A nitride template based on a metal substrate and a preparation method and application thereof

Abstract

The application provides a metal substrate based nitride template, relates to the technical field of semiconductors and communication, and comprises a metal substrate, a two-dimensional material film, an inert material pattern mask layer and a nitride epitaxial layer; the surface of the two-dimensional material film is subjected to activation treatment for providing nucleation sites for growth of the nitride material and inhibiting interface reaction in a high-temperature epitaxial process; the inert material pattern mask layer realizes selective epitaxy of the nitride material, thereby realizing lateral over-epitaxial growth, reducing dislocation density in the nitride epitaxial layer and improving crystal quality of the epitaxial layer. The application also provides a preparation method and application of the template; the composite metal substrate structure of the metal substrate / two-dimensional material film / inert material pattern mask layer can realize direct high-temperature epitaxial growth of high-quality and stress-free nitride material, the template has high scalability, and is suitable for epitaxy and devices of deep ultraviolet LEDs and second-generation semiconductor materials such as GaAs and InP.

Description

TECHNICAL FIELD

[0001] The present application relates to the fields of semiconductor technology and communication, and in particular to a nitride template based on a metal substrate and a preparation method and application thereof. BACKGROUND

[0002] Currently, the substrate for heteroepitaxy of nitride material has low selectivity, mainly being sapphire material. Due to the inherent lattice mismatch and the difference in thermal expansion coefficient between the sapphire substrate and the nitride material, a large number of dislocation density and high residual stress inevitably occur in the nitride epitaxial layer. In addition, the sapphire substrate is brittle and fragile, and has high rigidity, which is completely unsuitable for flexible application of nitride-based devices; more importantly, the sapphire has poor thermal conductivity (thermal conductivity 25 W / mK), which leads to heat accumulation of high-power nitride-based devices and cannot be effectively released, affecting the service life and stability of the device. Generally, in order to meet the heat dissipation requirements of high-power nitride-based devices, laser lift-off or mechanical grinding processes are required to remove or thin the sapphire substrate, and then the device epitaxial layer structure is transferred and combined with high thermal conductivity materials (such as metals and thermally conductive ceramics) to reduce the heat accumulation effect. However, this will inevitably make the device preparation process more complex and increase the manufacturing cost; at the same time, mechanical damage during substrate peeling will also lead to performance degradation and lower yield of the device.

[0003] Metal materials have excellent ductility, and as an epitaxial substrate for nitride materials, it is expected to expand the application potential of devices in the flexible aspect. In addition, compared with the sapphire substrate, the thermal conductivity of the metal (Mo: 138 W / mK) is significantly improved, which helps to solve the heating problem of the device under large current injection. Therefore, how to realize the epitaxy of high-quality nitride materials and high-performance device structures on a metal substrate has great significance and value. However, due to the chemical activity of metal materials, the high-temperature epitaxial growth process of nitride based on MBE and MOCVD will cause strong chemical reaction between the metal substrate and the epitaxial layer, resulting in doping resolution and phase separation of the nitride material. Therefore, the existing epitaxy of nitride materials on metal substrates usually adopts low-temperature deposition processes such as pulsed laser deposition (PLD) to avoid the above chemical reaction; however, due to the low temperature of calcium deposition, it cannot provide sufficient reaction energy for the growth of high-quality nitride materials, and the crystalline quality of the epitaxial material is low. Recently, related research proposes to use graphene as a buffer insertion layer to realize the epitaxy of nitride materials on a metal substrate, which can inhibit the interface reaction to some extent, but the material crystal quality needs to be further improved.

[0004] Therefore, it is necessary to precisely design the epitaxial substrate structure to effectively inhibit the stress and defect formation in the nitride epitaxial process, and realize the preparation of high-quality, stress-free nitride materials and high-performance devices. SUMMARY

[0005] In view of this, the present invention proposes a nitride template based on a metal substrate, its preparation method and application, which solves or at least partially solves the technical defects existing in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A nitride template based on a metal substrate, comprising:

[0008] Metal substrate;

[0009] A two-dimensional material thin film is located on one side of the metal substrate;

[0010] An inert material patterned mask layer is located on the side of the two-dimensional material thin film away from the metal substrate;

[0011] A nitride epitaxial layer is located on the side of the inert material pattern mask layer away from the metal substrate;

[0012] The surface of the two-dimensional material film is activated to provide nucleation sites for the growth of nitride materials. The two-dimensional material film is also used to suppress interfacial reactions during the high-temperature epitaxial process. The inert material pattern mask layer enables selective epitaxy of the nitride material, thereby achieving lateral over-epitaxial growth, reducing the dislocation density in the nitride epitaxial layer, and improving the crystal quality of the epitaxial layer.

