An epitaxial structure of a light-emitting diode and its fabrication method, a light-emitting diode

Abstract

The application provides a light emitting diode epitaxial structure and a manufacturing method thereof and a light emitting diode, and relates to the field of semiconductor manufacturing.The light emitting diode epitaxial structure comprises a first type semiconductor layer, a light emitting layer arranged on one side of the first type semiconductor layer, and a second type semiconductor layer arranged on the side of the light emitting layer away from the first type semiconductor layer; wherein the first type semiconductor layer comprises a first type ohmic contact layer and a first type reflection layer of an arsenic system; the first type reflection layer is arranged between the first type ohmic contact layer and the light emitting layer; the first type reflection layer is used for current spreading of the first type ohmic contact layer and reflection of light of the light emitting layer.The application can effectively improve the light emitting efficiency of the light emitting diode.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing, and more particularly to an epitaxial structure of a light-emitting diode and its fabrication method, and a light-emitting diode. Background Technology

[0002] A light-emitting diode (LED) is a semiconductor device that converts electric current into light within a specific wavelength range. Its light-emitting principle relies on the energy difference of electrons moving between n-type and p-type semiconductors, releasing energy in the form of light. Therefore, LEDs are called cold light sources. They possess advantages such as low power consumption, small size, high brightness, easy integration with integrated circuits, and high reliability, making them widely used as light sources. Furthermore, with the maturity of LED technology, LED displays or Micro LED (micro-LED) displays, which directly utilize LEDs as self-emissive display pixels, are gradually becoming more widely used.

[0003] Micro LEDs, with their small size and matrix configuration, offer advantages over LCD and OLED in wearable products and high-resolution displays. The main challenge currently facing Micro LEDs is their low luminous brightness under low current density conditions. The only solution is to use a matrix configuration to improve overall brightness, which inherently increases the complexity of the manufacturing process. Summary of the Invention

[0004] In view of the problems existing in the prior art, the present invention proposes an epitaxial structure of a light-emitting diode and its preparation method, and a light-emitting diode, which mainly solves the problem of low light-emitting brightness of existing light-emitting diodes.

[0005] To achieve the above and other objectives, the technical solution adopted by the present invention is as follows.

[0006] This application provides an epitaxial structure for a light-emitting diode, comprising: a first type semiconductor layer; a light-emitting layer disposed on one side of the first type semiconductor layer; and a second type semiconductor layer disposed on the side of the light-emitting layer opposite to the first type semiconductor layer; wherein the first type semiconductor layer includes a first type ohmic contact layer and an arsenide-based first type reflective layer, the first type reflective layer being disposed between the first type ohmic contact layer and the light-emitting layer, the first type reflective layer spreading current through the first type ohmic contact layer and reflecting light from the light-emitting layer.

[0007] In one embodiment of this application, the first type of reflective layer includes a plurality of substructure layers, each of the substructure layers including a plurality of loop pairs, and each loop pair is obtained by stacking a first reflective sublayer and a second reflective sublayer.

[0008] In one embodiment of this application, the material of the first reflective sublayer includes Al. x1 Ga 1-x1 As, the material of the second reflective sublayer includes Al. x2 Ga 1-x2 As, where x1 ranges from 0.5 to 0.55 and x2 ranges from 0.9 to 0.95.

[0009] In one embodiment of this application, the A1 component is the same in each of the cycle pairs.

[0010] In one embodiment of this application, the first type of reflective layer includes a first substructure layer, a second substructure layer, and a third substructure layer stacked sequentially toward the light-emitting layer, wherein the doping concentration range and doping elements of the first substructure layer, the second substructure layer, and the third substructure layer are the same.

[0011] In one embodiment of this application, the doping element includes magnesium, and the doping concentration ranges from 9x10⁻⁶. 17 cm -3 Up to 2x10 18 cm -3 Between these layers, the growth thickness of the first sub-reflective layer and the second sub-reflective layer of the first substructure layer are both between 45 nm and 55 nm, the growth thickness of the first sub-reflective layer and the second sub-reflective layer of the second substructure layer are between 40 nm and 50 nm, and the growth thickness of the first sub-reflective layer and the second sub-reflective layer of the third substructure layer are between 35 nm and 45 nm.

