A gas inlet device for a silicon carbide chemical vapor deposition furnace and a method of using the same

Abstract

The application relates to the technical field of silicon carbide vapor deposition equipment, and particularly discloses a gas inlet device of a silicon carbide chemical vapor deposition furnace and a use method thereof. The gas inlet device comprises an MTS liquid storage tank, a liquid flow control device, a preheating device, a low-pressure gasification chamber and a low-pressure uniform gas tank which are sequentially arranged, the low-pressure gasification chamber is connected with the low-pressure uniform gas tank through a vacuum pump, and the low-pressure uniform gas tank is connected with a reaction chamber through the vacuum pump; MTS is sequentially led into the reaction chamber through the preheating device, the low-pressure gasification chamber and the low-pressure uniform gas tank from the MTS liquid storage tank. The application realizes flexible and controllable real-time reaction gas volume, cooperates with carrier gas inlet volume, achieves the purpose of proportionally adjustable and stable, can realize stable operation for a long time, and breaks the limitation of operation time length by the maximum storage capacity of MTS.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of silicon carbide vapor deposition equipment, and more particularly to an air inlet device of a silicon carbide chemical vapor deposition furnace and a use method thereof. BACKGROUND

[0002] Chemical vapor deposition (CVD) is an important process for producing high-purity silicon carbide solid materials. The ceramic precursor reactant commonly used in the industry for chemical vapor deposition of silicon carbide is liquid, represented by methyltrichlorosilane (MTS), and the reaction equation is as follows: CH3SiCl3→SiC+3HCl. Since it is liquid at room temperature, and CVD has a process requirement that the reactant must be in gas phase. Therefore, it is necessary to convert it into gas phase and realize the controllability of its reaction amount through some process during preparation.

[0003] At present, there are three controllable ways to supply MTS vapor into the deposition chamber:

[0004] Method one: bubble type vapor transportation method, which is to pass carrier gas (hydrogen) into MTS liquid to use the bubbles generated by the carrier gas in the MTS liquid to carry the vapor into the deposition chamber. The specific heat capacity of the carrier gas is large, and the precursor is not easy to liquefy during the transportation of the precursor. However, the disadvantages of this method are as follows:

[0005] 1. The mixed vapor produced by this method contains two components, carrier gas and MTS, and the ratio of the two needs to be determined according to the temperature and pressure of the bubbling chamber. The shape of the bubbling chamber will also affect the ratio, and the amount of carrier gas introduced each time varies greatly in actual use.

[0006] 2. As the MTS is consumed, the space in the bubbling chamber will change, and the vaporization rate of MTS will also change, resulting in a change in the amount of MTS carried out by the carrier gas. It is difficult to accurately control the ratio of carrier gas and precursor in practice, so it is difficult to output MTS smoothly for a long time in practice.

[0007] 3. The MTS storage device is a closed structure, and it is not possible to add MTS during the execution of a long-time deposition operation. The deposition operation time is limited, and for a large-capacity closed MTS storage device that extends the operation time, the MTS cannot be uniformly heated when evaporated.

[0008] 4. The combination of the mixing tank and the buffer tank used in this method can obviously reduce pressure fluctuations, but the structure is complex and the volume is large.

[0009] Method two: heating type vapor delivery method, is to heat a large amount of MTS gasification in the evaporation chamber, a large amount of MTS vapor is generated, and the resulting vapor is supplied to the deposition chamber. The gas flow is controlled by MFC (mass flow meter, used for accurate control of gas flow). This method can produce a large amount of MTS vapor in unit time, and it is also convenient to adjust the ratio of MTS to hydrogen. But the shortcomings of this method are as follows:

[0010] 1. This method uses MFC as the flow controller of MTS gas, which needs a large pressure difference to effectively control the flow (traditional MFC needs 15 psi pressure to open), and it is difficult to reach a large pressure difference for MTS gas evaporation, and too large MTS pressure is not conducive to MTS evaporation, so the vapor is easy to liquefy and block the pipeline during transportation.

[0011] 2. This method needs to apply higher temperature to the evaporation chamber when reaching the above-mentioned high pressure difference, and high temperature is easy to denature MTS, thereby losing the working function.

[0012] 3. The combination of mixing chamber and dilution chamber used in this method can obviously reduce pressure fluctuation and make the carrier gas reaction gas mixture more uniform, but the structure is complex and the volume is large.

