Hydride vapor phase epitaxial growth system and method for epitaxial growth of gallium oxide

Abstract

The invention belongs to the technical field of single crystal epitaxy, and particularly relates to a hydride vapor phase epitaxial growth system and method for gallium oxide epitaxial growth. The specifically designed containing device is introduced into the growth system, the containing device and the substrate form the closed cavity, and the closed cavity is in negative pressure through the flow velocity design of the gas inlet and the gas outlet of the containing device, so that the substrate is sucked on the containing device, the back surface of the substrate is completely isolated from the reaction gas in the reaction chamber, and the reaction time is shortened. The formation of a gallium oxide epitaxial layer on the back surface of the substrate is avoided, and the yield of workpieces is improved. The gas inlet and the gas outlet are formed in the side wall and the bottom of the containing device respectively, gas in the closed cavity enters and exits, the influence of gas in the reaction chamber on the containing device is avoided, it is guaranteed that the back face of the substrate is not influenced by the gas in the reaction chamber, and the operation stability and repeatability are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of single crystal epitaxy, and particularly to a hydride vapor phase epitaxy growth system and method for gallium oxide epitaxial growth. Background Art

[0002] Gallium oxide (Ga2O3) is a super wide bandgap semiconductor material with a bandgap width of about 4.5 - 4.9 eV. Due to its excellent electrical and optical properties, such as high breakdown electric field, low conduction loss, and high thermal stability, it has broad application potential in the fields of power electronic devices (such as high-voltage power transistors, Schottky diodes) and ultraviolet light detectors.

[0003] Among the numerous growth methods of gallium oxide, the hydride vapor phase epitaxy (HVPE) technology has become an important research direction in recent years due to its high growth rate and the ability to prepare high-quality thick films. However, during the growth process, the precursor gas sometimes diffuses to the back side of the substrate and uncontrolled deposition occurs on the back side, resulting in a low yield of workpieces. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a hydride vapor phase epitaxy growth system and method for gallium oxide epitaxial growth. During the gallium oxide epitaxial growth process, the hydride vapor phase epitaxy growth system for gallium oxide epitaxial growth provided by the present invention can inhibit the growth of gallium oxide on the back side of the substrate and improve the yield of workpieces.

[0005] To achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0006] The present invention provides a hydride vapor phase epitaxy growth system for gallium oxide epitaxial growth, including a reaction chamber;

[0007] A holding device, which is located at the lower side inside the reaction chamber and is used to place the substrate; the shape of the holding device is a groove; several support protrusions are arranged on the lower side inside the open side of the holding device, and the support protrusions are used to support the substrate; a sealed cavity is formed between the holding device and the substrate; a gas inlet is arranged on the side wall of the holding device; the gas inlet is located on the side wall between the support protrusion and the bottom of the holding device; a gas outlet is arranged at the bottom of the holding device;

[0008] A nozzle, which is arranged on the upper side inside the reaction chamber and is located directly above the holding device;

[0009] A gallium boat, which is placed above the nozzle;

[0010] A gas passage, which is located above the gallium boat;

[0011] The first annular gas path, the second annular gas path and the third annular gas path, and the first annular gas path, the second annular gas path and the third annular gas path are sequentially arranged around the nozzle from near to far;

[0012] A heating unit, and the heating unit is sleeved outside the reaction chamber.

[0013] Preferably, the number of the gas inlets is 2.

[0014] Preferably, the front side of the substrate faces upward, and the front side of the substrate is flush with the open side of the holding device.

[0015] Preferably, a rotating unit is included, the holding device is placed on the rotating unit, and the rotating unit realizes the rotation of the holding device.

