Process for the oxidation of silicon carbide and its applications

Abstract

The application discloses a silicon carbide oxidation method and application thereof. The silicon carbide oxidation method comprises the following steps: contacting an oxygen source gas with a silicon carbide material at a temperature of 1000-1400 DEG C to perform a thermal oxidation reaction, so as to form an oxidation layer with a predetermined thickness on the surface of the silicon carbide material, wherein the oxygen source gas comprises oxygen, oxygen-containing gas or water vapor; and rapidly cooling the silicon carbide material to below 300 DEG C after the thermal oxidation reaction is completed. The SiC oxidation method provided by the application adopts a rapid temperature rising and falling method and a low-pressure oxidation method, solves the C contamination problem of a SiC / SiO2 interface, and thus achieves the purposes of reducing an interface state and improving the interface characteristics of the SiC / SiO2.

Description

TECHNICAL FIELD

[0001] The present application relates to a silicon carbide oxidation method, in particular to a low pressure silicon carbide oxidation method and its application, and belongs to the technical field of the third generation semiconductor. BACKGROUND

[0002] There are two main methods for fabricating the gate dielectric layer of the existing SiC MOSFET device. One is to use a multi-layer oxide layer stacking method, which uses a variety of oxides including rare earth oxides (yttria, lanthanum oxide) as a transition layer at the interface with SiC, and then deposits a SiO2 layer on top; the other way is to use thermal oxidation of SiC to directly form SiO2. Compared with the former, the thermal oxidation process is simple and direct, and does not introduce other impurities, which is more suitable for large-scale production of devices.

[0003] During the thermal oxidation of SiC, due to the presence of C, a variety of intermediate products will be produced during the chemical reaction process, mainly C, CO, SiO, and among them, solid C is an interface contamination that will affect the quality of the SiO2 layer and the SiO2 / SiC interface. It is one of the reasons for the extremely low channel mobility of SiC MOSFET. Currently, the surface mobility of thermally oxidized SiC is difficult to exceed 20 cm 2 Vs, which leads to the decline of the channel performance of SiC MOSFET and affects the overall performance of the device. SUMMARY

[0004] The main purpose of the present application is to provide a silicon carbide oxidation method and its application to overcome the shortcomings of the prior art.

[0005] To achieve the foregoing purposes of the application, the technical solutions adopted by the present application include:

[0006] The present application provides a silicon carbide oxidation method, which comprises: contacting an oxygen source gas with a silicon carbide material at a temperature of 1000-1400℃ to perform a thermal oxidation reaction, thereby forming an oxidation layer of a predetermined thickness on the surface of the silicon carbide material, wherein the oxygen source gas comprises oxygen, oxygen-containing gas or water vapor; and

[0007] After the thermal oxidation reaction is completed, the silicon carbide material is rapidly cooled to below 300℃.

[0008] The present application also provides a silicon carbide oxidation method, which comprises:

[0009] The silicon carbide thermal oxidation equipment is provided;

[0010] The silicon carbide material is placed in the reaction chamber;

[0011] The protective gas supply mechanism supplies a protective gas into the reaction chamber to remove air in the reaction chamber, and then the heating mechanism rapidly increases the temperature in the reaction chamber to 1200-1400 DEG C under the condition that the reaction chamber maintains a positive pressure relative to the environment, and then the oxygen source gas supply mechanism supplies an oxygen source gas preheated to 1200-1400 DEG C into the reaction chamber to perform the thermal oxidation reaction;

[0012] After the thermal oxidation reaction is completed, the oxygen source gas supply into the reaction chamber is stopped while the protective gas supply mechanism supplies a protective gas preheated to 1200-1400 DEG C into the reaction chamber to remove oxygen in the reaction chamber;

[0013] The heating of the reaction chamber is stopped, and the protective gas supply mechanism supplies a protective gas at room temperature into the reaction chamber to rapidly cool the silicon carbide material to below 300 DEG C.