[0012] In one embodiment of this application, the number of loop pairs in the first substructure layer is between 3 and 8 pairs, the number of loop pairs in the second substructure is between 3 and 8 pairs, and the number of loop pairs in the third substructure is between 17 and 22 pairs.

[0013] This application also provides a method for fabricating an epitaxial structure of a light-emitting diode, comprising: providing a substrate; fabricating an epitaxial structure on the substrate, the epitaxial structure comprising: a first type semiconductor layer disposed on one side of the substrate; a light-emitting layer disposed on one side of the first type semiconductor layer; and a second type semiconductor layer disposed on the side of the light-emitting layer opposite to the first type semiconductor layer; wherein the first type semiconductor layer comprises a first type ohmic contact layer and a first type reflective layer formed by stacking multiple arsenide semiconductor layers, the first type reflective layer being disposed between the first type ohmic contact layer and the light-emitting layer, the first type reflective layer spreading current through the first type ohmic contact layer and reflecting light from the light-emitting layer.

[0014] In one embodiment of this application, the preparation process of the first type of reflective layer includes: setting the temperature of the reaction chamber to 650-670°C and the pressure to 50 mbar; introducing arsine as a group V source, hydrogen as a carrier gas, and trimethylaluminum and trimethylgallium as group III sources into the first type of ohmic contact layer to form the first type of reflective layer composed of multiple substructure layers, wherein each substructure layer includes multiple sets of cycle pairs, and each set of cycle pairs is obtained by stacking the first reflective sublayer and the second reflective sublayer.

[0015] This application also provides a light-emitting diode, comprising: an epitaxial structure, the epitaxial structure comprising: a first type semiconductor layer; a light-emitting layer disposed on one side of the first type semiconductor layer; and a second type semiconductor layer disposed on the side of the light-emitting layer opposite to the first type semiconductor layer; wherein the first type semiconductor layer comprises a first type ohmic contact layer and an arsenide-based first type reflective layer, the first type reflective layer being disposed between the first type ohmic contact layer and the light-emitting layer, the first type reflective layer spreading current through the first type ohmic contact layer and reflecting light from the light-emitting layer; a first electrode electrically connected to the first type ohmic contact layer; and a second electrode electrically connected to the second type semiconductor layer.

[0016] As described above, the light-emitting diode epitaxial structure and its fabrication method provided in this application, as well as the light-emitting diode itself, have the following beneficial effects.

[0017] This application provides a first type of reflective layer between the ohmic contact layer and the light-emitting layer. The first type of reflective layer can not only extend the current but also improve the reflection of the light source, thereby enhancing the luminous efficiency. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the epitaxial structure of a light-emitting diode in one embodiment of this application.

[0019] Figure 2 This is a schematic diagram of the structure of a first type of reflective layer in one embodiment of this application.

[0020] Figure 3 This application describes a method for fabricating a light-emitting diode epitaxial structure in one embodiment.

[0021] Figure 4 This is a schematic diagram of the structure of a light-emitting diode in one embodiment of this application.

[0022] Explanation of icon numbers:

[0023] 101-First type semiconductor layer, 1011-P-type buffer layer, 1012-P-type etch stop layer, 1013-P-type ohmic contact layer, 1014-P-type reflective layer, 1015-P-type confinement layer, 1016-P-type waveguide layer, 102-Light emitting layer, 103-Second type semiconductor layer, 1031-N-type waveguide layer, 1032-N-type confinement layer, 1033-N-type window layer, 104-First electrode, 105-Second electrode. Detailed Implementation

[0024] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0025] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0026] Please see Figure 1 , Figure 1 This is a schematic diagram of the epitaxial structure of a light-emitting diode (LED) according to an embodiment of this application. The LED epitaxial structure provided in this application includes a first-type semiconductor layer 101, a light-emitting layer 102, and a second-type semiconductor layer 103. The light-emitting layer 102 can be disposed on one side of the first-type semiconductor layer 101, and the second-type semiconductor layer 103 can be disposed on the side of the light-emitting layer 102 opposite to the first-type semiconductor layer 101. The first-type semiconductor layer 101 includes a first-type ohmic contact layer and an arsenide-based first-type reflective layer. The first-type reflective layer is disposed between the first-type ohmic contact layer and the light-emitting layer 102, and it spreads the current through the first-type ohmic contact layer and reflects the light from the light-emitting layer 102.

