflection of a light generated inside the light emitting diode. CONSTITUTION: A manufacturing method of a group III nitride based semiconductor light emitting diode comprises the following steps: a step for preparing a growth substrate for growing a light emitting structure; a step for forming the light emitting structure on the growth substrate; a step for forming a transparent ohmic contact current spreading layer on a top surface of the light emitting structure; a step for forming a wafer bonding layer on a top surface of the transparent ohmic contact current spreading layer; a step for preparing a patterned supporting substrate; a step for forming a flattening layer on a top surface of the patterned supporting substrate; a step for forming a wafer bonding layer on a top surface of the flattening layer; a step for forming a complex body by contacting the two wafer bonding layers; a step for separating the growth substrate from the complex body; a step for forming a p-type ohmic contact electrode and electrode pad(302) on a top surface of the transparent ohmic contact current spreading layer(206); and a step for forming a partial n-type electrode structure(301).

Description

Group 3 nitride-based semiconductor light emitting diodes and a method for manufacturing the same {group 3 nitride-based semiconductor light emitting diodes and methods to fabricate them}

The present invention relates to a group III-nitride semiconductor light emitting diode device capable of improving the overall performance of a light emitting diode device including a driving voltage and an external light emitting efficiency and a method of manufacturing the same. In other words, the present invention provides a wafer bonding between the patterned support substrate and the growth substrate on which the light emitting structure for the light emitting diode device is formed, the growth substrate lift-off, and the surface texture formed on the light emitting surface. The present invention provides a group III nitride semiconductor light emitting diode device having improved driving voltage and external light emitting efficiency and a method of manufacturing the same.

A light emitting diode (LED) device generates light by applying a current of a predetermined magnitude to convert current into light in an active layer in a solid light emitting structure. Early research and development of LED devices formed compound semiconductors such as indium phosphorus (InP), gallium arsenide (GaAs), and gallium phosphorus (GaP) with p-i-n junction structure. While the LED emits light in the visible light region longer than the wavelength of green light, the device that emits blue and ultraviolet light has also been commercialized recently, thanks to the research and development of the Group III nitride semiconductor material system. It is widely used in display devices, light source devices, and environmental application devices. Furthermore, a combination of three red, green, and blue LED device chips, or a short wavelength pumping LED device is used as a phosphor. A white light source LED for emitting white light by grafting has been developed, and its application range is widening as a lighting device. In particular, LED devices using solid single crystal semiconductors are highly efficient in converting electrical energy to light energy, have an average lifespan of more than 5 years, and can greatly reduce energy consumption and maintenance costs. It is attracting attention.

Since a light emitting diode (hereinafter, referred to as a group III nitride semiconductor light emitting diode) device made of such a group III nitride semiconductor is generally grown and manufactured on an insulating growth substrate (typically, sapphire), another group 3- Since two electrodes facing each other of the growth substrate cannot be provided like the Group 5 compound semiconductor light emitting diode device, two electrodes of the LED device must be formed on the crystal-grown semiconductor material system. The conventional structure of such a group III-nitride semiconductor light emitting diode device is schematically illustrated in FIG.

Referring to FIG. 18, the group III-nitride semiconductor light emitting diode device includes a lower nitride-based cladding layer 20 formed of a sapphire growth substrate 10 and an n-type conductive semiconductor material sequentially grown on the growth substrate 10. ), A nitride-based active layer 30 and an upper nitride-based cladding layer 40 made of a p-type conductive semiconductor material. The lower nitride-based cladding layer 20 includes n-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) layer 20a and the n-type In x Al y Ga 1 n-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) layer 20b having a different composition from the -xy N layer 20a, and the nitride-based active layer (30) is made of a semiconductor multilayer of nitride-based In x Al y Ga 1-xy N (0≤x, 0≤y, x + y≤1) composed of different compositions of multi-quantum well structure. Can be. In addition, the upper nitride-based cladding layer 40 includes a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) layer 40a and the p-type In x Al y. The Ga 1-xy N layer 40a may be composed of a p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) layer 40b having a different composition. In general, the lower nitride-based cladding layer / nitride-based active layer / upper nitride-based cladding layer 20, 30, or 40 formed of the group III-nitride semiconductor single crystal may be grown using an apparatus such as MOCVD or MBE. At this time, in order to improve lattice matching with the sapphire growth substrate 10 before growing the n-type In x Al y Ga 1-xy N layer 20a of the lower nitride-based cladding layer 20, AlN or GaN and The same buffer layer (not shown) may be formed therebetween.

As described above, since the sapphire growth substrate 10 is an electrically insulating material, both electrodes of the LED device should be formed on the same upper surface of the single crystal semiconductor growth direction. For this purpose, the upper nitride-based cladding layer 40 and the nitride-based A portion of the active layer 30 is etched (ie, etched) to expose a portion of an upper surface of the lower nitride-based cladding layer 20, and an upper surface of the exposed n-type In x Al y Ga 1-xy N layer 20. An n-type ohmic contacting interface electrode and electrode pad 70 are formed on the substrate.

In particular, since the upper nitride-based cladding layer 40 has a relatively high sheet resistance due to low carrier concentration and mobility, before forming the p-type electrode 60, There is a need for an additional material system that can form an ohmic contact current spreading layer. On the other hand, in US Pat. No. 5,563,422, the p-type electrode 60 is formed on the upper surface of the p-type In x Al y Ga 1-xy N layer 40b located at the uppermost layer of the light emitting structure for the group III nitride semiconductor light emitting diode device. Prior to the formation, a material system composed of Ni / Au was proposed to form an ohmic contact current spreading layer 50 which forms an ohmic contact interface having a low specific contact resistance in the vertical direction.

The ohmic contact current spreading layer 50 improves current spreading in the horizontal direction with respect to the p-type In x Al y Ga 1-xy N layer 40b while simultaneously providing a low specific contact resistance in the vertical direction. By forming an ohmic contacting interface having an effective current injection, the electrical characteristics of the light emitting diode device are improved. However, the ohmic contact current spreading layer 50 made of Ni / Au has a low transmittance of 70% on average even after the heat treatment, and this low light transmittance is large when the light emitted from the light emitting diode device is emitted to the outside. It absorbs a positive amount of light, reducing the overall external luminous efficiency.

As described above, in order to obtain a high-brightness light emitting diode device through the high light transmittance of the ohmic contact current spreading layer 50, in recent years, ohmic contact current soup formed of various opaque metals or alloys including the Ni / Au material system Instead of the redding layer 50, a method of forming a transparent conductive material such as indium tin oxide (ITO) or zinc oxide (ZnO), which has a transmittance of 90% or more, has been proposed. However, the transparent electroconductive material system has a small work function (4.7 to 6.1) compared to p-type In x Al y Ga 1-xy N (0≤x, 0≤y, x + y≤1) (~ 7.5 eV or more). eV), and a Schottky contact interface having a large specific contact resistance, rather than an ohmic contacting interface, after direct deposition on the p-type In x Al y Ga 1-xy N layer 40b and subsequent processing including heat treatment. contacting interfaces, new transparent conductive materials or manufacturing processes are required.

Thus, more recently, US patent US20070001186 describes p-type In x Al y Ga 1-xy N (0≤x, 0≤y, x + y) in a wafer bonding process of a thick transparent electroconductive material wafer including ZnO. ≤1) A technique in which an ohmic contact current spreading layer 50 is formed by grafting on an upper portion of a semiconductor has been designed. However, the transparent electroconductive material system existing in the form of such a thick wafer is not easy to make excellent electrical conductivity of 10 ^-3 Ωcm or less, and the wafer bonding is difficult due to the difference of thermal expansion coefficient. It is difficult and expensive to manufacture, making it unsuitable for practical purposes.

Therefore, in the art, while maintaining high light transparency, p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y, which is the uppermost layer of the upper nitride-based cladding layer 40) There is a need for a high quality group III-nitride semiconductor light emitting diode device having an ohmic contact current spreading layer 50 which forms a good ohmic contact interface with ≤1) and a manufacturing method thereof.

