CN110718613A - Light-emitting diode chip and method of making the same - Google Patents

Abstract

The invention discloses a light-emitting diode chip and a manufacturing method thereof, belonging to the technical field of semiconductors. The light-emitting diode chip includes a silicon substrate, a bonding layer, a metal reflective layer, a transparent conductive layer, a filling layer, a current blocking layer, a window layer, a P-type confinement layer, an active layer, an N-type confinement layer and electrodes; the silicon a substrate, the bonding layer, the metal reflective layer, the transparent conductive layer, the filling layer, the window layer, the P-type confinement layer, the active layer, the N-type confinement layer, and The electrodes are stacked in sequence, a plurality of through holes extending from the transparent conductive layer to the window layer are arranged in the filling layer, and the current blocking layer is arranged in the through holes; the current blocking layer The material is magnesium difluoride, and the material of the filling layer and the transparent conductive layer is one of indium tin oxide, tungsten oxide, and tungsten-doped indium tin oxide. The invention can improve the front light emitting efficiency of the red LED chip.

Description

Light-emitting diode chip and method of making the same

technical field

The invention relates to the technical field of semiconductors, in particular to a light emitting diode epitaxial wafer and a manufacturing method thereof.

Background technique

Light Emitting Diode (English: Light Emitting Diode, LED for short) is a semiconductor electronic component that can emit light.

The chip is the core component of the LED, including an epitaxial wafer and an N-type electrode and a P-type electrode respectively arranged on the epitaxial wafer. For a red light LED chip, the epitaxial wafer includes a GaAs substrate and an N-type confinement layer, an active layer, a P-type confinement layer and a window layer sequentially grown on the GaAs substrate. The GaAs substrate absorbs light. In order to prevent the light emitted by the active layer from being absorbed by the GaAs substrate, the silicon substrate can be bonded to the window layer as a P-type electrode, and then the GaAs substrate is removed on the N-type confinement layer to set the N-type electrode.

In the process of realizing the present invention, the inventor found that the prior art has at least the following problems:

The light emitted by the active layer will be emitted in all directions, and only part of the light will be emitted from the N-type confinement layer, so the front light emission efficiency of the red LED chip is very low.

SUMMARY OF THE INVENTION

The embodiments of the present invention provide a light emitting diode chip and a manufacturing method thereof, which can effectively improve the front light extraction efficiency of the light emitting diode chip. The technical solution is as follows:

In one aspect, an embodiment of the present invention provides a light-emitting diode chip, the light-emitting diode chip includes a silicon substrate, a bonding layer, a metal reflection layer, a transparent conductive layer, a filling layer, a current blocking layer, a window layer, and a P-type confinement layer , active layer, N-type confinement layer and electrodes; the silicon substrate, the bonding layer, the metal reflective layer, the transparent conductive layer, the filling layer, the window layer, the P-type confinement layer, the active layer, the N-type confinement layer and the electrode are stacked in sequence, a plurality of through holes extending from the transparent conductive layer to the window layer are arranged in the filling layer, the current The blocking layer is arranged in the through hole; the material of the current blocking layer is magnesium difluoride, and the materials of the filling layer and the transparent conductive layer are indium tin oxide, tungsten oxide, and tungsten-doped indium tin oxide. a kind of.

Optionally, the thickness of the current blocking layer and the filling layer is 100 nm to 140 nm, and the thickness of the transparent conductive layer is 100 nm to 300 nm.

Further, the diameter of the through holes is 6 μm˜10 μm, and the distance between two adjacent through holes is 10 μm˜20 μm.

Optionally, the material of the metal reflective layer is silver.

Further, the light-emitting diode chip further includes a titanium-tungsten alloy layer, and the titanium-tungsten alloy layer is disposed between the metal reflective layer and the bonding layer.

Further, the content of the titanium component in the titanium-tungsten alloy layer is 10%.

Optionally, the light-emitting diode chip further includes a current spreading layer, a transition layer and a light extraction layer, the current spreading layer, the transition layer and the light extraction layer are sequentially stacked on the N-type confinement layer, and the electrode The material of the current spreading layer, the transition layer and the light extraction layer is N-type doped AlGaInP, and the content of the aluminum component in the current spreading layer is It is less than the content of the aluminum component in the transition layer, and the content of the aluminum component in the transition layer is less than the content of the aluminum component in the light emitting layer.

