Vertical low pressure chemical vapor deposition (LPCVD) gallium oxide epitaxial device and gallium oxide thin film preparation process

Abstract

The invention discloses a vertical low pressure chemical vapor deposition (LPCVD) gallium oxide epitaxial device and a gallium oxide thin film preparation process. The vertical LPCVD gallium oxide epitaxial device comprises a source region, an epitaxial growth region, a tail exhaust system and a cooling system, the source region and the epitaxial growth region are both of a cylindrical structure, the source region and the epitaxial growth region are detachably connected in a sealed mode, a gallium boat used for containing Ga metal is arranged in the source region, the source region is used for heating the Ga metal and conveying Ga-containing steam into the epitaxial growth region, and the epitaxial growth region is used for plating a gallium oxide thin film on the surface of a substrate; a plurality of gas inlet pipelines penetrate through the source region in a sealing manner and then extend to the gas inlet end of the epitaxial growth region, so that process gas is conveyed into the epitaxial growth region, the exhaust end of the epitaxial growth region is connected with a tail exhaust system, and the tail exhaust system is used for exhausting waste gas in the epitaxial growth region; 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 maintenance, high reliability and the like, and the quality of the gallium oxide epitaxial layer is improved.

Description

Technical Field

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

[0002] Gallium oxide (Ga 2 O 3 ) 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. Gallium oxide has 5 crystal structures, of which β-Ga is grown by melt method. 2 O 3 , and β-Ga 2 O 3 It 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] At present, the existing technologies for preparing gallium oxide epitaxial materials include MBE, HVPE, OVPE, LPCVD, MOCVD, Mist-CVD, etc. At present, the technologies for preparing gallium oxide epitaxial materials at home and abroad include MBE, HVPE, MOCVD, Mist-CVD and LPCVD. The MBE method has a very low deposition rate, is expensive, and has a very high vacuum requirement. 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 is mainly used for α-Ga 2 O 3The epitaxial growth of the HVPE method has limited application areas and is difficult to promote on a large scale. The HVPE method cannot perform thin film epitaxy of lateral devices. The surface roughness of thick epitaxial thin films is relatively large. CMP polishing is required after epitaxy, and uncontrollable doping of Si elements is prone to occur, affecting the stability and reliability of the device. The MOCVD method equipment is relatively complex and expensive. Commonly used gallium sources such as trimethylgallium (TMGa) or triethylgallium (TEGa) are 5 to 10 times more expensive than metal gallium. The raw material utilization efficiency in the epitaxial process is low, so the process cost is relatively high. Figure 1 As shown in the figure, the existing LPCVD method generally adopts a quartz inner tube structure, which is prone to uncontrollable Si element doping. In addition, because the Ga source is supplied in the form of Ga vapor, it reacts quickly with oxygen sources such as oxygen, the growth rate is difficult to control, and it is easy to generate Ga on the substrate surface. 2 O 3 Powder, resulting in low epitaxial yield. Summary of the invention

[0005] The technical problem to be solved by the present invention is to solve the problem that the uncontrollable doping of Si elements, the excessively fast growth rate, and the easy generation of Ga on the substrate surface in the current gallium oxide LPCVD epitaxial process are easy to occur. 2 O 3 In order to solve the problems of powder and the like, a vertical LPCVD gallium oxide epitaxial device and a gallium oxide thin film preparation process are provided which has a compact structure, is easy to operate and has high stability.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A vertical LPCVD gallium oxide epitaxial device comprises: a source region, an epitaxial growth region, a tail exhaust system and a cooling system; the source region and the epitaxial growth region both adopt a cylindrical structure, and the source region and the epitaxial growth region are detachably sealed and connected, a gallium boat for containing Ga metal is provided in the source region, the source region is used to heat Ga metal and transport Ga vapor to the epitaxial growth region, and the epitaxial growth region is used to plate a gallium oxide film on the surface of a substrate; a plurality of air intake pipes are sealed and penetrate the source region and then extend to the air intake end of the epitaxial growth region to transport process gases to the epitaxial growth region, the exhaust end of the epitaxial growth region is connected to the tail exhaust system, 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 cool the source region, the epitaxial growth region and the tail exhaust system.

[0008] As a further improvement of the present invention, a transmission mechanism is provided through the seal in the epitaxial growth zone, and the transmission mechanism is located at the exhaust end of the epitaxial growth zone. The transmission mechanism is used to absorb the substrate and drive the substrate to rise, fall and rotate in the epitaxial growth zone.