[0013] Furthermore, the metal substrate is made of any one of Mo, W, V, Cr, and Ta.

[0014] Furthermore, the material of the two-dimensional thin film is any one of graphene, h-BN, WS2, WSe2, MoS2, and MoSe2.

[0015] Furthermore, the inert material pattern mask layer is made of SiO2 or Si3N4.

[0016] The present invention also provides a method for preparing a nitride template based on a metal substrate as described above, comprising the following steps:

[0017] Preparation of S1 metal substrate / two-dimensional material thin film bilayer structure: The two-dimensional material thin film is directly epitaxially grown on the metal substrate by CVD method, or the two-dimensional material thin film is grown on catalytic metal Ni or Cu foil by CVD method, and then the two-dimensional material thin film is transferred to the metal substrate by wet transfer process;

[0018] Preparation of S2 Inert Material Pattern Mask Layer: An inert film of a certain thickness is deposited on the surface of the two-dimensional material film, and then a mask pattern is prepared on the inert film;

[0019] S3 activating the two-dimensional material film: first, plasma treatment, and then high-temperature nitridation treatment of the two-dimensional material film based on MBE or MOCVD method to form effective doping of N atoms, forming a metal composite substrate;

[0020] S4 preparation of nitride epitaxial layer: first, plasma treatment, and then epitaxial growth of nitride material on the metal composite substrate based on MBE and MOCVD method.

[0021] Further, in step S1, when the material of the two-dimensional material film is graphene, CH4 or C2H4 is used as a precursor material;

[0022] When the material of the two-dimensional material film is h-BN, NH3-BH3 is used as a precursor material;

[0023] When the material of the two-dimensional material film is any one of WS2, WSe2, MoS2, MoSe2, a direct chemical reaction of metal substrate Mo or W with elemental S or Se is used, and the growth temperature is set to 800-1200℃.

[0024] Further, in step S2, the method for preparing a mask pattern on the inert film is any one of photolithography, nano-imprinting and focused ion beam etching;

[0025] The size, shape and period of the mask pattern can be designed, and the thickness of the inert film can be designed.

[0026] Further, in step S2, a photoresist mask pattern is prepared on the inert film using a photolithography process, then the inert film in the area not covered by the photoresist is removed by reactive ion etching with the etching thickness controlled to be less than the thickness of the inert film, then the remaining inert film in the area covered by the photoresist is removed by HF solution chemical etching, and a two-step removal process can avoid damage to the two-dimensional material film caused by direct reactive ion etching, and finally the photoresist mask is removed by an organic solvent;

[0027] In the above method, the etching thickness of the inert film in the area not covered by the photoresist is greater than the remaining thickness.

[0028] The application also provides a nitride template based on a metal substrate for AlGaN-based deep ultraviolet LED device applications, which uses the above-mentioned nitride template based on a metal substrate as a substrate, and sequentially epitaxially grows an n-AlGaN electron transport layer, an AlGaN multi-quantum well structure with alternating high and low Al components, and a p-AlGaN hole transport layer.

[0029] The application also provides application of the metal substrate based nitride template in epitaxy and devices of GaAs or InP second generation semiconductor materials, which uses the metal substrate based nitride template as a substrate to grow epitaxy materials or devices.

[0030] The device is any one of LEDs, photodetectors and HEMTs.

[0031] The metal substrate based nitride template and the preparation method thereof adopt a composite metal substrate structure of a metal substrate / two-dimensional material film / inert material pattern mask layer, the metal substrate helps to solve the heating problem of the device under large current injection and improve the heat dissipation capacity; the two-dimensional material film can effectively inhibit the interface reaction in the high-temperature epitaxy process; the inert material pattern mask layer is used to realize the lateral over-epitaxy growth of the nitride material and improve the crystal quality of the epitaxy layer. The two-dimensional material film is subjected to activation treatment to increase the difference between the two-dimensional material film and the nucleation energy barrier of the nitride on the inert material pattern mask layer, improve the selectivity of the nucleation growth site of the nitride, and realize the direct high-temperature epitaxy growth of high-quality and stress-free nitride material. The application has high scalability, is suitable for deep ultraviolet LED device applications, is also suitable for epitaxy and device applications of GaAs, InP and other second generation semiconductor materials, including but not limited to LEDs, photodetectors and HEMTs, and is suitable for inch-level production technology based on existing semiconductor device process technology. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0033] Figure 1 It is a structural schematic diagram of the metal substrate based nitride template of the application;

