An atomic layer deposition gas supply method for a low-saturation vapor pressure precursor source

Abstract

The application discloses a kind of atomic layer deposition gas supply methods for low saturated vapor pressure precursor source, belong to atomic layer deposition reaction equipment technical field.The system is combined with original inlet gas pneumatic valve by mass flow controller, realizes the accurate control to the gas amount in the precursor source bottle in deposition process;And through pressure gauge, the pressure inside the precursor source bottle is monitored in real time, realizes the accurate control to temperature in deposition process;In addition, the specific content of precursor source gas and auxiliary gas in source outlet gas is monitored in real time by gas analyzer of source outlet, so as to assist system to judge whether reaction gas needs to be supplemented;Mass flow controller, pressure gauge and gas analyzer are connected with PLC controller, and the control of each part is realized by PLC controller;Realize that low saturated vapor pressure precursor source carries out gas control, pressure monitoring and component monitoring in experimental process.

Description

TECHNICAL FIELD

[0001] The present application relates to an atomic layer deposition gas supply method for a low-saturation-vapor-pressure precursor source, and belongs to the technical field of atomic layer deposition reaction equipment. BACKGROUND

[0002] Atomic layer deposition technology is a special chemical vapor deposition technology. In the process, two different precursor sources are alternately introduced into a heated vacuum chamber (also known as a reaction chamber), so that the precursor sources are alternately saturated chemisorbed on the surface of a substrate, thereby growing a thin film with an atomic layer thickness in a self-limiting manner. Atomic layer deposition technology has the advantages of low-temperature deposition, high thin film purity, and high coverage, and is suitable for thin film preparation in different temperature environments. In addition, the technology is highly controllable, and the generated thin film has good uniformity, and plays an increasingly important role in semiconductor manufacturing and new energy technology.

[0003] In an ideal atomic layer deposition reaction, the precursor needs to enter the vacuum chamber in the form of a gas-phase reactant. Therefore, the most important parameter for the precursor source used in atomic layer deposition reactions is the saturation vapor pressure. Saturation vapor pressure refers to the pressure of the vapor in equilibrium with a solid or liquid at a certain temperature in a closed condition. The same substance has different saturation vapor pressures at different temperatures, and the saturation vapor pressure increases with increasing temperature. For the same substance, the saturation vapor pressure of the solid state is less than that of the liquid state. In a classic atomic layer deposition reaction process for depositing an aluminum oxide thin film using trimethylaluminum and water as precursors, both trimethylaluminum and water have a high saturation vapor pressure, so the reaction can be carried out without heating the precursor source. However, with the development of atomic layer deposition technology, the types of thin films to be deposited are also increasing, and therefore the types of precursor sources developed are also increasing. However, not every type of precursor source has a high saturation vapor pressure like trimethylaluminum and water. Therefore, in order to improve the volatility of the precursor source, the precursor source needs to be heated. For example, Chinese Patent No. CN218321627U discloses an atomic layer deposition equipment and a source bottle heating device of the atomic layer deposition equipment. The heating device is designed to fit the source bottle to achieve good heating effect, and the split design makes disassembly more convenient.

[0004] However, for the precursor source with very low saturated vapor pressure, in order to make the precursor source fully gasified and volatilized, it is usually necessary to heat the precursor source to a high temperature, and in order to prevent the precursor source from condensing in the manual valve, the manual valve on the precursor source cylinder is usually heated during the heating process. However, the manual valve of the precursor source cylinder usually adopts a diaphragm valve, and the diaphragm valve has a low temperature resistance, usually around 120 DEG C. Therefore, when the heating temperature of the precursor source is too high, the manual valve will be irreversibly damaged, resulting in the loss of sealing function of the manual valve of the precursor source cylinder. In order to reduce the heating temperature of the precursor source, a source bottle applied to atomic deposition equipment is disclosed in Chinese patent CN103710683A. By inserting a bubbling tube into the source bottle and introducing an auxiliary gas into the bubbling tube, the auxiliary gas enters the source bottle through the bubbling tube and drives the precursor source to volatilize towards the outlet. By expanding the contact area between the carrier gas and the liquid source, the carrying efficiency of the carrier gas is improved while the invalid loss of the liquid source is reduced, and the liquid source resources are saved.