[0014] The embodiment of the present application also provides a silicon carbide oxidation method, which comprises:

[0015] The silicon carbide thermal oxidation device is provided;

[0016] The silicon carbide material is placed into the reaction chamber;

[0017] The vacuum generation mechanism performs vacuumization on the reaction chamber to remove air in the reaction chamber;

[0018] The silicon carbide material is heated under the vacuum environment to rapidly increase the temperature to 1000-1400 DEG C, and then the oxygen source supply mechanism supplies an oxygen source gas preheated to 1000-1400 DEG C into the reaction chamber to perform the thermal oxidation reaction;

[0019] After the thermal oxidation reaction is completed, the oxygen source gas supply into the reaction chamber is stopped while the vacuum generation mechanism performs vacuumization on the reaction chamber again;

[0020] The heating of the reaction chamber is stopped, and the cooling medium supply mechanism supplies a gas as a cooling medium into the reaction chamber to rapidly cool the silicon carbide material to below 300 DEG C.

[0021] The embodiment of the present application also provides the use of the silicon carbide oxidation method in the preparation of a semiconductor device.

[0022] The embodiment of the present application also provides a semiconductor device preparation method, which comprises: forming an oxidation layer on a SiC wafer surface by using the silicon carbide oxidation method, and manufacturing a semiconductor device by using the SiC wafer as a substrate.

[0023] Compared with the prior art, the present application has the following advantages:

[0024] 1) The SiC oxidation method provided by the embodiment of the present application adopts a rapid temperature rising and falling and low pressure oxidation method, solves the C contamination problem of the SiC / SiO2 interface, reduces the interface state, and improves the interface characteristics of the SiC / SiO2.

[0025] 2) The SiC oxidation method provided by the embodiment of the present application can be used for the manufacturing of SiC devices, such as SiC high-voltage and high-power devices (SiC LDMOS, SiC VDMOS, and SiC IGBT), SiC radio frequency power amplifiers, and the like, and can also be used for the manufacturing of SiC integrated circuits. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a structure schematic diagram of a SiC MOSFET device provided in a typical embodiment of the present application;

[0027] Figure 2 is a structure schematic diagram of a SiC high-voltage and high-power LDMOS device structure provided in a typical embodiment of the present application;

[0028] Figure 3 is a structure schematic diagram of a SiC integrated circuit structure provided in a typical embodiment of the present application;

[0029] Figure 4 is a structure schematic diagram of a SiC thermal oxidation equipment adopted in the embodiment 1 of the present application;

[0030] Figure 5 is a structure schematic diagram of a SiC thermal oxidation equipment adopted in the embodiment 2 of the present application. DETAILED DESCRIPTION

[0031] In view of the solid-state C contamination problem in the SiC thermal oxidation process in the prior art, the present inventors propose a targeted technical solution. The technical solution, its implementation process and principles will be further explained as follows.

[0032] The chemical reaction process of the thermal oxidation process of SiC and oxygen mainly includes:

[0033] SiC + 3 / 2O2→ SiO2 (solid) + CO (gas)

[0034] SiC + O2→ SiO2 (solid) + C (solid)

[0035] SiC + O2→ SiO (solid) + CO (gas)

[0036] The thermal oxidation of SiC can also be realized by using gaseous water (i.e., water vapor). The thermal oxidation chemical reaction process of SiC and water vapor mainly includes:

[0037] SiC + 2H2O → SiO2(solid) + CH4(gas)

[0038] The bulk mobility of SiC is close to that of silicon, and the electron mobility is 800-1000 cm 2 Vs, and the hole mobility is 200 cm 2 Vs, in theory, the channel mobility of SiC MOSFET should also be close to the level of silicon MOSFET, solve this problem, SiC MOSFET in performance will have a considerable progress, will bring a qualitative progress to the power electronic industry and radio frequency power electronic industry.

[0039] The present inventor found that the oxidation chemical reaction of SiC at different temperatures is different, and when the oxidation temperature is relatively low, for example, at 600 DEG C, the oxidation chemical reaction formula of SiC is: SiC + O2→ SiO2(solid) + C(solid), the formation of solid carbon will contaminate the SiC / SiO2 interface and SiO2 itself, and seriously affect the interface characteristics.

[0040] When the oxidation temperature is about 1300 DEG C, the thermal oxidation reaction of silicon carbide is SiC + 3 / 2O2→ SiO2(solid) + CO(gas), at this time, there is no solid C contamination, so that high-quality SiO2 and SiC / SiO2 interface can be formed.

[0041] SiC material has the characteristics of wide band gap, high breakdown electric field, etc., and is an excellent choice for making high-voltage and high-power MOSFET devices, and the interface quality of SiC / SiO2 seriously affects the performance of SiC MOSFET devices, and is a key obstacle in device manufacturing; the oxidation method of SiC provided by the embodiment of the present application adopts the method of rapid temperature rise and fall and low pressure oxidation, solves the problem of solid C contamination of SiC / SiO2 interface, reduces the interface state, improves the interface characteristics of SiC / SiO2, and improves the performance of SiC MOSFET device.

