Large-flow gas generator suitable for chemical vapor deposition equipment and supply method

Abstract

The invention discloses a high-flow gas generator suitable for chemical vapor deposition equipment and a supply method, and belongs to the technical field of gas semiconductor manufacturing. The butterfly valve is adopted to replace a traditional flow meter to supply flow, the defects of large resistance and small flow caused by the flow meter are overcome, further, the generator integrates vibration and heating device, using temperature and vibration coupling control, and closed-loop control of pressure is matched, so that the large-flow gas generator can be constantly at the target air pressure, and the flow rate is increased. The stable flow of gas can be supplied; furthermore, the air pressure, namely the flow, can rapidly reach the target flow through closed-loop control of the air pressure and a mature PID algorithm, high-precision control is achieved, and unification of the flow, the precision and the stability is achieved through the scheme.

Description

Technical Field

[0001] The invention relates to a large-flow gas suitable for chemical vapor deposition equipment and a supply method thereof, belonging to the technical field of gas semiconductor manufacturing. Background Art

[0002] Chemical Vapor Deposition (CVD) is a process used to prepare thin film materials in semiconductor and optoelectronic devices, while Atomic Layer Deposition (ALD) is essentially a CVD process with higher precision in film thickness and quality control. It achieves precise control of film thickness and composition by alternately introducing different chemical vapor precursors onto the substrate surface and utilizing chemical reactions to deposit materials layer by layer on the substrate. Its core lies in the self-limiting surface chemical reaction mechanism, in which only one layer of atoms is deposited in each reaction, so that a very uniform and dense film can be obtained.

[0003] Whether it is CVD or ALD process, raw material supply is a very important part. The stability, accuracy and flow rate of raw material supply will directly determine the quality of manufacturing materials. With the continuous development of semiconductor materials, their applications have penetrated into all walks of life, and the requirements for the quality of deposited films are getting higher and higher. Raw material supply, as one of the key factors affecting the quality of deposited films, has not received much attention. For example, the application of single-walled carbon nanotubes in battery slurry requires a large flow, high stability, and high precision gas carbon source supply to achieve high-quality growth of single-walled carbon nanotubes. The current carbon source supply method is the traditional flow meter method.

[0004] Although the traditional method of controlling flow with a flow meter can achieve high-precision control, it cannot achieve large-flow gas supply due to its own pipeline resistance (usually the pipeline of a high-precision flow meter is thinner, so it will produce its own pipeline resistance), and cannot meet the needs of industrial-grade semiconductor material manufacturing; other methods that can achieve large-flow supply cannot achieve high-stability and high-precision control. Therefore, the existing gas flow supply method cannot achieve the unity of flow, accuracy, and stability. Summary of the invention

[0005] In order to further ensure the deposition effect, the present invention provides a large-flow gas generator and supply method suitable for chemical vapor deposition equipment, which provides large-flow, high-stability and high-precision gas supply for thin film deposition or atomic-level material growth.

[0006] A high-flow gas supply method suitable for chemical vapor deposition equipment, the method is implemented based on a high-flow gas generator, the high-flow gas generator includes: a source bottle, a heating device, an atomizer, a pressure gauge and a controller; wherein the source bottle is used to store a gas source in a liquid state, the heating device and the atomizer are used to convert the gas source in the source bottle from a liquid state to a gas state, and the controller is used to adjust the heating device and the atomizer power according to the required flow rate to adjust the gas pressure in the source bottle. Optionally, in the high-flow gas generator, the heating device is arranged outside the source bottle, the atomizer is arranged inside the source bottle, the source bottle mouth is connected to the pressure gauge through a three-way valve, an angle valve is connected between the pressure gauge and the three-way valve, and the other passage of the three-way valve is connected to the gas supply pipeline through a butterfly valve, and the gas supply pipeline is connected to the vapor deposition chamber; the heating device, the atomizer, and the pressure gauge are all connected to the controller; the method includes: Step 1, for a gas source in a liquid state in a source bottle, calibrate the relationship between the pressure and flow rate in the source bottle; Step 2: determine the target pressure value in the source bottle according to the required flow rate, and use a PID algorithm to control the power of the heating device and the atomizer so that the pressure in the source bottle is stabilized at the target pressure value.

