Gallium oxide epitaxial device compatible with multiple process routes and gallium oxide thin film preparation process

Abstract

The invention discloses a gallium oxide epitaxial device compatible with multiple process routes and a gallium oxide thin film preparation process. The gallium oxide epitaxial device comprises a source region, an epitaxial growth region, a transmission system, a tail exhaust system and a cooling system, the source region adopts a furnace tube structure, a gallium boat for containing Ga metal is arranged in the furnace tube, the source region is used for heating the Ga metal and providing Ga-containing gas, and the epitaxial growth region is used for plating a gallium oxide thin film on the surface of a substrate; the gas inlet end of the epitaxial growth area is connected with the source area through a pipeline with a gas flow shut-off valve, a plurality of gas conveying pipes are arranged at the gas inlet end, the gas exhaust end of the epitaxial growth area is connected with the conveying system and the tail exhaust system, the conveying system is used for conveying substrates, and the tail exhaust system is used for exhausting waste gas; and the cooling system is connected with the source region, the epitaxial growth region and the tail exhaust system respectively. The device has the characteristics of compact structure, convenience in operation, high reliability and the like, can be compatible with various process routes to prepare the gallium oxide epitaxial layer, and realizes preparation of the gallium oxide epitaxial layers with different growth rates and different epitaxial thicknesses.

Description

Technical Field

[0001] The present invention relates to the technical field of gallium oxide thin film preparation, and in particular to a gallium oxide epitaxial device and a gallium oxide thin film preparation process compatible with multiple process routes. Background Art

[0002] Gallium oxide (Ga2O3) material has excellent properties such as large bandgap, high breakdown field strength, low on-resistance, and low growth cost. It can be used to make semiconductor devices such as solar-blind ultraviolet optoelectronic devices and high-power power electronic devices. It has strategic significance in the fields of new energy vehicles and next-generation communications. There are five crystal structures of gallium oxide, of which β-Ga2O3 is grown by the melt method. β-Ga2O3 is also the fourth-generation semiconductor material that has been most studied in academia and is closest to application.

[0003] As a strategic advanced semiconductor material, gallium oxide materials have received great attention in recent years. The domestic gallium oxide single crystal substrate preparation technology has developed rapidly, and the development of 6-inch substrates and small-scale commercialization of 4-inch substrates have been achieved. However, the gallium oxide epitaxial growth process is still in the scientific research stage. For gallium oxide power devices, epitaxy is an indispensable link, and the quality of epitaxial film plays a vital role in device performance. The choice of epitaxial equipment and process route determines the quality of epitaxial film and future industrialization costs, so it is necessary to conduct in-depth research on epitaxial equipment and process routes.

[0004] Table 1. Characteristics of various processes in the prior art

[0005]

[0006]

[0007] At present, the technical routes used to prepare gallium oxide epitaxial materials in the existing technology include MBE, HVPE, OVPE, LPCVD, MOCVD, Mist-CVD, etc. As can be seen from Table 1, the various current gallium oxide epitaxial film preparation process routes have their own advantages and disadvantages. For example, the MBE method has an extremely low deposition rate and is expensive. It is only suitable for manufacturing lateral devices and is not suitable for future industrialization needs. Therefore, it is mainly used for laboratory research; the Mist-CVD method is extremely difficult to control fogging, and its application field is also relatively limited, making it difficult to promote on a large scale; the existing HVPE and OVPE methods use a quartz furnace tube structure in the growth zone, which is easy to react with the H2O vapor in the source gas to generate Si during the growth of the epitaxial film, resulting in uncontrollable Si element doping; the MOCVD method has the disadvantages of low raw material utilization and uncontrollable C element doping, and TMGa is 5 to 10 times more expensive than metal Ga, and the cost of the epitaxial process is high, which limits the exploration of the MOCVD method by various units. The presence of uncontrollable Cl, Si or C element doping in the above epitaxial methods will lead to uncontrollable doping concentration of epitaxial thin films, which will seriously affect the stability characteristics of high-voltage (>3kV) power devices. Therefore, the various gallium oxide epitaxial equipment and process routes are currently in the early stages of research and development, and there is no unified and more advantageous process route, nor has a gallium oxide epitaxial device that can realize the integration of multiple epitaxial processes been developed. Further exploration of high-quality gallium oxide epitaxy methods is needed to meet the future needs of gallium oxide epitaxy industrialization. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a gallium oxide epitaxial device and a gallium oxide thin film preparation process which are compact in structure, easy to operate, highly stable and compatible with multiple process routes, in view of the current application prospects of gallium oxide devices and the research needs of various current epitaxial process routes.

