阅读说明：本技术 嵌套金刚石散热层的纳米柱led结构及制备方法 (Nano-column LED structure with nested diamond heat dissipation layer and preparation method ) 是由 许晟瑞 赵颖 马凯立 彭若诗 范晓萌 杜金娟 张雅超 张金风 张进成 郝跃 于 2021-05-19 设计创作，主要内容包括：本发明涉及一种嵌套金刚石散热层的纳米柱LED结构及制备方法,该纳米柱LED结构包括：衬底层；成核层,位于衬底层上；第一n型掺杂GaN层,位于成核层上；键合层,间隔分布在第一n型掺杂GaN层上；金刚石层,位于键合层上；若干纳米柱LED结构,位于第一n型掺杂GaN层上,且每个纳米柱LED结构均嵌套于金刚石层和键合层中；若干第一电极,位于第一n型掺杂GaN层上,且位于金刚石层之间,若干第一电极与若干纳米柱LED结构一一对应；若干第二电极,一一对应的设置在纳米柱LED结构上。该纳米柱LED结构将纳米柱LED结构嵌套于金刚石层中,同时解决了器件的散热问题和出光问题,提高了器件的性能。(The invention relates to a nano-pillar LED structure nested with a diamond heat dissipation layer and a preparation method thereof, wherein the nano-pillar LED structure comprises: a substrate layer; a nucleation layer on the substrate layer; the first n-type doped GaN layer is positioned on the nucleating layer; the bonding layers are distributed on the first n-type doped GaN layer at intervals; the diamond layer is positioned on the bonding layer; the nano-pillar LED structures are positioned on the first n-type doped GaN layer, and each nano-pillar LED structure is nested in the diamond layer and the bonding layer; the plurality of first electrodes are positioned on the first n-type doped GaN layer and positioned between the diamond layers, and the plurality of first electrodes correspond to the plurality of nano-pillar LED structures one to one; and the second electrodes are correspondingly arranged on the nano-pillar LED structures one by one. According to the nano-column LED structure, the nano-column LED structure is nested in the diamond layer, the heat dissipation problem and the light emitting problem of a device are solved, and the performance of the device is improved.)

1. A nano-pillar LED structure with a nested diamond heat dissipation layer, comprising:

a substrate layer (1);

a nucleation layer (2) located on the substrate layer (1);

a first n-doped GaN layer (3) on the nucleation layer (2);

bonding layers (4) distributed at intervals on the first n-type doped GaN layer (3);

a diamond layer (5) on the bonding layer (4);

a plurality of nano-pillar LED structures (6) located on the first n-type doped GaN layer (3), and each nano-pillar LED structure (6) is nested in the diamond layer (5) and the bonding layer (4);

a plurality of first electrodes (7) located on the first n-type doped GaN layer (3) and between the diamond layers (5), the plurality of first electrodes (7) corresponding to the plurality of nano-pillar LED structures (6) one to one;

and the second electrodes (8) are correspondingly arranged on the nano-pillar LED structures (6) one by one.

2. The nano-pillar LED structure of a nested diamond heat spreading layer according to claim 1, wherein the material of the nucleation layer (2) comprises AlN with a thickness of 10-70 nm.

3. The nano-pillar LED structure of a nested diamond heat dissipation layer according to claim 1, wherein the thickness of the first n-type doped GaN layer (3) is 100-2500 nm.

4. The nested diamond heat spreading layer nano-pillar LED structure according to claim 1, wherein the thickness of the diamond layer (5) is equal to the height of the nano-pillar LED structure (6).

5. The nano-pillar LED structure of the nested diamond heat dissipation layer as recited in claim 1, wherein the thickness of the diamond layers (5) is 500-3000 nm, and the distance between the adjacent diamond layers (5) is 1-20 μm.

6. The nano-pillar LED structure of a nested diamond heat dissipation layer according to claim 1, wherein the height of the nano-pillar LED structure (6) is 500-3000 nm, and the distance between adjacent nano-pillar LED structures (6) is 1-100 μm.