[0007] Optionally, the step 1 includes: Step 1.1: Place the gas source in liquid form in a source bottle, and adjust the power of the heating device and the atomizer to keep the gas pressure in the source bottle stable. kilopascals, the pressure in the vapor deposition chamber is evacuated to vacuum, the butterfly valve is opened to supply gas to the vapor deposition chamber at a certain gas flow rate for N time, and the pressure in the vapor deposition chamber is measured and recorded as ; Step 1.2: calibrate the mass flow meter with the flow rate as 标定 The pressure in the vapor deposition chamber is ; Step 1.3, use the following flow conversion formula to calculate the stable pressure in the source bottle Actual flow rate corresponding to the gas flow supply N time to the vapor deposition chamber in kPa :

[0008] in, 标定 is the gas flow rate of the calibration gas, which is a known quantity; 气体源 is the mass flow conversion coefficient of the gas source in liquid form stored in the source bottle, 标定 is the mass flow conversion coefficient of the calibration gas; Step 1.4, repeat steps 1.1 to 1.3 to obtain a stable pressure in the source bottle. Actual flow rate corresponding to the gas flow supply N time to the vapor deposition chamber in kPa , ≠ ; Step 1.5: The pressure inside the source bottle obtained according to Step 1.3 and Step 1.4 , The corresponding actual flow , Fitting to determine the parameters in the relationship between the pressure P and flow rate Q in the source bottle and :

[0009] in, represents the pressure in the source bottle, Q is the pressure in the source bottle The corresponding gas flow rate.

[0010] Optionally, the step 2 uses a PID algorithm to control the power of the heating device and the atomizer so that the pressure in the source bottle is stabilized before the pressure target value, and further includes: determining the relationship between the temperature provided by the heating device and the vibration power of the atomizer coupled with the liquid-gas conversion efficiency: The current power of the heating device is defined as: 加热 = 当前 2 汽化 ,in 当前 Indicates the current generator temperature. 汽化 Indicates the vaporization temperature of the liquid inside the source bottle; Define the power of the atomizer as 雾化 , then the overall generator current power is recorded as: 加热 雾化 ,in , are the power weight coefficients of the heating device and the atomizer respectively, and the power of the overall generator is adjusted Get the corresponding pressure.

[0011] Optional, , The value is determined according to the following method: The source bottle is heated to a temperature of , > 汽化 , adjust the atomizer power to half of its maximum power, recorded as 雾化1 ; After the pressure in the source bottle stabilizes, observe the pressure displayed on the pressure gauge. ; Keep the atomizer power unchanged and adjust the heating device to heat the source bottle to temperature , ≤2 汽化 , observe that the pressure gauge shows the air pressure is ; Turn the heat back to temperature , adjust the atomizer power to 雾化2 , 雾化2 雾化1 , observe that the pressure gauge shows the pressure is ; Then the corresponding:

[0012] Derived , :

[0013]

[0014] The heating device is a heating sleeve with a temperature display function, and its power can be adjusted automatically by adjusting its temperature.

[0015] Optionally, the calibration gas in step 1.2 is Ar / H 2 gas.

[0016] Optionally, the The value range is 1kPa to 3 kPa.

[0017] Optionally, the gas source in liquid state includes ethanol, methanol, and phenol.

[0018] The second object of the present invention is to provide a large-flow gas generator suitable for chemical vapor deposition equipment, wherein the large-flow gas generator comprises: a source bottle, a heating device, an atomizer, a pressure gauge and a controller; wherein the source bottle is used to store a gas source in a liquid state, the heating device and the atomizer are used to convert the gas source in the source bottle from a liquid state to a gas state, and the controller is used to adjust the power of the heating device and the atomizer according to the required flow rate to adjust the gas pressure in the source bottle.

[0019] Optionally, in the large-flow gas generator, the heating device is arranged outside the source bottle, the atomizer is arranged inside the source bottle, the mouth of the source bottle is connected to the pressure gauge via a three-way valve, an angle valve is connected between the pressure gauge and the three-way valve, the other passage of the three-way valve is connected to the gas supply pipeline via a butterfly valve, and the gas supply pipeline is connected to the vapor deposition chamber; the heating device, the atomizer, and the pressure gauge are all connected to the controller.