In addition, the energy conversion efficiency (lm / W) of the packaged light emitting diode device should be increased by drawing out the light generated in the nitride active layer in the light emitting structure for the group III nitride semiconductor light emitting diode device to the outside as much as possible. In general, the external luminous efficiency of group III-nitride semiconductor light emitting diodes is surprisingly low. This is because the large refractive index difference between the ohmic contact current spreading layer and the molding material, such as group III-nitride semiconductor or GaN, or ITO, does not emit much of the light generated in the LED structure to the outside. It will go back to the inside of LED and disappear. For example, assuming that the refractive index of gallium nitride (GaN) is about 2.3 and the refractive index of the molding material is about 1.5, the amount of light totally reflected at the joint surface of the two materials is about 90%. To solve this problem, p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y, which is the uppermost layer of the upper nitride cladding layer of the light emitting structure for group III-nitride semiconductor light emitting diode device) ≤1) or surface irregularities or patterning of various shapes and dimensions using an etching process on the surface of the ohmic contact current spreading layer. In this case, it was confirmed that the light extraction efficiency is significantly improved.

However, the step of introducing surface irregularities or patterning on the surface of the p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) or ohmic contact current spreading layer as the top layer. At the same time, the additional layer of p-type In x Al y Ga 1-xy N (0≤x, 0≤y, x + y≤1) or ohmic contact current is complicated by requiring additional photolitho and etching processes. Electrically adversely affects the surface of the spreading layer to increase the driving voltage and leakage current of the LED device to impair the energy conversion efficiency.

In order to improve the overall performance of group III-nitride-based semiconductor light emitting diode devices, the present invention provides a combination of wafer bonding, growth substrate separation, and surface irregularities of a growth substrate on which a patterned support substrate and a light emitting structure for a light emitting diode device are formed. By manufacturing a light emitting diode device, it was intended to increase the light extraction efficiency by minimizing the total amount of light generated in the active layer of the device is totally reflected inside.

The present invention provides a patterned supporting substrate using a wafer bonding process to change the incident angle of light generated in the active layer in the group III nitride-based semiconductor LED device to improve light extraction efficiency. A light emitting diode device including a light emitting structure for a light emitting diode device in which a p-type conductive upper nitride cladding layer, a nitride active layer made of another semiconductor, and an n-type conductive lower nitride cladding layer are sequentially stacked on an upper surface thereof; to provide.

On the other hand, in order to improve the light extraction efficiency by changing the angle of incidence of light generated in the active layer in the group III-nitride semiconductor light emitting diode device, in addition to the patterned supporting substrate, the n-type light emitting surface Provided is a group III nitride semiconductor light emitting diode device characterized by having a surface texture on the upper surface of a conductive lower nitride based cladding layer.

The present invention provides a light emitting device using a group III nitride-based semiconductor represented by the formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) as a structural means for achieving the above object. In the method of manufacturing a diode (hereinafter, group 3 nitride-based semiconductor light emitting diode) device,

Preparing a growth substrate for growing a light emitting structure for a light emitting diode device; A light emitting diode device having a lower nitride cladding layer made of an n-type conductive semiconductor, a nitride active layer made of another semiconductor, and an upper nitride cladding layer made of a p-type semiconductor Forming a structure; Forming a transparent ohmic contact current spreading layer on an upper surface of the nitride based cladding layer of the light emitting structure for the light emitting diode device; Forming a wafer bonding layer on an upper surface of the transparent ohmic contact current spreading layer; Preparing a patterned supporting substrate; Forming a planarization layer on an upper surface of the patterned support substrate; Forming a wafer bonding layer on an upper surface of the planarization layer formed on the patterned support substrate; Contacting the two wafer bonding layers to wafer bond the growth substrate and the support substrate to form a composite; Separating and removing a growth substrate from the wafer-bonded composite; Removing a portion of the light emitting structure for the light emitting diode device, exposing the transparent ohmic contact current spreading layer to air, and forming a p-type ohmic contact electrode and an electrode pad on an upper surface of the transparent ohmic contact current spreading layer; step; And forming a partial n-type electrode structure on a portion of the upper surface of the lower nitride-based cladding layer.

The present invention provides a group III nitride-based semiconductor represented by the chemical formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1) as another means for achieving the above object. In the light emitting diode (hereinafter referred to as group III nitride semiconductor light emitting diode) device manufacturing method,

Preparing a growth substrate for growing a light emitting structure for a light emitting diode device; A light emitting diode device having a lower nitride cladding layer made of an n-type conductive semiconductor, a nitride active layer made of another semiconductor, and an upper nitride cladding layer made of a p-type semiconductor Forming a structure; Forming a transparent ohmic contact current spreading layer on an upper surface of the nitride based cladding layer of the light emitting structure for the light emitting diode device; Forming a wafer bonding layer on an upper surface of the transparent ohmic contact current spreading layer; Preparing a patterned supporting substrate; Forming a planarization layer on an upper surface of the patterned support substrate; Forming a wafer bonding layer on an upper surface of the planarization layer formed on the patterned support substrate; Contacting the two wafer bonding layers to wafer bond the growth substrate and the support substrate to form a composite; Separating and removing a growth substrate from the wafer-bonded composite; Removing a portion of the light emitting structure for the light emitting diode device, exposing the transparent ohmic contact current spreading layer to air, and forming a p-type ohmic contact electrode and an electrode pad on an upper surface of the transparent ohmic contact current spreading layer; step; And forming a front n-type electrode structure on the entire upper surface of the lower nitride-based cladding layer.

An n-type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN having a thickness of 5 nanometers (nm) or less conventionally known on the upper surface of the p-type conductive upper nitride-based cladding layer of the light emitting diode device , SiC, SiCN, MgN, ZnN monolayers, p-type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN monolayers with thicknesses of 5 nanometers (nm) or less, or other dopants and compositions ( It is desirable to form a superlattice composed of nitride or carbon nitride of group 2, 3, or 4 elements having a composition.

The transparent ohmic contacting current spreading layer has a high light transmittance characteristic of 70% or more in the wavelength range of 600 nanometers (nm) or less, and simultaneously with the upper nitride-based cladding layer. Preferred are materials that form an ohmic contacting interface.

The transparent ohmic contact current spreading layer may include a separate thin film layer which may serve to prevent diffusion of a material, improve bonding and bonding between materials, or prevent oxidation of a material.

The patterned supporting substrate is preferably a material having a thermal expansion coefficient difference of 2 ppm or less in a growth substrate for growing a light emitting structure for a light emitting diode device.

The patterned supporting substrate is formed by introducing a wet or dry etching process of an irregular pattern having a predetermined shape and dimensions on the upper surface of the supporting substrate. do. Furthermore, it is desirable to form a predetermined shape and dimension with a regular pattern.

It is preferable that the leveling layer grows transparent materials using MOCVD, HVPE, and MBE equipment, or deposits transparent materials using sputter, evaporator, PLD, and spin-coater equipment. .

Prior to forming the composite through wafer bonding, the light emitting structure for the light emitting diode device, the transparent ohmic contact spreading layer, and the wafer bonding layer formed on the upper surface of the growth substrate may have a predetermined shape and dimensions. It is desirable to perform an isolation process until the growth substrate is exposed to the atmosphere.

The wafer bonding is preferably performed at a temperature of from room temperature to 700 ° C. and various gas atmospheres such as oxygen, nitrogen, argon, or vacuum. .

The wafer bonding may be made of any material that forms a strong mechanical and thermally stable bonding force between the transparent ohmic contact current spreading layer and the patterned support substrate, but may emit as much light generated inside the light emitting diode device as possible. It is desirable to preferentially select transparent materials such as SiO 2, SiN x, Al 2 O 3, ZnO, ZnS, MgF 2, spin on glass (SOG).

The growth substrate separation (lift-off) is chemical-mechanical polishing (CMP), laser lift-off (LLO) using a photon beam of a specific wavelength band, or using a wet etching solution Chemical lift-off (CLO) and the like are preferred.