[0013] Method three: MTS flow control method, is to supply MTS in liquid form to the evaporation chamber, and control the flow by LMFC (liquid mass flow controller, used for precise control of liquid flow). In the use of MTS, the evaporation chamber evaporates MTS to obtain vapor and supplies it to the deposition chamber. This method can accurately control the flow of MTS. But the shortcomings of this method are as follows:

[0014] 1. The evaporation amount of liquid MTS in this method is limited, resulting in limited input amount.

[0015] 2. This method does not consider the actual problem of MTS vapor heat absorption and cooling in the evaporation chamber, and does not involve corresponding heat preservation and heating measures.

[0016] 3. The MTS vapor generated in the evaporation chamber of this method is easy to vaporize to form small droplets, and the amount of MTS gas supplied to the deposition chamber is less than the amount of MTS liquid supplied, which greatly affects the deposition effect.

[0017] In addition, the above-mentioned several methods are also easy to produce aerosol (suspended small droplets) in practice, which will bring impurities in MTS into the deposition chamber, affecting the purity of silicon carbide products. SUMMARY

[0018] The present application provides a gas inlet device of a silicon carbide chemical vapor deposition furnace and a use method thereof.

[0019] Different from the previous method of gasifying MTS by heating, bubbling, etc., the application designs a low-pressure gasification chamber, greatly reduces the boiling point of MTS by reducing the gas pressure, so that MTS can be rapidly and completely gasified in the low-pressure gasification chamber. By controlling the input amount of liquid MTS, the amount of reactant gas is flexibly and controllably realized in real time, and the amount of carrier gas is inputted to achieve the purpose of proportionally adjustable and stable. The main gas path is designed at low pressure, and no MTS droplets are generated during the transportation of MTS gas at room temperature. The application breaks through the limitation of the maximum storage amount of MTS on the operation time.

[0020] In a first aspect, the application provides a gas inlet device of a silicon carbide chemical vapor deposition furnace, which adopts the following technical scheme:

[0021] A gas inlet device of a silicon carbide chemical vapor deposition furnace, the gas inlet device comprises an MTS liquid storage tank, a liquid flow control device, a preheating device, a low-pressure gasification chamber, and a low-pressure uniform gas tank arranged in sequence, the low-pressure gasification chamber is connected with the low-pressure uniform gas tank through a vacuum pump, and the low-pressure uniform gas tank is connected with a reaction chamber through a vacuum pump; MTS enters the reaction chamber from the MTS liquid storage tank through the preheating device, the low-pressure gasification chamber, and the low-pressure uniform gas tank in sequence.

[0022] Optionally, the low-pressure gasification chamber is provided with a temperature compensation device.

[0023] In the application, the temperature compensation device is arranged in the low-pressure gasification chamber to compensate for the large amount of heat loss of liquid gasification, and at the same time, the MTS gasification speed is faster and the gasification is more complete.

[0024] Optionally, the temperature compensation device is a rotating gasification disc with temperature compensation and heating functions.

[0025] Optionally, the diameter of the rotating gasification disc is 5-50 cm, and the rotating speed is 50-5000 rpm.

[0026] The diameter of the rotating gasification disc is positively correlated with the maximum gasification rate of the rotating gasification disc. In the application, the parameters of the rotating gasification disc, i.e., the diameter of 5-50 cm and the rotating speed of 50-5000 rpm, can ensure the high-speed gasification requirement of MTS.

[0027] Optionally, the rotating gasification disc comprises a bottom dripping platform, an inverted slope middle part, and an inverted hook type edge connected in sequence from the bottom to the edge.

[0028] The rotating gasification disc of the application can effectively realize the effect of liquid dispersion under low pressure and high-speed boiling gasification, and has the effect of preventing splashing, which can ensure the long-term stable operation of the overall equipment. At the same time, the rotating gasification disc has heating and temperature compensation functions, which are used to compensate for the large amount of heat absorbed during liquid gasification and ensure the constant temperature of the low-pressure gasification chamber under long-term operation.

[0029] Optionally, the low-pressure gasification chamber is further provided with baffles arranged staggered below the rotating gasification disc.

[0030] In the application, by arranging baffles in the low-pressure gasification chamber, the low-pressure transportation path of MTS is increased, and the gasification effect of MTS is increased, thereby greatly reducing the small droplets generated in the MTS gas.