[0016] The present invention also provides a method for growing gallium oxide epitaxially by using the hydride vapor phase epitaxy growth system according to the above technical solution, including the following steps:

[0017] Place the substrate on the support convex of the holding device; control the gas flow rates of the gas inlet and the gas outlet of the holding device so that the sealed cavity formed by the holding device and the substrate is in a negative pressure; the front side of the substrate faces upward;

[0018] Introduce a protective gas through the first annular gas path and the third annular gas path to purge and evacuate the air in the reaction chamber;

[0019] After the reaction chamber is evacuated, use the heating unit to heat the reaction chamber to the growth temperature, then introduce hydrogen chloride through the gas passage, hydrogen chloride contacts with the gallium boat to generate gallium chloride, the hydrogen chloride is introduced into the reaction chamber through the nozzle, and oxygen is introduced through the second annular gas path to realize the epitaxial growth of gallium oxide on the substrate.

[0020] Preferably, the gas at the gas inlet of the holding device includes nitrogen and / or argon; the negative pressure is less than or equal to 100-200 Torr.

[0021] Preferably, the protective gas includes one or more of nitrogen, argon and helium, and the flow rate of the protective gas in the first annular gas path and the second annular gas path is 10-10000 sccm;

[0022] The degree of vacuum of the evacuation is less than or equal to 20 Pa.

[0023] Preferably, the heating rate of temperature rise is 1-10 °C / min; the growth temperature is 900-1050 °C.

[0024] Preferably, the flow rate of the hydrogen chloride is 20-200 sccm; the flow rate of the oxygen is 100-1000 sccm.

[0025] Preferably, the pressure for the epitaxial growth is 100 to 500 Torr.

[0026] The present invention provides a hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth.

[0027] 1. The present invention introduces a specifically designed holding device into the hydride vapor phase epitaxial growth system. The holding device and the substrate form a sealed cavity. Through the flow rate design of the gas inlet and gas outlet of the holding device, the sealed cavity is in a negative pressure state, so that the substrate is adsorbed on the holding device, and the back surface of the substrate is completely isolated from the reaction gas in the reaction chamber, avoiding the formation of a gallium oxide epitaxial layer on the back surface of the substrate and improving the yield of the workpiece.

[0028] 2. The side wall and bottom of the holding device are respectively provided with a gas inlet and a gas outlet, and the gas in the sealed cavity enters and exits, avoiding the influence of the gas in the reaction chamber on the holding device, ensuring that the back surface of the substrate is not affected by the gas in the reaction chamber, and improving the stability and repeatability of the operation.

[0029] 3. The present invention provides a plurality of support protrusions on the lower side inside the open side of the holding device, and the support protrusions are used to support the substrate: the design of the support protrusions ensures the stable placement of the substrate, avoids its offset under high temperature conditions, and realizes uniform and high-quality gallium oxide epitaxial layer growth.

[0030] 4. The shape of the holding device of the present invention can be adjusted according to the shape of the substrate to meet the epitaxial requirements of substrates with different sizes and shapes.

[0031] The present invention also provides a method for gallium oxide epitaxial growth using the hydride vapor phase epitaxial growth system described in the above technical solution. The method of the present invention can inhibit the growth of the gallium oxide epitaxial layer on the back surface of the substrate and improve the yield of the gallium oxide epitaxial wafer.

[0032] Furthermore, the present invention controls the introduction flow rates of the protective gas and the reaction gas during the epitaxial growth process, ensuring good growth of gallium oxide on the front surface of the substrate and resulting in a gallium oxide epitaxial layer with small defects on the front surface of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of the hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention;

[0034] Figure 2 Schematic diagram of the structure of the holding device in the hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention;

[0035] Figure 3 OM images of the back surfaces of the finished products obtained in Example 1 and Comparative Examples 1 to 3;

[0036] Figure 4 It is the characterization result of the swing test curve on the front side of the finished product obtained in Example 1. Detailed implementation manners

[0037] Figure 1 It is a schematic diagram of a hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention; hereinafter, in conjunction with Figure 1 The structure of the hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention will be described in detail.