7. The nested diamond heat spreading layer nanopillar LED structure according to claim 1, wherein the nanopillar LED structure (6) comprises a second n-type doped GaN layer (61), a quantum well layer (62), an electron blocking layer (63), and a p-type doped GaN layer (64), wherein,

the second n-type doped GaN layer (61) is located on the first n-type doped GaN layer (3), the quantum well layer (62) is located on the second n-type doped GaN layer (61), the electron blocking layer (63) is located on the quantum well layer (62), and the p-type doped GaN layer (64) is located on the electron blocking layer (63).

8. The nested diamond heat spreading layer nano-pillar LED structure according to claim 7, wherein the material of the well layers in the quantum well layers (62) comprises one or more of GaN, InGaN, AlGaN.

9. A preparation method of a nano-pillar LED structure of a nested diamond heat dissipation layer is characterized by comprising the following steps:

growing a nucleation layer (2) on the substrate layer (1);

growing a first n-doped GaN layer (3) on the nucleation layer (2);

bonding alloy diamond on the first n-type doped GaN layer (3) to form a bonding layer (4) and a diamond layer (5);

etching the bonding layer (4) and the diamond layer (5) until the first n-type doped GaN layer (3) to form a plurality of nano holes (60), and growing nano-column LED structures (6) in the nano holes (60);

etching the bonding layer (4) and the diamond layer (5) around the nano-pillar LED structure (6) until the first n-type doped GaN layer (3) to form a plurality of grooves (71), preparing a first electrode (7) in the grooves (71), and preparing a second electrode (8) on the nano-pillar LED structure (6).

10. The method for preparing a nano-pillar LED structure with a nested diamond heat dissipation layer according to claim 9, wherein an alloy diamond is bonded on the first n-type doped GaN layer (3) to form a bonding layer (4) and a diamond layer (5), and the method comprises the following steps:

bonding materials are respectively prepared on the surface of the diamond and the first n-type doped GaN layer (3);

bonding the diamond with the first n-doped GaN layer (3) using the bonding material, forming the bonding layer (4) and the diamond layer (5).

Technical Field

The invention belongs to the technical field of microelectronic devices, and particularly relates to a nano-pillar LED structure with a diamond heat dissipation layer nested and a preparation method of the nano-pillar LED structure.

Background

Nitride Light Emitting Diodes (LEDs) are the most attractive new generation of lighting technology due to their advantages of high efficiency, long life, energy saving, environmental protection, etc. In addition, the III group nitride semiconductor materials are direct band gap semiconductors with wide forbidden bands, and various ternary or quaternary alloys can be formed by adjusting the proportion of components in the materials, so that the forbidden band width can be continuously changed between 0.7eV and 6.2eV, and the light-emitting waveband covers the waveband range from infrared to extreme ultraviolet. Thus, group iii nitride semiconductor materials are the most commonly used materials for making LEDs, such as AlN-based, GaN-based, InN-based, and ternary alloys thereof.

However, with the development of technology, LED devices based on nitride semiconductor materials tend to be smaller and have higher output power, and the importance of "heat dissipation" becomes more and more prominent, and becomes one of the most important issues restricting the nitride devices to higher performance.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a nano-pillar LED structure with a nested diamond heat dissipation layer and a preparation method thereof. The technical problem to be solved by the invention is realized by the following technical scheme:

the embodiment of the invention provides a nano-pillar LED structure of a nested diamond heat dissipation layer, which comprises:

a substrate layer;

a nucleation layer on the substrate layer;

a first n-type doped GaN layer on the nucleation layer;

the bonding layers are distributed on the first n-type doped GaN layer at intervals;

a diamond layer on the bonding layer;

a plurality of nano-pillar LED structures located on the first n-type doped GaN layer, each of the nano-pillar LED structures nested in the diamond layer and the bonding layer;

the plurality of first electrodes are positioned on the first n-type doped GaN layer and between the diamond layers, and the plurality of first electrodes correspond to the plurality of nano-pillar LED structures one to one;

and the plurality of second electrodes are correspondingly arranged on the nano-pillar LED structures one by one.

In one embodiment of the invention, the material of the nucleation layer comprises AlN and has a thickness of 10-70 nm.

In one embodiment of the present invention, the thickness of the first n-type doped GaN layer is 100 to 2500 nm.

In one embodiment of the invention, the thickness of the diamond layer is equal to the height of the nanopillar LED structure.