[0027] Please see Figure 1In one embodiment, the aforementioned first type can be P-type, and the second type can be N-type. The first type semiconductor layer 101 may include a P-type buffer layer 1011, a P-type etch stop layer 1012, a P-type ohmic contact layer 1013, a P-type reflective layer 1014, a P-type confinement layer 1015, and a P-type waveguide layer 1016 stacked sequentially. The light-emitting layer 102 may employ a multi-quantum-well structure as a light source. The second type semiconductor layer 103 includes an N-type waveguide layer 1031, an N-type confinement layer 1032, and an N-type window layer 1033 stacked sequentially, wherein the P-type waveguide layer 1016 and the N-type waveguide layer 1031 are respectively disposed on opposite sides of the light-emitting layer 102. The P-type buffer layer 1011 can be made of P-type doped gallium arsenide (GaAs), the P-type etching stop layer 1012 can be made of P-type doped gallium phosphide (GaP), the P-type ohmic contact layer 1013 can be made of P-type doped GaAs (gaAs) (gallium arsenide), the P-type confinement layer 1015 and the N-type confinement layer 1032 can both be made of aluminum indium phosphide (AlInP), the N-type window layer 1033 can be made of N-type doped gallium phosphide (GaP), and the P-type reflective layer 1014 can be made of an arsenide-based material. Traditional red light-emitting diodes typically use aluminum gallium indium phosphide (AlGaInP) as the current spreading layer. However, this embodiment replaces the traditional current spreading layer with an arsenide-based P-type reflective layer 1014, which not only serves to spread the current but also reflects light from a multi-quantum-well light source, improving the luminous efficiency of the single diode.

[0028] Please see Figure 2 , Figure 2 This is a schematic diagram of the structure of a first type of reflective layer in one embodiment of this application. The first type of reflective layer may include multiple sub-structure layers, each sub-structure layer including multiple sets of loop pairs, and each set of loop pairs is formed by stacking a first reflective sub-layer and a second reflective sub-layer. Specifically, each sub-structure layer can act as a distributed Bragg reflector (DBR). When light emitted from a multi-quantum-well light source passes through the sub-structure layer, due to the alternating stacking of the first and second reflective sub-layers, and the different refractive indices of the first and second reflective sub-layers, the light reflected back from each sub-layer interferes due to the change in phase angle, forming strong reflected light. The periodic stacking of multiple loop pairs can effectively improve the luminous efficiency of the light-emitting diode.