[0031] Optionally, the low-pressure uniform gas tank is provided with an injection port of carrier gas and a carrier gas control device.

[0032] In the application, the carrier gas control device is used to accurately control the gas flow of the carrier gas, so as to better control the ratio of the carrier gas and the MTS reaction gas.

[0033] Optionally, the low-pressure uniform gas tank is provided with baffles arranged staggered.

[0034] In the second aspect, the application provides a use method of the gas inlet device of the silicon carbide chemical vapor deposition furnace, which adopts the following technical scheme:

[0035] A use method of the gas inlet device of the silicon carbide chemical vapor deposition furnace, opens the control switch in the device, and the MTS in the MTS storage tank sequentially passes through the preheating device and the low-pressure gasification chamber, is gasified, and then enters the low-pressure uniform gas tank, is uniformly mixed with the carrier gas injected into the low-pressure uniform gas tank, and the mixed gas is output from the low-pressure uniform gas tank and input into the reaction chamber for deposition operation; the liquid MTS is rapidly gasified in the low-pressure gasification chamber, and the input amount of MTS is controlled in real time by the liquid flow control device.

[0036] Optionally, the flow control of the liquid flow control device is 1-10 ml / min.

[0037] Optionally, the preheating temperature of the preheating device is 30-60℃.

[0038] Optionally, the actual heating temperature of the heat compensation device in the low-pressure gasification chamber is 30-80℃.

[0039] Optionally, the pressure of the low-pressure gasification chamber and the low-pressure uniform gas tank is controlled at 500-3000 Pa.

[0040] Optionally, the pressure of the low-pressure vaporization chamber (6) is controlled at 500-3000 Pa, and the pressure of the low-pressure gas equalization tank (11) is 0.5-50 kPa higher than the pressure of the low-pressure vaporization chamber (6).

[0041] Optionally, the pressure in the reaction chamber is controlled at 1000-2000 Pa.

[0042] When using the silicon carbide chemical vapor deposition furnace of this application for silicon carbide deposition, in order to control the amount of small droplets in gaseous MTS and the MTS vaporization rate to the optimal level, this application controls the above parameters within the above range.

[0043] In summary, this application has the following beneficial effects:

[0044] 1. In this application, the low-pressure vaporization chamber design greatly reduces the boiling point of MTS, thereby greatly increasing the vaporization rate of MTS and greatly reducing the vaporization temperature under high vaporization rate. The generated MTS gas is at room temperature and is transported under low pressure, avoiding large-scale pipeline insulation facilities. At the same time, it avoids the generation of small droplets during MTS transportation, which would affect the deposition effect and MTS transportation efficiency.

[0045] 2. The device in this application can vaporize the input MTS liquid at high speed. The amount of gas can be controlled in real time by directly controlling the amount of MTS liquid entering the device. It also achieves long-term process stability and adjustable ratio of MTS liquid with hydrogen and argon carrier gas.

[0046] 3. This application adopts an external liquid phase supply method for MTS, which breaks through the limitation of deposition operation time in conventional closed systems by the maximum storage capacity of MTS. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the air intake device of this application.

[0048] Figure 2 This is a detailed schematic diagram of the air intake device of this application.

[0049] Figure 3 This is a three-dimensional structural diagram of the rotating vaporization disc.

[0050] Figure 4 for Figure 3 Three-dimensional cross-sectional view of the rotating vaporization disc.

[0051] Figure 5 This is a top view of the rotating vaporization disc.

[0052] Figure 6 for Figure 5 A cross-sectional view of the rotating vaporization disc along the location of AA.

[0053] Reference: 1. MTS storage tank; 2. Control valve; 3. Liquid flow control device; 4. Preheating device; 5. Rotating gasification disc; 6. Low-pressure gasification chamber; 7. Baffle; 8. Valve one; 9. Vacuum pump one; 10. Valve two; 11. Low-pressure uniform gas tank; 12. Valve three; 13. Vacuum pump two; 14. Valve four; 15. Reaction chamber; 16. Air pressure detector one; 17. Carrier gas control device; 18. Air pressure detector two. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below with reference to the drawings. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0055] The present application will be further described in detail below in combination with examples, comparative examples and performance test results.

[0056] EMBODIMENT

[0057] EMBODIMENT 1

[0058] The present embodiment provides an air inlet device of a silicon carbide chemical vapor deposition furnace.