[0009] As a further improvement of the present invention, the transmission mechanism includes an electrostatic chuck and a motor, wherein the motor is arranged outside the epitaxial growth zone, and the transmission shaft seal of the motor passes through the air inlet end of the epitaxial growth zone and extends into the epitaxial growth zone. An electrostatic chuck is provided at the end of the transmission shaft, and the electrostatic chuck is used to adsorb the substrate to realize the inversion of the substrate in the epitaxial growth zone.

[0010] As a further improvement of the present invention, the multiple air intake pipes are respectively connected to the doping source, the oxygen source and the N 2 / Ar source, and at least one extended gas delivery pipe is reserved at the gas inlet end of the epitaxial growth zone.

[0011] As a further improvement of the present invention, a uniform flow component is provided at the gas inlet end of the epitaxial growth zone, and the uniform flow component is connected to the source zone and the gas delivery pipe to achieve uniform distribution of the process gas in the epitaxial growth zone.

[0012] As a further improvement of the present invention, the source region and the epitaxial growth region are both formed by nesting an outer wall chamber and an inner wall chamber, and the connection between the source region and the epitaxial growth region is detachably connected in the form of a combination of a locking cylinder and a sealing ring.

[0013] As a further improvement of the present invention, a resistance heating component is provided between the outer wall chamber and the inner wall chamber to achieve uniform heating of the source region and the epitaxial growth region.

[0014] As a further improvement of the present invention, the outer wall chamber adopts a double-layer water-cooling structure, and the double-layer water-cooling structure is connected to the cooling system.

[0015] As a further improvement of the present invention, a temperature measuring component is provided between the outer wall chamber and the inner wall chamber, and the temperature measuring component includes a thyristor, a temperature control meter and a temperature measuring element. The temperature measuring element is used to measure the process temperature between the outer wall chamber and the inner wall chamber in real time. The temperature control meter is used to read the data collected by the temperature measuring element and transmit the data to a remote host computer. The remote host computer reads the temperature value in real time and adjusts the power input by the thyristor in the resistance heating according to the temperature deviation, so as to control the heating power of the resistance heating component.

[0016] As a general technical concept, the present invention also provides a gallium oxide thin film preparation process based on the above-mentioned vertical LPCVD gallium oxide epitaxial device, comprising the following steps:

[0017] The first step is to introduce N into the source region and the epitaxial growth region. 2 or Ar for purging, then separate the source region and the epitaxial growth region, place the substrate in the epitaxial growth region, and fix it on the electrostatic chuck, seal and merge the source region and the epitaxial growth region, and then introduce N 2 Or Ar for purging;

[0018] The second step is to heat the source area and keep it at 900℃±10℃ through the resistance heating component, and the metal Ga in the gallium boat forms Ga vapor; the resistance heating component heats the epitaxial growth area and keeps it at 1100℃±10℃, and the pressure of the epitaxial growth area is maintained at 50Pa±5Pa through the tail exhaust system;

[0019] Step 3: Introduce N into the air inlet of the source area. 2 Or Ar as a carrier gas to carry Ga vapor into the epitaxial growth region;

[0020] Step 4: Introduce O into the epitaxial growth region 2 and doping gas, O 2 Reacts with Ga vapor to generate Ga 2 O 3 , Ga 2 O 3 Deposited onto the substrate surface to form a thin film.

[0021] Compared with the prior art, the advantages of the present invention are:

[0022] 1. In the vertical LPCVD gallium oxide epitaxial device of the present invention, the reaction chamber of the device is divided into two sections as a whole. The upper section is a growth area for epitaxial growth process, and the lower section is a source area for supplying reaction gas. The lower section can be raised and lowered by a motor and a guide rail, and the two sections are tightly connected at the joint by a locking cylinder and a sealing ring. When the two sections are separated, it is convenient to disassemble and maintain the components inside the reaction chamber. Specifically, by setting the source area and the epitaxial growth area as cylindrical structures, and the source area and the epitaxial growth area are connected by a detachable seal, the source area is used to heat Ga metal and transport Ga vapor to the epitaxial growth area, and the substrate is placed in the epitaxial growth area for epitaxial process, which greatly reduces the complexity of the equipment, makes maintenance easier, and makes it simpler and faster to take and put the substrate.