[0005] However, the above-mentioned bubbling type source bottle and heating device still have the following problems in actual use, which leads to unstable and ineffective gas supply:

[0006] (1) Lack of effective gas control system, unable to control the amount of auxiliary gas entering the source bottle during deposition and keep it stable;

[0007] (2) Lack of effective pressure monitoring system, unable to determine the appropriate heating temperature required for deposition;

[0008] (3) Lack of effective component monitoring system, unable to determine whether the volatilized gas is auxiliary gas or precursor source itself, and even if a pressure detection device is added to the existing gas supply system, it is impossible to distinguish the gas components and ensure effective gas supply. SUMMARY

[0009] In order to solve the problems in the prior art, the present application provides an atomic layer deposition gas supply system for low saturated vapor pressure precursor source. By improving the existing gas supply system, real-time monitoring of the precursor source entering the reaction chamber is realized. Under the premise of ensuring the supply amount of the precursor source, the amount of carrier gas entering the carrier assisted precursor source bottle can be accurately controlled, and the pressure inside the precursor source bottle can be monitored in real time during the experiment, which is convenient for determining the heating temperature of the precursor source. In addition, the gas components of the outlet can be monitored in real time during the experiment, which is convenient for judging the content of auxiliary gas and precursor source itself in the gas flowing out of the outlet.

[0010] A kind of atomic layer deposition gas supply system for low saturated vapor pressure precursor source, for providing gaseous precursor to atomic layer deposition equipment reaction cavity, comprising: carrier gas assisted precursor source bottle, heating device, precursor source pressure gauge, gas analyzer, auxiliary gas storage tank and PLC controller;

[0011] Wherein, heating device is used to heat the precursor source in carrier gas assisted precursor source bottle, precursor source pressure gauge is used to monitor pressure in carrier gas assisted precursor source bottle in real time, gas analyzer is used to analyze gas composition in carrier gas assisted precursor source bottle, auxiliary gas storage tank is used to store auxiliary gas, and PLC controller is used to control heating temperature of heating device and the amount of auxiliary gas into carrier gas assisted precursor source bottle according to pressure and gas composition in carrier gas assisted precursor source bottle.

[0012] Further, the atomic layer deposition gas supply system includes: carrier gas assisted precursor source bottle 1, flexible heating jacket 2, inlet manual valve 4, outlet manual valve 5, inlet pneumatic valve 7, PLC controller 8, auxiliary gas storage tank 9, storage pressure gauge 10, mass flow controller 11, carrier gas cylinder 12, vacuum pump 13, side extraction pneumatic valve 14, precursor source pressure gauge 15, gas analyzer 16, outlet pneumatic valve 17.

[0013] Carrier gas assisted precursor source bottle 1 (hereinafter referred to as source bottle 1) is provided with flexible heating jacket 2 outside, for heating source bottle 1 and then indirectly heating precursor source 3 inside source bottle 1 by heat conduction, source bottle 1 is provided with inlet and outlet above, inlet extends to the bottom of source bottle 1, and outlet extends to the top of source bottle 1, inlet is provided with inlet manual valve 4, and outlet is provided with outlet manual valve 5, inlet manual valve 4 and outlet manual valve 5 are used to realize sealing when source bottle 1 is installed and removed, to prevent precursor source 3 from deteriorating after contacting air.

[0014] Inlet side of inlet manual valve 4 is provided with inlet pneumatic valve 7, inlet pneumatic valve 7 is connected with PLC controller 8, and opening time of inlet pneumatic valve 7 can be accurately controlled by PLC controller 8, so as to accurately control the time of auxiliary gas entering source bottle 1.

[0015] Inlet side of inlet pneumatic valve 7 is provided with auxiliary gas storage tank 9, auxiliary gas storage tank 9 is provided with storage pressure gauge 10 outside, and is provided with mass flow controller 11, storage pressure gauge 10 and mass flow controller 11 are connected with PLC controller 8, the pressure of storage pressure gauge 10 can be monitored in real time by PLC controller 8, and the flow of mass flow controller 11 can be set by PLC controller 8.