In one embodiment of the present invention, the thickness of the diamond layers is 500 to 3000nm, and the distance between adjacent diamond layers is 1 to 20 μm.

In one embodiment of the invention, the height of the nano-pillar LED structure is 500-3000 nm, and the distance between adjacent nano-pillar LED structures is 1-100 μm.

In one embodiment of the present invention, the nanorod LED structure includes a second n-type doped GaN layer, a quantum well layer, an electron blocking layer, and a p-type doped GaN layer, wherein,

the second n-type doped GaN layer is located on the first n-type doped GaN layer, the quantum well layer is located on the second n-type doped GaN layer, the electronic barrier layer is located on the quantum well layer, and the p-type doped GaN layer is located on the electronic barrier layer.

In one embodiment of the invention, the material of the well layers in the quantum well layer comprises one or more of GaN, InGaN, and AlGaN.

Another embodiment of the present invention provides a method for manufacturing a nano-pillar LED structure with a diamond heat dissipation layer embedded therein, including the steps of:

growing a nucleation layer on the substrate layer;

growing a first n-type doped GaN layer on the nucleation layer;

bonding alloy diamond on the first n-type doped GaN layer to form a bonding layer and a diamond layer;

etching the bonding layer and the diamond layer until the first n-type doped GaN layer forms a plurality of nano holes, and growing nano-pillar LED structures in the nano holes;

and etching the bonding layer and the diamond layer around the nano-pillar LED structure until the first n-type doped GaN layer forms a plurality of grooves, preparing a first electrode in the grooves, and preparing a second electrode on the nano-pillar LED structure.

In one embodiment of the present invention, bonding diamond on the first n-type doped GaN layer to form a bonding layer and a diamond layer includes:

preparing bonding materials on the surface of the diamond and the first n-type doped GaN layer respectively;

and bonding the diamond and the first n-type doped GaN layer by using the bonding material to form the bonding layer and the diamond layer.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, the nano-pillar LED structure is nested in the diamond layer, the self-heating effect of the device during working can be relieved due to the high thermal conductivity of the diamond, the self-heat dissipation problem of the nitride semiconductor is solved, the heat dissipation efficiency of the device is improved, meanwhile, the forbidden bandwidth of the diamond is wide, the transmission spectrum from ultraviolet to far infrared can be transmitted, the light transmittance is good, the side wall light-emitting rate of the nano-pillar LED device can be increased, and the light-emitting efficiency of the device is improved.

Drawings

FIG. 1 is a schematic structural diagram of a nano-pillar LED structure with a nested diamond heat dissipation layer according to an embodiment of the present invention;

FIG. 2 is a schematic flow chart of a method for manufacturing a nano-pillar LED structure with a nested diamond heat dissipation layer according to an embodiment of the present invention;

fig. 3 a-3 h are schematic process diagrams of a manufacturing method of a nano-pillar LED structure with a nested diamond heat dissipation layer according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to specific examples, but the embodiments of the present invention are not limited thereto.

Example one

Referring to fig. 1, fig. 1 is a schematic structural diagram of a nano-pillar LED structure with a nested diamond heat dissipation layer according to an embodiment of the present invention. The nano-pillar LED structure comprises a substrate layer 1, a nucleating layer 2, a first n-type doped GaN layer 3, a bonding layer 4, a diamond layer 5, a plurality of nano-pillar LED structures 6, a plurality of first electrodes 7 and a plurality of second electrodes 8.

Wherein the material of the substrate layer 1 comprises c-plane Al₂O₃. The nucleation layer 2 is located on the substrate layer 1, and the material of the nucleation layer 2 comprises AlN, and can be a high-temperature AlN nucleation layer, and the thickness is 10-70 nm. The first n-type doped GaN layer 3 is located on the nucleating layer 2, and the material of the first n-type doped GaN layer 3 comprises n-GaN and has the thickness of 100-2500 nm. Bonding layer 4 is at interval distribution on first n type doping GaN layer 3, and the material of bonding layer 4 includes SiN, and thickness is 15 ~ 40 nm.

The diamond layer 5 is positioned on the bonding layer 4, the thickness of the diamond layer 5 is 500-3000 nm, and the distance d between every two adjacent diamond layers 5₁1 to 20 μm; it will be appreciated that the bonding layers 4 serve to bond the diamond layer 5 to the first n-doped GaN layer 3, and therefore the diamond layers 5 are also spaced apart with a spacing between adjacent bonding layers 4The distance of (a) is also 1 to 20 μm.