[0034] Figure 2 It is a process flow schematic diagram of the preparation method of the metal substrate based nitride template of the application;

[0035] Figure 3 It is a structural schematic diagram of the AlGaN based deep ultraviolet LED device in embodiment 2 of the application;

[0036] The reference signs are explained as follows: 1-metal substrate; 2-two-dimensional material film; 3-inert material pattern mask layer; 4-nitride epitaxy layer. DETAILED DESCRIPTION

[0037] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present application.

[0038] This invention provides a nitride template based on a metal substrate, such as... Figure 1 As shown, it includes:

[0039] Metal substrate 1;

[0040] A two-dimensional material thin film 2 is located on one side of the metal substrate;

[0041] An inert material pattern mask layer 3 is located on the side of the two-dimensional material thin film away from the metal substrate;

[0042] Nitride epitaxial layer 4 is located on the side of the inert material pattern mask layer away from the metal substrate;

[0043] The surface of the two-dimensional material thin film 2 is activated to provide nucleation sites for the growth of nitride materials. The two-dimensional material thin film 2 is also used to suppress interfacial reactions during the high-temperature epitaxial process. The inert material pattern mask layer 3 enables selective epitaxy of nitride materials, thereby achieving lateral over-epitaxial growth, reducing the dislocation density in the nitride epitaxial layer 4, and improving the crystal quality of the epitaxial layer.

[0044] The metal substrate 1 is made of a high-melting-point metal material, including but not limited to Mo, W, V, Cr and Ta, and serves as the initial support substrate.

[0045] The two-dimensional material film 2 is made of low-dimensional materials with strong chemical / thermal stability, such as graphene, h-BN, and transition metal dichalcogenides (TMDs), and serves as a buffer intercalation layer. Because the two-dimensional material surface has no dangling bonds and has a stable structure, interfacial reactions during the high-temperature growth of nitrides can be avoided.

[0046] Based on the catalytic activity of the metal materials themselves, two-dimensional material thin films 2 were directly epitaxially grown on a metal substrate 1 using chemical vapor deposition (CVD). For graphene, CH4 or C2H4 was used as the precursor material; for h-BN, ammonia borane (NH3-BH3) was used as the precursor material; and TMDs could be obtained by direct chemical reaction between the metal substrate and elemental S or Se to obtain WS2 / WSe2 and MoS2 / MoSe2. The growth temperature of the two-dimensional materials was set at 800-1200℃.

[0047] In addition, for the two-dimensional material film 2 grown by CVD on the traditional catalytic metal Ni and Cu foil, the two-dimensional material can also be transferred to a metal support substrate 1 such as Mo and W by a wet transfer process, so as to realize the construction of a metal substrate / two-dimensional material film double-layer structure.

[0048] The material of the inert material pattern mask layer 3 includes but is not limited to SiO2 and Si3N4, etc., so as to realize the selective epitaxy of the nitride material on the surface of the two-dimensional material film 2, and reduce the dislocation density in the epitaxial nitride material by combining with the lateral over-epitaxy technology.

[0049] The application also provides a preparation method of the nitride template based on the metal substrate, and a process flow diagram is shown in Figure 2 The preparation method comprises the following steps:

[0050] S1, preparation of a metal substrate / two-dimensional material film double-layer structure: the two-dimensional material film 2 is directly epitaxially grown on the metal substrate 1 by CVD, or the two-dimensional material film 2 is grown on a catalytic metal Ni or Cu foil by CVD, and then the two-dimensional material film is transferred to the metal substrate 1 by a wet transfer process;

[0051] S2, preparation of an inert material pattern mask layer 3: a certain thickness of inert film is deposited on the surface of the two-dimensional material film 2, and a mask pattern is prepared on the inert film;

[0052] S3, activation treatment of the two-dimensional material film: the two-dimensional material film 2 is subjected to high-temperature nitridation treatment based on MBE or MOCVD to form effective doping of N atoms, so as to form a metal composite substrate;

[0053] S4, preparation of a nitride epitaxial layer 4: the nitride material is epitaxially grown on the metal composite substrate based on MBE and MOCVD.