[0042] The oxidation method of silicon carbide provided by the embodiment of the present application can reduce the interface state of the silicon carbide material or wafer, improve the interface characteristics of SiC / SiO2, and the silicon carbide wafer provided by the embodiment of the present application can be used to make MOSFET devices (such as Figure 1 As SiC is a wide band gap semiconductor material, it is very suitable for making high-voltage and high-power devices, and after improving the interface characteristics of SiC / SiO2, of course, the silicon carbide wafer provided by the embodiment of the present application can also be used to make LDMOS devices (such as Figure 2 ).

[0043] Compared with other wide band gap semiconductor materials (such as GaN), the SiC material has obvious advantages in manufacturing integrated circuits. After the SiC / SiO2 interface quality problem is solved, the SiC integrated circuit manufacturing will also be possible. Since the SiC is a wide band gap semiconductor material, it can perfectly combine high-power and low-power devices, is very suitable for making hybrid integrated circuits, and has good application prospects in the fields of manufacturing intelligent high-power systems or intelligent power systems, etc. A structure of a SiC integrated circuit provided by an embodiment of the present application is as shown in Figure 3 The left SiC MOSFET device in the figure is an input driving tube, and the right SiC LDMOS in the figure is a power output tube.

[0044] The present application aims at the problem of solid-state C contamination in the current SiC thermal oxidation process, proposes an improved oxidation process, solves the C contamination problem from the aspects of chemical reaction temperature and environment, improves the SiC / SiO2 interface quality, and thus achieves the purpose of improving the performance of the SiC device.

[0045] An embodiment of the present application provides an oxidation method of silicon carbide, which comprises: contacting an oxygen source gas with a silicon carbide material at a temperature of 1000-1400 DEG C to perform a thermal oxidation reaction, so as to form an oxidation layer with a predetermined thickness on the surface of the silicon carbide material, wherein the oxygen source gas comprises oxygen, oxygen-containing gas or water vapor; and

[0046] After the thermal oxidation reaction is completed, the silicon carbide material is rapidly cooled to below 300 DEG C.

[0047] In some more specific embodiments, the oxidation method specifically comprises:

[0048] The silicon carbide material is placed into a reaction chamber;

[0049] A protective gas is input into the reaction chamber to isolate oxygen and water vapor, and then the temperature in the reaction chamber is rapidly increased to 1200-1400 DEG C under the condition that the reaction chamber maintains a positive air pressure to the environment, and then the oxygen source gas preheated to 1200-1400 DEG C is input into the reaction chamber to perform the thermal oxidation reaction;

[0050] After the thermal oxidation reaction is completed, the oxygen source gas is stopped from being input into the reaction chamber while the protective gas preheated to 1200-1400 DEG C is input into the reaction chamber to exhaust oxygen from the reaction chamber under the condition that the temperature in the reaction chamber is unchanged;

[0051] The heating of the reaction chamber is stopped, and the protective gas at room temperature is input into the reaction chamber to rapidly cool the silicon carbide material to below 300 DEG C.

[0052] Further, the oxidation method specifically includes maintaining the pressure in the reaction chamber at 1.05 atm or more, and increasing the temperature in the reaction chamber to 1200-1400°C at a temperature increase rate of 10-50°C / s.

[0053] Further, the oxidation method specifically includes maintaining the reaction chamber in a vacuum condition, and inputting a room-temperature protective gas into the reaction chamber to rapidly cool the silicon carbide material to 300°C or less.

[0054] In some more specific embodiments, the oxidation method specifically includes:

[0055] placing the silicon carbide material in a reaction chamber;

[0056] vacuumizing the reaction chamber to remove air therefrom;

[0057] heating the silicon carbide material in a vacuum environment and rapidly increasing the temperature thereof to 1000-1400°C, and then inputting an oxygen source gas preheated to 1000-1400°C into the reaction chamber to perform the thermal oxidation reaction;

[0058] after the thermal oxidation reaction, stopping the input of the oxygen source gas into the reaction chamber while maintaining the temperature in the reaction chamber, and vacuumizing the reaction chamber again;

[0059] stopping the heating of the reaction chamber, and inputting a gas as a cooling medium into the reaction chamber to rapidly cool the silicon carbide material to 300°C or less.