A number of nanopillar LED structures 6 are located on the first n-doped GaN layer 3, and each nanopillar LED structure is nested in the diamond layer 5 and the bonding layer 4. Specifically, a plurality of nano-pillar LED structures 6 are disposed on the first n-type doped GaN layer 3, the nano-pillar LED structures 6 are cylindrical, diamonds are disposed on the cylindrical side walls, the diamonds surround the nano-pillar LED structures 6, and the bonding layer 4 is used for bonding the diamond layer 5 and the first n-type doped GaN layer 3, so that the bonding layer 4 also surrounds the nano-pillar LED structures 6, which surround the bottoms of the nano-pillar LED structures 6. The height h of the nano-pillar LED structure 6 is 500-3000 nm, the diameter is 100-1000nm, and the distance d between the adjacent nano-pillar LED structures 6₂1 to 100 μm.

The first electrodes 7 are located on the first n-type doped GaN layer 3 and located between the diamond layers, and the first electrodes 7 correspond to the nano-pillar LED structures 6 one to one. Specifically, a groove is etched in the diamond on the side of the nano-pillar LED structure 6, the first electrode 7 is located in the groove, a structure in which the first electrode 7 is located between the diamond layers 5 is formed, and the first electrode 7 is spaced apart from the diamond layers 5 by a certain distance, that is, the first electrode 7 is not in contact with the diamond layers 5.

The plurality of second electrodes 8 are correspondingly arranged on the nano-pillar LED structure one by one.

In one embodiment, the first electrode 7 is an n-type electrode and the second electrode 8 is a p-type electrode.

Further, the thickness of the diamond layer 5 may be smaller than the height of the nano-pillar LED structure 6, may also be equal to the height of the nano-pillar LED structure 6, and may also be larger than the height of the nano-pillar LED structure 6; preferably, the thickness of the diamond layer 5 is equal to the height of the nano-pillar LED structure 6, under which the heat dissipation efficiency and the light emitting performance of the device can simultaneously achieve better performance.

In a particular embodiment, the nanorod LED structure 6 includes a second n-type doped GaN layer 61, a quantum well layer 62, an electron blocking layer 63, and a p-type doped GaN layer 64.

The second n-type doped GaN layer 61 is located on the first n-type doped GaN layer 3, and the material thereof includes n-GaN. The quantum well layer 62 is located on the second n-type doped GaN layer 61, and the quantum well layer 62 adopts a multi-quantum well, wherein the well layer material includes one or more of GaN, InGaN, and AlGaN. An electron blocking layer 63 is located on the quantum well layer 62, and its material includes AlGaN. A p-type doped GaN layer 64, the material of which comprises p-GaN, is located on the electron blocking layer 63.

In this embodiment, the quantum well adopts one or more of GaN, InGaN, and AlGaN materials as the light emitting layer, so that light emitting devices with different colors can be realized.

Because the diamond has higher thermal conductivity of 2200W/m.K, which is 4-5 times of that of SiC, when the diamond is used as the substrate of a GaN-based device, the self-heating effect of the GaN-based high-power device can be reduced, the problem that the power density is rapidly reduced due to the increase of the total power and the increase of the frequency is solved, the diamond is directly contacted with the side wall of the nano-pillar LED structure, the LED can be directly radiated, and the radiation efficiency is higher.

In addition, the forbidden band width of 5.5eV of the diamond is the widest of all solid materials, so that the transmission spectrum of the diamond can be transmitted from ultraviolet to far infrared, the diamond has good light transmission, the special performance and the inherent excellent characteristic of the diamond can prepare an excellent optical window material, and light generated by the nitride LED can not be absorbed, so that the side wall light-emitting rate of the nano-pillar LED device is increased, and the luminous efficiency of the device is improved.

To sum up, this embodiment is with the nested diamond layer of nano-column LED structure, has solved the heat dissipation problem and the light-emitting problem of device simultaneously, has improved the performance of device.