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0010] A gallium oxide epitaxial device compatible with multiple process routes comprises: a source region, an epitaxial growth region, a conveying system, a tail exhaust system and a cooling system; the source region adopts a furnace tube structure, and a gallium boat for holding Ga metal is arranged in the furnace tube, the source region is used to heat Ga metal and provide Ga-containing gas, and the epitaxial growth region is used to plate a gallium oxide film on the surface of a substrate; the air inlet end of the epitaxial growth region is connected to the source region through a pipeline with an air flow shut-off valve, and the air inlet end of the epitaxial growth region is provided with a plurality of gas delivery pipes, the exhaust end of the epitaxial growth region is respectively connected to the conveying system and the tail exhaust system, the conveying system is used to transport substrates in and out of the epitaxial growth region, and the tail exhaust system is used to exhaust waste gas in the epitaxial growth region; the cooling system is respectively connected to the source region, the epitaxial growth region and the tail exhaust system to realize cooling of the source region, the epitaxial growth region and the tail exhaust system.

[0011] As a further improvement of the present invention, the multiple gas delivery pipes at the air inlet end of the epitaxial growth zone are respectively connected to the doping source, oxygen source, Mo source and N2 / Ar source, and at least one extended gas delivery pipe is reserved at the air inlet end of the epitaxial growth zone; the epitaxial growth zone is provided with a heating assembly to achieve heating of the epitaxial growth zone to a preset epitaxial process temperature.

[0012] As a further improvement of the present invention, the epitaxial growth zone includes an outer wall chamber and an inner wall chamber which are nested, the outer wall chamber adopts a double-layer water-cooling structure, and the double-layer water-cooling structure is connected to the cooling system; a uniform flow component is provided on one side of the inner wall chamber, and the uniform flow component is connected to the source area and the gas delivery pipe to achieve uniform distribution of process gas in the inner wall chamber; a growth chamber is provided in the inner wall chamber, and the substrate is placed in the growth chamber to carry out the epitaxial process.

[0013] As a further improvement of the present invention, the growth chamber includes two graphite heaters which are symmetrical up and down and have a gap between them; a substrate base for placing a substrate is provided on the graphite heater on the lower side, and the substrate base is connected to a rotating mechanism, and the rotating mechanism drives the substrate base and the substrate to rotate synchronously.

[0014] As a further improvement of the present invention, the substrate base is inclined by 0° to 5° toward the gas source.

[0015] As a further improvement of the present invention, the source region includes an outer tube and an inner tube, and the outer tube and the inner tube are nested to form a furnace tube structure. The gas inlet end of the furnace tube structure is provided with a plurality of gas delivery pipes, which are respectively connected to a Cl2 source, an H2O vapor source, an Ar source or an N2 source, for delivering process gas to the source region; a resistance heating component is provided between the outer tube and the inner tube to achieve heating of the source region to a preset Ga-containing gas preparation temperature.

[0016] As a general technical concept, the present invention also provides a gallium oxide thin film preparation process based on the gallium oxide epitaxial device compatible with multiple process routes, wherein the preparation process is a HVPE process, comprising the following steps:

[0017] The first step is to place metal Ga in the gallium boat and transport the substrate to the epitaxial growth area through the transport system;

[0018] Step 2: Heat the source area and maintain it at 850°C ± 10°C by means of a resistance heating assembly;

[0019] Step 3: Heat the epitaxial growth area and maintain it at 1050°C ± 10°C through a heating assembly on the epitaxial growth area, and maintain the pressure of the epitaxial growth area at 800mbar ± 10mbar through a tail exhaust system;

[0020] Step 4: Using N2 as carrier gas, Cl2 is introduced into the gas inlet of the source region to react with the metal Ga in the gallium boat to generate GaCl gas, which then enters the epitaxial growth region through a pipeline with a gas flow shutoff valve.

[0021] Step 5: O2 and doping gas are introduced into the epitaxial growth area. O2 reacts with GaCl gas to generate Ga2O3, which is then deposited on the surface of the substrate to form a thin film.

[0022] As a general technical concept, the present invention also provides a gallium oxide thin film preparation process based on the gallium oxide epitaxial device compatible with multiple process routes, wherein the preparation process is an OVPE process, comprising the following steps:

[0023] The first step is to place metal Ga in the gallium boat and transport the substrate to the epitaxial growth area through the transport system;

[0024] Step 2: Heat the source area and maintain it at 700°C ± 10°C by means of a resistance heating assembly;

[0025] Step 3: heat the epitaxial growth area through the heating assembly on the epitaxial growth area and maintain it at 900°C±10°C; maintain the pressure of the epitaxial growth area at 800mbar±10mbar through the tail exhaust system;

[0026] Step 4: Using N2 as carrier gas, H2O vapor is introduced into the gas inlet of the source region to react with the metal Ga in the gallium boat to generate Ga2O gas, which then enters the epitaxial growth region through a pipeline with a gas flow shutoff valve.

[0027] Step 5: O2 and doping gas are introduced into the epitaxial growth area. O2 reacts with Ga2O gas to generate Ga2O3, which is then deposited on the surface of the substrate to form a thin film.