[0038] The present invention provides a hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth, including a reaction chamber;

[0039] A holding device, the holding device is located at the lower side inside the reaction chamber, and the holding device is used for placing a substrate; the shape of the holding device is a groove; several support protrusions are arranged on the lower side inside the open side of the holding device, and the support protrusions are used for supporting the substrate; a sealed cavity is formed between the holding device and the substrate; a gas inlet is arranged on the side wall of the holding device; the gas inlet is located on the side wall between the support protrusion and the bottom of the holding device; a gas outlet is arranged at the bottom of the holding device;

[0040] A nozzle, the nozzle is arranged on the upper side inside the reaction chamber and is located directly above the holding device;

[0041] A gallium boat, the gallium boat is placed above the nozzle;

[0042] A gas passage, the gas passage is located above the gallium boat;

[0043] A first annular gas path, a second annular gas path and a third annular gas path, the first annular gas path, the second annular gas path and the third annular gas path are arranged around the nozzle;

[0044] A heating unit, the heating unit is sleeved outside the reaction chamber.

[0045] The hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention includes a reaction chamber, and the material of the reaction chamber is preferably quartz. In the present invention, the cross-sectional shape of the reaction chamber is preferably circular. In the present invention, a wafer taking port and an exhaust port are preferably arranged at the bottom of the reaction chamber. In the present invention, a vacuum pump is preferably arranged at the exhaust port, and the vacuum pump is used to control the pressure of the reaction chamber. In the present invention, the wafer taking port is used to take out the gallium oxide epitaxial wafer.

[0046] The hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention includes a holding device, which is located at the lower side inside the reaction chamber and is used to place a substrate. In the present invention, the material of the holding device is preferably graphite, and the surface of the graphite is preferably coated with a silicon carbide coating. In the present invention, the shape of the holding device is a groove, which specifically refers to a container with one open side formed by a bottom surface and side walls. In the present invention, the shape of the cross-section of the holding device is preferably adjusted according to the shape of the substrate. In a specific embodiment of the present invention, the cross-sectional shape of the holding device is specifically preferably circular or square, and more preferably circular; in the present invention, when the cross-sectional shape of the holding device is preferably circular, the structural schematic diagram of the holding device is as shown in Figure 2 shown. In the present invention, a plurality of support protrusions are provided on the lower side inside the open side of the holding device, and the support protrusions are used to support the substrate; so that a sealed cavity is formed between the holding device and the substrate. In the present invention, a gas inlet is provided on the side wall of the holding device, and the gas inlet is located on the side wall between the support protrusion and the bottom of the holding device; the number of gas inlets is preferably 2, and the 2 gas inlets are preferably arranged opposite to each other. In the present invention, a gas outlet is provided at the bottom of the holding device, and a vacuum pump is preferably provided at the gas outlet, and the vacuum pump is used to control the pressure of the sealed cavity. In the present invention, when the substrate is placed, the front side is facing up, and the front side of the substrate is preferably flush with the open side of the holding device.

[0047] The hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention preferably further includes a rotation unit, and the holding device is preferably placed on the rotation unit, and the rotation unit realizes the rotation of the holding device to realize the uniform growth of gallium oxide on the substrate.

[0048] The hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention includes a nozzle, which is arranged on the upper side inside the reaction chamber and is located directly above the holding device. In the present invention, the nozzle is used to introduce gallium chloride formed by the working gas hydrogen chloride and gallium into the reaction chamber.

[0049] The hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention includes a gallium boat, which is placed above the nozzle, and the gallium boat is used to provide a gallium source.

[0050] The hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention includes a gas passage, which is located above the gallium boat. In the present invention, the gas passage can introduce hydrogen chloride and make the introduced hydrogen chloride contact with the gallium boat to react to form gallium chloride; the formed gallium chloride is ejected through the nozzle below the gallium boat.