[0020] Optionally, the source bottle is made of stainless steel, glass, ceramic and Teflon.

[0021] The beneficial effects of the present invention are: 1. Large flow rate: The present invention adopts a butterfly valve to replace the traditional flow meter to supply flow, avoiding the disadvantages of large resistance and small flow rate brought by the flow meter. In addition, the generator integrates vibration and heating devices, which can promote the generation of gas source to the greatest extent.

[0022] 2. High stability: While ensuring a large flow rate, the present invention can achieve a stable supply of a large flow rate. The present invention uses temperature and vibration coupling control, and cooperates with closed-loop control of pressure to enable the large flow gas generator to be constant at the target gas pressure, that is, it can maintain its supply of a stable flow of gas.

[0023] 3. High precision: The present invention proposes a gas generation control method that couples temperature and vibration power to control the liquid-gas conversion efficiency. Higher-precision air pressure control is achieved through coupling control, and through closed-loop control of air pressure through a mature PID algorithm, the air pressure, i.e., flow rate, can quickly reach the target flow rate, thereby achieving high-precision control. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 This is a schematic diagram of the structure of a large-flow gas generator suitable for chemical vapor deposition equipment provided by the present invention, wherein 1-source bottle, 2-heating device, 3-atomizer, 4-three-way valve, 5-pressure gauge, 6-angle valve, 7-butterfly valve, 8-gas supply pipeline.

[0026] Figure 2 This is a comparison chart of the growth of single-walled carbon nanotubes when different flow rates of gas sources are introduced during the growth of single-walled carbon nanotubes.

[0027] Figure 3It is a comparison chart of gas flow supply for ethanol flow control using a conventional flow meter and using the large flow gas generator provided by the present invention.

[0028] Figure 4 This is a gas flow supply diagram for ethanol flow control using the large flow gas generator provided in this application.

[0029] Figure 5 The Raman spectra of single-walled carbon nanotubes grown by using the existing horiba flowmeter and the large flow gas generator provided by the present invention to provide a carbon source are compared. DETAILED DESCRIPTION

[0030] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] First, the conventional flow control method is introduced as follows: Existing ethanol flow supply method: Ethanol is used as a carbon source for atomic layer film deposition. The existing supply method is to control its supply flow through a flow tank with a flow meter, use the evaporation of ethanol itself to provide flow, and achieve flow control by setting flow meter parameters. In actual use, this control method has two major disadvantages. First, the self-evaporation ability of ethanol is limited. After a period of use, the flow rate often decreases and cannot reach the set flow rate (relevant studies have shown that ethanol concentration affects the evaporation mode and evaporation rate of droplets on super-hydrophobic surfaces. At low ethanol concentrations (≤20wt%), the droplet evaporation rate is slower and tends to the constant contact angle (CCA) mode, while at high ethanol concentrations (40wt%~60wt%), the droplet evaporation rate is faster and tends to the constant contact radius (CCR) mode. As ethanol evaporates, the concentration gradually decreases, which may cause the evaporation mode to change from the CCR mode to the CCA mode, thereby reducing the evaporation rate); second, the flowmeter itself will produce a lot of resistance to the pipeline. Even if the ethanol evaporation rate is increased by heating, the flowmeter itself cannot provide a large flow rate because of the pipeline resistance, that is, it cannot meet the requirements of large flow and high precision at the same time. The gas source flow rate will have a certain impact on the deposition effect of the thin film, please refer to Figure 2 , Figure 2 The three pictures from left to right are scanning electron microscope images of the growth of single-walled carbon nanotubes when the gas flow rate is 100sccm, 500sccm, and 800sccm. When other conditions remain unchanged, as the gas flow rate increases, it can be clearly found that the number of carbon tubes grown is obvious under the same scale of SEM (scanning electron microscope).

[0032] According to the above description of the existing carbon source supply method, it can be seen that the existing gas source supply method cannot provide a large flow supply. Therefore, the present application scheme abandons the conventional flow meter control flow scheme, innovatively proposes a scheme of using pressure control instead of flow control, and proposes a method of calibrating the relationship between pressure and flow, and then through atomization and heating coupling control, the gas pressure control is made more stable and accurate. Thus, a large flow, high stability, and high precision gas flow supply is achieved.