[0028] As a general technical concept, the present invention also provides a gallium oxide thin film preparation process based on the gallium oxide epitaxial device compatible with multiple process routes, wherein the preparation process is a LPCVD process, comprising the following steps:

[0029] The first step is to place metal Ga in the gallium boat and transport the substrate to the epitaxial growth area through the transport system;

[0030] The second step is to introduce N2 to purge the source area and epitaxial growth area;

[0031] Step 3: heat the epitaxial growth area through the heating assembly on the epitaxial growth area and maintain it at 950°C±10°C; maintain the pressure of the epitaxial growth area at 5mbar±1mbar through the tail exhaust system;

[0032] Step 4: The source area is heated and maintained at 800°C ± 10°C by a resistance heating assembly, and the metal Ga in the gallium boat forms Ga vapor;

[0033] Step 5: N2 or Ar is introduced as a carrier gas at the gas inlet end of the source region to carry Ga vapor into the epitaxial growth region through a pipeline with a gas flow shut-off valve;

[0034] Step 6: O2 and doping gas are introduced into the epitaxial growth area. O2 reacts with Ga vapor to generate Ga2O3, which is then deposited on the surface of the substrate to form a thin film.

[0035] As a general technical concept, the present invention also provides a gallium oxide thin film preparation process based on the gallium oxide epitaxial device compatible with multiple process routes, wherein the preparation process is a MOCVD process, comprising the following steps:

[0036] The first step is to transport the substrate to the epitaxial growth area through a transport system;

[0037] Step 2: N2 is introduced to purge the source area and the epitaxial growth area. After the purge is completed, the gas flow shut-off valve is closed;

[0038] Step 3: heat the epitaxial growth area through the heating assembly on the epitaxial growth area and maintain it at 900°C±10°C; maintain the pressure of the epitaxial growth area at 600mbar±10mbar through the tail exhaust system;

[0039] Step 4: TMGa precursor, O2 and doping gas are introduced into the epitaxial growth area. O2 reacts with the TMGa precursor to generate Ga2O3, and Ga2O3 is deposited on the surface of the substrate to form a thin film.

[0040] Compared with the prior art, the advantages of the present invention are:

[0041] 1. The gallium oxide epitaxial growth device compatible with multiple process routes of the present invention sets the source area and the epitaxial growth area independently, connects the source area and the epitaxial growth area through a pipeline with a gas flow shut-off valve, and uses the source area to heat Ga metal, thereby realizing stable delivery of Ga-containing gas to the epitaxial growth area. The device has the characteristics of compact structure, good maintainability, convenient installation and low cost. At the same time, multiple gas delivery pipes are also set at the end of the epitaxial growth area, which can deliver corresponding process gases according to actual process requirements, integrate MOCVD, HVPE, OVPE and LPCVD process capabilities, can be well compatible with multiple process routes to prepare gallium oxide epitaxial layers, and provides gallium oxide epitaxial layer preparation schemes with different growth rates and different epitaxial thicknesses, providing a new solution for the preparation of gallium oxide epitaxial layers, greatly reducing the research cost of gallium oxide epitaxy, and meeting the scientific research and exploration needs of preparing gallium oxide epitaxial layers.

[0042] 2. The gallium oxide epitaxial device compatible with multiple process routes of the present invention drives the substrate base and the substrate to rotate synchronously through a rotating mechanism, and is assisted by a substrate micro-angle adjustment function to compensate for the loss of source gas along the way, thereby improving process uniformity.

[0043] 3. The gallium oxide thin film preparation process of the present invention is implemented based on the above-mentioned gallium oxide epitaxial device, which significantly improves the film quality of the epitaxial layer, realizes precise control of the doping concentration, and effectively improves the stability and reliability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 A schematic diagram of the structural principle of a gallium oxide epitaxial device in a specific embodiment of the present invention;

[0045] Figure 2 This is a schematic diagram of the HVPE process flow in a specific embodiment of the present invention;

[0046] Figure 3 This is a schematic diagram of the OVPE process flow in a specific embodiment of the present invention;

[0047] Figure 4 This is a schematic diagram of the LPCVD process flow in a specific embodiment of the present invention;

[0048] Figure 5 It is a schematic diagram of the MOCVD process flow in a specific embodiment of the present invention;

[0049] Legend: 1. Substrate; 100. Source region; 101. Gallium boat; 102. Outer tube; 103. Inner tube; 104. Resistance heating assembly; 105. SCR; 106. Airflow shut-off valve; 107. Temperature controller; 108. Temperature measuring element; 200. Epitaxial growth region; 201. Outer wall chamber; 202. Induction heating coil; 203. Inner wall chamber; 204. Graphite heater; 205. Flow uniformization assembly; 300. Conveying system; 400. Tail exhaust system; 500. Tail gas processor; 600. Cooling system. DETAILED DESCRIPTION

[0050] The present invention is further described below in conjunction with the accompanying drawings and specific preferred embodiments, but the protection scope of the present invention is not limited thereby.