The partial n-type electrode structure (partial n -type electrode system) is more than 50% reflectivity at the lower nitride-based cladding layer and the upper surface of a partial area having a predetermined shape and dimensions of 600 nanometers (nm) wavelength range of less than It comprises a reflective ohmic contact electrode and electrode pad which have.

The front n-type electrode structure (full n -type electrode system) is transparent with the lower nitride-based cladding layer region and the ohmic total upper surface to form a contact interface, and 600 nanometers (nm) of 70% or more transmittance in the wavelength range of less than An ohmic contact electrode and a portion of the upper surface of the transparent ohmic contact electrode are formed, and a reflective electrode pad having a reflectance of 50% or more in a wavelength band of 600 nm or less is formed.

As described above, the present invention is a group III nitride-based semiconductor light emitting device (light emitting diode) device, the surface irregularities having a predetermined shape and dimensions on the light emitting surface of the light emitting structure for a light emitting diode device on the patterned support substrate In addition to the good electrical characteristics of the entire LED device by forming a good, there is an excellent effect to minimize the total reflection of the light generated inside the light emitting diode device to improve the brightness of the light emitting diode device.

Hereinafter, with reference to the accompanying drawings, it will be described in more detail with respect to the Group III nitride semiconductor light emitting diode device manufactured according to the present invention.

1 is a cross-sectional view of a group III-nitride semiconductor light emitting diode device shown as a first embodiment manufactured by the present invention.

Referring to Figure 1, the light emitting diode device according to an embodiment of the present invention on the upper surface of the patterned support substrate 101, the planarization layer 102, two wafer bonding layers (103, 207), transparent ohmic contact current The upper nitride-based cladding layer 205 made of the spedding layer 206, the p-type conductive semiconductor, the nitride-based active layer 204, the lower nitride-based cladding layer 203 made of the n-type conductive semiconductor, and the partial n-type electrode The structure 301, a p-type ohmic contact electrode and an electrode pad 302, and a back reflector 303 are included. In this case, surface irregularities are not introduced to the upper surface of the lower nitride based cladding layer 203.

The patterned support substrate 101 may be formed by introducing a wet or dry etching process to a regular or irregular pattern having a predetermined shape and dimensions. At this time, the patterned support substrate 101 is any one selected from the group consisting of aluminum nitride (AlN), gallium nitride (GaN), single crystal sapphire (epitaxial sapphire), polycrystalline sapphire, or silicon carbide (SiC). Formed.

The planarization layer 102 is formed directly on the patterned support substrate 101, and grows transparent materials using MOCVD, HVPE, and MBE equipment, or sputter, evaporator, PLD, and spin-coater equipment. It is possible to deposit a transparent material using (deposition). In this case, the planarization layer 102 is formed of any one selected from the group consisting of GaN, AlGaN, ZnO, SiO 2, SiN x, SOG, and Al 2 O 3.

The two wafer bonding layers 103 and 207 may be any materials that form a mechanical and thermally stable bonding force between the transparent ohmic contact current spreading layer and the patterned support substrate, but light generated inside the light emitting diode device may be used. It is preferable to preferentially select transparent materials such as SiO 2, SiN x, Al 2 O 3, ZnO, ZnS, MgF 2, and spin on glass (SOG), which can emit as much as possible to the outside.

The two wafer bonding layers 103 and 207 are bonded by a strong wafer bonding force between the two layers.

The transparent ohmic contact current spreading layer 206 may have a wavelength region of 600 nm or less, such as oxidized nickel gold (Ni-Au-O), indium tin oxide (ITO), or zinc oxide (ZnO). It has a high light transmittance characteristic of 70% or more in the band and can be formed by a physical vapor deposition (PVD) or chemical vapor deposition (CVD) method.

The upper nitride-based cladding layer 205 of the p-type conductivity is a region in which a portion of the transparent ohmic contact current spreading layer 206 is provided to provide holes, wherein the upper nitride of the p-type conductivity is present. The cladding layer 205 may form a single layer or a multilayer structure formed of p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1).

The upper nitride-based cladding layer 205 of the p-type conductivity may be formed by doping magnesium (Mg) or zinc (Zn).

The nitride-based light emitting layer 204 is located on the upper surface of the p-type conductive nitride layer 205 and is a region where electrons and holes are recombined and include InGaN, AlGaN, GaN, and AlInGaN. It is done by The emission wavelength of light emitted from the light emitting diode device is determined according to the type of material constituting the nitride-based light emitting layer 204. The nitride-based light emitting layer 204 may be a multilayer film in which quantum well layers and barrier layers are repeatedly formed. The barrier layer and the well layer may be a binary, ternary, or quaternary compound nitride-based semiconductor layer represented by the general formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). Can be. Furthermore, the barrier layer and the well layer may be formed by doping silicon (Si), magnesium (Mg), zinc (Zn), or the like.

The lower nitride-based cladding layer 203 of the n-type conductivity is positioned on an upper surface of the nitride-based light emitting layer 204 to provide electrons. In this case, the lower nitride-based cladding layer 203 of the n-type conductivity is provided. May form a single layer or multilayer structure formed of n-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1).

The upper nitride-based cladding layer 203 of the n-type conductivity may be formed by doping silicon (Si).

On the other hand, the p-type conductive upper nitride-based cladding layer 205 and the transparent ohmic contact current spreading layer 206 of the light emitting structure for the light emitting diode device has a thickness of 5 nm or less conventionally known. N type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN, SiC, SiCN, MgN, ZnN single layer, p type conductive InGaN, GaN, AlInN, AlN , Superlattice consisting of nitride or carbon nitride of Group 2, 3, or 4 elements having InN, AlGaN, AlInGaN monolayers or other dopant and composition elements It can intervene in a superlattice.

The p-type ohmic contact electrode and the electrode pad 302 are disposed on an upper surface of the transparent ohmic contact current spreading layer 206 exposed to the atmosphere. The p-type ohmic contact electrode and the electrode pad 302 are made of a material forming an ohmic contact interface with the transparent ohmic contact current spreading layer 206, for example, a metal such as Pt / Au, and lift-off. off) method.

The partial n-type electrode structure 301 is formed on the exposed surface of the lower nitride-based cladding layer 203 of n-type conductivity without surface irregularities, and may be formed using a lift-off method. The partial n-type electrode structure 301 has a predetermined shape and dimension in a portion of the upper surface of the lower nitride-based cladding layer 203 and has a reflectivity of 50% or more in a wavelength band of 600 nanometers (nm) or less. It consists of an ohmic contact electrode and an electrode pad.

The back reflector 303 is located on the back-side of the patterned support substrate and serves to redirect the light emitted from the light emitting diode device in the opposite direction. At this time, the back reflector 303 is preferably a material having a reflectivity of 70% or more in the wavelength band of 600 nanometers (nm) or less, for example, aluminum (Al), silver (Ag), rhodium (Rh), chromium It is formed of any one selected from the group consisting of (Cr), nickel (Ni), and gold (Au).

2 is a cross-sectional view of a group III-nitride semiconductor light emitting diode device shown as a second embodiment produced by the present invention.

Referring to Figure 2, the light emitting diode device according to an embodiment of the present invention on the upper surface of the patterned support substrate 101, the planarization layer 102, two wafer bonding layers (103, 207), transparent ohmic contact current The upper nitride-based cladding layer 205 made of the spedding layer 206, the p-type conductive semiconductor, the nitride-based active layer 204, the lower nitride-based cladding layer 203 made of the n-type conductive semiconductor, and the front n-type electrode The structures 304 and 301, a p-type ohmic contact electrode and an electrode pad 302, and a back reflector 303 are included. In this case, surface irregularities are introduced to the upper surface of the lower nitride-based cladding layer 203.

The patterned support substrate 101 may be formed by introducing a wet or dry etching process to a regular or irregular pattern having a predetermined shape and dimensions. At this time, the patterned support substrate 101 is any one selected from the group consisting of aluminum nitride (AlN), gallium nitride (GaN), single crystal sapphire (epitaxial sapphire), polycrystalline sapphire, or silicon carbide (SiC). Formed.