[0016] The mass flow controller 11 is connected with a carrier gas cylinder 12, the carrier gas cylinder 12 is used for supplying carrier gas, the carrier gas is generally inert gas, such as nitrogen or argon. Between the auxiliary gas storage tank 9 and the inlet gas pneumatic valve 7, a bypass pipe connected to a vacuum pump 13 is arranged, the bypass pipe is provided with a bypass pneumatic valve 14, the bypass pneumatic valve 14 is connected with the PLC controller 8, the PLC controller 8 can accurately control the opening time of the bypass pneumatic valve 14, so as to discharge the excess storage gas in the auxiliary gas storage tank 9.

[0017] The precursor source pressure gauge 15 and the gas analyzer 16 are arranged outside the outlet gas manual valve 5, the precursor source pressure gauge 15 and the gas analyzer 16 are connected with the PLC controller 8, the pressure of the precursor source pressure gauge 15 can be monitored in real time through the PLC controller 8, the heating temperature of the source bottle 1 can be determined by comparing the pressure of the gas volatilized from the source bottle 1 and the saturated vapor pressure of the precursor source 3, the composition and content of the gas volatilized from the source bottle 1 can be monitored in real time through the PLC controller 8, and whether the content of the precursor source vapor in the mixed gas volatilized from the source bottle 1 is sufficient (which can be determined according to experience) can be determined, the outlet gas pneumatic valve 17 is arranged outside the precursor source pressure gauge 15 and the gas analyzer 16, the outlet gas pneumatic valve 17 is connected with the PLC controller 8, and the opening time of the outlet gas pneumatic valve 17 can be accurately controlled through the PLC controller 8, so as to accurately control the time when the mixture of the auxiliary gas and the precursor source vapor enters the reaction chamber 6.

[0018] Before the experiment, the vacuum pump 13 is started through the PLC controller 8, the system is kept in an extreme vacuum state, the outlet gas manual valve 5 is opened, the temperature of the flexible heating jacket 2 is set through the PLC controller 8, the pressure of the gas volatilized from the source bottle 1 is monitored through the precursor source pressure gauge 15, and the pressure is compared with the theoretical saturated vapor pressure of the precursor source 3, if the pressure is slightly greater than the theoretical saturated vapor pressure, the heating temperature is appropriate, and the next operation can be performed, if the pressure is less than the theoretical saturated vapor pressure, the heating temperature of the flexible heating jacket 2 needs to be increased through the PLC controller 8, and finally the appropriate heating temperature is determined.

[0019] It should be noted that in the process of setting the temperature, the temperature needs to be gradually increased from low to high to avoid exceeding the appropriate heating temperature. After the appropriate heating temperature is determined, the inlet gas manual valve 4 is opened, the pressure of the storage gas pressure gauge 10 is observed, the flow of the mass flow controller 11, the opening time of the inlet gas pneumatic valve 7, the opening time of the bypass pneumatic valve 14 and the opening time of the outlet gas pneumatic valve 17 are set through the PLC controller 8, so as to adjust the pressure of the storage gas pressure gauge 10 to an appropriate value, and then the pre-experiment is performed.

[0020] During the pre-experiment, the data monitored by the gas analyzer 12 is observed, and the opening time of the outlet pneumatic valve 17 is set by the PLC controller 8, so as to adjust the ratio of the carrier gas and the precursor source vapor in the gas volatilized from the source bottle 1.

[0021] After ensuring that the process is not problematic, other parameters such as the heating temperature of the pipeline, the valve and the reaction cavity are set by the PLC controller 8, so as to prevent the condensation of the precursor source 3 in the system, and then the formal experiment is carried out.