[0051] In the description of the present invention, it should be understood that the terms "side", "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0052] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0053] Example 1

[0054] like Figure 1As shown, the gallium oxide epitaxial device compatible with multiple process routes of the present invention comprises: a source region 100, an epitaxial growth region 200, a conveying system 300, a tail exhaust system 400 and a cooling system 600. The source region 100 adopts a furnace tube structure, and a gallium boat 101 for holding Ga metal is arranged in the furnace tube. The source region 100 is used to heat Ga metal and provide Ga-containing gas, and the epitaxial growth region 200 is used to realize the coating of a gallium oxide film on the surface of a substrate 1. The source region 100 and the epitaxial growth region 200 are arranged side by side, and the air inlet end of the epitaxial growth region 200 is connected to the source region 100 through a pipeline with an air flow shut-off valve 106, and the air inlet end of the epitaxial growth region 200 is provided with a plurality of gas delivery pipes, and the exhaust end of the epitaxial growth region 200 is respectively connected to the transmission system 300 and the tail exhaust system 400, the transmission system 300 is used to transmit the substrate 1 in and out of the epitaxial growth region 200, and the tail exhaust system 400 is used to exhaust the exhaust gas in the epitaxial growth region 200, and transport it to the tail gas processor 500 for treatment before being discharged. The cooling system 600 is respectively connected to the source region 100, the epitaxial growth region 200 and the tail exhaust system 400, to achieve cooling of the source region 100, the epitaxial growth region 200 and the tail exhaust system 400, so as to ensure the cooling of high-heat components and improve the safety and reliability of the equipment. The cooling system 600 is provided with a water flow and water temperature detection component to achieve accurate control of the cooling effect of each high-heat component. It is known that the conveying system 300 can adopt conventional technical means in the art, and its main function is to realize the automatic loading and unloading of gallium oxide substrates from the loading and unloading area to the epitaxial growth area 200. In this embodiment, an electric control system can also be set to realize the automatic control of the whole machine and safe start and stop operations.

[0055] In this embodiment, by setting the source region 100 and the epitaxial growth region 200 independently from each other, and connecting the source region 100 and the epitaxial growth region 200 through a pipeline with a gas flow shut-off valve 106, the source region 100 is used to heat the Ga metal, so that the Ga-containing gas is stably transported to the epitaxial growth region 200, which has the characteristics of compact structure, good maintainability, convenient installation and low cost. At the same time, a plurality of gas delivery pipes are also set at the end of the epitaxial growth region 200, which can transport the corresponding process gas according to the actual process requirements, integrate the process capabilities of MOCVD, HVPE, OVPE and LPCVD, can be well compatible with a variety of process routes to prepare gallium oxide epitaxial layers, and provide gallium oxide epitaxial layer preparation solutions with different growth rates and different epitaxial thicknesses, which provides a new solution for the preparation of gallium oxide epitaxial layers, greatly reduces the research cost of gallium oxide epitaxy, and meets the scientific research and exploration needs of preparing gallium oxide epitaxial layers.

[0056] like Figure 1As shown, multiple gas delivery pipes at the gas inlet end of the epitaxial growth zone 200 are respectively connected to the doping source, oxygen source, Mo source and N2 / Ar source, and at least one extended gas delivery pipe is reserved at the gas inlet end of the epitaxial growth zone 200 to facilitate the expansion of the process. Through the setting of the epitaxial growth zone 200, various epitaxial processes can share the functional systems such as substrate 1 transmission, heating, and pressure control, which improves the process window range of the device, realizes the integration of existing multi-machine functions, and greatly reduces the cost of gallium oxide epitaxy research.

[0057] In this embodiment, the epitaxial growth zone 200 is provided with a heating component to achieve heating of the epitaxial growth zone 200 to a preset epitaxial process temperature. Specifically, a heating component is provided outside the outer wall chamber 201, or a heating component is provided between the outer wall chamber 201 and the inner wall chamber 203, to achieve uniform heating of the epitaxial growth zone 200. When induction heating is adopted, an induction heating coil 202 is concentrically arranged on the surface of the outer wall chamber 201, and the outer wall chamber 201 is made of quartz. When resistance heating is adopted, multiple sections of resistance wire heating are arranged between the outer wall chamber 201 and the inner wall chamber 203, and the outer wall chamber 201 is made of metal.