The planarization layer 102 is formed directly on the patterned support substrate 101, and grows transparent materials using MOCVD, HVPE, and MBE equipment, or sputter, evaporator, PLD, and spin-coater equipment. It is possible to deposit a transparent material using (deposition). In this case, the planarization layer 102 is formed of any one selected from the group consisting of GaN, AlGaN, ZnO, SiO 2, SiN x, SOG, and Al 2 O 3.

The two wafer bonding layers 103 and 207 can be made of any material that forms a mechanically and thermally stable bonding force between the transparent ohmic contact current spreading layer and the patterned support substrate, but is formed inside the light emitting diode device. It is preferable to first select transparent materials such as SiO 2, SiN x, Al 2 O 3, ZnO, ZnS, MgF 2, and spin on glass (SOG), which can emit as much light as possible to the outside.

The two wafer bonding layers 103 and 207 are bonded by a strong wafer bonding force between the two layers.

The transparent ohmic contact current spreading layer 206 may have a wavelength region of 600 nm or less, such as oxidized nickel gold (Ni-Au-O), indium tin oxide (ITO), or zinc oxide (ZnO). It has a high light transmittance characteristic of 70% or more in the band and can be formed by a physical vapor deposition (PVD) or chemical vapor deposition (CVD) method.

The upper nitride-based cladding layer 205 of the p-type conductivity is a region in which a portion of the transparent ohmic contact current spreading layer 206 is provided to provide holes, wherein the upper nitride of the p-type conductivity is present. The cladding layer 205 may form a single layer or a multilayer structure formed of p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1).

The upper nitride-based cladding layer 205 of the p-type conductivity may be formed by doping magnesium (Mg) or zinc (Zn).

The nitride-based light emitting layer 204 is located on the upper surface of the p-type conductive nitride layer 205 and is a region where electrons and holes are recombined and include InGaN, AlGaN, GaN, and AlInGaN. It is done by The emission wavelength of light emitted from the light emitting diode device is determined according to the type of material constituting the nitride-based light emitting layer 204. The nitride-based light emitting layer 204 may be a multilayer film in which quantum well layers and barrier layers are repeatedly formed. The barrier layer and the well layer may be a binary, ternary, or quaternary compound nitride-based semiconductor layer represented by the general formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). Can be. Furthermore, the barrier layer and the well layer may be formed by doping silicon (Si), magnesium (Mg), zinc (Zn), or the like.

The lower nitride-based cladding layer 203 of the n-type conductivity is positioned on an upper surface of the nitride-based light emitting layer 204 to provide electrons. In this case, the lower nitride-based cladding layer 203 of the n-type conductivity is provided. May form a single layer or multilayer structure formed of n-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1).

The upper nitride-based cladding layer 203 of the n-type conductivity may be formed by doping silicon (Si).

On the other hand, the p-type conductive upper nitride-based cladding layer 205 and the transparent ohmic contact current spreading layer 206 of the light emitting structure for the light emitting diode device has a thickness of 5 nm or less conventionally known. N type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN, SiC, SiCN, MgN, ZnN single layer, p type conductive InGaN, GaN, AlInN, AlN , Superlattice consisting of nitride or carbon nitride of Group 2, 3, or 4 elements having InN, AlGaN, AlInGaN monolayers or other dopant and composition elements It can interpose superlattices.

The p-type ohmic contact electrode and the electrode pad 302 are positioned on an upper surface of the transparent ohmic contact current spreading layer 206 exposed to the atmosphere. The p-type ohmic contact electrode and the electrode pad 302 are made of a material forming an ohmic contact interface with the transparent ohmic contact current spreading layer 206, for example, a metal such as Pt / Au, and lift-off. off) method.

The partial n-type electrode structure 301 is formed on the exposed surface of the lower nitride-based cladding layer 203 of the n-type conductivity having the surface irregularities 304 formed thereon, and may be formed using a lift-off method. The partial n-type electrode structure 301 has a predetermined shape and dimensions in a portion of the upper surface of the lower nitride-based cladding layer 203 on which the surface irregularities 304 are formed, and has a wavelength of less than 600 nanometers (nm). Consists of a reflective ohmic contact electrode and an electrode pad having a reflectance of 50% or more.

The back reflector 303 is located on the back-side of the patterned support substrate and serves to redirect the light emitted from the light emitting diode device in the opposite direction. At this time, the back reflector 303 is preferably a material having a reflectivity of 70% or more in the wavelength band of 600 nanometers (nm) or less, for example, aluminum (Al), silver (Ag), rhodium (Rh), chromium It is formed of any one selected from the group consisting of (Cr), nickel (Ni), and gold (Au).

3 is a cross-sectional view of a group III-nitride semiconductor light emitting diode device shown as a third embodiment of the present invention.

Referring to Figure 3, the light emitting diode device according to an embodiment of the present invention on the upper surface of the patterned support substrate 101, the planarization layer 102, two wafer bonding layers (103, 207), transparent ohmic contact current The upper nitride-based cladding layer 205 made of the spedding layer 206, the p-type conductive semiconductor, the nitride-based active layer 204, the lower nitride-based cladding layer 203 made of the n-type conductive semiconductor, and the front n-type electrode The structures 305 and 301, the p-type ohmic contact electrode and the electrode pad 302, and the back reflector 303 are included. In this case, surface irregularities are not introduced to the upper surface of the lower nitride based cladding layer 203.

The patterned support substrate 101 may be formed by introducing a wet or dry etching process to a regular or irregular pattern having a predetermined shape and dimensions. At this time, the patterned support substrate 101 is any one selected from the group consisting of aluminum nitride (AlN), gallium nitride (GaN), single crystal sapphire (epitaxial sapphire), polycrystalline sapphire, or silicon carbide (SiC). Formed.

The planarization layer 102 is formed directly on the patterned support substrate 101, and grows transparent materials using MOCVD, HVPE, and MBE equipment, or sputter, evaporator, PLD, and spin-coater equipment. It is possible to deposit a transparent material using (deposition). In this case, the planarization layer 102 is formed of any one selected from the group consisting of GaN, AlGaN, ZnO, SiO 2, SiN x, SOG, and Al 2 O 3.

The two wafer bonding layers 103 and 207 may be any materials that form a mechanical and thermally stable bonding force between the transparent ohmic contact current spreading layer and the patterned support substrate, but light generated inside the light emitting diode device may be used. It is preferable to preferentially select transparent materials such as SiO 2, SiN x, Al 2 O 3, ZnO, ZnS, MgF 2, and spin on glass (SOG), which can emit as much as possible to the outside.

The two wafer bonding layers 103 and 207 are bonded by a strong wafer bonding force between the two layers.

The transparent ohmic contact current spreading layer 206 may have a wavelength region of 600 nm or less, such as oxidized nickel gold (Ni-Au-O), indium tin oxide (ITO), or zinc oxide (ZnO). It has a high light transmittance characteristic of 70% or more in the band and can be formed by a physical vapor deposition (PVD) or chemical vapor deposition (CVD) method.

The upper nitride-based cladding layer 205 of the p-type conductivity is a region in which a portion of the transparent ohmic contact current spreading layer 206 is provided to provide holes, wherein the upper nitride of the p-type conductivity is present. The cladding layer 205 may form a single layer or a multilayer structure formed of p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1).

The upper nitride-based cladding layer 205 of the p-type conductivity may be formed by doping magnesium (Mg) or zinc (Zn).

The nitride-based light emitting layer 204 is located on the upper surface of the p-type conductive nitride layer 205 and is a region where electrons and holes are recombined and include InGaN, AlGaN, GaN, and AlInGaN. It is done by The emission wavelength of light emitted from the light emitting diode device is determined according to the type of material constituting the nitride-based light emitting layer 204. The nitride-based light emitting layer 204 may be a multilayer film in which quantum well layers and barrier layers are repeatedly formed. The barrier layer and the well layer are binary, ternary, or quaternary compound nitride-based semiconductor layers represented by general formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). Can be. Furthermore, the barrier layer and the well layer may be formed by doping silicon (Si), magnesium (Mg), zinc (Zn), or the like.