[0051] The hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention includes a first annular gas path, a second annular gas path, and a third annular gas path. The first annular gas path, the second annular gas path, and the third annular gas path are sequentially arranged around the nozzle from near to far; that is, the distances of the first annular gas path, the second annular gas path, and the third annular gas path from the nozzle are the first annular gas path, the second annular gas path, and the third annular gas path in ascending order; the first annular gas path, the second annular gas path, and the third annular gas path are used to introduce protective gas and reaction gas into the reaction chamber.

[0052] The hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth provided by the present invention includes a heating unit, and the heating unit is sleeved outside the reaction chamber. In the present invention, the heating unit is used for heating the reaction chamber.

[0053] The present invention also provides a method for gallium oxide epitaxial growth using the hydride vapor phase epitaxial growth system described in the above technical solution, including the following steps:

[0054] Place the substrate on the support convex of the holding device; control the gas flow rates at the gas inlet and gas outlet of the holding device so that the closed cavity formed by the holding device and the substrate is in a negative pressure; the front side of the substrate faces upward.

[0055] Introduce protective gas through the first annular gas path and the third annular gas path to purge and evacuate the air in the reaction chamber.

[0056] After the reaction chamber is evacuated, use the heating unit to heat the reaction chamber to the growth temperature, then introduce hydrogen chloride through the gas passage. The hydrogen chloride contacts the gallium boat to generate gallium chloride. The hydrogen chloride is introduced into the reaction chamber through the nozzle, and oxygen is introduced through the second annular gas path to achieve the epitaxial growth of gallium oxide on the substrate.

[0057] The present invention places the substrate on the support convex of the holding device; controls the gas flow rates at the gas inlet and gas outlet of the holding device so that the closed cavity formed by the holding device and the substrate is in a negative pressure; the front side of the substrate faces upward.

[0058] In the present invention, the type of the substrate is preferably set according to actual needs, and specifically preferably: in the case of homoepitaxy, the substrate is preferably a substrate having a gallium oxide (010) crystal plane, a substrate having a (100) crystal plane or a substrate having a (001) crystal plane. In the present invention, the (010) crystal plane of the substrate having a gallium oxide (010) crystal plane is preferably prepared by a beveling process, the (100) crystal plane of the substrate having a (100) crystal plane is preferably prepared by a beveling process, and the (001) crystal plane of the substrate having a (001) crystal plane is preferably prepared by a beveling process. In the present invention, in the case of heteroepitaxy, the substrate is specifically preferably a sapphire (0001) substrate.

[0059] In the present invention, the formation of the substrate is preferably set according to actual needs, specifically preferably circular or square, and further preferably circular. The present invention does not specifically limit the diameter of the circle, as long as it can form a sealed cavity with the containing device. In the present invention, the substrate is preferably pretreated before use, and the pretreatment includes polishing and annealing in sequence. The polishing method is preferably CMP polishing; the present invention does not specifically limit the annealing operation, and the annealing operation well-known to those skilled in the art can be adopted.

[0060] In the present invention, the gas at the gas inlet of the containing device preferably includes nitrogen and / or argon, and further preferably nitrogen. In the present invention, the negative pressure is preferably less than or equal to 200 Torr, specifically preferably 10 Torr, 50 Torr, 100 Torr, 150 Torr or 200 Torr. In a specific embodiment of the present invention, the gas flow rate at the gas inlet of the containing device is preferably greater than or equal to 300 sccm, specifically preferably 300 - 800 sccm, specifically preferably 300 sccm, 400 sccm, 500 sccm, 600 sccm, 700 sccm or 800 sccm. The present invention does not specifically limit the gas flow rate at the gas outlet of the containing device, as long as the negative pressure in the sealed cavity formed by the containing device and the substrate is less than or equal to 200 Torr.

[0061] After the sealed cavity formed by the containing device and the substrate is under negative pressure, the present invention introduces a protective gas through the first annular gas path and the third annular gas path to purge and evacuate the air in the reaction chamber.