[0059] In combination with Figure 1 and Figure 2 , the air inlet device comprises MTS storage tank 1, liquid flow control device 3, preheating device 4, low-pressure gasification chamber 6 and low-pressure uniform gas tank 11 arranged in sequence, the low-pressure gasification chamber 6 is connected with the low-pressure uniform gas tank 11 through a vacuum pump, and the low-pressure uniform gas tank 11 is connected with the reaction chamber 15 through a vacuum pump. The MTS enters the reaction chamber 15 from the MTS storage tank 1 in sequence through the preheating device 4, the low-pressure gasification chamber 6 and the low-pressure uniform gas tank 11. In addition, in order to supplement the large amount of heat absorbed by the liquid MTS after low-pressure boiling gasification, a heat supplement device can be arranged in the low-pressure gasification chamber 6, so as to maintain the temperature in the chamber and make the MTS gasification more complete. Further, the whole device operates under an inert atmosphere, which is convenient for supplementing MTS to the MTS storage tank 1 and avoids the risk of micro-leakage in the negative pressure system.

[0060] Reference Figure 2, the MTS storage tank 1 is connected with the low-pressure gasification chamber 6 in sequence with a control valve 2, a liquid flow control device 3, and a preheating device 4, the low-pressure gasification chamber 6 is connected with a vacuum pump one 9 at an end away from the preheating device 4, and the low-pressure gasification chamber 6 is in a low-pressure state under the continuous vacuum pumping of the vacuum pump one 9. In a working state, the control valve 2 is opened, the value of the liquid flow control device 3 is adjusted, and the MTS in the MTS storage tank 1 is input into the low-pressure gasification chamber 6 through the preheating device 4. The liquid flow control device 3 is a peristaltic pump or an LMFC device. The preheating temperature of the preheating device is 30-60°C.

[0061] With reference to Figure 2 The low-pressure gasification chamber 6 is provided with a rotating gasification disc 5 and baffles 7 arranged in an interleaved manner below the rotating gasification disc 5. The rotating gasification disc 5 has a temperature compensation heating function, which is used to compensate for a large amount of heat absorbed by the liquid MTS after low-pressure boiling gasification, so as to maintain the internal temperature of the low-pressure gasification chamber 6. The baffles 7 are used to increase the transportation path of the MTS and enhance the gasification effect of the MTS, so as to greatly reduce the small droplets generated in the MTS gas. The low-pressure gasification chamber 6 is further provided with a gas pressure detector one 16 for detecting the gas pressure in the low-pressure gasification chamber 6. In a working state, the MTS enters the low-pressure gasification chamber 6 through a pipeline, drops to the center of the rotating gasification disc 5, and is quickly coated and spread by the rotating gasification disc 5. Due to the low-pressure environment formed by the continuous vacuum pumping of the vacuum pump one 9, the MTS droplets after coating and spreading are quickly boiled and gasified, and are then pumped out by the vacuum pump 9 through the interleaved baffles 7. Further, the surface temperature of the rotating gasification disc 5 is 50-80°C. Further, the preheating device can be combined with the function of the rotating gasification disc.

[0062] With reference to Figure 2, low-pressure gasification chamber 6 and reaction chamber 15 are sequentially connected with vacuum pump one 9, low-pressure uniform gas tank 11, vacuum pump two 13. The low-pressure uniform gas tank 11 is further provided with injection of hydrogen, argon and other carrier gas, and is provided with carrier gas control device 17. The carrier gas flow is controlled. The two ends of the vacuum pump one 9 are respectively provided with valve one 8 and valve two 10, and the two ends of the vacuum pump two are respectively provided with valve three 12 and valve four 14. The low-pressure uniform gas tank 11 is further provided with gas pressure detector two 18 for detecting the gas pressure in the low-pressure uniform gas tank 11. In the working state, the MTS gas is continuously extracted from the low-pressure gasification chamber 6 through the vacuum pump one 9 and injected into the low-pressure uniform gas tank 11, and the hydrogen, argon and other carrier gas are injected at the same time, and the flow of each part is controlled through the carrier gas control device 17, and each part of the gas is uniformly mixed in the low-pressure uniform gas tank 11. After the mixed gas is output from the low-pressure uniform gas tank 11, it is input into the reaction chamber 15 through the vacuum pump two 13 and performs deposition work. Further, the low-pressure uniform gas tank 11 is provided with staggered baffles inside. The carrier gas control device 17 can select MFC, float flow meter and other gas flow control devices.