[0029] In one embodiment, the first type of reflective layer can be divided into three groups: a first substructure layer, a second substructure layer, and a third substructure layer. Specifically, the three groups of substructure layers can be formed by growing aluminum gallium arsenide (AlGaAs). The material of the first reflective sublayer may include Al x1 Ga 1-x1 As, the material of the second reflective sublayer includes Al. x2 Ga 1-x2As, where x1 ranges from 0.5 to 0.55, and x2 ranges from 0.9 to 0.95. A first and second reflective sublayer can be combined to form a cycle pair, and this cycle pair can be grown periodically to sequentially obtain a first substructure layer, a second substructure layer, and a third substructure layer. The growth thickness of each cycle pair in the three substructure layers is different. The growth thickness of the first and second sub-reflective layers in the first substructure layer is between 45nm and 55nm; the growth thickness of the first and second sub-reflective layers in the second substructure layer is between 40nm and 50nm; and the growth thickness of the first and second sub-reflective layers in the third substructure layer is between 35nm and 45nm. The Al component in each cycle pair in the first, second, and third substructure layers is the same, meaning the proportion of Al component in each cycle pair is the same. For example, the proportion of Al component in the cycle pair is 40%, but the specific Al component proportion can be configured and adjusted according to actual application requirements. During the growth of the first, second, and third substructure layers, each substructure layer can be doped separately. Magnesium can be used as the doping element for all three substructure layers, with a doping concentration between 9 x 10⁻⁶. 17 cm -3 Up to 2x10 18 cm -3 The number of cycle pairs in the three sub-structure layers can also be set according to actual application requirements. For example, the first sub-structure layer can be formed by periodically stacking 3 to 8 cycle pairs, the second sub-structure layer can also be formed by periodically stacking 3 to 8 cycle pairs, and the third sub-structure layer can be formed by periodically stacking 17 to 22 cycle pairs. Of course, the number of sub-structure layers in the first type of reflective layer can also be adjusted according to actual application requirements, and there is no limitation here. By designing different thicknesses and compositions of sub-structure layers in the first type of reflective layer, the reflectivity of multi-quantum-well light sources can be effectively improved, thereby improving luminous efficiency.

[0030] Please see Figure 3 , Figure 3 This application provides a method for fabricating a light-emitting diode epitaxial structure, which includes the following steps:

[0031] Step S300: Provide a substrate; gallium arsenide (GaAs) can be used as the substrate to grow an epitaxial structure on the gallium arsenide substrate.

[0032] Step S310: An epitaxial structure is fabricated on the substrate. This epitaxial structure includes a first-type semiconductor layer 101, a light-emitting layer 102, and a second-type semiconductor layer 103. The light-emitting layer 102 may be disposed on one side of the first-type semiconductor layer 101, and the second-type semiconductor layer 103 may be disposed on the side of the light-emitting layer 102 opposite to the first-type semiconductor layer 101. The first-type semiconductor layer 101 includes a first-type ohmic contact layer and an arsenide-based first-type reflective layer. The first-type reflective layer is disposed between the first-type ohmic contact layer and the light-emitting layer 102, and it spreads current through the first-type ohmic contact layer and reflects light from the light-emitting layer 102.

[0033] In one embodiment, the first type can be P-type, and the second type can be N-type. The first type semiconductor layer 101 may include a P-type buffer layer 1011, a P-type etching stop layer 1012, a P-type ohmic contact layer 1013, a P-type reflective layer 1014, a P-type confinement layer 1015, and a P-type waveguide layer 1016. The light-emitting layer 102 may employ a multi-quantum-well structure as a light source. The second type semiconductor layer 103 includes an N-type waveguide layer 1031, an N-type confinement layer 1032, and an N-type window layer 1033. The P-type buffer layer 1011 may be made of gallium arsenide (GaAs), the P-type etching stop layer 1012 may be made of gallium phosphide (GaP), the P-type ohmic contact layer 1013 may be made of gallium arsenide (GaAs), the P-type confinement layer 1015 and the N-type confinement layer 1032 may both be made of aluminum indium phosphide (AlInP), the N-type window layer 1033 may be made of gallium phosphide (GaP), and the P-type reflective layer 1014 may be made of an arsenide-based material. Specifically, a P-type buffer layer 1011, a P-type etch stop layer 1012, a P-type ohmic contact layer 1013, a P-type reflective layer 1014, a P-type confinement layer 1015, a P-type waveguide layer 1016, a light-emitting layer 102, an N-type waveguide layer 1031, an N-type confinement layer 1032, and an N-type window layer 1033 can be sequentially grown on a gallium arsenide substrate. Traditional LED epitaxial layer structures typically first dope with an N-type dopant source to form an N-type semiconductor layer, then grow a multi-quantum-well light-emitting layer 102, and finally dope with a P-type dopant source to form a P-type semiconductor layer. This N-type dopant source is typically silane or disilane. The LED epitaxial structure of this application differs from existing epitaxial structures in that it preferentially grows a P-type doped P-type semiconductor layer on a gallium arsenide substrate, and finally grows an N-type doped N-type semiconductor layer. By inverting the doping, the chip manufacturing process can be shortened, and production efficiency improved.