[0058] In this embodiment, a transparent observation window made of quartz material is provided at the exhaust end of the outer wall chamber 201. Combined with the infrared temperature measuring probe provided in the inner wall chamber 203, the reaction temperature of the substrate base can be measured in real time. The remote host computer reads the temperature value in real time and adjusts the power and frequency of the induction power input or the power of the thyristor input in the resistance heating according to the temperature deviation, so that the epitaxial growth zone 200 is uniformly controllable in a wide temperature range of 550°C to 1400°C, and the temperature uniformity is ≤±0.5°C, thereby realizing precise control of the reaction temperature of the growth chamber and improving the process stability.

[0059] like Figure 1 As shown, the epitaxial growth zone 200 includes an outer wall chamber 201 and an inner wall chamber 203 which are nested. The inner wall chamber 203 is made of a material that does not react with O2, H2O, Cl2, HCl, etc., preferably a high-purity SiC material and a high-purity SiC coating or a TaC coating graphite material, and other materials with heating and heat preservation functions and that do not react with process gases can also be selected. The outer wall chamber 201 must have sufficient strength to support the weight of the materials such as the inner wall chamber 203. The outer wall chamber 201 adopts a double-layer water-cooling structure, and the double-layer water-cooling structure is connected to the cooling system 600 to achieve cooling of the epitaxial growth zone 200. A uniform flow component 205 is provided on one side of the inner wall chamber 203, and the uniform flow component 205 is connected to the source area 100 and the gas delivery pipe to achieve uniform distribution of process gases in the inner wall chamber 203. The uniform flow component 205 can specifically adopt the form of a combination of a uniform flow plate and a spray plate to improve the uniformity of gas distribution.

[0060] In this embodiment, a growth chamber is provided in the inner wall chamber 203, and the substrate 1 is placed in the growth chamber for epitaxial process. Specifically, the growth chamber is placed in the center relative to the inner wall chamber 203, and the growth chamber includes two graphite heaters 204 which are symmetrical up and down and have a gap. The surface of the graphite heater 204 is coated with a high-purity SiC or TaC coating. Both graphite heaters 204 adopt a semicircular structure, and the gap between the two graphite heaters 204 is 4cm to 5cm. A substrate base for placing the substrate 1 is provided on the graphite heater 204 located on the lower side, and the substrate base is connected to a rotating mechanism, and the rotating mechanism drives the substrate base and the substrate 1 to rotate synchronously.

[0061] In this embodiment, the rotating mechanism can adopt conventional technical means in the field, preferably an air flotation design, or a motor + magnetic fluid sealing method, etc. The rotating mechanism drives the substrate base to rotate, which can realize the self-rotation of the substrate 1 to improve the consistency of the temperature flow field on the surface of the substrate 1, thereby improving the uniformity of the epitaxial thickness and concentration.

[0062] In this embodiment, the substrate base is designed with a micro-angle adjustment function. For example, an adjustment screw can be set on one side of the substrate base to achieve an angle tilt of the substrate base toward the gas source, which helps to compensate for the concentration loss caused by epitaxial film deposition when the reaction gas moves from the inlet to the outlet, and further optimizes the process uniformity. Specifically, the substrate base is a monolithic design with an adjustable angle of 0° to 5°.

[0063] like Figure 1 As shown, the source region 100 includes an outer tube 102 and an inner tube 103. The outer tube 102 and the inner tube 103 are nested to form a furnace tube structure, and a plurality of gas delivery pipes are provided at the gas inlet end of the furnace tube structure to be respectively connected to a Cl2 source, a H2O vapor source, an Ar source or a N2 source to deliver process gas to the source region 100 to react with the metal gallium placed in the gallium boat 101 to generate GaCl gas or Ga2O gas, and the GaCl gas or Ga2O gas is delivered to the epitaxial growth region 200 under the carrier gas N2 or Ar.

[0064] A resistance heating assembly 104 is provided between the outer tube 102 and the inner tube 103 to heat the source region 100 to a preset Ga-containing gas preparation temperature. Figure 1 As shown, a temperature measurement and control circuit is formed by a thyristor 105, a temperature control meter 107 and a temperature measuring element 108 to control the resistance heating component 104, so that the heating temperature can be uniformly controlled within a range of 500°C to 1400°C.

[0065] In this embodiment, the outer tube 102 adopts a double-layer water-cooling structure and is connected to the cooling system 600 to achieve cooling of the source area 100 .

[0066] In this embodiment, the source region 100 and the epitaxial growth region 200 use inner walls made of high-purity SiC / TaC material, which effectively avoids the influence of unintentional doping of the epitaxial film by Si or C, metal and non-metal impurities contained in the quartz inner tube of the existing HVPE device or the graphite heating body of the MOCVD device, thereby greatly improving the film quality of the epitaxial layer, achieving precise control of the doping concentration, and effectively improving the stability and reliability of the device.