[0060] Further, the gas as the cooling medium includes any one or a combination of two or more of nitric oxide, nitrous oxide, nitrogen, and an inert gas, but is not limited thereto.

[0061] Further, the gas as the cooling medium is a gas at room temperature.

[0062] Further, the oxidation method specifically includes rapidly cooling the silicon carbide material to 300°C or less in a vacuum condition.

[0063] Further, the oxidation method specifically includes increasing the temperature in the reaction chamber to 1000-1400°C at a temperature increase rate of 10-50°C / s.

[0064] Further, the protective gas includes nitrogen and / or an inert gas, but is not limited thereto.

[0065] Further, the oxidation method specifically includes rapidly cooling the temperature of the silicon carbide material to 300°C or less at a temperature decrease rate of 100-400°C / s.

[0066] The embodiment of the present application also provides a silicon carbide oxidation method, which comprises:

[0067] putting the silicon carbide material into a reaction chamber;

[0068] supplying a protective gas into the reaction chamber by a protective gas supply mechanism to isolate oxygen and water vapor, and then rapidly increasing the temperature in the reaction chamber to 1200-1400 DEG C by a heating mechanism under the condition that the reaction chamber is kept at a positive pressure relative to the environment, and then supplying an oxygen source gas preheated to 1200-1400 DEG C into the reaction chamber by an oxygen source gas supply mechanism to perform the thermal oxidation reaction;

[0069] after the thermal oxidation reaction is completed, the oxygen source gas supply into the reaction chamber is stopped while the protective gas preheated to 1200-1400 DEG C is supplied into the reaction chamber by the protective gas supply mechanism to remove oxygen in the reaction chamber;

[0070] the heating of the reaction chamber is stopped, and the protective gas at room temperature is supplied into the reaction chamber by the protective gas supply mechanism to rapidly cool the silicon carbide material to below 300 DEG C.

[0071] Further, the protective gas comprises nitrogen and / or inert gas, but is not limited thereto.

[0072] Further, the silicon carbide oxidation method specifically comprises: keeping the pressure in the reaction chamber above 1.05 atm, and increasing the temperature in the reaction chamber to 1200-1400 DEG C at a temperature increasing rate of 10-50 DEG C / s.

[0073] Further, the silicon carbide oxidation method specifically comprises: rapidly cooling the temperature of the silicon carbide material to below 300 DEG C under vacuum.

[0074] Further, the silicon carbide oxidation method specifically comprises: rapidly cooling the temperature of the silicon carbide material to below 300 DEG C at a temperature decreasing rate of 100-400 DEG C / s.

[0075] The embodiment of the present application also provides a silicon carbide oxidation method, which comprises:

[0076] putting the silicon carbide material into a reaction chamber;

[0077] vacuumizing the reaction chamber by a vacuum generating mechanism to remove air in the reaction chamber;

[0078] heating the silicon carbide material under vacuum to rapidly increase the temperature to 1000-1400 DEG C, and then supplying an oxygen source gas preheated to 1000-1400 DEG C into the reaction chamber by an oxygen source supply mechanism to perform the thermal oxidation reaction;

[0079] After the thermal oxidation reaction is completed, the input of the oxygen source gas into the reaction chamber is stopped while the temperature in the reaction chamber is maintained, and the reaction chamber is vacuumed again by a vacuum generating mechanism;

[0080] The heating of the reaction chamber is stopped, and a gas as a cooling medium is input into the reaction chamber by a cooling medium supplying mechanism to rapidly cool the silicon carbide material to below 300℃.

[0081] Further, the gas as the cooling medium is a room temperature gas.

[0082] Further, the gas as the cooling medium includes any one or a combination of two or more of nitric oxide, nitrogen and inert gas, but is not limited thereto.

[0083] Further, the protective gas includes nitrogen and / or inert gas, but is not limited thereto.

[0084] Further, the oxidation method specifically includes increasing the temperature in the reaction chamber to 1000-1400℃ at a temperature increasing rate of 10-50℃ / s.

[0085] Further, the oxidation method specifically includes rapidly cooling the silicon carbide material to below 300℃ under vacuum.

[0086] Further, the oxidation method specifically includes rapidly cooling the temperature of the silicon carbide material to below 300℃ at a temperature decreasing rate of 100-400℃ / s.