[0034] In one embodiment, the fabrication process of the first type of reflective layer includes: setting the temperature of the reaction chamber to 650-670°C and the pressure to 50 mbar; introducing arsine as a group V source, hydrogen as a carrier gas, and trimethylaluminum and trimethylgallium as group III sources onto the first type of ohmic contact layer to form a first type of reflective layer composed of multiple sub-structure layers. Each sub-structure layer includes multiple sets of loop pairs, and each set of loop pairs is formed by stacking a first reflective sub-layer and a second reflective sub-layer. Specifically, the number of sub-structure layers in the first type of reflective layer can be set and adjusted according to actual application requirements, and is not limited here. Taking a first type of reflective layer containing three sub-structure layers as an example, the fabrication method of this first type of reflective layer includes the following steps.

[0035] Fabrication of the first substructure layer: AlGaAs and a first reflective sublayer are alternately grown on a p-type GaAs substrate. The first and second reflective sublayers form a cycle pair. Multiple cycle pairs are grown periodically to obtain the first substructure layer. Key process conditions: Temperature set at 650-670℃, chamber pressure at 50 mbar, using arsine as a Group V source, hydrogen as the carrier gas, and introducing a certain amount of trimethylaluminum and trimethylgallium as Group III sources. The amount of trimethylaluminum and trimethylgallium as Group III sources can be adjusted according to actual composition requirements and is not limited here. The growth material of the first substructure layer is AlGaAs; specifically, the material of the first reflective sublayer is Al... x1 Ga 1-x1 As, the material of the second reflective sublayer is Al. x2 Ga 1-x2 As, where x1 ranges from 0.5 to 0.55, and x2 ranges from 0.9 to 0.95. The growth thickness of the first reflective sublayer is 45-55 nm, and the growth thickness of the second reflective sublayer can also be set to 45-55 nm. During the alternating growth of the first and second reflective sublayers, magnesia-dicero is used as the doping source to dope each sublayer, with a doping concentration of 9 x 10⁻⁶. 17 cm -3 Up to 2x10 18 cm -3 The doping element is magnesium. The cycle pairs consisting of the first reflective sublayer and the second reflective sublayer are repeatedly grown in 3 to 8 pairs. The Al composition of each cycle pair in the first substructure layer is the same, that is, the Al composition ratio in each cycle pair is the same. For example, the Al composition ratio can be configured to 50%. The specific Al composition ratio can be configured and adjusted according to the actual application requirements, and there is no limitation here.

[0036] Fabrication of the second substructure layer: The same amount of trimethylaluminum and trimethylgallium as during the growth of the first substructure layer is introduced. The first and second reflective sublayers are grown sequentially as a cycle pair. The growth thickness range of the first and second reflective sublayers in the second substructure layer differs from that of the first substructure layer. Specifically, the growth thickness of both the first and second reflective sublayers in the second substructure layer can be set to 40-50 nm. Magnesium diacene is used as the doping source, with magnesium as the dopant element and a doping concentration of 9 x 10⁻⁶. 17 cm -3 Up to 2x10 18 cm -3 The cycle pairs consisting of the first reflective sublayer and the second reflective sublayer are repeatedly grown in 3 to 8 pairs. The Al component of each cycle pair in the second substructure layer is the same, that is, the proportion of Al component in each cycle pair is the same. For example, the proportion of Al component can be configured to 60%. The specific proportion of Al component can be configured and adjusted according to the actual application requirements, and there is no limitation here.