[0022] The beneficial effects of the present application are:

[0023] The atomic layer deposition gas supply method for the low-saturation-vapor-pressure precursor source provided by the present application can realize the accurate control of the gas amount entering the carrier gas assisted precursor source bottle by adding the mass flow controller, the auxiliary gas storage tank and the by-pass pneumatic valve, and combining with the original inlet pneumatic valve, so as to ensure the stability of the gas amount in the precursor source bottle; further, the present application adds the pressure gauge at the outlet of the carrier gas assisted precursor source bottle, so as to monitor the internal pressure of the source bottle in real time, and the appropriate heating temperature of the source bottle is determined by observing the pressure; further, the present application adds the gas analyzer at the outlet of the carrier gas assisted precursor source bottle, so as to monitor the composition of the outlet gas in real time, the content of the auxiliary gas and the precursor source vapor in the outlet gas is obtained by analyzing the composition of the gas by the analyzer, so as to determine whether the source amount is sufficient, thereby determining the next operation in the deposition reaction process. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0025] Figure 1 The schematic diagram of the atomic layer deposition gas supply system for the low-saturation-vapor-pressure precursor source provided by one embodiment of the present application is shown in the figure.

[0026] Figure 2 The schematic diagram of the PLC controller connection components in the atomic layer deposition gas supply system for the low-saturation-vapor-pressure precursor source provided by one embodiment of the present application is shown in the figure.

[0027] Figure 3 The flow chart of the atomic layer deposition gas supply method for the low-saturation-vapor-pressure precursor source provided by one embodiment of the present application is shown in the figure.

[0028] Wherein, 1, carrier gas assisted precursor source bottle, 2, flexible heating jacket, 3, precursor source, 4, inlet gas manual valve, 5, outlet gas manual valve, 6, reaction cavity, 7, inlet gas pneumatic valve, 8, PLC controller, 9, auxiliary gas storage tank, 10, gas storage pressure gauge, 11, mass flow controller, 12, carrier gas cylinder, 13, vacuum pump, 14, side extraction pneumatic valve, 15, precursor source pressure gauge, 16, gas analyzer, 17, outlet gas pneumatic valve. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical scheme and advantages of the present application more clear, the following will combine the drawings to make further detailed description to the embodiments of the present application.

[0030] Example one

[0031] The embodiment provides a kind of atomic layer deposition gas supply system for low saturated vapor pressure precursor source, and the system is provided with heating device for the precursor source with lower saturated vapor pressure, carrier gas device, also provided with gas analyzer and pressure gauge;Based on the gas pressure value and gas composition in the precursor source bottle, the heating power of heating device and the inlet gas pneumatic valve opening and closing time of carrier gas device are accurately controlled by PLC controller, realize the stable gas supply of low saturated vapor pressure precursor source, the gas supply system considers the resistant temperature of manual valve on precursor source bottle, determines appropriate heating temperature under the premise of guaranteeing stable gas supply.

[0032] As Figure 1 And Figure 2 The gas supply system includes precursor source bottle 1, flexible heating jacket 2, inlet gas manual valve 4, outlet gas manual valve 5, inlet gas pneumatic valve 7, PLC controller 8, auxiliary gas storage tank 9, gas storage pressure gauge 10, mass flow controller 11, carrier gas cylinder 12, vacuum pump 13, side extraction pneumatic valve 14, precursor source pressure gauge 15, gas analyzer 16, outlet gas pneumatic valve 17.

[0033] The precursor source bottle 1 is externally provided with a flexible heating sleeve 2 for heating the source bottle 1 and indirectly heating the precursor source 3 in the source bottle 1 through heat conduction. The source bottle 1 is provided with an air inlet and an air outlet. The air inlet is connected to an auxiliary gas storage tank 9 storing auxiliary gas through an air inlet pipe. The air outlet is connected to a reaction chamber 6 of an atomic layer deposition device through an air outlet pipe. The air inlet pipe extends to the bottom of the source bottle 1, and the air outlet pipe is located at the top of the source bottle 1. An air inlet manual valve 4 is arranged at the air inlet of the source bottle 1, and an air outlet manual valve 5 is arranged at the air outlet. The air inlet manual valve 4 and the air outlet manual valve 5 are used to realize sealing when the source bottle 1 is installed and removed, so as to prevent the precursor source 3 from deteriorating after contacting air. The air inlet pipe is used to transport auxiliary gas into the source bottle 1, and the air outlet pipe is used to transport the mixture of auxiliary gas and the precursor source 3 to the reaction chamber 6. An air inlet pneumatic valve 7 is arranged outside the air inlet manual valve 4 and connected to a PLC controller 8. The opening time of the air inlet pneumatic valve 7 is accurately controlled by the PLC controller 8, so as to accurately control the amount of auxiliary gas entering the source bottle 1 by accurately controlling the time of auxiliary gas entering the source bottle 1.