The lower nitride-based cladding layer 203 of the n-type conductivity is positioned on an upper surface of the nitride-based light emitting layer 204 to provide electrons. In this case, the lower nitride-based cladding layer 203 of the n-type conductivity is provided. May form a single layer or multilayer structure formed of n-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1).

The upper nitride-based cladding layer 203 of the n-type conductivity may be formed by doping silicon (Si).

On the other hand, the p-type conductive upper nitride-based cladding layer 205 and the transparent ohmic contact current spreading layer 206 of the light emitting structure for the light emitting diode device has a thickness of 5 nm or less conventionally known. N type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN, SiC, SiCN, MgN, ZnN single layer, p type conductive InGaN, GaN, AlInN, AlN , Superlattice consisting of nitride or carbon nitride of Group 2, 3, or 4 elements having InN, AlGaN, AlInGaN monolayers or other dopant and composition elements It can interpose superlattices.

The p-type ohmic contact electrode and the electrode pad 302 are disposed on an upper surface of the transparent ohmic contact current spreading layer 206 exposed to the atmosphere. The p-type ohmic contact electrode and the electrode pad 302 are made of a material forming an ohmic contact interface with the transparent ohmic contact current spreading layer 206, for example, a metal such as Pt / Au, and lift-off. off) method.

The front n-type electrode structures 305 and 301 are formed on the exposed surface of the lower nitride-based cladding layer 203 of n-type conductivity having no surface irregularities, and may be formed using a lift-off method. The front n-type electrode structures 305 and 301 form an ohmic contact interface with the entire region of the upper surface of the lower nitride-based cladding layer 203 where surface irregularities are not formed, and are 70 in a wavelength band of 600 nm or less. It is formed of a transparent ohmic contact electrode 305 having a transmittance of about% or more and a reflective electrode pad 301 having a reflectance of 50% or more in a wavelength band of 600 nanometers (nm) or less and formed in a portion of the upper surface of the transparent ohmic contact electrode. do.

The back reflector 303 is located on the back-side of the patterned support substrate and serves to redirect the light emitted from the light emitting diode device in the opposite direction. At this time, the back reflector 303 is preferably a material having a reflectivity of 70% or more in the wavelength band of 600 nanometers (nm) or less, for example, aluminum (Al), silver (Ag), rhodium (Rh), chromium It is formed of any one selected from the group consisting of (Cr), nickel (Ni), and gold (Au).

4 is a cross-sectional view of a group III-nitride semiconductor light emitting diode device shown as a fourth embodiment manufactured by the present invention.

Referring to Figure 4, the light emitting diode device according to an embodiment of the present invention on the patterned support substrate 101, the planarization layer 102, two wafer bonding layers (103, 207), transparent ohmic contact current The upper nitride-based cladding layer 205 made of the spedding layer 206, the p-type conductive semiconductor, the nitride-based active layer 204, the lower nitride-based cladding layer 203 made of the n-type conductive semiconductor, and the front n-type electrode The structures 304 and 301, a p-type ohmic contact electrode and an electrode pad 302, and a back reflector 303 are included. In this case, surface irregularities are introduced to the upper surface of the lower nitride-based cladding layer 203.

The patterned support substrate 101 may be formed by introducing a wet or dry etching process to a regular or irregular pattern having a predetermined shape and dimensions. At this time, the patterned support substrate 101 is any one selected from the group consisting of aluminum nitride (AlN), gallium nitride (GaN), single crystal sapphire (epitaxial sapphire), polycrystalline sapphire, or silicon carbide (SiC). Formed.

The planarization layer 102 is formed directly on the patterned support substrate 101, and grows transparent materials using MOCVD, HVPE, and MBE equipment, or sputter, evaporator, PLD, and spin-coater equipment. It is possible to deposit a transparent material using (deposition). In this case, the planarization layer 102 is formed of any one selected from the group consisting of GaN, AlGaN, ZnO, SiO 2, SiN x, SOG, and Al 2 O 3.

The two wafer bonding layers 103 and 207 may be any materials that form a mechanical and thermally stable bonding force between the transparent ohmic contact current spreading layer and the patterned support substrate, but light generated inside the light emitting diode device may be used. It is preferable to preferentially select transparent materials such as SiO 2, SiN x, Al 2 O 3, ZnO, ZnS, MgF 2, and spin on glass (SOG), which can emit as much as possible to the outside.

The two wafer bonding layers 103 and 207 are bonded by a strong wafer bonding force between the two layers.

The transparent ohmic contact current spreading layer 206 may have a wavelength region of 600 nm or less, such as oxidized nickel gold (Ni-Au-O), indium tin oxide (ITO), or zinc oxide (ZnO). It has a high light transmittance characteristic of 70% or more in the band and can be formed by a physical vapor deposition (PVD) or chemical vapor deposition (CVD) method.

The upper nitride-based cladding layer 205 of the p-type conductivity is a region in which a portion of the transparent ohmic contact current spreading layer 206 is provided to provide holes, wherein the upper nitride of the p-type conductivity is present. The cladding layer 205 may form a single layer or a multilayer structure formed of p-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1).

The upper nitride-based cladding layer 205 of the p-type conductivity may be formed by doping magnesium (Mg) or zinc (Zn).

The nitride-based light emitting layer 204 is located on the upper surface of the p-type conductive nitride layer 205 and is a region where electrons and holes are recombined and include InGaN, AlGaN, GaN, and AlInGaN. It is done by The emission wavelength of light emitted from the light emitting diode device is determined according to the type of material constituting the nitride-based light emitting layer 204. The nitride-based light emitting layer 204 may be a multilayer film in which quantum well layers and barrier layers are repeatedly formed. The barrier layer and the well layer are binary, ternary, or quaternary compound nitride-based semiconductor layers represented by general formula In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1). Can be. Furthermore, the barrier layer and the well layer may be formed by doping silicon (Si), magnesium (Mg), zinc (Zn), or the like.

The lower nitride-based cladding layer 203 of the n-type conductivity is positioned on an upper surface of the nitride-based light emitting layer 204 to provide electrons. In this case, the lower nitride-based cladding layer 203 of the n-type conductivity is provided. May form a single layer or multilayer structure formed of n-type In x Al y Ga 1-xy N (0 ≦ x, 0 ≦ y, x + y ≦ 1).

The upper nitride-based cladding layer 203 of the n-type conductivity may be formed by doping silicon (Si).

On the other hand, the p-type conductive upper nitride-based cladding layer 205 and the transparent ohmic contact current spreading layer 206 of the light emitting structure for the light emitting diode device has a thickness of 5 nm or less conventionally known. N-type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN, SiC, SiCN, MgN, ZnN single layer, p-type InGaN, GaN, AlInN, AlN having a thickness of 5 nanometers (nm or less) , Superlattice consisting of nitride or carbon nitride of Group 2, 3, or 4 elements having InN, AlGaN, AlInGaN monolayers or other dopant and composition elements It can interpose superlattices.

The p-type ohmic contact electrode and the electrode pad 302 are disposed on an upper surface of the transparent ohmic contact current spreading layer 206 exposed to the atmosphere. The p-type ohmic contact electrode and the electrode pad 302 are made of a material forming an ohmic contact interface with the transparent ohmic contact current spreading layer 206, for example, a metal such as Pt / Au, and lift-off. off) method.

The front n-type electrode structures 305 and 301 are formed on the exposed surface of the lower nitride-based cladding layer 203 of the n-type conductivity having the surface irregularities 304 formed thereon and may be formed using a lift-off method. The front n-type electrode structures 305 and 301 form an ohmic contact interface with the entire region of the upper surface of the lower nitride based cladding layer 203 on which the surface irregularities 304 are formed, and have a wavelength band of 600 nm or less. A transparent ohmic contact electrode 305 having a transmittance of 70% or more and a reflective electrode pad 301 having a reflectance of 50% or more in a wavelength band of 600 nanometers (nm) or less and formed in a portion of the upper surface of the transparent ohmic contact electrode. Configure.