Example two

On the basis of the first embodiment, please refer to fig. 2 and fig. 3a to 3h, fig. 2 is a schematic flow chart of a method for manufacturing a nano-pillar LED structure of a nested diamond heat dissipation layer according to an embodiment of the present invention, and fig. 3a to 3h are schematic process diagrams of the method for manufacturing the nano-pillar LED structure of the nested diamond heat dissipation layer according to the embodiment of the present invention. The preparation method of the nano-pillar LED structure of the nested diamond heat dissipation layer comprises the following steps:

and S1, growing a nucleation layer 2 on the substrate layer 1.

Selecting C-surface Al₂O₃See fig. 3a for a substrate layer. First, the substrate layer 1 is heat-treated: mixing the c surface Al₂O₃The substrate is placed in a MOCVD reaction chamber for Metal-organic Chemical Vapor Deposition, the vacuum of the reaction chamber is reduced to less than 2X 10^-2Torr; and introducing hydrogen into the reaction chamber, heating the substrate to 900-1200 ℃ under the condition that the pressure of the MOCVD reaction chamber reaches 20-760 Torr, and keeping the temperature for 5-10 min to finish the heat treatment of the substrate.

Then, c-plane Al after heat treatment₂O₃And simultaneously introducing ammonia gas with the flow rate of 3000-4000 sccm and an aluminum source with the flow rate of 20-40 sccm into the substrate by adopting an MOCVD (metal organic chemical vapor deposition) process at the temperature of 950-1100 ℃ in the reaction chamber, and growing a high-temperature AlN nucleating layer 2 with the thickness of 10-70 nm under the condition of keeping the pressure of 20-760 Torr, as shown in FIG. 3 b.

S2, growing a first n-doped GaN layer 3 on the nucleation layer 2, see fig. 3 c.

And (3) adopting an MOCVD process on the AlN nucleating layer, keeping the temperature of an MOCVD reaction chamber at 950-1100 ℃, simultaneously introducing ammonia gas with the flow of 3000-4000 sccm, a gallium source with the flow of 20-40 sccm and a silicon source with the flow of 10-20 sccm, and growing a first n-type doped GaN layer 3 with the thickness of 100-2500 nm under the condition of keeping the pressure of 20-760 Torr.

S3, bonding diamond on the first n-type doped GaN layer 3 to form a bonding layer 4 and a diamond layer 5, as shown in fig. 3 d.

First, bonding materials are prepared on the diamond surface and the first n-type doped GaN layer 3, respectively. Specifically, a layer of SiN medium is deposited on the front surfaces of the diamond and the first n-type doped GaN layer 3 respectively by a chemical vapor deposition method to serve as a bonding material, and the thickness of the SiN medium is 15-40 nm.

Then, diamond is bonded to the first n-type doped GaN layer 3 using a bonding material, forming a bonding layer 4 and a diamond layer 5. Specifically, the diamond is placed into a reactive ion etching machine and activated by oxygen plasma, the cavity pressure is 50-150 mTor, the power is 300W, the oxygen flow is 10-100 sccm, then the first n-type doped GaN layer 3 and the front face of the diamond are bonded relatively at room temperature, bonding annealing is carried out for tens of hours at the temperature of 200 ℃, and the bonding layer 4 and the diamond layer 5 are formed.

S4, etching the bonding layer 4 and the diamond layer 5 until the first n-type doped GaN layer 3, forming a plurality of nanopores 60, and growing the nanopillar LED structures 6 in the plurality of nanopores 60.

A nanopore 60 is etched in the bonded diamond layer 5 down to the first n-doped GaN layer, see fig. 3 e; specifically, the shape of the nanopore 60 is circular, and the diameter of the circle is 100-1000 nm.

And then growing a second n-type doped GaN layer 61, a quantum well layer 62, an electron blocking layer 63 and a p-type doped GaN layer 64 with the total thickness of 1000-3000 nm by adopting an MOCVD (metal organic chemical vapor deposition) process in the etched place, namely the nanopore, of the diamond layer 5 to form the nanorod LED structure 6, as shown in fig. 3 f.

S5, etching the diamond layer 5 and the bonding layer 4 around the nano-pillar LED structure 6 until the first n-type doped GaN layer 3, forming a plurality of grooves 71, preparing first electrodes 7 in the grooves 71, and preparing second electrodes 8 on the nano-pillar LED structure 6.