Further, the content of the aluminum component in the current spreading layer is 20% to 40%, the content of the aluminum component in the transition layer is 35% to 60%, and the content of the aluminum component in the light emitting layer is 55%. %～70%.

Further, the projection of the electrode on the light emitting layer is a circle; the light emitting diode chip further includes an ohmic contact layer, the material of the ohmic contact layer is N-type doped gallium arsenide, and the ohmic contact The layer is arranged between the electrode and the light-exiting layer; the projection of the ohmic contact layer on the light-extracting layer is annular, and the outer diameter of the annular shape is smaller than the diameter of the circle; or, the ohmic contact The projection of the layer on the light emitting layer is a plurality of arcs distributed at intervals, and the outer diameter of the arc is equal to the diameter of the circle.

On the other hand, an embodiment of the present invention provides a method for fabricating a light-emitting diode chip, the fabrication method comprising:

The etching stop layer, the N-type confinement layer, the active layer, the P-type confinement layer and the window layer are sequentially grown on the GaAs substrate;

forming a current blocking layer and a filling layer on the window layer, the filling layer is provided with a plurality of through holes extending to the window layer, and the current blocking layer is arranged in the through holes;

A transparent conductive layer, a metal reflection layer, and a first bonding layer are sequentially laid on the current blocking layer and the filling layer;

forming a second bonding layer on the silicon substrate;

bonding the second bonding layer and the first bonding layer together;

removing the gallium arsenide substrate and the etch stop layer;

An electrode is provided on the N-type confinement layer.

The beneficial effects brought by the technical solutions provided in the embodiments of the present invention are:

By adding a current blocking layer, a filling layer, a transparent conductive layer and a metal reflection layer between the window layer and the bonding layer, the material of the current blocking layer is magnesium difluoride, and the material of the filling layer and the transparent conductive layer is indium tin oxide, oxide One of tungsten and tungsten-doped indium tin oxide, the refractive index of the current blocking layer and the transparent conductive layer are quite different (the refractive index of magnesium difluoride is 1.38, the refractive index of indium tin oxide is 1.62, and the refractive index of tungsten oxide is 1.62). The ratio is 1.65, and the refractive index of tungsten-doped indium tin oxide is 1.62-1.65); plus the transparent conductive layer is arranged on the current blocking layer, the current blocking layer and the transparent conductive layer can form a single period Bragg mirror. Moreover, the metal reflective layer is arranged on the transparent conductive layer, so an omnidirectional mirror is formed between the window layer and the bonding layer, which can reflect the light emitted from the active layer to the P-type confinement layer to the N-type confinement layer for emission, improving the red light. The front luminous efficiency of the LED chip.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

FIG. 1 is a schematic structural diagram of a light-emitting diode chip provided by an embodiment of the present invention;

2 is a schematic structural diagram of a current blocking layer and a filling layer provided by an embodiment of the present invention;

3 is a schematic structural diagram of an ohmic contact layer provided by an embodiment of the present invention;

4 is a schematic structural diagram of another ohmic contact layer provided by an embodiment of the present invention;

FIG. 5 is a flowchart of a method for fabricating a light-emitting diode chip according to an embodiment of the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

The embodiments of the present invention provide a light emitting diode chip, especially a red light LED chip. FIG. 1 is a schematic structural diagram of a light emitting diode chip according to an embodiment of the present invention. 1, the light emitting diode chip includes a silicon substrate 10, a bonding layer 20, a metal reflective layer 31, a transparent conductive layer 32, a filling layer 33, a current blocking layer 34, a window layer 41, a P-type confinement layer 42, an active layer 43 , N-type confinement layer 44 and electrode 50 . The silicon substrate 10 , the bonding layer 20 , the metal reflection layer 31 , the transparent conductive layer 32 , the filling layer 33 , the window layer 41 , the P-type confinement layer 42 , the active layer 43 , the N-type confinement layer 44 and the electrode 50 are stacked in sequence.