[0054] In step S2, the method for preparing the mask pattern on the inert film is flexible and diverse, which can be any one of photolithography, nano-imprinting and focused ion beam etching; the size, shape and period of the mask pattern are flexibly adjustable, and the thickness of the inert film can also be appropriately adjusted according to actual requirements.

[0055] For example, a photoresist mask pattern is prepared on the inert film by using a photolithography process, then the inert film in the area without photoresist coverage is removed by using a reactive ion etching method, and the etching thickness is controlled to be less than the thickness of the inert film, then the remaining inert film in the area with photoresist coverage is removed by using HF solution chemical etching, the two-step removal process can avoid the damage to the two-dimensional material film caused by direct reactive ion etching, and finally the photoresist mask is removed by using an organic solvent; wherein the etching thickness of the inert film in the area without photoresist coverage is greater than the remaining thickness.

[0056] In step S3, the unprocessed two-dimensional material film has a complete molecular structure and no dangling bond structure out of plane, so it is difficult to provide nucleation sites for the epitaxy of nitride material. Therefore, the chemical bonds on the surface of the two-dimensional material are first damaged to a certain extent by plasma treatment to form a dangling bond structure, and then effective doping of N atoms is formed by high-temperature nitridation treatment based on MBE or MOCVD to improve the reactivity, thereby providing nucleation sites for the subsequent growth of nitride material.

[0057] In step S4, the nitride material is epitaxially grown on the metal composite substrate based on MBE and MOCVD. Due to the high reactivity of the activated two-dimensional material film 2, compared with inert films such as SiO2 or Si3N4, the nitride material preferentially nucleates and grows on the two-dimensional material film 2, thereby realizing selective epitaxy of the nitride material. In addition, by adjusting the growth process parameters (such as growth temperature, V / Ⅴ, ammonia pulse method, etc.) during the epitaxy of the nitride material, the lateral growth rate of the nitride material is improved, and the effective merging of the epitaxial layer film is promoted, that is, the lateral over-epitaxy process is realized. During the lateral epitaxial merging process of the nitride material, the dislocation lines bend and annihilate towards the merging direction, thereby effectively reducing the dislocation density in the nitride epitaxial layer.

[0058] The application also provides an AlGaN-based deep ultraviolet LED device using the metal substrate-based nitride template. The n-AlGaN electron transport layer, the AlGaN multi-quantum well structure with alternating high and low Al components, and the p-AlGaN hole transport layer are epitaxially grown in sequence on the metal substrate-based nitride template. The thickness, material composition, and doping of each functional layer of the deep ultraviolet LED device are appropriately designed based on the advantages of the metal substrate-based nitride template in heat dissipation. The preparation of the deep ultraviolet LED device can use traditional semiconductor device technology, mainly including device mesa etching and metal electrode deposition. The application has high scalability and is also applicable to the epitaxy and device application of second-generation semiconductor materials such as GaAs and InP, including but not limited to LEDs, photodetectors, and HEMTs.

[0059] Example 1

[0060] The preparation process of the metal substrate-based AlN template is as follows:

[0061] Step S1: A 2 inch double-side polished metal Mo substrate 1 with a thickness of 230 μm and a surface root mean square roughness of less than 2 nm is used. The metal Mo substrate 1 is placed in a high-temperature zone of a double-zone CVD device, and the temperature is set to 950 °C. S powder is placed in a low-temperature zone, and the temperature is set to 140 °C. Ar is used as a carrier gas, and H2 provides a reducing atmosphere. Elemental S reacts directly with the metal Mo substrate 1 to form a two-dimensional MoS2 film 2 on the surface layer. The S vaporization reaction time in the high-temperature zone is set to about 30-60 min.

[0062] Step S2: A 20-50 nm thick SiO2 film is deposited on the Mo metal substrate / two-dimensional MoS2 film by PECVD. Based on the positive photoresist process of AZ5214E photoresist, a corresponding photoresist mask pattern is prepared on the SiO2 film. The preferred pattern is a circular hole with a diameter of 500 nm and a period of 1 μm. Further, a reactive ion etching is used to remove a sufficient thickness (10-40 nm) of the SiO2 film, leaving a remaining thickness of about 10 nm. A 10% volume fraction of HF solution is used to remove the remaining 10 nm of SiO2 film, which can effectively avoid damage to the two-dimensional MoS2 film 2 caused by over-etching of the reactive ion etching. Finally, the photoresist mask pattern is removed in a hot acetone solvent at 80 °C to obtain an inert SiO2 pattern mask layer 3 on the Mo metal substrate / two-dimensional MoS2 film.