[0033] The high-flow supply solution provided by the present invention is also applicable to the supply of other liquid sources such as methanol and phenol.

[0034] Embodiment 1 This embodiment provides a large flow gas generator suitable for chemical vapor deposition equipment, see Figure 1 The large-flow gas generator includes a source bottle 1, a heating device 2 is arranged outside the source bottle 1, an atomizer 3 is arranged inside the source bottle 1, a pressure gauge 5 is connected to the mouth of the source bottle 1 through a three-way valve 4, an angle valve 6 is connected between the pressure gauge 5 and the three-way valve 4, and another passage of the three-way valve 4 is connected to a gas supply pipeline 8 through a butterfly valve 7; the gas supply pipeline 8 is connected to the chamber for depositing the thin film.

[0035] The high-flow gas generator can be applied to gas sources in liquid form, such as ethanol, methanol, phenol, etc. The following describes the control process of the high-flow gas generator by taking the deposition equipment as a tubular furnace as an example. The high-flow gas generator is used to provide an ethanol carbon source. The gas supply pipeline 8 of the high-flow gas generator is connected to the quartz tube chamber in the tubular furnace (considering the industry's expression habits, the subsequent mention of the pressure in the tubular furnace refers to the pressure in the quartz tube chamber). The gas supply pipeline 8 can use a bellows, and the heating device 2 can use a heating jacket. Based on the high-flow gas generator, a high-flow supply of the chemical vapor deposition process is realized, and the steps include: Step 1: Calibrate the relationship between flow and pressure; Step 1.1, place the gas source in liquid form in the source bottle 1, adjust the power of the heating device 2 and the atomizer 3 so that the gas pressure in the source bottle 1 is kept stable at kilopascals, pump the gas pressure in the tube furnace to vacuum, open the butterfly valve 7 to supply a certain gas flow rate to the tube furnace for N time, measure the pressure in the tube furnace, and record it as . The value range is usually 1kPa to 3kPa. Liquid gas sources include ethanol, methanol, phenol, etc.

[0036] Step 1.2: calibrate the mass flow meter with the flow rate as 标定 The calibration gas is also supplied for N time and the pressure in the tube furnace is ; In this embodiment, the calibration gas is Ar / H 2 Gas, of which H 2 The volume ratio is 3%. For the convenience of calculation, the mass flow meter can be calibrated to 1000sccm Ar / H 2 The pressure in the tube furnace after the gas flow rate is supplied for N time .

[0037] Step 1.3, use the following flow conversion formula to calculate the stable pressure in the source bottle The actual flow rate corresponding to the gas flow supply N time to the tube furnace in kPa :

[0038] in, 标定 is the gas flow rate of the calibration gas, which is a known quantity; 气体源 is the mass flow conversion coefficient of the gas source in liquid form stored in the source bottle, 标定 is the mass flow conversion factor of the calibration gas.

[0039] The mass flow conversion factor of a substance can usually be obtained by consulting relevant technical manuals, or by calculating it using the conversion factor calculation formula; the basic conversion factor calculation formula is:

[0040] in, is the density of the gas under standard conditions, is the constant pressure specific heat of the gas, It is the gas molecule composition coefficient, which is related to the components of the gas molecules.

[0041] If the calibration gas uses a mixed gas, the conversion factor calculation formula is:

[0042] in, , , , is the density of each gas in the mixed gas under standard conditions, , , , is the constant-pressure specific heat of each gas in the mixed gas, , , , is the gas molecule composition coefficient of each gas in the mixed gas; , , , is the flow rate of each gas in the mixed gas (which can be determined based on the proportion of each gas and the total flow rate), is the total flow rate of the mixed gas. In this embodiment, ethanol is used as the carbon source, Ar / H 2 The flow conversion formula for calibration gas is:

[0043] in, Ar / H 2 The mass flow conversion coefficient, C, is the ethanol mass flow conversion coefficient. For ease of calculation, in this embodiment The value is 1000 sccm, and other values ​​can be selected in practical applications.

[0044] In actual application scenarios, the gas calibrated in step 1.2 above can also be other gases, and the corresponding mass flow conversion coefficient This is the mass flow conversion coefficient of other gases. Usually, a gas with a known mass flow conversion coefficient can be selected as the calibration gas.