[0062] In the present invention, the protective gas preferably comprises one or more of nitrogen, argon and helium, and more preferably nitrogen. In the present invention, the flow rate of the protective gas in the first annular gas path and the third annular gas path is independently preferably 10 to 10000 sccm, specifically preferably 10 sccm, 50 sccm, 100 sccm, 200 sccm, 300 sccm, 400 sccm, 500 sccm, 600 sccm, 700 sccm, 800 sccm, 900 sccm, 1000 sccm, 2000 sccm, 3000 sccm, 4000 sccm, 5000 sccm, 6000 sccm, 7000 sccm, 8000 sccm, 9000 sccm or 10000 sccm.

[0063] In the present invention, the degree of vacuum for evacuation is preferably less than or equal to 20 Pa, and more preferably 10 Pa, 15 Pa or 20 Pa.

[0064] In the present invention, the protective gas in the first annular gas path and the third annular gas path remains in an open state during the epitaxial growth process.

[0065] In the present invention, the protective gas in the first annular gas path and the third annular gas path has two functions: First, to purge the air in the reaction chamber and evacuate the vacuum. Second, the protective gas acts as an insulating gas to isolate oxygen and hydrogen chloride, preventing the reaction of oxygen and hydrogen chloride gases before reaching the reaction chamber, thereby achieving the effect of flow field control.

[0066] After the reaction chamber is evacuated, in the present invention, the reaction chamber is heated to the growth temperature by the heating unit, and then hydrogen chloride is introduced through the gas passage. The hydrogen chloride contacts the gallium boat to generate gallium chloride. The hydrogen chloride is introduced into the reaction chamber through the nozzle, and oxygen is introduced through the second annular gas path to achieve the epitaxial growth of gallium oxide on the substrate.

[0067] In the present invention, the heating rate of temperature increase is preferably 1 to 10 °C / min, specifically preferably 1 °C / min, 2 °C / min, 3 °C / min, 4 °C / min, 5 °C / min, 6 °C / min, 7 °C / min, 8 °C / min, 9 °C / min or 10 °C / min.

[0068] In the present invention, the growth temperature is preferably 900 to 1050 °C, specifically preferably 900 °C, 950 °C, 1000 °C or 1050 °C.

[0069] In the present invention, the flow rate of the hydrogen chloride is preferably 20 to 200 sccm, specifically preferably 20 sccm, 30 sccm, 40 sccm, 50 sccm, 60 sccm, 70 sccm, 80 sccm, 90 sccm, 100 sccm, 110 sccm, 120 sccm, 130 sccm, 140 sccm, 150 sccm, 160 sccm, 170 sccm, 180 sccm, 190 sccm or 200 sccm.

[0070] In the present invention, the flow rate of the oxygen is preferably 100 to 1000 sccm, specifically preferably 100 sccm, 200 sccm, 300 sccm, 400 sccm, 500 sccm, 600 sccm, 700 sccm, 800 sccm, 900 sccm or 1000 sccm; the oxygen is preferably introduced by being carried by nitrogen.

[0071] In the present invention, the epitaxial growth is preferably carried out under the condition of rotation, and the rotation speed is preferably 10 to 30 rpm, specifically preferably 10 rpm, 20 rpm or 30 rpm.

[0072] In the present invention, the pressure of the epitaxial growth is preferably 100 to 500 torr, specifically preferably 100 torr, 150 torr, 200 torr, 250 torr, 300 torr, 350 torr, 400 torr, 450 torr or 500 torr. In the present invention, the pressure of the epitaxial growth specifically refers to the pressure of the reaction chamber during the process of epitaxial growth; the pressure of the epitaxial growth is preferably controlled by a vacuum pump at the bottom of the reaction chamber.

[0073] The present invention does not specifically limit the time of the epitaxial growth, and those skilled in the art can control it according to the thickness of the gallium oxide to be epitaxially grown as actually required.