[0037] Fabrication of the third substructure layer: The same amount of trimethylaluminum and trimethylgallium as used in the growth of the second substructure layer is introduced. The first and second reflective sublayers are grown sequentially as a cycle pair. The growth thickness ranges of the first and second reflective sublayers of the third substructure layer differ from those of the first and second reflective sublayers of the second substructure layer. Specifically, the growth thicknesses of both the first and second reflective sublayers of the third substructure layer can be set to 35-45 nm. Magnesium diacene is used as the dopant source, with magnesium as the dopant element and a doping concentration of 9 x 10⁻⁶. 17 cm -3 Up to 2x10 18 cm -3 The cycle pairs consisting of the first reflective sublayer and the second reflective sublayer are repeatedly grown in 17 to 22 pairs. The Al component of each cycle pair in the third substructure layer is the same, that is, the proportion of Al component in each cycle pair is the same. For example, the proportion of Al component can be configured to 60%. The specific proportion of Al component can be configured and adjusted according to the actual application requirements, and there is no limitation here.

[0038] After completing the growth of the first substructure layer, the second substructure layer and the third substructure layer, the p-type AlInP confinement layer, the p-type waveguide layer 1016, the light-emitting layer 102, the N-type waveguide layer 1031, the n-type AlInP confinement layer and the N-type window layer 1033 are grown sequentially.

[0039] Based on the epitaxial structure fabrication method of the embodiments of this application above, replacing the traditional AlGaInP current spreading layer with an arsenide-based P-type reflective layer 1014 not only serves the purpose of current spreading but also enhances luminous efficiency and increases the brightness of a single light-emitting diode by reflecting light from a multi-quantum-well source. With the brightness of a single light-emitting diode improved, matrixing multiple light-emitting diodes can increase the overall brightness, thereby significantly lowering the matrixing threshold and improving production efficiency. By inverting the doping process, first doping with a P-type dopant source and then with an N-type dopant source, it is beneficial to shorten the chip manufacturing process and improve production efficiency.

[0040] Please see Figure 4 , Figure 4 This is a schematic diagram of a light-emitting diode (LED) according to an embodiment of this application. The LED includes an epitaxial structure, a first electrode 104, and a second electrode 105. The epitaxial structure includes a first-type semiconductor layer 101, a light-emitting layer 102, and a second-type semiconductor layer 103. The light-emitting layer 102 may be disposed on one side of the first-type semiconductor layer 101, and the second-type semiconductor layer 103 may be disposed on the side of the light-emitting layer 102 opposite to the first-type semiconductor layer 101. The first-type semiconductor layer 101 includes a first-type ohmic contact layer and an arsenide-based first-type reflective layer. The first-type reflective layer is disposed between the first-type ohmic contact layer and the light-emitting layer 102, and it spreads the current through the first-type ohmic contact layer and reflects the light from the light-emitting layer 102. The first electrode 104 may be electrically connected to the first-type ohmic contact layer in the first-type semiconductor layer 101, and the second electrode 105 may be electrically connected to the second-type semiconductor layer 103.

[0041] In one embodiment, the first type can be P-type, and the second type can be N-type. The first type semiconductor layer 101 may include a P-type buffer layer 1011, a P-type etch stop layer 1012, a P-type ohmic contact layer 1013, a P-type reflective layer 1014, a P-type confinement layer 1015, and a P-type waveguide layer 1016 stacked sequentially. The light-emitting layer 102 may employ a multi-quantum-well structure as a light source. The second type semiconductor layer 103 includes an N-type waveguide layer 1031, an N-type confinement layer 1032, and an N-type window layer 1033 stacked sequentially, wherein the P-type waveguide layer 1016 and the N-type waveguide layer 1031 are respectively disposed on opposite sides of the light-emitting layer 102. The material of the P-type buffer layer 1011 can be gallium arsenide (GaAs), the material of the P-type corrosion cutoff layer 1012 can be GaP, the material of the P-type ohmic contact layer 1013 can be gallium arsenide, the materials of the P-type confinement layer 1015 and the N-type confinement layer 1032 can both be aluminum indium phosphide (AlInP), the N-type window layer 1033 can be gallium phosphide, and the P-type reflective layer 1014 can be an arsenide-based material.