[0063] Figure 3 and Figure 4 As shown in the schematic diagram of the three-dimensional structure of the rotating gasification disc 5. Combined with Figure 5 and Figure 6 , the specific structure of the rotating gasification disc 5 is as follows:

[0064] The rotating gasification disc 5 is designed as a thin-walled disc as a whole and is used in the low-pressure gasification chamber 6. It includes three parts: bottom drop platform, inverted slope middle part and inverted hook type edge connected in sequence from the bottom to the edge.

[0065] ① is the bottom drop platform design, which is the main receiving position of the MTS liquid drop. With the rapid rotation of the rotating gasification disc 5, the MTS liquid drop is quickly spread, the MTS liquid starts to boil, gasify and uniformly disperse to ②.

[0066] ② is a small-angle inverted slope design, which is the main boiling and gasification position. With the rapid rotation of the rotating gasification disc 5, the specific surface area of the MTS liquid at ② rapidly increases under the action of centrifugal force, and sharply boils and gasifies. This position is connected to ③.

[0067] ③ is an anti-splashing inverted hook design. In actual use, due to factors such as vibration, shaking and airflow, a small number of MTS liquid that has not been gasified is easy to be thrown out of the rotating gasification disc 5 under the action of centrifugal force and splash into the low-pressure gasification chamber 6, which can easily lead to pollution over a long period of time. This place can use the centrifugal inertia of the MTS liquid drop to guide the liquid drop that has not been completely gasified back to ① to repeat the above gasification journey.

[0068] As described above, the rotating gasification disc 5 can effectively realize the effect of liquid dispersion at low pressure, high-speed boiling gasification, and has the effect of preventing splashing, which can ensure the long-term stable operation of the overall equipment. At the same time, the rotating gasification disc 5 has a low-temperature heating function, which is used to supplement the large amount of heat absorbed during liquid gasification, and ensure the temperature of the low-pressure gasification chamber 6 constant under long-term work.

[0069] Example 2

[0070] The present embodiment provides a method for using the gas inlet device of the silicon carbide chemical vapor deposition furnace of Example 1. In the present embodiment, the liquid flow control device 3 is a peristaltic pump. The specific method is as follows:

[0071] 1. First, open the control valve 2, adjust the peristaltic pump value to 1-10 ml / min, set the preheating device 4 temperature to 40-60℃, input the MTS in the MTS storage tank 1 into the low-pressure gasification chamber 6, and drop it to the center of the rotating gasification disc 5. The diameter of the rotating gasification disc 5 used is 5-50 cm, the rotating speed of the rotating gasification disc 5 is adjusted to 50-5000 rpm, and the surface temperature is 50-80℃.

[0072] 2. Then, open valve one 8 and valve two 10, adjust the opening of vacuum pump one 9, and connect the signal of air pressure detector one 16, feedback and maintain the pressure of low-pressure gasification chamber 6 to 500-3000 Pa. During the process, the liquid MTS after coating and spreading is rapidly boiled and gasified, and the MTS gas is extracted by vacuum pump one 9 after passing through the staggered baffles 7 in the low-pressure gasification chamber 6. Among them, the diameter of the rotating gasification disc 5 is positively correlated with the maximum gasification rate of the rotating gasification disc 5.

[0073] 3. Open valve three 12 and valve four 14, MTS gas is continuously extracted from the low-pressure gasification chamber 6 by vacuum pump one 9 and injected into the low-pressure uniform gas tank 11, while the fixed flow of hydrogen, argon and other carrier gas controlled by the carrier gas control device 17 is injected, and the gas is uniformly mixed in the low-pressure uniform gas tank 11. Adjust the opening of vacuum pump two 13 and connect air pressure detector two 18 to maintain the pressure of low-pressure uniform gas tank 11 to 500-3000 Pa.

[0074] 4. After the mixed gas is output from the low-pressure uniform gas tank 11, it is input into the reaction chamber 15 by vacuum pump two 13 for deposition operation;

[0075] 5. After filtering test, the small droplet content in the gaseous MTS of the present embodiment is 0-0.2wt.%, and the MTS gasification rate is 99.8%-100%.

[0076] The specific analysis is as follows:

[0077] (1) Test method of liquid droplet content in gaseous MTS:

[0078] The reaction chamber 15 is replaced with a liquid droplet filtration device under negative pressure filled with silica particles. The weight change of the device before and after filtration is tested to obtain the weight of the filtered liquid droplets, and the weight percentage of the liquid droplets in gaseous MTS is calculated based on the total weight of MTS.