[0067] In this embodiment, the tail exhaust system 400 includes a dry pump and a connecting pipe with a butterfly valve, the connecting pipe is connected to the cooling system 600, one end of the connecting pipe is connected to the dry pump, and the other end of the connecting pipe is connected to the epitaxial growth area 200 to extract the exhaust gas in the epitaxial growth area 200 and realize exhaust gas cooling. Specifically, the corrosion-resistant dry pump is matched with the butterfly valve, and a thin film gauge is set in the connecting pipe to realize the atmosphere and pressure control of the epitaxial growth area 200, so as to realize the pressure controllable from atmospheric pressure to 5Pa. In order to improve the operating stability of the dry pump, a filter can be set in the connecting pipe, and the exhaust gas discharged from the epitaxial growth area 200 enters the dry pump after filtering.

[0068] Example 2

[0069] like Figure 2 As shown, the gallium oxide thin film preparation process of the present invention is a HVPE process, which is implemented based on the gallium oxide epitaxial device in Example 1 and includes the following steps:

[0070] In the first step, metal Ga is placed in the gallium boat 101 , and the substrate 1 is transported to the epitaxial growth area 200 through the transport system 300 .

[0071] In the second step, the source region 100 is heated and maintained at 850° C. by the resistance heating assembly 104 .

[0072] The third step is to heat the epitaxial growth zone 200 and maintain it at 1050° C. through the induction heating coil 202 on the outer wall chamber 201 , and maintain the pressure of the epitaxial growth zone 200 at 800 mbar through the tail exhaust system 400 .

[0073] In the fourth step, N2 is used as a carrier gas, and Cl2 is introduced into the gas inlet end of the source region 100 to react with the metal Ga in the gallium boat 101 to generate GaCl gas, and the GaCl gas enters the epitaxial growth region 200 through a pipeline with a gas flow shut-off valve 106; it can be understood that the amount of Cl2 introduced can be adjusted according to actual process requirements.

[0074] Step 5: O2 and doping gas are introduced into the epitaxial growth region 200, O2 reacts with GaCl gas to generate Ga2O3, and Ga2O3 is deposited on the surface of the substrate 1 to form a thin film. It can be understood that the amount of O2 and doping gas introduced can be adjusted according to actual process requirements.

[0075] Example 3

[0076] like Figure 3 As shown, the gallium oxide thin film preparation process of the present invention is an OVPE process, which is implemented based on the gallium oxide epitaxial device in Example 1 and includes the following steps:

[0077] In the first step, metal Ga is placed in the gallium boat 101 , and the substrate 1 is transported to the epitaxial growth area 200 through the transport system 300 .

[0078] In the second step, the source region 100 is heated and maintained at 700° C. by the resistance heating assembly 104 .

[0079] The third step is to heat the epitaxial growth zone 200 and maintain it at 900° C. through the induction heating coil 202 on the outer wall chamber 201 ; and maintain the pressure of the epitaxial growth zone 200 at 800 mbar through the tail exhaust system 400 .

[0080] In the fourth step, N2 is used as a carrier gas, and H2O vapor is introduced into the gas inlet end of the source region 100 to react with the metal Ga in the gallium boat 101 to generate Ga2O gas, and the Ga2O gas enters the epitaxial growth region 200 through a pipeline with a gas flow shut-off valve 106. It can be understood that the amount of H2O vapor introduced can be adjusted according to actual process requirements.

[0081] Step 5: O2 and doping gas are introduced into the epitaxial growth region 200, O2 reacts with Ga2O gas to generate Ga2O3, and Ga2O3 is deposited on the surface of the substrate 1 to form a thin film. It can be understood that the amount of O2 and doping gas introduced can be adjusted according to actual process requirements.

[0082] Example 4

[0083] like Figure 4 As shown, the gallium oxide thin film preparation process of the present invention is a LPCVD process, which is implemented based on the gallium oxide epitaxial device in Example 1 and includes the following steps.

[0084] In the first step, metal Ga is placed in the gallium boat 101 , and the substrate 1 is transported to the epitaxial growth area 200 through the transport system 300 .

[0085] In the second step, N2 is introduced to purge the source region 100 and the epitaxial growth region 200.

[0086] The third step is to heat the epitaxial growth zone 200 and maintain it at 950° C. through the induction heating coil 202 on the outer wall chamber 201 ; and maintain the pressure of the epitaxial growth zone 200 at 5 mbar through the tail exhaust system 400 .

[0087] Step 4: The source region 100 is heated and maintained at 800° C. by the resistance heating assembly 104 , and the metal Ga in the gallium boat 101 forms Ga vapor.

[0088] Step 5: N2 or Ar is introduced as a carrier gas at the gas inlet end of the source region 100 to carry Ga vapor into the epitaxial growth region 200 through a pipeline with a gas flow shut-off valve 106.

[0089] Step 6: O2 and doping gas are introduced into the epitaxial growth region 200, O2 reacts with Ga vapor to generate Ga2O3, and Ga2O3 is deposited on the surface of the substrate 1 to form a thin film. It can be understood that the amount of O2 and doping gas introduced can be adjusted according to actual process requirements.