[0034] The auxiliary gas storage tank 9 is provided with a gas storage pressure gauge 10 and a mass flow controller 11 at the rear end. A carrier gas cylinder 12 is connected to the rear end of the mass flow controller 11. A bypass pipe connected to a vacuum pump 13 is arranged between the auxiliary gas storage tank 9 and the air inlet pneumatic valve 7. An air bypass pneumatic valve 14 is arranged on the bypass pipe. The gas storage pressure gauge 10 and the air bypass pneumatic valve 14 are connected to the PLC controller 8. The flow of the mass flow controller 11 and the opening time of the air bypass pneumatic valve 14 can be set by the PLC controller 8, so as to accurately control the amount of auxiliary gas stored in the auxiliary gas storage tank 9.

[0035] A precursor source pressure gauge 15 and a gas analyzer 16 are arranged on the pipeline between the air outlet manual valve 5 of the source bottle 1 and an air outlet pneumatic valve 17. The precursor source pressure gauge 15 and the gas analyzer 16 are connected to the PLC controller 8. In the open state of the air outlet manual valve 5, the PLC controller 8 can monitor the gas pressure in the source bottle 1 in real time through the precursor source pressure gauge 15, and the gas analyzer 16 can monitor the gas composition volatilized from the source bottle 1 in real time. The gas analyzer 16 is mainly used to determine the content of the precursor source vapor and the auxiliary gas in the mixed gas volatilized from the source bottle 1. The PLC controller adjusts the heating temperature of the flexible heating sleeve 2 and the air inlet amount of the auxiliary gas according to the pressure fed back by the precursor source pressure gauge 15 and the content ratio of the precursor source vapor in the mixed gas volatilized from the source bottle 1 fed back by the gas analyzer 16.

[0036] An air outlet pneumatic valve 17 is arranged outside the gas analyzer 16 and connected to the PLC controller 8. The opening time of the air outlet pneumatic valve 17 can be accurately controlled by the PLC controller 8, so as to accurately control the amount of mixed gas entering the reaction chamber 6.

[0037] Embodiment Two

[0038] The embodiment provides an atomic layer deposition gas supply method for a low-saturated-vapor-pressure precursor source, which is realized based on the gas supply system provided in Embodiment One, as shown in the figure, and the method comprises the following steps: Figure 3

[0039] Step 1, close the inlet and outlet gas pneumatic valves and the inlet gas manual valve, and open the outlet gas manual valve;

[0040] Step 2, heat the precursor source in the carrier-gas-assisted precursor source bottle by using the heating device, and the heating temperature is set as T1, T1 is set according to the experience value of the specific precursor source, and T1 < T0, T0 is the limit temperature that can be borne by the inlet and outlet gas manual valves;

[0041] Step 3, compare the precursor source pressure gauge value P1 with the saturated vapor pressure theoretical value P corresponding to the temperature T1, if P1 < P, increase the heating temperature of the heating device until the precursor source pressure gauge value is equal to or greater than the saturated vapor pressure theoretical value corresponding to the temperature after the increase, at this time, the temperature is recorded as T2, T2 ≤ T0, and T2 is determined as the final heating temperature;

[0042] If the precursor source pressure gauge value is still less than the saturated vapor pressure theoretical value corresponding to the temperature after the increase of the heating temperature of the heating device to T0, T0 is determined as the final heating temperature;

[0043] Step 4, after the final heating temperature is determined, open the inlet gas manual valve and the inlet gas pneumatic valve of the carrier-gas-assisted precursor source bottle, and introduce the carrier gas into the carrier-gas-assisted precursor source bottle; at the same time, open the outlet gas pneumatic valve to supply the reaction cavity with the carrier gas;

[0044] Step 5, during the gas supply process, analyze the gas composition in the carrier-gas-assisted precursor source bottle by using the gas analyzer, if the proportion of the precursor content is lower than the pre-set threshold value, reduce the opening time of the inlet gas pneumatic valve or close the inlet gas pneumatic valve by using the PLC controller.