[0023] 2. The vertical LPCVD gallium oxide epitaxial device of the present invention realizes the inversion of the substrate in the epitaxial growth area through the transmission mechanism, which greatly reduces the accumulation of Ga on the substrate surface commonly seen in the LPCVD process. 2 O 3 Particles effectively reduce particulate pollution and significantly improve epitaxial yield.

[0024] 3. In the gallium oxide thin film preparation process of the present invention, during the epitaxial growth process, the distance between the substrate and the uniform flow assembly is kept fixed according to the setting value before the process starts, and the carrier gas N supplied in the source region is adjusted. 2 and N provided in the current equalization component 2 The flow rate can dilute the generated Ga vapor for the second time, thereby regulating the Ga vapor supply and achieving a slower Ga 2 O 3The reaction speed is improved, and the motor always keeps rotating at a constant speed, which improves the thickness uniformity of the gallium oxide film. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the principle of the LPCVD process in the prior art;

[0026] Figure 2 It is a schematic diagram of the structural principle of a vertical LPCVD gallium oxide epitaxial device in a specific embodiment of the present invention;

[0027] Figure 3 This is a process flow chart of preparing a gallium oxide thin film in a specific embodiment of the present invention;

[0028] Legend: 1. Substrate; 100. Source region; 101. Gallium boat; 102. Outer wall chamber; 103. Inner wall chamber; 104. Resistance heating assembly; 105. SCR; 106. Temperature controller; 107. Temperature measuring element; 200. Epitaxial growth region; 201. Flow-uniform assembly; 300. Transmission mechanism; 301. Electrostatic chuck; 302. Motor; 400. Exhaust system; 401. Exhaust duct; 500. Exhaust processor; 600. Cooling system. DETAILED DESCRIPTION

[0029] 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.

[0030] 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.

[0031] 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.

[0032] Example

[0033] like Figure 2As shown, the vertical LPCVD gallium oxide epitaxial device of the present invention comprises: a source region 100, an epitaxial growth region 200, a tail exhaust system 400 and a cooling system 600. The source region 100 and the epitaxial growth region 200 both adopt a cylindrical structure, and the source region 100 and the epitaxial growth region 200 are connected in a detachable sealed manner. A gallium boat 101 for holding Ga metal is provided in the source region 100. The gallium metal evaporates under heating to form Ga vapor. The source region 100 transports the Ga vapor to the epitaxial growth region 200. The epitaxial growth region 200 is used to realize the coating of a gallium oxide film on the surface of the substrate 1. A plurality of air inlet pipes are sealed and penetrate the source region 100 and then extend to the air inlet end of the epitaxial growth region 200 to realize the delivery of process gases to the epitaxial growth region 200. Specifically, the plurality of air inlet pipes are respectively connected to the doping source, the oxygen source and the N2 / Ar source, and at least one extended gas delivery pipe is reserved at the air inlet end of the epitaxial growth region 200 to facilitate process expansion. The exhaust end of the epitaxial growth zone 200 is connected to the tail exhaust system 400, which is used to discharge the exhaust gas in the epitaxial growth zone 200 and transport it to the tail gas processor 500 for treatment before discharge. In this embodiment, the top of the epitaxial growth zone 200 is an annular tail gas discharge port, which is connected to the exhaust pipe 401 to discharge the reaction by-products and residual reaction gases to the tail gas processor 500. The cooling system 600 is respectively connected to the source area 100, the epitaxial growth zone 200 and the tail exhaust system 400 to achieve cooling of the source area 100, the epitaxial growth zone 200 and the tail exhaust system 400. 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. In this embodiment, an electronic control system can also be provided to realize automatic control of the whole machine and safe start and stop operations.

[0034] In the present embodiment, the reaction chamber part of the epitaxial device is divided into two sections as a whole. The upper section is the epitaxial growth zone 200 for epitaxial growth process, and the lower section is the source zone 100 for supplying gallium gas. The lower section can be raised and lowered by a motor and a guide rail, and the two sections are tightly connected at the joint by a locking cylinder and a sealing ring. When the two sections are separated, it is convenient to disassemble and maintain the components inside the reaction chamber. Specifically, by setting the source zone 100 and the epitaxial growth zone 200 as cylindrical structures, and the source zone 100 and the epitaxial growth zone 200 are connected by a detachable seal, the source zone 100 is used to heat Ga metal and transport Ga vapor to the epitaxial growth zone 200, and the substrate 1 is placed in the epitaxial growth zone 200 for epitaxial process, which greatly reduces the complexity of the equipment, makes maintenance easier, and makes it simpler and faster to take and put the wafers.