And etching the diamond layer 5 and the bonding layer 4 around the nano-pillars by adopting a photoetching process until the first n-type doped GaN layer 3 is formed, forming a plurality of grooves 71, referring to fig. 3g, depositing n-type electrodes on the first n-type doped GaN layer 3 in the grooves 71 respectively by using a metal sputtering method, depositing p-type electrodes on the p-type doped GaN layer 63 at the top layer, referring to fig. 3h, and finishing the manufacture of the device.

EXAMPLE III

On the basis of the first embodiment and the second embodiment, please refer to fig. 2 and fig. 3a to fig. 3h, and the present embodiment describes a method for manufacturing an ultraviolet nanorod LED structure nested in a diamond layer. The preparation method comprises the following steps:

and S1, growing a nucleation layer 2 on the substrate layer 1.

Selecting C-surface Al₂O₃As a backing layer. First, the substrate layer 1 is heat-treated: mixing the c surface Al₂O₃Placing the substrate in MOCVD reaction chamber, and reducing the vacuum degree of the reaction chamber to less than 2 × 10^-2Torr; and introducing hydrogen into the reaction chamber, heating the substrate to 900 ℃ under the condition that the pressure of the MOCVD reaction chamber reaches 20Torr, and keeping the temperature for 5min to finish the heat treatment of the substrate.

Then, c-plane Al after heat treatment₂O₃On the substrate, an MOCVD process is adopted, under the condition that the temperature of a reaction chamber is 950 ℃, ammonia gas with the flow rate of 3000sccm and an aluminum source with the flow rate of 20sccm are simultaneously introduced, and a high-temperature AlN nucleating layer 2 with the thickness of 10nm is grown under the condition that the pressure is kept at 20 Torr.

S2, growing a first n-type doped GaN layer 3 on the nucleation layer 2.

And (3) adopting an MOCVD process on the AlN nucleating layer, keeping the temperature of an MOCVD reaction chamber at 950 ℃, simultaneously introducing ammonia gas with the flow of 3000sccm, a gallium source with the flow of 20sccm and a silicon source with the flow of 10sccm, and growing a first n-type doped GaN layer 3 with the thickness of 100nm under the condition of keeping the pressure of 20 Torr.

S3, bonding alloy diamond on the first n-type doped GaN layer 3, forming the bonding layer 4 and the diamond layer 5.

First, bonding materials are prepared on the diamond surface and the first n-type doped GaN layer 3, respectively. Specifically, a layer of SiN dielectric is deposited as a bonding material on the front surfaces of the diamond and the first n-type doped GaN layer 3 by a chemical vapor deposition method, and the thickness of the SiN dielectric is 15 nm.

Then, diamond is bonded to the first n-type doped GaN layer 3 using a bonding material, forming a bonding layer 4 and a diamond layer 5. Specifically, the diamond is placed into a reactive ion etcher and activated by oxygen plasma, the cavity pressure is 50mTor, the power is 300W, the oxygen flow is 10sccm, then the first n-type doped GaN layer 3 and the front surface of the diamond are bonded relatively at room temperature, and bonding annealing is carried out for ten hours at 200 ℃ to form the bonding layer 4 and the diamond layer 5.

S4, etching the bonding layer 4 and the diamond layer 5 until the first n-type doped GaN layer 3, forming a plurality of nanopores 60, and growing the nanopillar LED structures 6 in the plurality of nanopores 60.

Etching the diamond layer 5 by adopting a photoetching process until the nano holes 60 of the first n-type doped GaN layer are formed, and then growing an n-GaN layer 61 and a GaN/Al layer in sequence from bottom to top in the etched places, namely the nano holes, of the diamond layer 5 by adopting an MOCVD process_0.1Ga_0.9An N MQWs layer 62, an AlGaN layer 63 and a p-GaN layer 64 forming the nanorod LED structure 6.

S5, etching the diamond layer 5 and the bonding layer 4 around the nano-pillar LED structure 6 until the first n-type doped GaN layer 3, forming a plurality of grooves 71, preparing first electrodes 7 in the grooves 71, and preparing second electrodes 8 on the nano-pillar LED structure 6.