[0090] Example 5

[0091] like Figure 5 As shown, the gallium oxide thin film preparation process of the present invention is a MOCVD process, which is implemented based on the gallium oxide epitaxial device in Example 1 and includes the following steps:

[0092] In the first step, the substrate 1 is transported to the epitaxial growth area 200 by the transport system 300 .

[0093] The second step is to introduce N2 to purge the source region 100 and the epitaxial growth region 200. After the purge is completed, the gas flow shut-off valve 106 is closed to isolate the source region 100 from the epitaxial growth region 200, and the pressure in the cavity of the source region 100 is kept slightly higher than the atmospheric pressure.

[0094] The third step is to heat the epitaxial growth zone 200 and maintain it at 900° C. through the induction heating coil 202 on the outer wall chamber 201 ; and maintain the pressure of the epitaxial growth zone 200 at 600 mbar through the tail exhaust system 400 .

[0095] Step 4: TMGa precursor, O2 and doping gas are introduced into the epitaxial growth region 200, O2 reacts with the TMGa precursor to generate Ga2O3, and Ga2O3 is deposited on the surface of the substrate 1 to form a thin film. It can be understood that the amount of TMGa precursor, O2 and doping gas introduced can be adjusted according to actual process requirements.

[0096] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A gallium oxide epitaxial device compatible with multiple process routes, characterized in that: include: A source region (100), an epitaxial growth region (200), a conveying system (300), a tail exhaust system (400) and a cooling system (600); the source region (100) adopts a furnace tube structure, and a gallium boat (101) for containing Ga metal is arranged in the furnace tube; the source region (100) is used to heat Ga metal and provide Ga-containing gas; the epitaxial growth region (200) is used to plate a gallium oxide film on the surface of a substrate (1); the gas inlet end of the epitaxial growth region (200) is connected to the source region (100) through a pipeline with a gas flow shut-off valve (106), and the epitaxial growth region (200) is connected to the source region (100) through a pipeline with a gas flow shut-off valve (106); The gas inlet end of the epitaxial growth zone (200) is provided with a plurality of gas delivery pipes, the gas exhaust end of the epitaxial growth zone (200) is respectively connected to a delivery system (300) and a tail exhaust system (400), the delivery system (300) is used to transport the substrate (1) in and out of the epitaxial growth zone (200), and the tail exhaust system (400) is used to exhaust the waste gas in the epitaxial growth zone (200); the cooling system (600) is respectively connected to the source zone (100), the epitaxial growth zone (200) and the tail exhaust system (400), so as to realize cooling of the source zone (100), the epitaxial growth zone (200) and the tail exhaust system (400).

2. The gallium oxide epitaxial device compatible with multiple process routes according to claim 1, characterized in that: The multiple gas delivery pipes at the gas inlet end of the epitaxial growth zone (200) are respectively connected to a doping source, an oxygen source, a Mo source and an N2 / Ar source, and at least one extended gas delivery pipe is reserved at the gas inlet end of the epitaxial growth zone (200); the epitaxial growth zone (200) is provided with a heating component to achieve heating of the epitaxial growth zone (200) to a preset epitaxial process temperature.

3. The gallium oxide epitaxial device compatible with multiple process routes according to claim 2, characterized in that: The epitaxial growth region (200) comprises an outer wall chamber (201) and an inner wall chamber (203) which are nested, the outer wall chamber (201) adopts a double-layer water cooling structure, and the double-layer water cooling structure is connected to a cooling system (600); a uniform flow component (205) is provided on one side of the inner wall chamber (203), and the uniform flow component (205) is connected to a source region (100) and a gas delivery pipe to achieve uniform distribution of process gas in the inner wall chamber (203); a growth chamber is provided in the inner wall chamber (203), and the substrate (1) is placed in the growth chamber to perform an epitaxial process.

4. The gallium oxide epitaxial device compatible with multiple process routes according to claim 3, characterized in that: The growth chamber comprises two graphite heaters (204) which are symmetrical in upper and lower parts and have a gap therebetween; a substrate base for placing a substrate (1) is provided on the graphite heater (204) located on the lower side, and the substrate base is connected to a rotating mechanism, and the rotating mechanism drives the substrate base and the substrate (1) to rotate synchronously.

5. The gallium oxide epitaxial device compatible with multiple process routes according to claim 4, characterized in that: The substrate base is inclined toward the gas source by 0° to 5°.

6. The gallium oxide epitaxial device compatible with multiple process routes according to any one of claims 1 to 4, characterized in that: The source region (100) comprises an outer tube (102) and an inner tube (103), wherein the outer tube (102) and the inner tube (103) are nested to form a furnace tube structure, wherein a plurality of gas delivery tubes are provided at the gas inlet end of the furnace tube structure, respectively connected to a Cl2 source, an H2O vapor source, an Ar source or an N2 source, for delivering process gas to the source region (100); a resistance heating component (104) is provided between the outer tube (102) and the inner tube (103), so as to heat the source region (100) to a preset Ga-containing gas preparation temperature.