[0042] In one embodiment, the first electrode 104 can be a P-electrode, and the second electrode 105 can be an N-electrode. The first electrode 104 is disposed on the side of the P-type ohmic contact layer 1013 away from the P-type corrosion stop layer 1012, and the second electrode 105 is disposed on the side of the N-type window layer 1033 away from the N-type confinement layer 1032.

[0043] The first type of reflective layer may include multiple sub-structure layers, each sub-structure layer including multiple sets of loop pairs, each set of loop pairs being obtained by stacking the first reflective sub-layer and the second reflective sub-layer.

[0044] In one embodiment, the first type of reflective layer can be divided into three groups: a first substructure layer, a second substructure layer, and a third substructure layer. Specifically, the three groups of substructure layers can be formed by growing aluminum gallium arsenide (AlGaAs). The material of the first reflective sublayer may include Al x1 Ga 1-x1 As, the material of the second reflective sublayer includes Al. x2 Ga 1-x2 As, where x1 ranges from 0.5 to 0.55, and x2 ranges from 0.9 to 0.95. A first and second reflective sublayer can be combined to form a cycle pair, and this cycle pair can be grown periodically to sequentially obtain a first substructure layer, a second substructure layer, and a third substructure layer. The growth thickness of each cycle pair in the three substructure layers is different: the growth thickness of the first and second subreflective layers in the first substructure layer is between 45 nm and 55 nm; the growth thickness of the first and second subreflective layers in the second substructure layer is between 40 nm and 50 nm; and the growth thickness of the first and second subreflective layers in the third substructure layer is between 35 nm and 45 nm. The Al component in each cycle pair in the first, second, and third substructure layers is the same, meaning the proportion of Al component in each cycle pair is the same. For example, the proportion of Al component in the cycle pair is 40%, but the specific Al component proportion can be configured and adjusted according to actual application requirements. During the growth of the first, second, and third substructure layers, each substructure layer can be doped separately. Magnesium can be used as the doping element for all three substructure layers, with a doping concentration between 9 x 10⁻⁶. 17 cm -3 Up to 2x10 18 cm -3The number of cycle pairs in the three sub-structure layers can also be set according to actual application requirements. For example, the first sub-structure layer can be formed by periodically stacking 3 to 8 cycle pairs, the second sub-structure layer can also be formed by periodically stacking 3 to 8 cycle pairs, and the third sub-structure layer can be formed by periodically stacking 17 to 22 cycle pairs. Of course, the number of sub-structure layers in the first type of reflective layer can also be adjusted according to actual application requirements, and there is no limitation here. By designing different thicknesses and compositions of sub-structure layers in the first type of reflective layer, the reflectivity of multi-quantum-well light sources can be effectively improved, thereby improving luminous efficiency.

[0045] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A light emitting diode epitaxial structure, comprising: The application relates to a semiconductor structure and a method for manufacturing the semiconductor structure. The semiconductor structure comprises: a first type semiconductor layer; a light emitting layer arranged on one side of the first type semiconductor layer; and a second type semiconductor layer arranged on the side of the light emitting layer away from the first type semiconductor layer; wherein the first type semiconductor layer comprises a first type ohmic contact layer and a first type reflection layer of an arsenic system, the first type reflection layer is arranged between the first type ohmic contact layer and the light emitting layer, the first type reflection layer is used for current spreading of the first type ohmic contact layer and reflection of light of the light emitting layer; the first type reflection layer comprises a plurality of substructure layers, each of the substructure layers comprises a plurality of cyclic pairs, each of the cyclic pairs is obtained by stacking a first reflection sublayer and a second reflection sublayer; the material of the first reflection sublayer comprises Alx1Ga1-x1As, the material of the second reflection sublayer comprises Alx2Ga1-x2As, wherein the value range of x1 is between 0.5 and 0.55, and the value range of x2 is between 0.9 and 0.

95.

2. The light emitting diode epitaxial structure of claim 1, wherein, The Al components of each of the cyclic pairs are the same.