[0035] In this embodiment, the gas inlet end of the source region 100 is connected to the N 2 In the epitaxial device, the gas inlet pipes of the source area 100 and the epitaxial growth area 200 can provide N 2 / Ar is supplied to the epitaxial growth zone 200. After the gallium vapor is diluted once in the source zone 100, it can be diluted again when entering the epitaxial growth zone 200. The supply of gallium vapor has a double dilution function, which is more rapid and uncontrollable than the reaction rate in the conventional LPCVD process. It is beneficial to achieve a slowly controllable epitaxial rate and improve the quality of gallium oxide epitaxy.

[0036] like Figure 2 As shown, the source region 100 and the epitaxial growth region 200 are both formed by nesting the outer wall chamber 102 and the inner wall chamber 103, and the connection between the source region 100 and the epitaxial growth region 200 is detachably connected in the form of a locking cylinder and a sealing ring combination, which has the characteristics of simple structure, convenient operation and high sealing performance, and is simple and fast to take and put the wafer. 2 , H 2 O、Cl 2 The material that reacts with HCl, etc. is preferably a high-purity SiC material and a high-purity SiC coating or a TaC coating graphite material. Other materials that have heating and heat preservation functions and do not react with the process gas can also be selected. The outer wall chamber 102 is made of metal and has sufficient strength to support the weight of the materials in the inner wall chamber 103.

[0037] like Figure 2 As shown, a transmission mechanism 300 is provided through the top seal of the epitaxial growth zone 200 . The transmission mechanism 300 is located at the exhaust end of the epitaxial growth zone 200 . The transmission mechanism 300 is used to absorb the substrate 1 and drive the substrate 1 to rise, fall and rotate in the epitaxial growth zone 200 .

[0038] like Figure 2 As shown, the transmission mechanism 300 includes an electrostatic chuck 301 and a motor 302. The motor 302 is arranged outside the epitaxial growth region 200, and the transmission shaft of the motor 302 passes through the air inlet end of the epitaxial growth region 200 in a magnetic fluid sealing manner and then extends into the epitaxial growth region 200. The end of the transmission shaft is provided with an electrostatic chuck 301, and the electrostatic chuck 301 is used to adsorb the substrate 1 so as to realize that the substrate 1 is inverted in the epitaxial growth region 200.

[0039] During the epitaxial process, the substrate 1 is adsorbed on the electrostatic chuck 301, which is connected to the drive shaft of the motor 302. The drive shaft of the motor 302 is sealed with the epitaxial growth zone 200 by a magnetic fluid. The motor 302 realizes the lifting and rotating functions 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. In addition, since the traditional quartz inner tube and quartz substrate base or graphite base are not used, but the electrostatic chuck 301 and the inner wall chamber of SiC material are used, the unintentional doping of elements such as Si and C is effectively avoided. By inverting the substrate 1, the Ga deposited on the surface of the substrate 1 is greatly reduced. 2 O 3The powder can reduce the pollution of dropped objects falling on the surface of the substrate 1, and effectively improve the epitaxial yield.

[0040] like Figure 2 As shown, a uniform flow component 201 is provided at the gas inlet end of the epitaxial growth region 200, and the uniform flow component 201 is connected to the source region 100 and the gas delivery pipe, and all reaction gases enter from the uniform flow component 201 and are evenly mixed before being delivered to the surface of the substrate 1, so as to achieve uniform distribution of process gases in the epitaxial growth region 200. The uniform flow component 201 can specifically be in the form of a combination of a uniform flow plate and a shower plate to improve the uniformity of gas distribution.

[0041] In this embodiment, the motor 302 can realize the lifting function, and the distance between the substrate 1 and the uniform flow component 201 can be adjusted, which helps to control the concentration of the reaction gas from the inlet to the outlet due to the close or long stroke, thereby further optimizing the process uniformity and doping concentration uniformity.

[0042] like Figure 2 As shown, a resistance heating assembly 104 is provided between the outer wall chamber 102 and the inner wall chamber 103 to achieve uniform heating of the source region 100 and the epitaxial growth region 200 .

[0043] In this embodiment, the outer wall chamber 102 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 source region 100 and the epitaxial growth region 200 .