[0074] After the epitaxial growth is completed, the present invention preferably stops the introduction of hydrogen chloride, gallium and oxygen, and closes the heating unit; uses the vacuum pump at the exhaust port of the reaction chamber to evacuate the reaction chamber to vacuum to discharge the unreacted reaction gases; continues to introduce the protective gas through the first annular gas path and the third annular gas path until the temperature and pressure drop to room temperature and atmospheric pressure, then closes the inlet, outlet and rotation unit of the holding device, takes out the holding device and the substrate through the wafer taking port, and finally removes the finished product from the holding device.

[0075] The following combines examples to detail the hydride vapor phase epitaxial growth system and method for gallium oxide epitaxial growth provided by the present invention, but they cannot be understood as limiting the protection scope of the present invention.

[0076] Comparative Example 1

[0077] This embodiment is carried out in the hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth shown in Figure 1 shown below.

[0078] Place a 2-inch gallium oxide substrate on the support convex of the Figure 2 shown holding device; the flow rate of nitrogen at both gas inlets of the holding device is 0 sccm; the front side of the substrate faces upward.

[0079] Introduce nitrogen through the first annular gas path and the third annular gas path. Among them, the flow rate of nitrogen in the first annular gas path is 2000 sccm, and the flow rate of nitrogen in the third annular gas path is 2000 sccm; purge and evacuate the air in the reaction chamber to make the pressure in the reaction chamber 10 Pa; at the same time, turn on the rotation unit to realize the rotation of the holding device, and the rotation speed of the rotation unit is set to 20 rppm.

[0080] After the purging is completed, use the heating unit to heat the reaction chamber at a rate of 5 °C / min. When the temperature of the reaction chamber reaches 1050 °C; introduce hydrogen chloride through the gas path so that hydrogen chloride contacts the gallium boat to react to generate gallium chloride (GaCl2). The gallium chloride sprays out from the nozzle, and oxygen is introduced through the second annular gas path for 3 h of gallium oxide epitaxial growth; control the pressure in the reaction chamber to be 450 Torr. Among them, the flow rate of hydrogen chloride is 20 sccm, and the flow rate of oxygen is 500 sccm.

[0081] After the epitaxial growth is completed, stop introducing hydrogen chloride and oxygen, and turn off the heating unit; continue to introduce the protective gas to pump the reaction chamber to 10 Pa to discharge the working gas; after cooling to room temperature and making the pressure in the reaction chamber normal pressure, close the gas inlet, gas outlet and rotation unit of the holding device, take out the holding device, and finally remove the finished product from the holding device.

[0082] Comparative Example 2

[0083] The difference from Comparative Example 1 is that the flow rate of nitrogen at both gas inlets of the holding device is 100 sccm, and the pressure in the sealed cavity formed by the holding device and the substrate is 450 Torr.

[0084] Comparative Example 3

[0085] The difference from Comparative Example 1 is that the flow rate of nitrogen at both gas inlets of the holding device is 200 sccm, and the pressure in the sealed cavity formed by the holding device and the substrate is 350 Torr.

[0086] Example 1

[0087] The differences from Comparative Example 1 are as follows: the nitrogen flow rates at the two gas inlets of the holding device are both 300 sccm, and the pressure in the sealed cavity formed by the holding device and the substrate is 200 Torr.

[0088] Figure 3 FIG. OM images of the back sides of the finished products obtained in Example 1 and Comparative Examples 1 to 3 are shown. From Figure 3 It can be seen that when the inlet gas flow rate of the holding device is 0 sccm, relatively serious deposition phenomena occur on the back side of the epitaxial wafer. Since the reaction gas flows into the holding device from the side wall during the growth process, some gaseous precursors are deposited uncontrollably on the back side of the epitaxial wafer. As the inlet gas flow rate in the holding device increases, the pressure in the sealed cavity formed by the holding device and the substrate gradually decreases, effectively reducing the accumulation of the epitaxial layer on the back side of the substrate. When the inlet gas flow rate in the holding device increases to 300 sccm and the pressure in the sealed cavity formed by the holding device and the substrate is 200 Torr, the deposition phenomenon on the back side of the substrate epitaxial layer completely disappears, indicating that the holding device can effectively inhibit the deposition on the back side of the epitaxial wafer. This result shows that by reasonably controlling the gas flow rate in the holding device, the growth region of the epitaxial layer can be optimized, the controllability of the epitaxial process can be improved, and the processing and cleaning problems caused by unnecessary deposition can be reduced.