[0045] Step 1.4, repeat steps 1.1 to 1.3 to obtain a stable pressure in the source bottle. The actual flow rate corresponding to the gas flow supply N time to the tube furnace in kPa , .

[0046] Step 1.5: The pressure inside the source bottle obtained according to Step 1.3 and Step 1.4 , The corresponding actual flow , Fitting to determine the parameters in the relationship between the pressure P and flow rate Q in the source bottle and :

[0047] in, represents the pressure in the source bottle, Q is the pressure in the source bottle The corresponding gas flow rate.

[0048] Step 2: Control stress; According to the relationship between flow and pressure obtained by calibration in the first step above, controlling the pressure can control the flow. The second major advantage of this generator is that it can achieve stable and accurate flow control, that is, stable and accurate pressure control. The method is as follows: The present invention uses a closed-loop control, using a pressure gauge to monitor the pressure in the source bottle in real time. , the pressure in the source bottle is controlled by adjusting the atomizer and controlling the temperature of the generator. When the target pressure is greater than the current pressure, the PID controller reduces the atomizer power and the generator temperature accordingly; conversely, when the target pressure is less than the current pressure, the PID controller increases the atomizer power and the generator temperature accordingly. The closed-loop control process here can be implemented using the existing PID control theory, by adjusting the atomizer power and the power of the heating device to make the pressure in the source bottle Maintain at the preset value.

[0049] The specific control parameters of the PID controller are optimized by the corresponding technical personnel through experiments and adjustments according to the actual dynamic characteristics and control objectives. The specific adjustment process is not introduced in this embodiment.

[0050] The present invention also proposes a formula for controlling the liquid-vapor conversion efficiency by coupling temperature and vibration power. In the scheme of the present invention, the heating device is a heating sleeve with a temperature display function, and the corresponding target temperature can be directly set. The heating device automatically adjusts the power to reach the corresponding target temperature. Therefore, the temperature is directly used as one of the control variables in the scheme of the present invention.

[0051] Temperature and atomization control the liquid-to-gas conversion efficiency differently, so if you want to effectively and quickly control the temperature, you need to have reasonable control over the temperature and atomizer power. Assume that the current generator temperature is 当前 , the vaporization temperature of the liquid inside the source bottle is 汽化 , then the current power of the heating device can be approximately simplified as:

[0052] Assume that the current atomizer power is 雾化 , then the current power of the overall generator can be approximately approximated as:

[0053]

[0054] in , are the power weight coefficients of the heating device and the atomizer respectively. By adjusting the power of the overall generator The corresponding pressure can be obtained.

[0055] During the thin film deposition process, after the gas generator is connected to the corresponding system (in the thin film deposition scenario, the corresponding system here refers to the tube furnace), the source bottle is heated to a temperature of ( > 汽化), adjust the atomizer power to half of its maximum power, recorded as 雾化1 After the gas generator pressure (i.e. the pressure in the source bottle) stabilizes, observe the pressure displayed on the pressure gauge. Keep the atomizer power unchanged and adjust the heating device to heat the source bottle to temperature ( ≤2 汽化 ), observe that the pressure gauge shows the air pressure is ; Turn the heating temperature back to , adjust the atomizer power to 雾化2 , observe that the pressure gauge shows the pressure is ; then the corresponding:

[0056] Right now

[0057]

[0058] , Only suitable for temperatures and powers with larger flow outputs.

[0059] Embodiment 2 This embodiment provides a specific thin film deposition case: taking the preparation of single-walled carbon nanotubes as an example, the large-flow gas generator provided in the first embodiment is used to supply a gas source to achieve large-area single-walled carbon nanotube growth, and the gas source is ethanol.

[0060] In this embodiment, argon-hydrogen mixed gas containing 3% hydrogen is used as the calibration gas for calibration, and its mass flow conversion coefficient is 1.40, the mass flow conversion factor of ethanol is =0.39. When argon-hydrogen mixed gas is introduced for N=1 minute at 1000 sccm, the pressure in the furnace is =20.1 kPa. The pressure of the generator is controlled to =10 kPa. After ethanol gas is introduced for 1 minute, the pressure in the furnace is =14.2 kPa, then the ethanol flow rate corresponding to the pressure of 20 kPa is calculated according to the formula:

[0061] Using the same method, it is measured that when the generator pressure is 30 kPa, the flow rate is 3524 sccm, and the corresponding relationship between the pressure and the flow rate obtained by fitting is:

[0062] The unit of flow rate is sccm and the unit of pressure is kPa.