[0045] The gas supply method is further introduced in combination with the actual deposition process as follows:

[0046] Reference Figure 3 Before the deposition experiment starts, first open the outlet gas manual valve 5, adjust the temperature of the flexible heating sleeve 2, monitor the gas pressure volatilized from the source bottle 1 by using the precursor source pressure gauge 15, and compare the gas pressure with the theoretical saturated vapor pressure corresponding to the specific precursor source 3 at the corresponding temperature, to determine the appropriate heating temperature, and the specific determination process is as follows:

[0047] ​First, the heating temperature of the flexible heating jacket 2 is set to T1 according to the experience value, T1 needs to be lower than the limit temperature that the inlet and outlet gas manual valve can withstand, the value of the precursor source pressure gauge 15 at this temperature is obtained, if the pressure monitored by the precursor source pressure gauge 15 is lower than the theoretical saturated vapor pressure of the precursor source 3, the heating temperature of the flexible heating jacket 2 needs to be further increased through the PLC controller 8 until the pressure monitored by the precursor source pressure gauge 15 reaches the theoretical saturated vapor pressure of the precursor source 3 at the corresponding temperature, and the appropriate heating temperature is finally determined. It needs to be noted that if the temperature is increased to the limit temperature T0 that the inlet and outlet gas manual valve can withstand, and the gas pressure volatilized from the source bottle 1 is still lower than the corresponding theoretical saturated vapor pressure at this temperature, the heating temperature will not be increased, and the carrier gas is used to speed up the volatilization degree of the precursor source at this heating temperature. In addition, during the process of gradually increasing the heating temperature, the temperature needs to be set from low to high step by step to avoid exceeding the appropriate heating temperature.

[0048] After determining the appropriate heating temperature, the flow rate of the mass flow controller 10 can be set through the PLC controller 8, and the pressure value of the gas storage pressure gauge 10 is observed. The specific flow rate value can be determined according to experience, and the relationship between the flow rate and the pressure value in the auxiliary gas storage tank can be determined according to experience. During the process of introducing the carrier gas, the pressure value of the gas storage pressure gauge 10 is compared with the pre-set pressure range in the auxiliary gas storage tank. If it is higher than the highest value of the pressure range, the flow rate of the mass flow controller 10 can be reduced through the PLC controller 8, and the opening time of the side suction pneumatic valve 14 is set through the PLC controller to make the excess gas be pumped away by the vacuum pump 13. If the pressure value of the gas storage pressure gauge 10 is lower than the lowest value of the pressure range, the flow rate of the mass flow controller 10 can be increased through the PLC controller 8, and the appropriate auxiliary gas storage amount is finally determined.

[0049] After determining the appropriate auxiliary gas storage amount, the inlet gas manual valve 4 can be opened, and the opening time of the inlet pneumatic valve 7 and the outlet pneumatic valve 17 is set through the PLC controller 8. The pressure value of the precursor source pressure gauge 15 and the gas analysis data of the gas analyzer 16 are observed. If the precursor source vapor content is not appropriate, the opening time of the inlet pneumatic valve 7 and the outlet pneumatic valve 17 can be adjusted until the precursor source vapor content reaches the appropriate value. It needs to be noted that the valve opening time needs to be set from short to long step by step to avoid exceeding the appropriate time length. It needs to be noted that the appropriate precursor source vapor content ratio can be determined according to the experiment or set according to the experience value. For example, by comparing the deposition under different precursor source vapor content ratios, the threshold value of the precursor source vapor content ratio is determined.

[0050] After ensuring that the process is not a problem, other conventional parameters can be set by the PLC controller 8, such as the heating temperature of the pipeline, valve, and reaction cavity, to prevent the precursor source 3 from condensing in the system, and then formal experiments are carried out.

[0051] In order to verify the effectiveness of the atomic layer deposition carrier gas assisted precursor source real-time monitoring system provided in the embodiment, two specific deposition processes are used for verification. One is a relatively mature process using tetrakisdimethylaminozirconium and water as precursor sources to deposit zirconium oxide film. The other is a process using tris (scandium N, N'-diisopropylformamide) (III) and ozone as precursor sources to deposit scandium oxide film, which has not been reported so far.