The back reflector 303 is located on the back-side of the patterned support substrate and serves to redirect the light emitted from the light emitting diode device in the opposite direction. At this time, the back reflector 303 is preferably a material having a reflectivity of 70% or more in the wavelength band of 600 nanometers (nm) or less, for example, aluminum (Al), silver (Ag), rhodium (Rh), chromium It is formed of any one selected from the group consisting of (Cr), nickel (Ni), and gold (Au).

5 to 17 illustrate one embodiment of the group III-nitride semiconductor LED device in detail.

5 is a cross-sectional view in which a planarization layer is formed on an upper surface of a patterned support substrate.

As shown, a regular or irregular pattern having a predetermined shape and dimension is formed on the upper surface of the supporting substrate 101 by introducing a wet or dry etching process. At this time, the patterned support substrate 101 is any one selected from the group consisting of aluminum nitride (AlN), gallium nitride (GaN), single crystal sapphire (epitaxial sapphire), polycrystalline sapphire, or silicon carbide (SiC). Formed.

The leveling layer 102 disposed on the patterned support substrate 101 is grown on a transparent material using MOCVD, HVPE, or MBE equipment, or by using a sputter, evaporator, PLD, or spin-coater equipment. To form a transparent material by deposition. In this case, the planarization layer 102 is formed of any one selected from the group consisting of GaN, AlGaN, ZnO, SiO 2, SiN x, SOG, and Al 2 O 3.

6 is a cross-sectional view illustrating a light emitting structure for a group III nitride-based light emitting diode device grown on an upper surface of a growth substrate and a transparent ohmic contact current spreading layer formed on the light emitting structure for a light emitting diode device.

As shown in FIG. 6A, a buffer layer 202 for reducing stress through lattice matching with a growth substrate on a growth substrate 201 of sapphire, SiC, GaN, AlN, etc. A light emitting structure for a light emitting diode device comprising a cladding layer 203, a nitride based active layer 204, and a p-type conductive upper nitride based cladding layer 205 is formed.

The light emitting structure for the light emitting diode device may be formed by continuously forming a GaN layer, an InGaN layer, an AlInN layer, an AlGaN layer, or an AlInGaN layer, and may be formed by a MOCVD or MBE process. Furthermore, n-type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN, SiC having a thickness of 5 nanometers (nm) or less conventionally known on the upper surface of the p-type conductive upper nitride-based cladding layer 205. , SiCN, MgN, ZnN monolayers, p-type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN monolayers with thicknesses less than 5 nanometers (nm) or other dopants and compositions It is also possible to form a superlattice composed of nitrides or carbon nitrides of group 2, 3, or 4 elements having an element.

As shown in FIG. 6B, a transparent ohmic contact current spreading layer 206 is formed on an upper surface of the upper nitride based cladding layer 205 of the light emitting diode light emitting structure. The transparent ohmic contact current spreading layer 206 to complement the upper nitride based cladding layer having low electrical conductivity due to the low hole carrier concentration is 70% or more in the wavelength region of 600 nanometers (nm) or less. Physical vapor deposition of materials such as oxidized nickel-gold (Ni-Au-O), indium tin oxide (ITO), zinc oxide (ZnO), etc., which have high light transmittance characteristics, is performed in a temperature range of PVD) or chemical vapor deposition (CVD) methods.

Furthermore, after the transparent ohmic contact current spreading layer 206 is deposited, additional annealing may be performed to improve electrical and optical properties.

FIG. 7 is a cross-sectional view of a wafer bonding layer formed on the planarization layer on the patterned support substrate and the upper surface of the transparent ohmic contact spreading layer on the growth substrate.

As shown in Fig. 7A, a wafer bonding layer 103 is formed on the top surface of the planarization layer on the patterned support substrate. As shown in FIG. 7B, the wafer bonding layer 207 is formed on the upper surface of the transparent ohmic contact spreading layer 206 on the growth substrate.

The two wafer bonding layers 103 and 207 may be any materials that form mechanically and thermally stable bonding forces, but SiO 2, SiN x, Al 2 O 3, and the like may emit as much light as possible from the inside of the light emitting diode device to the outside. It is preferable to preferentially select transparent materials such as ZnO, ZnS, MgF 2, spin on glass (SOG).

In addition, the wafer bonding layer 103 on the top surface of the planarization layer and the wafer bonding layer 207 on the top surface of the transparent ohmic contact current spreading layer 206 may be formed of the same or different materials.

8 is a cross-sectional view of a composite wafer bonded to a growth substrate having a support substrate patterned by bonding two wafer bonding layers and a light emitting structure for a light emitting diode device.

As shown, the wafer bonding layer 103 formed on the top surface of the planarization layer 102 of the patterned support substrate 101 and the transparent ohmic contact current spreading layer 206 of the growth substrate 201 are formed. 207 is bonded to strongly bond the wafers to form a composite (C).

The wafer bonding is preferably performed at a temperature of from room temperature to 700 ° C. and various gas atmospheres such as oxygen, nitrogen, argon, or vacuum.

In particular, the interfacial property between the upper nitride-based cladding layer 205 and the transparent ohmic contact current spreading layer 206 of the light emitting diode device light emitting structure is not degraded when the composite C is formed through wafer bonding. Should be.

9 is a cross-sectional view of a growth substrate for growing a light emitting structure for a light emitting diode device from a wafer-bonded composite.

As shown, the growth substrate 201 is lifted off from the wafer-bonded composite (C). In the method of separating the growth substrate 201 from the complex, a photon-beam having a specific wavelength is irradiated to the back-side of the transparent growth substrate 201 to form a buffer layer. By using a thermo-chemical decomposition reaction or using a specific etching solution (etching solution) (chemical etching reaction).

In particular, after the growth substrate 201 is separated from the composite, it is preferable to completely remove the residues of the buffer layer 202 remaining on the upper surface of the lower nitride-based cladding layer 203.

FIG. 10 is a cross-sectional view of a transparent ohmic contact current spreading layer exposed to the atmosphere by removing a portion of the light emitting structure for a light emitting diode device from the composite in which the growth substrate is removed.

As shown in the drawing, a portion of the light emitting structure 203, 204, 205 for the light emitting diode device is removed in order to apply a current from the outside, and the transparent ohmic contact current spreading layer 206 is exposed to the atmosphere.

As a method for removing a portion of the light emitting structure for the light emitting diode device 203, 204, 205 using a conventionally known dry etching (wet etching) or wet etching (wet etching). In particular, it is further preferable to use a base, salt, or acid solution including KOH.

FIG. 11 is a cross-sectional view of an n-type electrode structure, a p-type ohmic contact electrode, and an electrode pad formed on an upper surface of a lower nitride-based cladding layer having no surface irregularities and an upper surface of a transparent ohmic contact current spreading layer, respectively.

As illustrated, a partial n-type electrode structure 301 is formed in a portion of the upper surface of the lower nitride-based cladding layer 203 exposed to the atmosphere, and at the same time, p is disposed on the upper surface of the transparent ohmic contact current spreading layer 206. The type ohmic contact electrode and the electrode pad 302 are formed.

The partial n-type electrode structure 301 is formed on the exposed surface of the lower nitride-based cladding layer 203 of n-type conductivity without surface irregularities, and may be formed using a lift-off method. The partial n-type electrode structure 301 has a predetermined shape and dimension in a portion of the upper surface of the lower nitride-based cladding layer 203 on which surface irregularities are not formed, and is 50 in a wavelength band of 600 nm or less. The reflective ohmic contact electrode and the electrode pad which have a reflectance of% or more are comprised.

The p-type ohmic contact electrode and the electrode pad 302 are disposed on an upper surface of the transparent ohmic contact current spreading layer 206 exposed to the atmosphere. The p-type ohmic contact electrode and the electrode pad 302 are made of a material forming an ohmic contact interface with the transparent ohmic contact current spreading layer 206, for example, a metal such as Pt / Au, and lift-off. off) method.

12 is a cross-sectional view of a light emitting diode device in which a rear reflector is formed on a bottom surface of a patterned support substrate.