FIG. 2 is a schematic structural diagram of a current blocking layer and a filling layer provided by an embodiment of the present invention. Referring to FIG. 2 , a plurality of through holes extending from the transparent conductive layer 32 to the window layer 41 are provided in the filling layer 33 , and the current blocking layer 34 is disposed in the through holes. The material of the current blocking layer 34 is magnesium difluoride, and the material of the filling layer 33 and the transparent conductive layer 32 is one of indium tin oxide, tungsten oxide, and tungsten-doped indium tin oxide.

In the embodiment of the present invention, a current blocking layer, a filling layer, a transparent conductive layer and a metal reflection layer are added between the window layer and the bonding layer. The material of the current blocking layer is magnesium difluoride, and the material of the filling layer and the transparent conductive layer is oxide One of indium tin, tungsten oxide, and tungsten-doped indium tin oxide, the refractive index difference between the current blocking layer and the transparent conductive layer is relatively large (the refractive index of magnesium difluoride is 1.38, the refractive index of indium tin oxide is 1.62, The refractive index of tungsten oxide is 1.65, and the refractive index of tungsten-doped indium tin oxide is 1.62 to 1.65); plus the transparent conductive layer is arranged on the current blocking layer, the current blocking layer and the transparent conductive layer can form a single period Bragg mirror. Moreover, the metal reflective layer is arranged on the transparent conductive layer, so an omnidirectional mirror is formed between the window layer and the bonding layer, which can reflect the light emitted from the active layer to the P-type confinement layer to the N-type confinement layer for emission, improving the red light. The front luminous efficiency of the LED chip. In addition, magnesium difluoride is an insulating material, indium tin oxide, tungsten oxide, and tungsten-doped indium tin oxide are conductive materials, and the current blocking layer is arranged in a plurality of through holes in the filling layer, which will not affect the current injection window layer. , which is also conducive to the uniform injection of current into the window layer.

Optionally, the thickness of the current blocking layer 34 and the filling layer 33 may be 100 nm to 140 nm, and the thickness of the transparent conductive layer 32 may be 100 nm to 300 nm, so that the thicknesses of the current blocking layer 34 and the transparent conductive layer 32 are matched with each other, which is beneficial to Implement Bragg reflection.

Further, as shown in FIG. 2 , the diameter d of the through holes may be 6 μm˜10 μm, and the spacing s of two adjacent through holes may be 10 μm˜20 μm. The distance between two adjacent through holes is about twice the diameter of the through holes, which is conducive to the uniform injection of current into the window layer.

Optionally, the material of the metal reflective layer 31 may be silver. The high reflectivity of silver is conducive to the formation of an omnidirectional mirror and improves the front light emitting efficiency of the chip.

Exemplarily, the surface roughness of the metal reflective layer 31 is 0.5 nm to 3 nm, and the reflectivity to light with wavelengths of 550 nm to 650 nm can be maintained above 95%.

Further, the light-emitting diode chip may further include a titanium-tungsten alloy layer 35 , and the titanium-tungsten alloy layer 35 is disposed between the metal reflective layer 31 and the bonding layer 20 . Titanium-tungsten alloy has good diffusion barrier properties and adhesion properties, which can not only prevent silver from diffusing into the bonding layer, but also facilitate the fixing of the bonding layer and improve the reliability of the chip.

Furthermore, the content of the titanium component in the titanium-tungsten alloy layer 35 can be 10%, and the reliability of the chip is good.

Optionally, the light-emitting diode chip may further include a current spreading layer 45, a transition layer 46 and a light extraction layer 47, the current spreading layer 45, the transition layer 46 and the light extraction layer 47 are sequentially stacked on the N-type confinement layer 44, and the electrode 50 is arranged on the N-type confinement layer 44. on a partial area of the light emitting layer 47 . The materials of the current spreading layer 45, the transition layer 46 and the light emitting layer 47 are N-type doped (such as silicon) AlGaInP, and the content of the aluminum component in the current spreading layer 45 is less than the content of the aluminum component in the transition layer 46, The content of the aluminum component in the transition layer 46 is smaller than the content of the aluminum component in the light extraction layer 47 . The content of aluminum components in the current spreading layer is the lowest, and the doping concentration of silicon can be increased to more than 4*10 ¹⁸ , which is beneficial to the current expansion; the content of aluminum components in the light-emitting layer is the highest, which can facilitate roughening and improve the chip performance. Front light emitting efficiency; the content of aluminum components in the transition layer is between the current spreading layer and the light emitting layer, which can play a transitional role to avoid the large difference in the content of aluminum components in the current spreading layer and the light emitting layer, which will affect the crystal quality of the chip .