And etching the diamond layer 5 and the bonding layer 4 around the nano-pillar by adopting a photoetching process until the first n-type doped GaN layer 3 is reached to form a plurality of grooves 71, then respectively depositing n-type electrodes on the first n-type doped GaN layer 3 in the grooves 71 by using a metal sputtering method, and depositing p-type electrodes on the p-type doped GaN layer 64 at the top layer to finish the manufacture of the ultraviolet LED device.

Example four

Referring to fig. 2 and fig. 3a to fig. 3h, a method for fabricating a blue nanorod LED structure nested in a diamond layer is described in this embodiment. The preparation method comprises the following steps:

and S1, growing a nucleation layer 2 on the substrate layer 1.

Selecting C-surface Al₂O₃As a backing layer. First, the substrate layer 1 is heat-treated: mixing the c surface Al₂O₃Placing the substrate in MOCVD reaction chamber, and reducing the vacuum degree of the reaction chamber to less than 2 × 10^-2Torr; and introducing hydrogen into the reaction chamber, heating the substrate to 1000 ℃ under the condition that the pressure of the MOCVD reaction chamber reaches 200Torr, and keeping the temperature for 7min to finish the heat treatment of the substrate.

Then, c-plane Al after heat treatment₂O₃On the substrate, adopting MOCVD process under the condition of that the temperature of reaction chamber is 1000 deg.C, simultaneously introducing ammonia gas whose flow rate is 3500sccm and aluminium source whose flow rate is 30sccm into the reaction chamberThe high temperature AlN nucleation layer 2 was grown to a thickness of 50nm while maintaining a pressure of 50 Torr.

S2, growing a first n-type doped GaN layer 3 on the nucleation layer 2.

And (3) adopting an MOCVD process on the AlN nucleating layer, keeping the temperature of an MOCVD reaction chamber at 950 ℃, simultaneously introducing ammonia gas with the flow rate of 3500sccm, a gallium source with the flow rate of 30sccm and a silicon source with the flow rate of 20sccm, and growing a first n-type doped GaN layer 3 with the thickness of 1000nm under the condition of keeping the pressure of 50 Torr.

S3, bonding alloy diamond on the first n-type doped GaN layer 3, forming the bonding layer 4 and the diamond layer 5.

First, bonding materials are prepared on the diamond surface and the first n-type doped GaN layer 3, respectively. Specifically, a layer of SiN dielectric is deposited as a bonding material on the front surfaces of the diamond and the first n-type doped GaN layer 3 by a chemical vapor deposition method, and the thickness of the SiN dielectric is 25 nm.

Then, diamond is bonded to the first n-type doped GaN layer 3 using a bonding material, forming a bonding layer 4 and a diamond layer 5. Specifically, the diamond is placed into a reactive ion etcher and activated by oxygen plasma, the cavity pressure is 100mTor, the power is 300W, the oxygen flow is 50sccm, then the first n-type doped GaN layer 3 and the front surface of the diamond are bonded relatively at room temperature, and bonding annealing is carried out for twenty hours at 200 ℃ to form the bonding layer 4 and the diamond layer 5.

S4, etching the bonding layer 4 and the diamond layer 5 until the first n-type doped GaN layer 3, forming a plurality of nanopores 60, and growing the nanopillar LED structures 6 in the plurality of nanopores 60.

Etching the diamond layer 5 by adopting a photoetching process until the nano holes 60 of the first n-type doped GaN layer are formed, and then growing an n-GaN layer 61 and In sequence from bottom to top by adopting an MOCVD process In the etched places, namely the nano holes, of the diamond layer 5_0.2Ga_0.8An N/GaN MQWs layer 62, an AlGaN layer 63, and a p-GaN layer 64, forming a nanorod LED structure 6.

S5, etching the diamond layer 5 and the bonding layer 4 around the nano-pillar LED structure 6 until the first n-type doped GaN layer 3, forming a plurality of grooves 71, preparing first electrodes 7 in the grooves 71, and preparing second electrodes 8 on the nano-pillar LED structure 6.

And etching the diamond layer 5 and the bonding layer 4 around the nano-pillar by adopting a photoetching process until the first n-type doped GaN layer 3 is formed, forming a plurality of grooves 71, then respectively depositing n-type electrodes on the first n-type doped GaN layer 3 in the grooves 71 by using a metal sputtering method, and depositing p-type electrodes on the p-type doped GaN layer 64 at the top layer, thereby completing the manufacturing of the blue LED device.