[0052] In the zirconium oxide process verification process, since tetrakisdimethylaminozirconium is a relatively mature precursor source, the appropriate heating temperature of the source bottle can be determined according to the recommended heating temperature and theoretical saturated vapor pressure provided by the precursor source manufacturer. In the specific experiment, the outlet gas manual valve 5 is opened, the temperature of the flexible heating sleeve 2 outside the source bottle 1 is gradually increased from room temperature by the PLC controller 8, and the pressure value of the precursor source pressure gauge 15 is observed. The pressure value is compared with the saturated vapor pressure provided by the precursor source manufacturer, and the appropriate heating temperature is finally determined to be 40°C. At this time, the pressure value of the precursor source pressure gauge 15 is 37.0 Pascal. Then the flow rate of the mass flow controller 11 is set to 5 sccm by the PLC controller, and the pressure of the gas storage pressure gauge 10 is observed. If the pressure is too high, the opening time of the side extraction pneumatic valve 14 is set by the PLC controller 8, and the excess carrier gas is extracted by the vacuum pump 13. The appropriate auxiliary gas storage amount is finally determined. Then the inlet gas manual valve 4 is opened, and the opening time of the inlet gas pneumatic valve 7 and the outlet gas pneumatic valve 5 is set. The pre-experiment is carried out. During the pre-experiment, the gas content of the gas analyzer 16 is observed, and it is observed that the precursor source vapor content in the mixed gas is reasonable. The reaction cavity heating temperature is set to 200°C by the PLC controller 8, the pipeline heating temperature is set to 150°C, and the valve heating temperature is set to 120°C to prevent the precursor source vapor from condensing when flowing through the pipeline and valve. Finally, the formal experiment of 200 cycles is carried out. The sample obtained by using the ellipsometer is tested, and the test result is that the film thickness is about 21 nanometers. According to the calculation, the deposition rate of the zirconium oxide film is about 0.11 nanometer per cycle.

[0053] In the process of verifying the scandium oxide, since the scandium (III) tris (N, N'-diisopropylformamide) is a precursor source that has not been reported, in the process of determining the heating temperature of the precursor source, the relevant data of the four dimethylamino zirconium is referred to. In the specific experiment, the outlet gas manual valve 5 is opened, and the temperature of the flexible heating jacket 2 outside the source bottle 1 is gradually increased from room temperature through the PLC controller 8, and the pressure value of the precursor source pressure gauge 15 is observed, and compared with the corresponding value of the four dimethylamino zirconium, when the temperature of the flexible heating jacket 2 is increased to 110 DEG C, the gas pressure in the source bottle is about 37.4 Pa, then the flow rate of the mass flow controller 11 is set to 5 sccm through the PLC controller 8, and it is found that the pressure is too low when the pressure of the gas storage pressure gauge 10 is observed, so the flow rate of the mass flow controller 11 is increased to 10 sccm, and the pressure is appropriate, and finally the appropriate auxiliary gas storage rate is determined, then the opening time of the inlet gas pneumatic valve 7 and the outlet gas pneumatic valve 5 is set, and the inlet gas manual valve 4 is opened, and the pre-experiment is carried out, in the pre-experiment process, the gas content of the gas analyzer 16 is observed, and it is observed that the content of the precursor source vapor in the mixed gas is low, then the opening time of the inlet gas pneumatic valve 7 and the outlet gas pneumatic valve 5 is adjusted through the PLC controller 8, and the content of the precursor source vapor in the mixed gas is continuously observed by the gas analyzer 16, and it is found that the content of the precursor source vapor is always low in this process, and it is speculated that the reason is that the saturated vapor pressure of the scandium (III) tris (N, N'-diisopropylformamide) and the four dimethylamino zirconium is different, so that when the pre-experiment is carried out by referring to the relevant data of the four dimethylamino zirconium, the ideal effect cannot be achieved, then the temperature of the flexible heating jacket 2 outside the source bottle 1 is increased, and the above steps are repeated, until the heating temperature is increased to 140 DEG C, the content of the precursor source vapor in the mixed gas monitored by the gas analyzer 16 is reasonable, the reaction cavity heating temperature is set to 300 DEG C, the pipeline heating temperature is set to 200 DEG C, and the valve heating temperature is set to 160 DEG C through the PLC controller 8, so as to prevent the condensation of the precursor source vapor when flowing between the pipeline and the valve, and finally the formal experiment of 500 cycles is carried out, the sample obtained by using the ellipsometer is tested, and the test result is that the film thickness is about 27 nm, and the deposition rate of the scandium oxide film is about 0.054 nm per cycle.