[0063] The corresponding formula for controlling the liquid-gas conversion efficiency by coupling the temperature and vibration power provided in Example 1 is calculated. =0.62, =0.38. When the pressure needs to be adjusted from 10 kPa to 15 kPa, the PLC will adjust the required power in real time through the PID algorithm. Assuming that the current required power is 60%, the atomizer power needs to be adjusted to 70.3% and the heating jacket power needs to be adjusted to 43.1%, that is, the heating jacket temperature needs to be adjusted to 67.5℃.

[0064] Figure 3 This is a comparison chart of gas flow supply when ethanol flow control is performed using a conventional flow meter and using the large-flow gas generator provided by the present invention. It can be seen that the corresponding pressure value is higher when the large-flow gas generator provided by the present invention is used to control the ethanol flow, that is, the large-flow gas generator provided by the present invention can provide a large-flow ethanol gas supply. Figure 4 The process of adjusting the gas pressure in the bottle from 8 kPa to 15 kPa when the large-flow gas generator provided by the present invention is used to provide a gas source. It can be seen that the pressure can be adjusted to 15 kPa after about 70 seconds of adjustment, and the corresponding flow rate is 2042 sccm, and the error can be stabilized within ±1%, that is, the present invention can provide a stable flow rate.

[0065] In order to further highlight the excellent performance of the high-flow gas generator provided by the present application in the chemical vapor deposition scenario, this embodiment also provides a comparison of the results of using an existing advanced flow controller (horiba flow meter) capable of providing a flow rate of 2000 sccm and using the high-flow gas generator provided by the present invention to provide a carbon source for the single-walled carbon nanotube growth process. Figure 5 The Raman spectrum of the corresponding grown single-walled carbon nanotubes shows that in the Raman spectrum of the single-walled carbon nanotubes using the large-flow gas generator provided by the present invention to supply the carbon source, the G / D ratio (i.e. the ratio of the G peak intensity to the D peak intensity) is 30, while the G / D ratio of the single-walled carbon nanotubes using the existing horiba flow meter to supply the carbon source is only 11. A high G / D ratio usually means that the material has better crystallinity and fewer lattice defects, that is, using the large-flow gas generator provided by the present invention to supply the carbon source can make the quality of the grown single-walled carbon nanotubes better.

[0066] Some steps in the embodiments of the present invention may be implemented using software, and the corresponding software program may be stored in a readable storage medium, such as a CD or a hard disk.

[0067] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-flow gas supply method suitable for chemical vapor deposition equipment, the method is implemented based on a high-flow gas generator, characterized in that: The large-flow gas generator comprises: a source bottle, a heating device, an atomizer, a pressure gauge and a controller; wherein the source bottle is used to store a gas source in a liquid state, the heating device and the atomizer are used to convert the gas source in the source bottle from a liquid state to a gas state, and the controller is used to adjust the power of the heating device and the atomizer according to the required flow rate to adjust the gas pressure in the source bottle.

2. The high-flow gas supply method according to claim 1, characterized in that: In the large-flow gas generator, the heating device is arranged outside the source bottle, the atomizer is arranged inside the source bottle, the mouth of the source bottle is connected to the pressure gauge through a three-way valve, an angle valve is connected between the pressure gauge and the three-way valve, the other passage of the three-way valve is connected to the gas supply pipeline through a butterfly valve, and the gas supply pipeline is connected to the vapor deposition chamber; the heating device, the atomizer, and the pressure gauge are all connected to the controller; the method comprises: Step 1, for a gas source in a liquid state in a source bottle, calibrate the relationship between the pressure and flow rate in the source bottle; Step 2: determine the target pressure value in the source bottle according to the required flow rate, and use a PID algorithm to control the power of the heating device and the atomizer so that the pressure in the source bottle is stabilized at the target pressure value.