EXAMPLE five

Referring to fig. 2 and fig. 3a to fig. 3h, a method for fabricating a 280nm uv nanorod LED structure nested in a diamond layer is described in this embodiment. The preparation method comprises the following steps:

and S1, growing a nucleation layer 2 on the substrate layer 1.

Selecting C-surface Al₂O₃As a backing layer. First, the substrate layer 1 is heat-treated: mixing the c surface Al₂O₃Placing the substrate in MOCVD reaction chamber, and reducing the vacuum degree of the reaction chamber to less than 2 × 10^-2Torr; and introducing hydrogen into the reaction chamber, heating the substrate to 1200 ℃ under the condition that the pressure of the MOCVD reaction chamber reaches 760Torr, and keeping the temperature for 10min to finish the heat treatment of the substrate.

Then, c-plane Al after heat treatment₂O₃And simultaneously introducing ammonia gas with the flow rate of 4000sccm and an aluminum source with the flow rate of 40sccm into the substrate by adopting an MOCVD (metal organic chemical vapor deposition) process at the temperature of 1100 ℃, and growing the high-temperature AlN nucleation layer 2 with the thickness of 70nm under the condition of keeping the pressure of 760 Torr.

S2, growing a first n-type doped GaN layer 3 on the nucleation layer 2.

And (3) adopting an MOCVD process on the AlN nucleating layer, keeping the temperature of an MOCVD reaction chamber at 1100 ℃, simultaneously introducing ammonia gas with the flow rate of 4000sccm, a gallium source with the flow rate of 40sccm and a silicon source with the flow rate of 20sccm, and growing the first n-type doped GaN layer 3 with the thickness of 2500nm under the condition of keeping the pressure of 760 Torr.

S3, bonding alloy diamond on the first n-type doped GaN layer 3, forming the bonding layer 4 and the diamond layer 5.

First, bonding materials are prepared on the diamond surface and the first n-type doped GaN layer 3, respectively. Specifically, a layer of SiN dielectric is deposited as a bonding material on the front surfaces of the diamond and the first n-type doped GaN layer 3 by a chemical vapor deposition method, and the thickness of the SiN dielectric is 40 nm.

Then, diamond is bonded to the first n-type doped GaN layer 3 using a bonding material, forming a bonding layer 4 and a diamond layer 5. Specifically, the diamond is placed into a reactive ion etching machine and activated by oxygen plasma, the cavity pressure is 150mTor, the power is 300W, the oxygen flow is 100sccm, then the first n-type doped GaN layer 3 and the front surface of the diamond are bonded relatively at room temperature, and bonding annealing is carried out for thirty hours at 200 ℃ to form the bonding layer 4 and the diamond layer 5.

S4, etching the bonding layer 4 and the diamond layer 5 until the first n-type doped GaN layer 3, forming a plurality of nanopores 60, and growing the nanopillar LED structures 6 in the plurality of nanopores 60.

Etching the diamond layer 5 by adopting a photoetching process until the nano holes 60 of the first n-type doped GaN layer are formed, and then growing an n-GaN layer 61 and Al in sequence from bottom to top in the etched places, namely the nano holes, of the diamond layer 5 by adopting an MOCVD process_0.43Ga_0.57N/Al_0.6Ga_0.3An N MQWs layer 62, an AlGaN layer 63 and a p-GaN layer 64 forming the nanorod LED structure 6.

S5, etching the diamond layer 5 and the bonding layer 4 around the nano-pillar LED structure 6 until the first n-type doped GaN layer 3, forming a plurality of grooves 71, preparing first electrodes 7 in the grooves 71, and preparing second electrodes 8 on the nano-pillar LED structure 6.

And etching the diamond layer 5 and the bonding layer 4 around the nano-pillar by adopting a photoetching process until the first n-type doped GaN layer 3 is reached to form a plurality of grooves 71, then respectively depositing n-type electrodes on the first n-type doped GaN layer 3 in the grooves 71 by using a metal sputtering method, and depositing p-type electrodes on the p-type doped GaN layer 64 at the top layer to finish the manufacture of the 280nm ultraviolet LED device.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.