[0063] Step S3: The two-dimensional MoS2 film not covered by the inert SiO2 pattern mask layer 3 is etched based on a plasma cleaning machine with air (mainly composed of O2 and N2) flowing in. The processing conditions are as follows: air flow rate of 50 sccm, power of 30%, and processing time of 30 s. The best subsequent doping effect can be obtained while ensuring the integrity of the main molecular structure of the two-dimensional MoS2 film 2.

[0064] Step S4: The metal composite substrate structure is placed in a MOCVD, 5000 sccm of NH3 is introduced, and an activation treatment is performed at 950 °C for 10 min to form a uniform N atom doping, which provides nucleation sites for subsequent epitaxy of AlN material. At a high temperature of 1200-1250 °C, 70 sccm of TMAl and 500-1000 sccm of NH3 are introduced as Al source and N source, respectively, to epitaxially grow an AlN epitaxial layer 4 with a thickness of about 5 μm. Due to the inertness of the inert SiO2 pattern mask layer 3, nucleation and growth of AlN cannot be achieved, and the entire epitaxial process will exhibit a lateral over-epitaxy growth mode.

[0065] Example 2

[0066] An AlGaN-based deep ultraviolet LED device, as shown in FIG. 1, is prepared as follows: Figure 3

[0067] ​Based on the AlN template of metal substrate prepared in Example 1, the device functional layers of deep ultraviolet LEDs, such as n-AlGaN electron transport layer, high-low Al component alternating AlGaN multi-quantum well structure, p-AlGaN hole transport layer, etc., are successively epitaxially grown. Among them, the thickness of the n-AlGaN layer is 400-500 nm, the Si doping concentration is 5×10 8 / cm 3 ; the quantum well layer is a high-low Al component alternating AlGaN multi-quantum well layer, the well thickness is 2 nm, and the Al component mass fraction is 50%; the barrier thickness is 10 nm, and the Al component mass fraction is 60%; the thickness of the p-AlGaN layer is 50-100 nm, and the Mg doping concentration is 1×10 8 / cm 3 . Then, based on the photolithography + "lift-off" process, Ni / Au and Ti / Al are prepared on the mesa to serve as the N electrode and the P electrode of the device, respectively.

[0068] However, based on the traditional semiconductor device process, the mesa structure of the deep ultraviolet LED is prepared, and the specific process is as follows: 500 nm SiO2 is deposited on the deep ultraviolet LED epitaxial wafer as a mask layer based on PECVD, the mask of the device mesa is prepared on the SiO2 mask layer through the photolithography process + reactive ion etching, and the mesa structure is etched on the deep ultraviolet LED based on inductively coupled plasma etching. The size of the mesa prepared here is selected to be a square of 100x100 2 . The traditional process exposes the n-AlGaN electron transport layer of the deep ultraviolet LED.

[0069] The nitride template based on the metal substrate and the preparation method thereof of the application adopt a composite metal substrate structure of metal substrate / two-dimensional material film / inert material pattern mask layer, the metal substrate helps to solve the heating problem of the device under large current injection and improve the heat dissipation capacity; the two-dimensional material film can effectively inhibit the interface reaction in the high-temperature epitaxial process; and the inert material pattern mask layer is used to realize the lateral overgrowth of the nitride material and improve the crystal quality of the epitaxial layer. Among them, the two-dimensional material film is subjected to activation treatment to increase the difference between the two-dimensional material film and the nucleation energy barrier of the nitride on the inert material pattern mask layer, improve the selectivity of the nucleation growth site of the nitride, and realize the direct high-temperature epitaxial growth of high-quality and stress-free nitride material. The application has high scalability and is suitable for application in deep ultraviolet LED devices, and is also suitable for epitaxy and device application of second-generation semiconductor materials such as GaAs and InP, including but not limited to LEDs, photodetectors and HEMTs, etc.; the application is based on existing semiconductor device process technology and is suitable for inch-level production technology.