[0087] The embodiment of the present application also provides the use of the oxidation method of the silicon carbide in the preparation of a semiconductor device.

[0088] The embodiment of the present application also provides a semiconductor device preparation method, which includes forming an oxide layer on the surface of a SiC wafer by the oxidation method of the silicon carbide, and using the SiC wafer as a substrate to manufacture a semiconductor device.

[0089] The technical solution, its implementation process and principles will be further explained in combination with the accompanying drawings and specific implementation cases.

[0090] Embodiment 1

[0091] An oxidation method of silicon carbide, specifically including:

[0092] 1) providing a silicon carbide material as described above, Figure 4The thermal oxidation equipment shown in the figure, wherein 1 is an oxidation furnace tube, which has an oxidation cavity, i.e. the reaction chamber, inside. The material of the oxidation furnace tube can be quartz or silicon carbide. The oxidation furnace tube can be heated by a heating mechanism such as a resistance wire heating mechanism. The SiC substrate can be placed on a quartz boat, which can be sent into the oxidation cavity through the opening on the right side of the oxidation cavity by a guide rail. 2 is a protective gas inlet. The protective gas can be an inert gas such as argon or nitrogen. 3 is an oxygen source gas inlet. The oxygen source gas can be oxygen, oxygen-containing gas, or water vapor.

[0093] 2) The SiC substrate is sent into the oxidation cavity inside the oxidation furnace tube 1 from the right side opening. Nitrogen or argon is introduced into the oxidation furnace tube 1 from the protective gas inlet 2 on the left side of the oxidation furnace tube 1 at a flow rate of 1L / min-10L / min to isolate oxygen and water vapor. The nitrogen or argon introduced can be heated to 1200-1400℃.

[0094] 3) The pressure inside the oxidation furnace tube is maintained at 1.05atm or above. The oxidation furnace tube is rapidly heated to 1200-1400℃ at a heating rate of 10℃ / s-50℃ / s. Then the oxygen source gas inlet 3 is opened, and the preheated oxygen source gas at 1200-1400℃ is introduced into the oxidation furnace tube 1 at a flow rate of 1L / min-10L / min according to the oxidation rate requirement to perform thermal oxidation on the SiC substrate, so as to form a predetermined thickness of silicon oxide layer on the surface of the SiC substrate.

[0095] 4) After the oxidation is completed, the oxygen source gas inlet 3 is closed while the protective gas inlet 2 is opened. The preheated nitrogen or argon at 1200-1400℃ is introduced into the oxidation furnace tube at a flow rate of 1L / min-10L / min for 30 minutes to 1 hour to perform oxygen removal on the oxidation furnace tube.

[0096] 5) The heating system is turned off. The room temperature nitrogen or argon is introduced into the oxidation furnace tube at a flow rate of 5L / min-30L / min to rapidly cool the oxidized SiC substrate. The temperature of the SiC substrate can be rapidly reduced to below 300℃ at a cooling rate of 100-400℃ / s. The thermal oxidation process of SiC is completed.

[0097] Example 2

[0098] A method for oxidizing silicon carbide, specifically comprising:

[0099] 1) providing a thermal oxidation equipment as shown in the figure, Figure 5The low-pressure oxidation equipment is shown, wherein 21 is an oxidation cavity, which can be made of stainless steel; 22 is a protective gas input port; 23 is an oxygen source gas input port, which can be oxygen, water vapor, etc.; 24 is a vacuum pump connection port; 25 is an exhaust port; 26 is a substrate inlet, which is shown as being arranged on the top cover of the oxidation cavity. Of course, a side door can also be arranged on the side of the oxidation cavity, and the substrate is fed into the oxidation cavity through the side door.

[0100] 2) The SiC substrate is fed into the oxidation cavity 21 through the top cover or the side door, and the pressure in the oxidation cavity is adjusted to 0.1 mTorr-0.001 mTorr by the vacuum pump. The SiC substrate is heated to 1000-1400℃ in the vacuum state, and then the oxygen source gas is introduced into the oxidation cavity 21 at a flow rate of 1 L / min-10 L / min to perform a thermal oxidation reaction (the oxygen source gas can be oxygen, oxygen-containing gas or water vapor, etc.), and the growth pressure is 10 mTorr-1000 mTorr, so as to oxidize the surface layer of the SiC substrate to form a silicon oxide layer with a predetermined thickness.