[0089] Figure 4 FIG. shows the characterization results of the rocking curve of the front side of the finished product obtained in Example 1. From Figure 4 It can be seen that after using the holding device and the corresponding process, the full width at half maximum (FWHM) of the epitaxial layer is less than 60 arcsec, indicating that the crystal quality of the epitaxial layer under this process is extremely excellent. It further shows that this process can effectively inhibit the generation of defects and provide an excellent crystal growth environment.

[0090] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A hydride vapor phase epitaxial growth system for gallium oxide epitaxial growth, characterized in that, It includes a reaction chamber; A holding device, which is located at the lower side inside the reaction chamber and is used to place a substrate; the holding device is in the shape of a groove; several support protrusions are arranged on the lower side inside the open side of the holding device, and the support protrusions are used to support the substrate; a sealed cavity is formed between the holding device and the substrate; a gas inlet is arranged on the side wall of the holding device; the gas inlet is located on the side wall between the support protrusion and the bottom of the holding device; a gas outlet is arranged at the bottom of the holding device; A nozzle, which is arranged at the upper side inside the reaction chamber and is located directly above the holding device; A gallium boat, which is placed above the nozzle; A gas passage, which is located above the gallium boat; A first annular gas path, a second annular gas path and a third annular gas path, which are arranged around the nozzle in sequence from near to far; A heating unit, which is sleeved outside the reaction chamber.

2. The hydride vapor phase epitaxial growth system for gallium oxide epitaxy according to claim 1, wherein The number of the gas inlets is 2.

3. The hydride vapor phase epitaxial growth system for gallium oxide epitaxy according to claim 1, wherein The front side of the substrate faces upward and is flush with the open side of the holding device.

4. The hydride vapor phase epitaxial growth system for gallium oxide epitaxy according to claim 1, characterized in that, It includes a rotating unit, the holding device is placed on the rotating unit, and the rotating unit realizes the rotation of the holding device.

5. A method for growing gallium oxide epitaxially using the hydride vapor phase epitaxial growth system according to any one of claims 1 to 4, characterized in that, It includes the following steps: Place the substrate on the support protrusions of the holding device; control the gas flow rates of the gas inlet and gas outlet of the holding device so that the sealed cavity formed between the holding device and the substrate is in a negative pressure; the front side of the substrate faces upward; Introduce a protective gas through the first annular gas path and the third annular gas path to purge and evacuate the air in the reaction chamber; After the reaction chamber is evacuated, use the heating unit to heat the reaction chamber to the growth temperature, then introduce hydrogen chloride through the gas passage, the hydrogen chloride contacts the gallium boat to generate gallium chloride, the hydrogen chloride is introduced into the reaction chamber through the nozzle, and oxygen is introduced through the second annular gas path to realize the epitaxial growth of gallium oxide on the substrate.

6. The method according to claim 5, wherein The gas at the gas inlet of the holding device includes nitrogen and / or argon; the negative pressure is less than or equal to 200 Torr.

7. The method according to claim 5, characterized in that The protective gas includes one or more of nitrogen, argon and helium, and the flow rate of the protective gas in the first annular gas path and the second annular gas path is 10 - 10000 sccm; The degree of vacuum for evacuation is less than or equal to 20 Pa.

8. The method according to claim 5, wherein The heating rate of temperature rise is 1 - 10 °C / min; the growth temperature is 900 - 1050 °C.

9. The method according to claim 5, wherein The flow rate of the hydrogen chloride is 20 - 200 sccm; the flow rate of the oxygen is 100 - 1000 sccm.

10. The method according to claim 5, wherein The pressure for epitaxial growth is 100 - 500 Torr.

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