[0070] The above merely describes some embodiments of the present application, and it should be pointed out that, for those skilled in the art, some improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A nitride template based on a metal substrate, characterized in that, include: Metal substrate; A two-dimensional material thin film is located on one side of the metal substrate; An inert material patterned mask layer is located on the side of the two-dimensional material thin film away from the metal substrate; A nitride epitaxial layer is located on the side of the inert material pattern mask layer away from the metal substrate; The surface of the two-dimensional material thin film is activated to provide nucleation sites for the growth of nitride materials. The two-dimensional material thin film is also used to suppress interfacial reactions during the high-temperature epitaxial process. The inert material pattern mask layer enables selective epitaxy of the nitride material, thereby achieving lateral over-epitaxial growth, reducing the dislocation density in the nitride epitaxial layer, and improving the crystal quality of the epitaxial layer. The material of the two-dimensional material film is any one of WS2, WSe2, MoS2, and MoSe2. The activation treatment of the two-dimensional material film includes: firstly, plasma treatment, and then high-temperature nitriding treatment of the two-dimensional material film with NH3 based on MBE or MOCVD to form effective doping of N atoms and form a metal composite substrate. The gas used for plasma treatment is air.

2. The nitride template based on a metal substrate according to claim 1, characterized in that, The inert material pattern mask layer is made of SiO2 or Si3N4.

3. A method for preparing a nitride template based on a metal substrate as described in any one of claims 1-2, characterized in that, Includes the following steps: Preparation of S1 metal substrate / two-dimensional material thin film bilayer structure: The two-dimensional material thin film is directly epitaxially grown on the metal substrate by CVD method, or the two-dimensional material thin film is grown on catalytic metal Ni or Cu foil by CVD method, and then the two-dimensional material thin film is transferred to the metal substrate by wet transfer process; Preparation of S2 Inert Material Pattern Mask Layer: An inert film of a certain thickness is deposited on the surface of the two-dimensional material film, and then a mask pattern is prepared on the inert film; S3 Activation treatment of the two-dimensional material thin film: First, plasma treatment is used, and then the two-dimensional material thin film is subjected to high-temperature nitriding treatment based on MBE or MOCVD to form effective doping of N atoms and form a metal composite substrate. Preparation of S4 nitride epitaxial layer: Nitride material was epitaxially grown on the metal composite substrate using MBE and MOCVD methods.

4. The method for preparing a nitride template based on a metal substrate according to claim 3, characterized in that, In step S1, when the material of the two-dimensional material film is any one of WS2, WSe2, MoS2, and MoSe2, it is obtained by direct chemical reaction of a metal substrate Mo or W with elemental S or Se, and the growth temperature is set to 800-1200℃.

5. The method for preparing a nitride template based on a metal substrate according to claim 3, characterized in that, In step S2, the method for preparing the mask pattern on the inert thin film is any one of photolithography, nanoimprinting, and focused ion beam etching; The size, shape, and period of the mask pattern can be designed, as can the thickness of the inert film.

6. The method for preparing a nitride template based on a metal substrate according to claim 5, characterized in that, In step S2, a photoresist mask pattern is prepared on an inert thin film using photolithography. Then, reactive ion etching is used to remove the inert thin film in the area without photoresist coverage, while controlling the etching thickness to be less than the thickness of the inert thin film. After that, chemical etching with HF solution is used to remove the remaining inert thin film in the photoresist coverage area. The two-step removal process can avoid damage to the two-dimensional material thin film caused by direct reactive ion etching. Finally, the photoresist mask is removed using an organic solvent. In this case, the etching thickness of the inert film in the area without photoresist coverage is greater than its remaining thickness.

7. An application of a nitride template based on a metal substrate in AlGaN-based deep ultraviolet LED devices, characterized in that, Using the nitride template based on a metal substrate as described in any one of claims 1-2 or the nitride template based on a metal substrate prepared by the method described in any one of claims 3-6 as the substrate, an n-AlGaN electron transport layer, an AlGaN multiple quantum well structure with alternating high and low Al compositions, and a p-AlGaN hole transport layer are sequentially epitaxially grown.

8. An application of a nitride template based on a metal substrate in the epitaxy and devices of GaAs or InP second-generation semiconductor materials, characterized in that, Using the nitride template based on a metal substrate as described in any one of claims 1-2 or the nitride template based on a metal substrate prepared by the method described in any one of claims 3-6 as a substrate, epitaxial materials or devices are grown; The device can be any one of LEDs, photodetectors, and HEMTs.

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