Further, the content of the aluminum component in the current spreading layer 45 may be 20% to 40%, the content of the aluminum component in the transition layer 46 may be 35% to 60%, and the content of the aluminum component in the light emitting layer 47 may be 55%. %～70%, with good effect.

Optionally, the projection of the electrode 50 on the light emitting layer 47 may be circular.

Further, the light emitting diode chip may further include an ohmic contact layer 48, the material of the ohmic contact layer 48 is N-type doped gallium arsenide, the ohmic contact layer 48 is arranged between the electrode 50 and the light extraction layer 47, and the ohmic contact layer 48 is located between the electrode and the epitaxial layer. The realization of ohmic contact between the materials facilitates the electrode to inject current into the epitaxial material.

FIG. 3 is a schematic structural diagram of an ohmic contact layer according to an embodiment of the present invention. Referring to FIG. 3 , in an implementation manner of this embodiment, the projection of the ohmic contact layer 48 on the light emitting layer 47 may be annular, and the outer diameter of the annular shape is smaller than the diameter of the circular shape.

FIG. 4 is a schematic structural diagram of another ohmic contact layer provided by an embodiment of the present invention. Referring to FIG. 4 , in another implementation manner of this embodiment, the projection of the ohmic contact layer 48 on the light emitting layer 47 may be a plurality of arcs distributed at intervals, and the outer diameter of the arc is equal to the diameter of the circle.

The above two implementations both reduce the occupied area of the ohmic contact layer as much as possible on the basis of realizing the ohmic contact between the electrode and the epitaxial material, and avoid light absorption by gallium arsenide.

Optionally, the light emitting diode chip may further include a protective layer 60, the material of the protective layer 60 is Si ₃ N ₄ , and the protective layer 60 is disposed on the side of the chip to prevent the epitaxial material from being corroded by oxygen and water vapor in the air. In practical applications, the light extraction layer 47 is provided with a groove extending to the window layer 41 , so that the protective layer 60 is deposited on the sidewalls of the groove.

In this embodiment, the size of the chip may be 5 mils to 10 mils. The material of the N-type confinement layer 44 can be N-type doped AlInP, the material of the light emitting layer 43 can be AlGaInP, the material of the P-type confinement layer 42 can be P-type doped AlInP, the window layer 41 may be P-type doped gallium phosphide. The bonding layer 20 may include a titanium layer, a platinum layer, a gold layer, an indium layer, a gold layer, a platinum layer and a titanium layer stacked in sequence, and the electrode 50 may include a gold layer, a gold-germanium-nickel alloy layer, a gold layer, and a titanium layer stacked in sequence. layer, platinum layer, gold layer. In practical applications, a silicon substrate can be used as the electrode, or a titanium layer and a gold layer can be sequentially deposited on the silicon substrate as the electrode.

Exemplarily, the thickness of the metal reflective layer 31 may be 200nm-500nm, the thickness of the titanium-tungsten alloy layer may be 100nm-300nm; the thickness of the titanium layer in the bonding layer may be 100nm, the thickness of the platinum layer may be 80nm, and the thickness of the gold layer may be 100nm. The thickness of the indium layer may be 400 nm, the thickness of the indium layer may be 2 μm to 4 μm, and the deposition rate of the indium layer may be greater than 180 nm/s; the thickness of the titanium layer in the electrode on the silicon substrate may be 100 nm, and the thickness of the gold layer may be 400 nm. The doping concentration of the N-type dopant in the ohmic contact layer may be 7*10 ¹⁸ /cm ³ or more, and the doping concentration of the P-type dopant in the window layer may be 8*10 ¹⁹ /cm ³ or more.

The embodiment of the present invention provides a manufacturing method of a light emitting diode chip, which is suitable for manufacturing the light emitting diode chip shown in FIG. 1 . FIG. 5 is a flowchart of a method for fabricating a light-emitting diode chip according to an embodiment of the present invention. Referring to Figure 5, the manufacturing method includes:

Step 201 : sequentially growing an etch stop layer, an N-type confinement layer, an active layer, a P-type confinement layer and a window layer on the gallium arsenide substrate.