As shown in the drawing, as a final step of the group III-nitride-based semiconductor light emitting diode manufacturing process, a back reflector 303 is formed of a material having a high reflectivity on the back side of the patterned support substrate 101 to form a patterned support substrate ( A light emitting diode element including 101 is completed.

The material constituting the back reflector 303 preferably has a reflectance of 70% or more in a wavelength band of 600 nanometers (nm) or less. For example, aluminum (Al), silver (Ag), and rhodium (Rh) , Chromium (Cr), nickel (Ni), gold (Au) is formed of any one selected from the group consisting of.

FIG. 13 is a cross-sectional view of a light emitting diode device in which a front n-type electrode structure is formed in an entire region of an upper surface of a lower nitride based clad layer in which surface irregularities are not formed.

As shown, after the process described with reference to FIG. 10, the front n-type electrode structures 305 and 301 are formed on the exposed surface of the lower nitride-based cladding layer 203 of the n-type conductivity having no surface irregularities. The light emitting diode device including the supported substrate 101 is completed.

The front n-type electrode structures 305 and 301 form an ohmic contact interface with the entire upper surface of the lower nitride-based cladding layer 203 where surface irregularities are not formed, and have a wavelength band of 600 nm or less. A transparent ohmic contact electrode 305 having a transmittance of 70% or more and a reflective electrode pad 301 having a reflectance of 50% or more in a wavelength band of 600 nanometers (nm) or less and formed in a portion of the upper surface of the transparent ohmic contact electrode. Configure.

14 is a cross-sectional view of surface unevenness introduced into an upper surface of a lower nitride cladding layer.

As shown in FIG. 10, after the process described with reference to FIG. 10, the surface uneven surface 304 having a predetermined shape and dimension is formed through another solution or a dry etching process including KOH on the upper surface of the n-type conductive lower nitride-based cladding layer 203. To form a structure.

 FIG. 15 is a cross-sectional view of an n-type electrode structure, a p-type ohmic contact electrode, and an electrode pad formed on an upper surface of a lower nitride-based cladding layer having surface irregularities and an upper surface of a transparent ohmic contact current spreading layer, respectively.

As illustrated, a partial n-type electrode structure 301 is formed in a portion of the upper surface of the lower nitride-based cladding layer 203 exposed to the atmosphere, and at the same time, p is disposed on the upper surface of the transparent ohmic contact current spreading layer 206. The type ohmic contact electrode and the electrode pad 302 are formed.

The partial n-type electrode structure 301 is formed on the exposed surface of the lower nitride-based cladding layer 203 of the n-type conductivity having the surface irregularities 304 formed thereon, and may be formed using a lift-off method. The partial n-type electrode structure 301 has a predetermined shape and dimension in a portion of the upper surface of the lower nitride-based cladding layer 203 on which the surface irregularities 304 are formed, and is 50 in a wavelength band of 600 nm or less. The reflective ohmic contact electrode and the electrode pad which have a reflectance of% or more are comprised.

The p-type ohmic contact electrode and the electrode pad 302 are disposed on an upper surface of the transparent ohmic contact current spreading layer 206 exposed to the atmosphere. The p-type ohmic contact electrode and the electrode pad 302 are made of a material forming an ohmic contact interface with the transparent ohmic contact current spreading layer 206, for example, a metal such as Pt / Au, and lift-off. off) method.

16 is a cross-sectional view of a light emitting diode device in which a rear reflector is formed on a bottom surface of a patterned support substrate.

As shown in the drawing, as a final step of the group III-nitride semiconductor LED manufacturing process, a surface reflector 304 is formed by forming a back reflector 303 with a material having a high reflectivity on the back side of the patterned support substrate 101. And a light emitting diode element including a patterned support substrate 101 is completed.

The material constituting the back reflector 303 preferably has a reflectance of 70% or more in a wavelength band of 600 nanometers (nm) or less. For example, aluminum (Al), silver (Ag), and rhodium (Rh) , Chromium (Cr), nickel (Ni), gold (Au) is formed of any one selected from the group consisting of.

FIG. 17 is a cross-sectional view of a light emitting diode device in which a front n-type electrode structure is formed in an entire region of an upper surface of a lower nitride based clad layer having surface irregularities.

As shown in FIG. 14, after the process described with reference to FIG. 14, the front n-type electrode structures 305 and 301 are formed on the exposed surface of the lower nitride-based cladding layer 203 of the n-type conductivity having the surface irregularities. A light emitting diode device including a 304 and a patterned support substrate 101 is completed.

The front n-type electrode structures 305 and 301 form an ohmic contact interface with the entire upper surface of the lower nitride-based cladding layer 203 on which surface irregularities are formed, and at least 70% in a wavelength band of 600 nm or less. A transparent ohmic contact electrode 305 having a transmittance and a reflective electrode pad 301 having a reflectance of 50% or more in a wavelength band of 600 nanometers (nm) or less is formed on a portion of the upper surface of the transparent ohmic contact electrode.

Although the preferred embodiments of the present invention have been described in detail above, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

1 is a cross-sectional view of a group III-nitride semiconductor light emitting diode device shown as a first embodiment manufactured by the present invention,

2 is a cross-sectional view of a group III-nitride semiconductor light emitting diode device shown as a second embodiment of the present invention,

3 is a cross-sectional view of a group III-nitride semiconductor light emitting diode device shown as a third embodiment of the present invention,

4 is a cross-sectional view of a group III-nitride semiconductor light emitting diode device shown as a fourth embodiment manufactured by the present invention;

5 to 17 are cross-sectional views showing a group 3 nitride-based semiconductor LED device manufacturing process as an embodiment according to the present invention.

18 is a cross-sectional view showing a representative example of a group III nitride semiconductor light emitting diode device according to the related art.

Claims (24)