[0101] 3) After the oxidation is completed, the temperature of the SiC substrate is maintained at 1000-1400℃, and the oxidation cavity is again vacuumed to 0.1 mTorr-0.001 mTorr. The cooling mode of the SiC substrate can be two kinds:

[0102] One is to directly cool the SiC substrate to below 300℃ in a high-vacuum environment, so as to ensure that there is no oxidation reaction during the cooling process, and the SiC / SiO2 interface is clean and will not be contaminated by C.

[0103] The other is to introduce nitrogen monoxide, dinitrogen monoxide, nitrogen or argon as a cooling medium into the oxidation cavity 21 at a flow rate of 5 L / min-30 L / min, and the SiC substrate is rapidly cooled to below 300℃ in the nitrogen monoxide, dinitrogen monoxide, nitrogen or argon atmosphere, and the SiC low-pressure oxidation process is completed.

[0104] The rapid cooling under the protective gas can avoid the oxidation of SiC at low temperature, so as to avoid the generation of C contamination at the SiC / SiO2 interface. The low-pressure oxidation method has at least the following three advantages: first, the adsorption / aggregation of CO or CH4 at the SiC / SiO2 interface is low under low pressure, the SiC interface is fully exposed, the oxidation process is more complete, and the generation of interface C contamination is avoided; second, the solid solubility of CO / CH4 in SiO2 is low under low pressure, so low pressure is beneficial to the rapid removal of CO / CH4 from the SiC / SiO2 interface, thereby avoiding the interface C contamination; third, the temperature rising and falling process in the vacuum environment avoids the oxidation of SiC at low temperature, and reduces the occurrence of C contamination.

[0105] The embodiment of the present application carries out thermal oxidation of SiC substrate in vacuum environment, and avoids contact between SiC and oxygen source gas at low temperature, thereby cutting off the chance of oxidation of SiC at low temperature, avoiding C contamination of SiC / SiO2 interface, and improving the quality of SiC / SiO2 interface.

[0106] The embodiment of the present application provides a method for oxidizing SiC, solves the problem of C contamination of SiC / SiO2 interface, reduces interface state, and is beneficial to improving the performance of SiC MOSFET device; the method for oxidizing SiC can be used for manufacturing SiC device, such as SiC high-voltage high-power device (SiC LDMOS, SiC VDMOS and SiC IGBT), SiC radio frequency power amplifier, and the like, and can also be used for realizing manufacturing of SiC integrated circuit.

[0107] It should be understood that the above embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A method of oxidizing silicon carbide, characterized by The method comprises: placing a silicon carbide material in a reaction chamber; supplying a protective gas into the reaction chamber to isolate oxygen and water vapor, maintaining the pressure in the reaction chamber at 1.05 atm or more, raising the temperature in the reaction chamber to 1200-1400 °C at a temperature raising rate of 10-50 °C / s, then supplying an oxygen source gas preheated to 1200-1400 °C into the reaction chamber, and making the oxygen source gas contact with the silicon carbide material to perform a thermal oxidation reaction, thereby forming an oxidation layer of a predetermined thickness on the surface of the silicon carbide material; after the thermal oxidation reaction, stopping the supply of the oxygen source gas into the reaction chamber while maintaining the temperature in the reaction chamber, and supplying a protective gas preheated to 1200-1400 °C into the reaction chamber to perform oxygen removal of the reaction chamber; stopping heating of the reaction chamber, and supplying a protective gas at room temperature into the reaction chamber to lower the temperature of the silicon carbide material to 300 °C or less at a temperature lowering rate of 100-400 °C / s; or, performing vacuumization of the reaction chamber to isolate oxygen and water vapor; raising the temperature in the reaction chamber to 1000-1400 °C at a temperature raising rate of 10-50 °C / s, heating the silicon carbide material in a vacuum environment and rapidly raising the temperature of the silicon carbide material to 1000-1400 °C, then supplying an oxygen source gas preheated to 1000-1400 °C into the reaction chamber, and making the oxygen source gas contact with the silicon carbide material to perform a thermal oxidation reaction, thereby forming an oxidation layer of a predetermined thickness on the surface of the silicon carbide material; after the thermal oxidation reaction, stopping the supply of the oxygen source gas into the reaction chamber while maintaining the temperature in the reaction chamber, and performing vacuumization of the reaction chamber again; stopping heating of the reaction chamber, and supplying a gas as a cooling medium into the reaction chamber to lower the temperature of the silicon carbide material to 300 °C or less at a temperature lowering rate of 100-400 °C / s; wherein the oxygen source gas comprises oxygen, an oxygen-containing gas, or water vapor.