[0044] like Figure 2 As shown, a temperature measuring component is provided between the outer wall chamber 102 and the inner wall chamber 103, and the temperature measuring component includes a thyristor 105, a temperature control meter 106 and a temperature measuring element 107. The temperature measuring element 107 is used to measure the process temperature between the outer wall chamber 102 and the inner wall chamber 103 in real time. The temperature control meter 106 is used to read the data collected by the temperature measuring element 107 and transmit the data to a remote host computer. The remote host computer reads the temperature value in real time and adjusts the power input by the thyristor 105 in the resistance heating according to the temperature deviation to control the heating power of the resistance heating component 104. The source area 100 is uniformly controllable in a wide temperature range of 550°C to 1100°C, and the epitaxial growth area 200 is uniformly controllable in a wide temperature range of 900°C to 1400°C, and the temperature uniformity is ≤±0.5°C, thereby realizing the precise control of the epitaxial reaction temperature and improving the process stability.

[0045] In this embodiment, the tail exhaust system 400 includes a dry pump and an exhaust pipe 401 with a butterfly valve, the connecting pipe is connected to the cooling system 600, one end of the exhaust pipe 401 is connected to the dry pump, and the other end of the exhaust pipe 401 is connected to the exhaust end of 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 exhaust pipe 401 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. Since the by-products of the LPCVD process contain dust, in order to improve the operating stability of the dry pump, a filter can be set in the exhaust pipe 401, and the exhaust gas discharged from the epitaxial growth area 200 enters the dry pump after filtering.

[0046] like Figure 3 As shown, this embodiment also provides a gallium oxide thin film preparation process based on the above-mentioned vertical LPCVD gallium oxide epitaxial device, comprising the following steps:

[0047] The first step is to introduce N into the source region 100 and the epitaxial growth region 200. 2 Or Ar is used for purging to remove impurities after the previous process or maintenance; then the source region 100 and the epitaxial growth region 200 are separated, the substrate 1 is placed in the epitaxial growth region 200 and fixed on the electrostatic chuck 301, and then the source region 100 and the epitaxial growth region 200 are sealed and merged, and N2 or Ar is introduced again for purging.

[0048] Step 2: After the purging is completed, the source area and the growth area are heated simultaneously; the source area 100 is heated and maintained at 900°C by the resistance heating component 104, and the metal Ga in the gallium boat 101 forms Ga vapor; the resistance heating component 104 heats and maintains the epitaxial growth area 200 at 1100°C, and the pressure of the epitaxial growth area 200 is maintained at 50Pa by the tail exhaust system 400.

[0049] Step 3: N is introduced into the air inlet of the source region 100. 2 Or Ar is used as a carrier gas to carry Ga vapor into the epitaxial growth region 200 .

[0050] Step 4: introducing O into the epitaxial growth region 200 2 and doping gas, O 2 Reacts with Ga vapor to generate Ga 2 O 3 , Ga 2 O 3 Deposited onto the surface of substrate 1 to form a thin film.

[0051] During the epitaxial growth process, the distance between the substrate 1 and the flow-uniform assembly 201 is kept constant according to the setting value before the process starts. By adjusting the carrier gas N supplied in the source region 100,2 and N provided in the flow equalization component 201 2 The flow rate can dilute the generated Ga vapor for the second time, thereby regulating the Ga vapor supply and achieving a slower Ga 2 O 3 The reaction speed is improved, and the motor 302 always keeps rotating at a constant speed, thereby improving the thickness uniformity of the gallium oxide film.

[0052] 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 vertical LPCVD gallium oxide epitaxial device, characterized in that: include: A source region (100), an epitaxial growth region (200), a tail exhaust system (400) and a cooling system (600); the source region (100) and the epitaxial growth region (200) both adopt a cylindrical structure, and the source region (100) and the epitaxial growth region (200) are detachably sealed and connected; a gallium boat (101) for containing Ga metal is provided in the source region (100); the source region (100) is used to heat the Ga metal and transport Ga vapor to the epitaxial growth region (200); the epitaxial growth region (200) is used to plate a gallium oxide film on the surface of a substrate (1); An air intake pipe is sealed and penetrates the source region (100) and then extends to the air intake end of the epitaxial growth region (200) to realize the delivery of process gas into the epitaxial growth region (200); the exhaust end of the epitaxial growth region (200) is connected to a tail exhaust system (400), and the tail exhaust system (400) is used to exhaust the waste gas in the epitaxial growth region (200); the cooling system (600) is respectively connected to the source region (100), the epitaxial growth region (200) and the tail exhaust system (400) to realize the cooling of the source region (100), the epitaxial growth region (200) and the tail exhaust system (400).