3. The light emitting diode epitaxial structure of claim 1, wherein, The first type reflection layer comprises a first substructure layer, a second substructure layer and a third substructure layer stacked in sequence towards the light emitting layer, the doping concentration range and the doping element of the first substructure layer, the second substructure layer and the third substructure layer are the same.

4. The light emitting diode epitaxial structure of claim 3, wherein, The doping element comprises magnesium, the doping concentration range is between 9x1017 cm-3 and 2x1018 cm-3, the growth thickness of the first reflection sublayer and the second reflection sublayer of the first substructure layer is between 45 nm and 55 nm, the growth thickness of the first reflection sublayer and the second reflection sublayer of the second substructure layer is between 40 nm and 50 nm, and the growth thickness of the first reflection sublayer and the second reflection sublayer of the third substructure layer is between 35 nm and 45 nm.

5. The light emitting diode epitaxial structure of claim 4, wherein, The number of cyclic pairs of the first substructure layer is between 3 and 8 pairs, the number of cyclic pairs of the second substructure layer is between 3 and 8 pairs, and the number of cyclic pairs of the third substructure layer is between 17 and 22 pairs.

6. A method for fabricating a light-emitting diode epitaxial structure, characterized in that, The method comprises: providing a substrate; manufacturing an epitaxial structure on the substrate, the epitaxial structure comprises: a first type semiconductor layer arranged on one side of the substrate; a light emitting layer arranged on one side of the first type semiconductor layer; and a second type semiconductor layer arranged on the side of the light emitting layer away from the first type semiconductor layer; wherein the first type semiconductor layer comprises a first type ohmic contact layer and a first type reflection layer formed by stacking a plurality of arsenic system semiconductor layers, the first type reflection layer is arranged between the first type ohmic contact layer and the light emitting layer, the first type reflection layer is used for current spreading of the first type ohmic contact layer and reflection of light of the light emitting layer; The first type of reflective layer includes a plurality of substructure layers, each of the substructure layers includes a plurality of cyclic pairs, each of the cyclic pairs is stacked by a first reflective sublayer and a second reflective sublayer; the material of the first reflective sublayer includes Alx1Ga1-x1As, and the material of the second reflective sublayer includes Alx2Ga1-x2As, wherein the value range of x1 is between 0.5 and 0.55, and the value range of x2 is between 0.9 and 0.

95.

7. The method of claim 6, wherein the method further comprises: The preparation process of the first type of reflective layer includes: The temperature of the reaction cavity is set to 650-670 ℃, the pressure is 50 mbar, arsine is introduced as a group V source, hydrogen is introduced as a carrier gas, and trimethylaluminum and trimethylgallium are introduced as group III sources on the first type of ohmic contact layer to form the first type of reflective layer composed of a plurality of substructure layers, wherein each of the substructure layers includes a plurality of cyclic pairs, each of the cyclic pairs is stacked by a first reflective sublayer and a second reflective sublayer.

8. A light emitting diode, comprising: The preparation process of the first type of reflective layer includes: An epitaxial structure includes: a first type of semiconductor layer; a light-emitting layer arranged on one side of the first type of semiconductor layer; and a second type of semiconductor layer arranged on the side of the light-emitting layer away from the first type of semiconductor layer; wherein the first type of semiconductor layer includes a first type of ohmic contact layer and an arsenic-based first type of reflective layer, the first type of reflective layer is arranged between the first type of ohmic contact layer and the light-emitting layer, the first type of reflective layer is used for current spreading of the first type of ohmic contact layer and reflecting light of the light-emitting layer; the first type of reflective layer includes a plurality of substructure layers, each of the substructure layers includes a plurality of cyclic pairs, each of the cyclic pairs is stacked by a first reflective sublayer and a second reflective sublayer; the material of the first reflective sublayer includes Alx1Ga1-x1As, and the material of the second reflective sublayer includes Alx2Ga1-x2As, wherein the value range of x1 is between 0.5 and 0.55, and the value range of x2 is between 0.9 and 0.95; a first electrode electrically connected with the first type of ohmic contact layer; a second electrode electrically connected with the second type of semiconductor layer.

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