2. The oxidation method of claim 1, wherein: The gas as the cooling medium comprises any one or a combination of two or more of nitric oxide, nitrous oxide, nitrogen, and an inert gas.

3. The oxidation method according to claim 1 or 2, characterized in that: The gas as the cooling medium is a gas at room temperature.

4. The oxidation method of claim 1, wherein: The oxidation method specifically comprises rapidly lowering the temperature of the silicon carbide material to 300 °C or less under vacuum.

5. The oxidation method of claim 1, wherein: The protective gas comprises nitrogen and / or an inert gas.

6. A method of oxidizing silicon carbide, characterized by The method comprises: placing a silicon carbide material in a reaction chamber; supplying a protective gas into the reaction chamber to isolate oxygen and water vapor by a protective gas supply mechanism, maintaining the pressure in the reaction chamber at 1.05 atm or more, raising the temperature in the reaction chamber to 1200-1400 °C at a temperature raising rate of 10-50 °C / s by a heating mechanism, then supplying an oxygen source gas preheated to 1200-1400 °C into the reaction chamber by an oxygen source gas supply mechanism to perform a thermal oxidation reaction, thereby forming an oxidation layer of a predetermined thickness on the surface of the silicon carbide material; after the thermal oxidation reaction, stopping the supply of the oxygen source gas into the reaction chamber while maintaining the temperature in the reaction chamber, and supplying a protective gas preheated to 1200-1400 °C into the reaction chamber by the protective gas supply mechanism to perform oxygen removal of the reaction chamber; The heating of the reaction chamber is stopped, and a room temperature protective gas is supplied to the reaction chamber by a protective gas supply mechanism, and the silicon carbide material is rapidly cooled to 300°C or less at a cooling rate of 100-400°C / s.

7. The method of oxidizing silicon carbide according to claim 6, wherein: The protective gas includes nitrogen and / or an inert gas.

8. A method of oxidizing silicon carbide, characterized by The method for oxidizing silicon carbide comprises: placing a silicon carbide material in a reaction chamber; vacuumizing the reaction chamber by a vacuum generating mechanism to isolate oxygen and water vapor; raising the temperature in the reaction chamber to 1000-1400°C at a temperature raising rate of 10-50°C / s, rapidly heating the silicon carbide material to 1000-1400°C in a vacuum environment, and then supplying an oxygen source gas preheated to 1000-1400°C to the reaction chamber by an oxygen source supply mechanism to perform a thermal oxidation reaction, thereby forming an oxidation layer of a predetermined thickness on the surface of the silicon carbide material; after the thermal oxidation reaction is completed, the temperature in the reaction chamber is maintained, and the supply of the oxygen source gas to the reaction chamber is stopped, and the reaction chamber is vacuumized again by the vacuum generating mechanism; the heating of the reaction chamber is stopped, and a gas as a cooling medium is supplied to the reaction chamber by a cooling medium supply mechanism to cool the silicon carbide material to 300°C or less at a cooling rate of 100-400°C / s.

9. The method of oxidizing silicon carbide according to claim 8, wherein: The gas as the cooling medium is a room temperature gas.

10. The method of oxidizing silicon carbide of claim 8, wherein: The gas as the cooling medium includes any one or a combination of two or more of nitric oxide, nitrous oxide, nitrogen, and an inert gas.

11. The method of oxidizing silicon carbide according to claim 8, wherein The method for oxidizing silicon carbide specifically comprises rapidly cooling the silicon carbide material to 300°C or less in a vacuum.

12. Use of the method for oxidizing silicon carbide according to any one of claims 1-11 in the production of a semiconductor device.

13. A method of fabricating a semiconductor device, characterized by The method for oxidizing silicon carbide according to any one of claims 1-11 is used to form an oxidation layer on the surface of a SiC wafer, and a semiconductor device is produced using the SiC wafer as a substrate. The method for oxidizing silicon carbide according to any one of claims 1-11 is used to form an oxidation layer on the surface of a SiC wafer, and a semiconductor device is produced using the SiC wafer as a substrate.

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