In the light emitting diode manufacturing method using a group III nitride semiconductor represented by the formula In x Al y Ga 1-x-y N (0≤x, 0≤y, x + y≤1), Preparing a growth substrate for growing a light emitting structure for a light emitting diode device; A light emitting diode device having a lower nitride cladding layer made of an n-type conductive semiconductor, a nitride active layer made of another semiconductor, and an upper nitride cladding layer made of a p-type semiconductor Forming a structure; Forming a transparent ohmic contact current spreading layer on an upper surface of the nitride based cladding layer of the light emitting structure for the light emitting diode device; Forming a wafer bonding layer on an upper surface of the transparent ohmic contact current spreading layer; Preparing a patterned supporting substrate; Forming a planarization layer on an upper surface of the patterned support substrate; Forming a wafer bonding layer on an upper surface of the planarization layer formed on the patterned support substrate; Contacting the two wafer bonding layers to wafer bond the growth substrate and the support substrate to form a composite; Separating a growth substrate from the wafer-bonded composite; Removing a portion of the light emitting structure for the light emitting diode device, exposing the transparent ohmic contact current spreading layer to air, and forming a p-type ohmic contact electrode and an electrode pad on an upper surface of the transparent ohmic contact current spreading layer; step; And Forming a partial n-type electrode structure on a portion of the upper surface of the lower nitride-based cladding layer; and manufacturing a group III-nitride-based semiconductor light emitting diode. The method of claim 1, Prior to forming a transparent ohmic contact current spreading layer on the upper nitride-based clad layer upper surface of the light emitting structure for the light emitting diode device, n-type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN, SiC, SiCN, MgN, ZnN single layer, p type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN single layer, or less than 5 nanometers (nm), or Group 3 via a superlattice composed of nitrides or carbon nitrides of group 2, 3 or 4 elements having different dopant and composition elements A device manufacturing method for a group nitride semiconductor light emitting diode. The method of claim 1, 700 ° C to have a high light transmittance characteristic of 70% or more in the wavelength range of 600 nm or less and a transparent ohmic contact current spreading layer to form an ohmic contact interface with the upper nitride-based cladding layer. A device manufacturing method of a group III nitride-based semiconductor light emitting diode which is subjected to heat treatment at the following temperature. The method of claim 1, A planarization layer is formed by growing a transparent material on the upper surface of the patterned support substrate using MOCVD, HVPE, MBE equipment or by depositing a transparent material using a sputter, evaporator, PLD, spin-coater equipment. A device manufacturing method of a group III nitride semiconductor light emitting diode. The method of claim 1, Devices of group III-nitride-based semiconductor light emitting diodes wafer bonded to a wafer bonding layer composed of a material having a high light transmittance of 70% or more in the wavelength region of 600 nanometers (nm) or less while having mechanically and thermally stable bonding strength Manufacturing method. The method of claim 1, Prior to forming the composite through wafer bonding, the light emitting structure for the light emitting diode device, the transparent ohmic contact spreading layer, and the wafer bonding layer formed on the upper surface of the growth substrate may have a predetermined shape and dimensions. A device manufacturing method of a group III-nitride semiconductor light emitting diode which performs an isolation process until the growth substrate is exposed to the atmosphere. The method of claim 1, The growth substrate may be separated by chemical-mechanical polishing (CMP), laser lift-off (LLO) using a photon beam of a specific wavelength band, or chemical lift using a wet etching solution. A device manufacturing method of a group III nitride semiconductor light emitting diode using a chemical lift-off (CLO) method. The method of claim 1, Prior to forming the partial n-type electrode structure on the upper surface of the lower nitride-based cladding layer, a group III-nitride semiconductor light emitting device which introduces a surface texture having a predetermined shape and dimension on the upper surface of the lower nitride-based cladding layer Device manufacturing method of diode. The method of claim 1, A partial n-type electrode structure comprising a reflective ohmic contact electrode and an electrode pad having a predetermined shape and dimension in a portion of an upper surface of the lower nitride-based cladding layer and having a reflectance of 50% or more in a wavelength band of 600 nm or less. A device manufacturing method of a group III nitride semiconductor light emitting diode to be formed. In the light emitting diode manufacturing method using a group III nitride semiconductor represented by the formula In x Al y Ga 1-x-y N (0≤x, 0≤y, x + y≤1), Preparing a growth substrate for growing a light emitting structure for a light emitting diode device; A light emitting diode device having a lower nitride cladding layer made of an n-type conductive semiconductor, a nitride active layer made of another semiconductor, and an upper nitride cladding layer made of a p-type semiconductor Forming a structure; Forming a transparent ohmic contact current spreading layer on an upper surface of the nitride based cladding layer of the light emitting structure for the light emitting diode device; Forming a wafer bonding layer on an upper surface of the transparent ohmic contact current spreading layer; Preparing a patterned supporting substrate; Forming a planarization layer on an upper surface of the patterned support substrate; Forming a wafer bonding layer on an upper surface of the planarization layer formed on the patterned support substrate; Contacting the two wafer bonding layers to wafer bond the growth substrate and the support substrate to form a composite; Separating a growth substrate from the wafer-bonded composite; Removing a portion of the light emitting structure for the light emitting diode device, exposing the transparent ohmic contact current spreading layer to air, and forming a p-type ohmic contact electrode and an electrode pad on an upper surface of the transparent ohmic contact current spreading layer; step; And And forming a front n-type electrode structure on the entire upper surface of the lower nitride-based cladding layer. The method of claim 10, Prior to forming a transparent ohmic contact current spreading layer on the upper nitride-based clad layer upper surface of the light emitting structure for the light emitting diode device, n-type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN, SiC, SiCN, MgN, ZnN single layer, p type conductive InGaN, GaN, AlInN, AlN, InN, AlGaN, AlInGaN single layer, or less than 5 nanometers (nm), or Group 3 via a superlattice composed of nitrides or carbon nitrides of group 2, 3 or 4 elements having different dopant and composition elements A device manufacturing method for a group nitride semiconductor light emitting diode. The method of claim 10, 700 ° C or less so as to have a transparent ohmic contact current spreading layer having a high light transmittance characteristic of 70% or more in a wavelength range of 600 nm or less and forming an ohmic contact interface with the upper nitride-based cladding layer. A device manufacturing method of a group III nitride-based semiconductor light emitting diode, which is subjected to a heat treatment at a temperature of. The method of claim 10, A planarization layer is formed by growing a transparent material on the upper surface of the patterned support substrate using MOCVD, HVPE, MBE equipment or by depositing a transparent material using a sputter, evaporator, PLD, spin-coater equipment. A device manufacturing method of a group III nitride semiconductor light emitting diode. The method of claim 10, Devices of group III-nitride-based semiconductor light emitting diodes wafer bonded to a wafer bonding layer composed of a material having a high light transmittance of 70% or more in the wavelength region of 600 nanometers (nm) or less while having mechanically and thermally stable bonding strength Manufacturing method. The method of claim 10, Prior to forming the composite through wafer bonding, the light emitting structure for the light emitting diode device, the transparent ohmic contact spreading layer, and the wafer bonding layer formed on the upper surface of the growth substrate may have a predetermined shape and dimensions. A device manufacturing method of a group III-nitride semiconductor light emitting diode which performs an isolation process until the growth substrate is exposed to the atmosphere. The method of claim 10, The growth substrate may be separated by chemical-mechanical polishing (CMP), laser lift-off (LLO) using a photon beam of a specific wavelength band, or chemical lift using a wet etching solution. A device manufacturing method of a group III nitride semiconductor light emitting diode using a chemical lift-off (CLO) method. The method of claim 10, Prior to forming the front n-type electrode structure on the upper surface of the lower nitride-based cladding layer, a group III nitride semiconductor light emitting device which introduces a surface texture having a predetermined shape and dimension on the upper surface of the lower nitride-based cladding layer Device manufacturing method of diode. The method of claim 10, Form an ohmic contact interface with the entire upper surface of the lower nitride-based cladding layer, and form a transparent ohmic contact electrode having a transmittance of 70% or more in a wavelength band of 600 nm or less and a portion of the upper surface of the transparent ohmic contact electrode; And a group III-nitride semiconductor light emitting diode having a front surface n-type electrode structure composed of reflective electrode pads having a reflectance of 50% or more in a wavelength band of 600 nm or less. A top planarization layer, a wafer bonding layer, a transparent ohmic contact current spreading layer, an upper nitride cladding layer made of a p-type conductive semiconductor, a nitride active layer, and an n-type conductive semiconductor on an upper surface of a patterned support substrate having a back reflector formed thereon. A group III nitride semiconductor light emitting diode device comprising a nitride cladding layer, a partial n-type electrode structure, and a p-type ohmic contact electrode and electrode pad. The method of claim 19, After removing a part of the light emitting structure for the light emitting diode device including the lower nitride-based cladding layer, the nitride-based active layer, and the upper nitride-based cladding layer, the p-type ohmic contact is formed on the upper surface of the transparent ohmic contact current spreading layer exposed to the atmosphere. A group III nitride semiconductor light emitting diode device characterized in that an electrode and an electrode pad are formed. The method of claim 19, Group III-nitride semiconductor light emitting diode device, characterized in that surface irregularities are interposed on the upper surface of the lower nitride-based cladding layer made of the n-type conductive semiconductor. A top planarization layer, a wafer bonding layer, a transparent ohmic contact current spreading layer, an upper nitride cladding layer made of a p-type conductive semiconductor, a nitride active layer, and an n-type conductive semiconductor on an upper surface of a patterned support substrate having a back reflector formed thereon. A group III nitride semiconductor light emitting diode device comprising a nitride cladding layer, a front surface n-type electrode structure, and a p-type ohmic contact electrode and an electrode pad. The method of claim 22, After removing a part of the light emitting structure for the light emitting diode device including the lower nitride-based cladding layer, the nitride-based active layer, and the upper nitride-based cladding layer, the p-type ohmic contact is formed on the upper surface of the transparent ohmic contact current spreading layer exposed to the atmosphere. A group III nitride semiconductor light emitting diode device characterized in that an electrode and an electrode pad are formed. The method of claim 22, Group III-nitride semiconductor light emitting diode device, characterized in that surface irregularities are interposed on the upper surface of the lower nitride-based cladding layer made of the n-type conductive semiconductor.

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