Optionally, this step 201 may include:

Etch stop layer, N-type confinement layer, active layer, P-type confinement layer and window layer are sequentially grown on GaAs substrate by metal-organic chemical vapor deposition (English: Metal-organic Chemical VaporDeposition, MOCVD for short) technology .

Step 202 : forming a current blocking layer and a filling layer on the window layer, the filling layer is provided with a plurality of through holes extending to the window layer, and the current blocking layer is arranged in the through holes.

Optionally, this step 202 may include:

Using electron beam evaporation technology to lay magnesium difluoride on the window layer;

Using photolithography technology and dry etching technology to pattern magnesium difluoride to form a current blocking layer;

A filling layer is formed between the patterns of the current blocking layer using a sputtering technique.

In practical applications, when the materials used for the filling layer and the transparent conductive layer are the same, the filling layer and the transparent conductive layer can be deposited together; when the materials used for the filling layer and the transparent conductive layer are different, the current blocking layer and A filling layer is deposited between the current blocking layers, the filling layer on the current blocking layer is removed, and finally a transparent conductive layer is deposited on the current blocking layer and the filling layer.

Step 203: Lay a transparent conductive layer, a metal reflective layer, and a first bonding layer on the current blocking layer and the filling layer in sequence.

Optionally, this step 203 may include:

The transparent conductive layer, the metal reflection layer and the first bonding layer are sequentially laid on the current blocking layer and the filling layer by sputtering technology.

Using sputtering technology, the film has good compactness and strong current expansion.

In practical applications, after the metal reflective layer is formed, annealing can be performed by passing nitrogen gas at a temperature of 250°C to 500°C. In addition, when forming, vacuum is drawn first, then argon gas is introduced and the pressure is kept at 0.2Pa-10Pa.

Step 204 : forming a second bonding layer on the silicon substrate.

Optionally, this step 203 may include:

The second bonding layer is formed on the silicon substrate using sputtering technology.

Step 205: Bond the second bonding layer and the first bonding layer together.

Optionally, this step 205 may include:

The bonding is carried out at a temperature of 280°C to 320°C, and the bonding is relatively firm.

Step 206: Remove the gallium arsenide substrate and the etch stop layer.

Optionally, this step 206 may include:

Wet etching of GaAs substrates and etch stop layers.

Step 207: Disposing electrodes on the N-type confinement layer.

Optionally, this step 207 may include:

A negative photoresist with a set pattern is formed on the N-type confinement layer by photolithography;

The electrode material is laid on and between the negative photoresist by electron beam evaporation technology;

The negative photoresist is stripped off, leaving the electrode material to form the electrode.

Using negative photoresist, the electrode is narrow on the top and wide on the bottom, and the adhesion is better.

Optionally, before step 207, the manufacturing method further includes:

Epitaxial growth of current spreading layer, transition layer, light extraction layer and ohmic contact layer on the N-type confinement layer;

The ohmic contact layer is patterned using photolithography and ICP techniques.

Further, after patterning, the ohmic contact layer is annealed at a temperature of 300° C., which is beneficial to form ohmic contact with the electrodes.

Optionally, after step 207, the manufacturing method further includes:

Using plasma etching technology, a groove extending to the window layer is formed on the light emitting layer;

Chemically corrode the light emitting layer and roughen the light emitting layer;

Use PECVD technology to form protective layers on the front and sides of the chip;

The protective layer on the front side of the chip is removed by photolithography and dry etching.

Optionally, the manufacturing method may also include:

Thinning of the silicon substrate.

Exemplarily, the thickness of the silicon substrate may be thinned to 130 μm˜150 μm.

Further, the manufacturing method can also include:

Deposit a titanium layer and a gold layer sequentially on the thinned silicon substrate;

Annealed at 200°C to increase adhesion and form good electrical contacts.