3. The high-flow gas supply method according to claim 2, characterized in that: The step 1 comprises: Step 1.1: Place the gas source in liquid form in a source bottle, and adjust the power of the heating device and the atomizer to keep the gas pressure in the source bottle stable. kPa, the gas pressure in the vapor deposition chamber is evacuated to vacuum, the butterfly valve is opened to supply gas to the vapor deposition chamber at a certain gas flow rate for N time, and the pressure in the vapor deposition chamber is measured and recorded as ; Step 1.2: calibrate the mass flow meter with the flow rate as 标定 The pressure in the vapor deposition chamber is ; Step 1.3, use the following flow conversion formula to calculate the stable pressure in the source bottle Actual flow rate corresponding to the gas flow supply N time to the vapor deposition chamber in kPa : in, 标定 is the gas flow rate of the calibration gas, which is a known quantity; 气体源 is the mass flow conversion coefficient of the gas source in liquid form stored in the source bottle, 标定 is the mass flow conversion coefficient of the calibration gas; Step 1.4, repeat steps 1.1 to 1.3 to obtain a stable pressure in the source bottle. The actual flow rate Q2 corresponding to the gas flow supply N time to the vapor deposition chamber in kPa, ≠ ; Step 1.5: The pressure inside the source bottle obtained according to Step 1.3 and Step 1.4 , The corresponding actual flow , Fitting to determine the parameters in the relationship between the pressure P and flow rate Q in the source bottle and : in, represents the pressure in the source bottle, Q is the pressure in the source bottle The corresponding gas flow rate.

4. The high-flow gas supply method according to claim 3, characterized in that: The step 2 uses a PID algorithm to control the power of the heating device and the atomizer so that the pressure in the source bottle is stabilized before the pressure target value, and also includes: determining the relationship between the temperature provided by the heating device and the vibration power of the atomizer coupled with the liquid-gas conversion efficiency: The current power of the heating device is defined as: 加热 = 当前 2 汽化 ,in 当前 Indicates the current generator temperature. 汽化 Indicates the vaporization temperature of the liquid inside the source bottle; Define the power of the atomizer as 雾化 , then the overall generator current power is recorded as: 加热 雾化 ,in , are the power weight coefficients of the heating device and the atomizer respectively, and the power of the overall generator is adjusted Get the corresponding pressure.

5. The high-flow gas supply method according to claim 4, characterized in that: The power weight coefficients of the heating device and the atomizer , The value is determined according to the following method: The source bottle is heated to a temperature of , > 汽化 , adjust the atomizer power to half of its maximum power, recorded as 雾化1 ; After the pressure in the source bottle stabilizes, observe the pressure displayed on the pressure gauge. ; Keep the atomizer power unchanged and adjust the heating device to heat the source bottle to temperature , ≤2 汽化 , observe that the pressure gauge shows the air pressure is ; Turn the heat back to temperature , adjust the atomizer power to 雾化2 , 雾化2 雾化1 , observe that the pressure gauge shows the pressure is ; but , They are: The heating device is a heating sleeve with a temperature display function, and its power can be adjusted automatically by adjusting its temperature.

6. The high-flow gas supply method according to claim 5, characterized in that: In the step 1.2, the calibration gas is Ar / H2 gas.

7. The high-flow gas supply method according to claim 6, characterized in that: Said The value range is 1kPa to 3kPa.

8. The high-flow gas supply method according to claim 7, characterized in that: The gas source in liquid state includes ethanol, methanol and phenol.

9. A high-flow gas generator suitable for chemical vapor deposition equipment, characterized in that: The large-flow gas generator comprises: a source bottle, a heating device, an atomizer, a pressure gauge and a controller; wherein the source bottle is used to store a gas source in a liquid state, the heating device and the atomizer are used to convert the gas source in the source bottle from a liquid state to a gas state, and the controller is used to adjust the power of the heating device and the atomizer according to the required flow rate to adjust the gas pressure in the source bottle.

10. The high flow gas generator according to claim 9, characterized in that: In the large-flow gas generator, the heating device is arranged outside the source bottle, the atomizer is arranged inside the source bottle, the mouth of the source bottle is connected to the pressure gauge through a three-way valve, an angle valve is connected between the pressure gauge and the three-way valve, and the other passage of the three-way valve is connected to the gas supply pipeline through a butterfly valve, and the gas supply pipeline is connected to the vapor deposition chamber; the heating device, the atomizer, and the pressure gauge are all connected to the controller.

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