7. A gallium oxide thin film preparation process based on the gallium oxide epitaxial device compatible with multiple process routes according to any one of claims 1 to 6, characterized in that: The preparation process is a HVPE process, comprising the following steps: The first step is to place metal Ga in a gallium boat (101), and to transport a substrate (1) to an epitaxial growth region (200) through a transport system (300); Step 2: heating the source region (100) by means of a resistance heating assembly (104) and maintaining the temperature at 850°C ±10°C; Step 3: heating the epitaxial growth region (200) by means of a heating assembly on the epitaxial growth region (200) and maintaining the temperature at 1050°C±10°C, and maintaining the pressure of the epitaxial growth region (200) at 800mbar±10mbar by means of a tail exhaust system (400); Step 4: Using N2 as carrier gas, Cl2 is introduced into the gas inlet of the source region (100) to react with the metal Ga in the gallium boat (101) to generate GaCl gas, and the GaCl gas enters the epitaxial growth region (200) through a pipeline with a gas flow shut-off valve (106); Step 5: O2 and doping gas are introduced into the epitaxial growth region (200), and O2 reacts with GaCl gas to generate Ga2O3, which is then deposited on the surface of the substrate (1) to form a thin film.

8. A gallium oxide thin film preparation process based on the gallium oxide epitaxial device compatible with multiple process routes according to any one of claims 1 to 6, characterized in that: The preparation process is an OVPE process, comprising the following steps: The first step is to place metal Ga in a gallium boat (101), and to transport a substrate (1) to an epitaxial growth region (200) through a transport system (300); Step 2: heating the source region (100) by means of a resistance heating assembly (104) and maintaining the temperature at 700°C ±10°C; Step 3: heating the epitaxial growth region (200) by means of a heating component on the epitaxial growth region (200) and maintaining the temperature at 900°C±10°C; maintaining the pressure of the epitaxial growth region (200) at 800mbar±10mbar by means of a tail exhaust system (400); Step 4: Using N2 as carrier gas, H2O vapor is introduced into the gas inlet end of the source region (100) to react with the metal Ga in the gallium boat (101) to generate Ga2O gas, and the Ga2O gas enters the epitaxial growth region (200) through a pipeline with a gas flow shut-off valve (106); Step 5: O2 and doping gas are introduced into the epitaxial growth region (200), and O2 reacts with Ga2O gas to generate Ga2O3, which is then deposited on the surface of the substrate (1) to form a thin film.

9. A gallium oxide thin film preparation process based on the gallium oxide epitaxial device compatible with multiple process routes according to any one of claims 1 to 6, characterized in that: The preparation process is a LPCVD process, comprising the following steps: The first step is to place metal Ga in a gallium boat (101), and to transport a substrate (1) to an epitaxial growth region (200) through a transport system (300); Step 2: introducing N2 to purge the source region (100) and the epitaxial growth region (200); Step 3: heating the epitaxial growth region (200) through a heating component on the epitaxial growth region (200) and maintaining the temperature at 950°C±10°C; maintaining the pressure of the epitaxial growth region (200) at 5mbar±1mbar through a tail exhaust system (400); Step 4: The source region (100) is heated and maintained at 800°C±10°C by a resistance heating component (104), and the metal Ga in the gallium boat (101) is transformed into Ga vapor; Step 5: N2 or Ar is introduced as a carrier gas at the gas inlet end of the source region (100) to carry Ga vapor through a pipeline with a gas flow shutoff valve (106) into the epitaxial growth region (200); Step 6: O2 and doping gas are introduced into the epitaxial growth region (200), and O2 reacts with Ga vapor to generate Ga2O3, which is then deposited on the surface of the substrate (1) to form a thin film.

10. A gallium oxide thin film preparation process based on the gallium oxide epitaxial device compatible with multiple process routes according to any one of claims 1 to 6, characterized in that: The preparation process is a MOCVD process, comprising the following steps: The first step is to transport the substrate (1) to the epitaxial growth area (200) through a transport system (300); Step 2: introducing N2 to purge the source region (100) and the epitaxial growth region (200). After the purge is completed, the gas flow shutoff valve (106) is closed; Step 3: heating the epitaxial growth region (200) by means of a heating component on the epitaxial growth region (200) and maintaining the temperature at 900°C±10°C; maintaining the pressure of the epitaxial growth region (200) at 600mbar±10mbar by means of a tail exhaust system (400); In the fourth step, a TMGa precursor, O2 and a doping gas are introduced into the epitaxial growth region (200), and O2 reacts with the TMGa precursor to generate Ga2O3, which is then deposited on the surface of the substrate (1) to form a thin film.

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