After the products obtained in the above steps are laser cut and separated, an LED chip can be obtained, the luminous brightness of the front side is increased by 15%, and the reliability is high.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (10)

1. A light-emitting diode chip, characterized in that the light-emitting diode chip comprises a silicon substrate (10), a bonding layer (20), a metal reflection layer (31), a transparent conductive layer (32), and a filling layer (33) , a current blocking layer (34), a window layer (41), a P-type confinement layer (42), an active layer (43), an N-type confinement layer (44) and an electrode (50); the silicon substrate (10), The bonding layer (20), the metal reflection layer (31), the transparent conductive layer (32), the filling layer (33), the window layer (41), the P-type confinement layer ( 42), the active layer (43), the N-type confinement layer (44) and the electrode (50) are stacked in sequence, and the filling layer (33) is provided with a plurality of layers from the transparent conductive layer (32) a through hole extending to the window layer (41), the current blocking layer (34) is arranged in the through hole; the material of the current blocking layer (34) is magnesium difluoride, the The material of the filling layer (33) and the transparent conductive layer (32) is one of indium tin oxide, tungsten oxide, and tungsten-doped indium tin oxide. 2 . The light-emitting diode chip according to claim 1 , wherein the current blocking layer ( 34 ) and the filling layer ( 33 ) have a thickness of 100 nm to 140 nm, and the transparent conductive layer ( 32 ) has a thickness of 100 nm to 140 nm. 3 . It is 100nm～300nm. 3 . The light-emitting diode chip according to claim 2 , wherein the diameter of the through hole is 6 μm˜10 μm, and the distance between two adjacent through holes is 10 μm˜20 μm. 4 . 4. The light-emitting diode chip according to any one of claims 1 to 3, wherein the material of the metal reflective layer (31) is silver. 5. The light-emitting diode chip according to claim 4, wherein the light-emitting diode chip further comprises a titanium-tungsten alloy layer (35), and the titanium-tungsten alloy layer (35) is disposed on the metal reflective layer (31). ) and the bonding layer (20). 6. The light-emitting diode chip according to claim 5, wherein the content of the titanium component in the titanium-tungsten alloy layer (35) is 10%. 7. The light-emitting diode chip according to any one of claims 1 to 3, wherein the light-emitting diode chip further comprises a current spreading layer (45), a transition layer (46) and a light exit layer (47), the The current spreading layer (45), the transition layer (46) and the light emitting layer (47) are sequentially stacked on the N-type confinement layer (44), and the electrode (50) is arranged on the light emitting layer (47) ); the materials of the current spreading layer (45), the transition layer (46) and the light extraction layer (47) are N-type doped AlGaInP, the current spreading layer (45) The content of the aluminum component in the transition layer (46) is less than the content of the aluminum component in the transition layer (46), and the content of the aluminum component in the transition layer (46) is less than the content of the aluminum component in the light emitting layer (47). 8 . The light-emitting diode chip according to claim 7 , wherein the content of the aluminum component in the current spreading layer ( 45 ) is 20% to 40%, and the content of the aluminum component in the transition layer ( 46 ) is 20% to 40%. 9 . The content is 35%-60%, and the content of the aluminum component in the light emitting layer (47) is 55%-70%. 9. The light-emitting diode chip according to claim 7, wherein the projection of the electrode (50) on the light-emitting layer (47) is a circle; the light-emitting diode chip further comprises an ohmic contact layer (48) ), the material of the ohmic contact layer (48) is N-type doped gallium arsenide, and the ohmic contact layer (48) is arranged between the electrode (50) and the light emitting layer (47); The projection of the ohmic contact layer (48) on the light emitting layer (47) is annular, and the outer diameter of the annular shape is smaller than the diameter of the circle; or, the ohmic contact layer (48) is on the light emitting layer The projection on (47) is a plurality of arcs distributed at intervals, and the outer diameter of the arcs is equal to the diameter of the circle. 10. A manufacturing method of a light-emitting diode chip, wherein the manufacturing method comprises: Growing an etching stop layer, an N-type confinement layer, an active layer, a P-type confinement layer and a window layer in sequence on the GaAs substrate; forming a current blocking layer and a filling layer on the window layer, the filling layer is provided with a plurality of through holes extending to the window layer, and the current blocking layer is arranged in the through holes; A transparent conductive layer, a metal reflection layer, and a first bonding layer are sequentially laid on the current blocking layer and the filling layer; forming a second bonding layer on the silicon substrate; bonding the second bonding layer and the first bonding layer together; removing the gallium arsenide substrate and the etch stop layer; An electrode is provided on the N-type confinement layer.

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