[0054] The above only describes the preferred embodiments of the present application, and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An atomic layer deposition gas supply method for a low-saturation-vapor-pressure precursor source, characterized by, The atomic layer deposition gas supply method is realized based on an atomic layer deposition gas supply system for a low-saturation-vapor-pressure precursor source, which comprises a carrier gas assisted precursor source bottle, a heating device, a precursor source pressure gauge, a gas analyzer, an auxiliary gas storage tank, a PLC controller, an inlet / outlet gas manual valve, an inlet / outlet gas pneumatic valve, a carrier gas bottle, a mass flow controller, a storage pressure gauge, a vacuum pump and a bypass pneumatic valve. The gas analyzer and the precursor source pressure gauge are arranged between the outlet gas manual valve and the outlet gas pneumatic valve of the precursor source bottle; the inlet gas pneumatic valve is arranged on the gas pipeline through which the carrier gas assisted precursor source bottle communicates with the auxiliary gas storage tank; the carrier gas bottle and the auxiliary gas storage tank are connected through a gas pipeline, the mass flow controller is arranged on the gas pipeline between the carrier gas bottle and the auxiliary gas storage tank, and the storage pressure gauge is used for detecting the pressure in the auxiliary gas storage tank; the vacuum pump is connected with the auxiliary gas storage tank through the bypass pneumatic valve; and the PLC controller controls the mass flow controller and the vacuum pump according to the value of the storage pressure gauge so that the pressure in the auxiliary gas storage tank is in a predetermined range. The method comprises the following steps: Step 1: closing the inlet / outlet gas pneumatic valve and the inlet gas manual valve, and opening the outlet gas manual valve; Step 2: heating the precursor source in the carrier gas assisted precursor source bottle by using the heating device, and setting the heating temperature as T1, wherein T1 is set according to the experience value of the specific precursor source, and T1 < T0, wherein T0 is the limit temperature that the inlet / outlet gas manual valve can withstand; Step 3: comparing the value P1 of the precursor source pressure gauge with the theoretical value P of the saturation vapor pressure corresponding to the temperature T1, if P1 < P, increasing the heating temperature of the heating device until the value of the precursor source pressure gauge is equal to or greater than the theoretical value of the saturation vapor pressure corresponding to the increased temperature, at this time, the temperature is recorded as T2, and T2 ≤ T0, and T2 is determined as the final heating temperature; if the value of the precursor source pressure gauge is still less than the theoretical value of the saturation vapor pressure corresponding to T0 after increasing the heating temperature of the heating device to T0, T0 is determined as the final heating temperature; Step 4: after determining the final heating temperature, opening the inlet gas manual valve and the inlet gas pneumatic valve of the carrier gas assisted precursor source bottle, and introducing carrier gas into the carrier gas assisted precursor source bottle; at the same time, opening the outlet gas pneumatic valve to supply gas to the reaction chamber; Step 5: during the gas supply process, analyzing the gas composition in the carrier gas assisted precursor source bottle by using the gas analyzer, and if the proportion of the precursor content is lower than the pre-set threshold value, reducing the opening time of the inlet gas pneumatic valve or closing the inlet gas pneumatic valve by using the PLC controller.

2. The method of claim 1, wherein the method further comprises: The method determines the gas flow of the mass flow controller according to the pressure in the auxiliary gas storage tank.

3. The method of claim 2, wherein the method further comprises: The method controls the gas flow to make the pressure in the auxiliary gas storage tank be in a predetermined pressure range, and the predetermined pressure range is set according to the experience value.

4. The method of claim 3, wherein the method further comprises: In the step 3, the heating temperature of the heating device is increased in a gradient manner.

5. An atomic layer deposition apparatus, characterized by, The atomic layer deposition device is used to realize the atomic layer deposition gas supply method according to any one of the preceding claims 1-4.

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