2. The vertical LPCVD gallium oxide epitaxial device according to claim 1, characterized in that: A transmission mechanism (300) is provided in a sealed manner throughout the epitaxial growth region (200). The transmission mechanism (300) is located at the exhaust end of the epitaxial growth region (200). The transmission mechanism (300) is used to absorb the substrate (1) and drive the substrate (1) to rise, fall and rotate in the epitaxial growth region (200).

3. The vertical LPCVD gallium oxide epitaxial device according to claim 2, characterized in that: The transmission mechanism (300) comprises an electrostatic chuck (301) and a motor (302); the motor (302) is arranged outside the epitaxial growth region (200); a transmission shaft seal of the motor (302) penetrates through the air inlet end of the epitaxial growth region (200) and then extends into the epitaxial growth region (200); an electrostatic chuck (301) is arranged at the end of the transmission shaft; the electrostatic chuck (301) is used to adsorb the substrate (1) so as to achieve inversion of the substrate (1) in the epitaxial growth region (200).

4. The vertical LPCVD gallium oxide epitaxial device according to claim 2, characterized in that: The multiple gas inlet pipes are respectively connected to a doping source, an oxygen 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).

5. The vertical LPCVD gallium oxide epitaxial device according to claim 4, characterized in that: A uniform flow component (201) is provided at the gas inlet end of the epitaxial growth region (200), and the uniform flow component (201) is connected to the source region (100) and the gas delivery pipe to achieve uniform distribution of process gas in the epitaxial growth region (200).

6. The vertical LPCVD gallium oxide epitaxial device according to any one of claims 1 to 5, characterized in that: The source region (100) and the epitaxial growth region (200) are both formed by nesting an outer wall chamber (102) and an inner wall chamber (103), and the connection between the source region (100) and the epitaxial growth region (200) is detachably connected in the form of a combination of a locking cylinder and a sealing ring.

7. The vertical LPCVD gallium oxide epitaxial device according to claim 6, characterized in that: A resistance heating component (104) is provided between the outer wall chamber (102) and the inner wall chamber (103) to achieve uniform heating of the source region (100) and the epitaxial growth region (200).

8. The vertical LPCVD gallium oxide epitaxial device according to claim 6, characterized in that: The outer wall chamber (102) adopts a double-layer water-cooling structure, and the double-layer water-cooling structure is connected to the cooling system (600).

9. The vertical LPCVD gallium oxide epitaxial device according to claim 6, characterized in that: A temperature measuring component is provided between the outer wall chamber (102) and the inner wall chamber (103), the temperature measuring component comprising a thyristor (105), a temperature control meter (106) and a temperature measuring element (107), the temperature measuring element (107) being used to measure the process temperature between the outer wall chamber (102) and the inner wall chamber (103) in real time, the temperature control meter (106) being used to read data collected by the temperature measuring element (107) and transmit the data to a remote host computer, the remote host computer reading the temperature value in real time and adjusting the power input by the thyristor (105) according to the temperature deviation, thereby controlling the heating power of the resistance heating component (104).

10. A process for preparing a gallium oxide thin film based on the vertical LPCVD gallium oxide epitaxial device according to any one of claims 1 to 9, characterized in that: The following steps are involved: The first step is to introduce N2 or Ar into the source region (100) and the epitaxial growth region (200) for purging, then separate the source region (100) and the epitaxial growth region (200), place the substrate (1) into the epitaxial growth region (200), and fix it on the electrostatic chuck (301), seal and merge the source region (100) and the epitaxial growth region (200), and introduce N2 or Ar again for purging; Step 2: The source region (100) is heated and maintained at 900°C±10°C by a resistance heating component (104), and the metal Ga in the gallium boat (101) forms Ga vapor; the resistance heating component (104) heats and maintains the epitaxial growth region (200) at 1100°C±10°C, and the pressure of the epitaxial growth region (200) is maintained at 50Pa±5Pa by a tail exhaust system (400); Step 3: introducing N2 or Ar as a carrier gas at the gas inlet end of the source region (100) to carry Ga vapor into the epitaxial growth region (200); Step 4: 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.

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