[0079] (2) MTS gasification rate calculation method:

[0080] MTS gasification rate = (MTS total weight - liquid droplet inventory) / MTS total weight x 100%

[0081] (3) Reaction gas temperature measurement method:

[0082] The reaction chamber 15 is replaced with a gas temperature sensing device to monitor the temperature of the exhaust gas, and the reading is taken after the temperature is stable for 30 seconds.

[0083] The small liquid droplet inventory in gaseous MTS of the gas inlet device of the silicon carbide chemical vapor deposition furnace of the present application is detected under different parameters, and the MTS gasification rate is calculated and compared with the data of the three methods described in the background art. The results are shown in Table 1.

[0084] Table 1 Detection results of small liquid droplet inventory in gaseous MTS, MTS gasification rate, and reaction gas temperature

[0085]

[0086]

[0087] As can be seen from Table 1, when using the gas inlet device of the present application, the reaction gas is at room temperature, and the low pressure greatly reduces the boiling point of MTS, which is much lower than the conventional room temperature, which can effectively reduce the small liquid droplet inventory in gaseous MTS, while ensuring the MTS gasification rate, the small liquid droplet inventory in gaseous MTS is 0-0.2 wt.%, the MTS gasification rate is 99.8%-100%, and the large-scale heat preservation transmission redundancy is avoided, saving energy.

[0088] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing examples, or make equivalent substitutions for part of the technical features; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A gas inlet device for a silicon carbide chemical vapor deposition furnace, characterized by, The air inlet device comprises an MTS storage tank (1), a liquid flow control device (3), a preheating device (4), a low-pressure gasification chamber (6), and a low-pressure uniform gas tank (11) arranged in sequence, the low-pressure gasification chamber (6) is connected with the low-pressure uniform gas tank (11) through a vacuum pump, and the low-pressure uniform gas tank (11) is connected with a reaction chamber (15) through a vacuum pump; MTS is sequentially introduced into the reaction chamber (15) from the MTS storage tank (1) through the preheating device (4), the low-pressure gasification chamber (6), and the low-pressure uniform gas tank (11). The low-pressure gasification chamber (6) is provided with a rotating gasification disc (5) having a temperature compensation and heating function; the rotating gasification disc (5) comprises a bottom dripping platform, an inverted slope middle part, and an inverted hook-shaped edge connected in sequence from the bottom to the edge. The low-pressure gasification chamber (6) is further provided with baffles (7) arranged in a staggered manner below the rotating gasification disc (5).

2. The air intake device of claim 1, wherein The diameter of the rotating gasification disc (5) is 5-50 cm, and the rotating speed is 50-5000 rpm.

3. The air intake device of claim 1, wherein The low-pressure uniform gas tank (11) is provided with an injection position of carrier gas and a carrier gas control device (17).

4. The air intake device of claim 1, wherein The low-pressure uniform gas tank (11) is provided with baffles arranged in a staggered manner.

5. A method of using the gas inlet device of a silicon carbide chemical vapor deposition furnace according to any one of claims 1 to 4, characterized by, The control switch in the device is turned on, the liquid MTS in the MTS storage tank (1) is sequentially introduced into the low-pressure uniform gas tank (11) through the preheating device (4) and the low-pressure gasification chamber (6), is uniformly mixed with the carrier gas injected into the low-pressure uniform gas tank (11), and the mixed gas is output from the low-pressure uniform gas tank (11) and input into the reaction chamber (15) to perform deposition work; the liquid MTS is rapidly gasified in the low-pressure gasification chamber (6), and the input amount of MTS is controlled in real time through the liquid flow control device (3).

6. The method of use of claim 5, wherein, The flow control of the liquid flow control device (3) is 1-10 ml / min.

7. The method of use of claim 5, wherein, The preheating temperature of the preheating device (4) is 30-60℃.

8. The method of use of claim 5, wherein, The actual heating temperature of the rotating gasification disc (5) is 30-80℃.

9. The method of use of claim 5, wherein, The pressure of the low-pressure gasification chamber (6) is controlled to be 500-3000 Pa, and the pressure of the low-pressure uniform gas tank (11) is higher than that of the low-pressure gasification chamber (6) by 0.5-50 KPa.

Images