Electronic grade tetramethylsilane filling system and processing method

Abstract

The present application relates to a kind of electronic grade tetramethylsilane filling system, including raw material tank, gas purification structure, gas-liquid separator, liquid purifier and cylinder, the present application also relates to processing method, the processing method of electronic grade tetramethylsilane filling system described in the present application, by raw material tank liquid gasification, the removal of oxygen, carbon dioxide and particulate matter and other impurities in 4MS gas is completed by gas purification structure, and then by gas-liquid separator, gas is converted into liquid, by liquid purifier, metal ions are removed, secondary filling treatment is completed, that is, the purity of ≥99.99% ultra-pure tetramethylsilane can be obtained.The filling method reduces the influence of filling power, and can improve the purity of tetramethylsilane during filling.The present application is simple in design, and the purpose of high purity of tetramethylsilane after filling and reducing the influence of intermediate impurities is realized under the synergistic effect of two-stage purifier.

Description

Technical Field

[0001] The present invention relates to the field of low-temperature liquid filling (fine chemical technology), and in particular to an electronic-grade tetramethylsilane filling system and a processing method. Background Art

[0002] Tetramethylsilane (4MS), with a boiling point of 26.5°C, is chemically stable and exhibits high thermal stability, only beginning to decompose at temperatures between 660°C and 720°C. Electronic-grade tetramethylsilane is used in semiconductor manufacturing processes for surface treatment during chemical vapor deposition (CVD) and physical vapor deposition (PVD). As a precursor for low-k thin film deposition, it is widely used in integrated circuit chip manufacturing, primarily in the 90nm and below technology node.

[0003] However, the semiconductor industry has extremely high requirements for the impurities in electronic-grade tetramethylsilane (4MS). Excessive levels of particulate matter, metal ions, and moisture in 4MS can severely impact the performance of components within the silicon wafer circuits, ultimately leading to circuit damage and even chip failure. Currently, the most common method for filling 4MS is liquid filling. However, the filling process involves high levels of metal ions, moisture, and particulate matter in the raw materials themselves. Furthermore, the disassembly and connection of raw material tanks, filling pipelines, and cylinders (tanks) can affect these levels, leading to difficulties in filling and high costs associated with failed fillings. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, the present invention aims to reduce impurity interference and further improve purity through an electronic grade tetramethylsilane filling system and processing method.

[0005] To achieve the above object, the present invention is implemented through the following technical solutions:

[0006] Preparation before filling: After the liquid surface space of the raw material tank is pumped to negative pressure, heat the raw material tank to a certain temperature. After confirming that the raw material tank reaches a certain pressure, open the raw material tank outlet valve and the gas-liquid separator inlet valve. 4MS passes through the gas purifier in the form of gas and enters the gas-liquid separator.

[0007] Filling: When the gas-liquid separator accumulates to a certain liquid level, open the gas-liquid separator outlet valve and let the liquid pass through the liquid purifier to reach the cylinder; when the cylinder filling volume is reached, close the cylinder valve to complete the filling.

[0008] Since the raw materials are passed through the gas purification structure in the form of gas to remove trace particles and impurities in the solution, and then passed through the liquid purifier in the form of liquid to remove trace metal ions in the solution, the particles and metal ions in the 4MS are effectively removed, reaching an order of magnitude higher electronic grade tetramethylsilane. Specifically:

[0009] An electronic-grade tetramethylsilane filling system comprises a raw material tank, which is connected to a gas-liquid separator through a pipeline, a raw material tank outlet valve and a raw material tank inlet valve are provided at the upper end of the raw material tank, a gas purification structure is provided between the raw material tank and the gas-liquid separator, a gas-liquid separator inlet valve is provided at the upper end of the gas-liquid separator, a gas-liquid separator outlet valve is provided at the lower end of the gas-liquid separator, the gas-liquid separator outlet valve is connected to a liquid purifier, a liquid purifier outlet valve is provided at the lower end of the liquid purifier, the liquid purifier outlet valve is connected to a cylinder through a cylinder liquid inlet end valve, a cylinder gas end valve is provided at the upper end of the cylinder, and the cylinder gas end valve is connected to a cylinder vacuum valve, a cylinder nitrogen valve, a vent valve and an analysis valve.

[0010] Preferably, the gas purification structure includes a shell, wherein a gas purifier and a VCR connector are installed in the shell, a VCR connector is installed in the front of the gas purifier, and a VCR connector is installed in the rear. The purifier air inlet is installed in the front of the shell, and the purifier air outlet is installed in the rear of the shell. The shell is made of stainless steel 316L, and the gas purifier is composed of adsorption filter material and filter element.

[0011] The liquid purifier comprises an outer shell and an inner surface, and both the outer shell and the inner surface of the liquid purifier are made of pure polytetrafluoroethylene.

[0012] The gas purification structure connector type selected by the present invention adopts VCR, which is adsorbed by activated carbon or molecular sieve and then filtered through a terminal filter element for nano-scale particulate matter. The liquid purifier includes a shell and a unique surface-modified pure PTFE matrix. This matrix is ​​combined with ion exchange groups to spontaneously and rapidly remove metal ions. During operation, due to the different solubility of impurities, the 4MS liquid contains different levels of oxygen, carbon dioxide and other impurities. Oxygen, carbon dioxide and other impurities in the solution are effectively removed by gasification through the gas purification structure, and then further removed by the terminal filter element. Compared with the liquid filling and filtration method, its purity is not only significantly improved, but also the particulate matter in the liquid is significantly reduced. The liquid purifier used later can further reduce the metal ions in the solution, thereby improving the purity of the product 4MS.

[0013] A method for treating an electronic-grade tetramethylsilane filling system comprises the following steps:

[0014] S1: After closing the outlet valve and inlet valve of the raw material tank, the raw material in the raw material tank is heated by a heating tape to maintain a constant temperature. After reaching a certain pressure, the outlet valve of the raw material tank and the inlet valve of the gas-liquid separator are opened. The gas passes through the outlet valve of the raw material tank, the gas purification structure and the inlet valve of the gas-liquid separator and reaches the gas-liquid separator;

[0015] S2: The gas-liquid separator cools the tetramethylsilane gas to liquid by cooling liquid, and when the gas-liquid separator reaches a certain liquid level, the next step is prepared;

[0016] S3: The cylinder pressure is extracted to a negative pressure of -0.1 MPa through the cylinder gas end valve and the cylinder vacuum valve, and after 30 s, the cylinder vacuum valve is closed, the cylinder nitrogen valve is opened, and after the cylinder pressure reaches 0.1 MPa, it is maintained for 30 s, and then the cylinder nitrogen valve is closed; the above operation is repeated 3 times, and after analysis, the cylinder is maintained in a vacuum negative pressure state, the pressure is -0.1 MPa or below, and the next step is performed;

[0017] S4: The gas-liquid separator outlet valve, the liquid purifier outlet valve and the cylinder liquid inlet valve are opened, and under the action of pressure and gravity, the liquid is filled into the cylinder through the gas-liquid separator outlet valve, the liquid purifier and the cylinder liquid inlet valve, and the filled ultrapure tetramethylsilane is obtained.

[0018] Preferably, in S1, the raw material tank heating temperature is 10-50℃, and the raw material tank gasification pressure is 0.3-0.8MPa when the raw material tank gas outlet valve and the gas-liquid separator gas inlet valve are opened.

[0019] Preferably, in S2, the cooling liquid temperature is -60-0℃, and the certain liquid level is 1 / 4-3 / 4 of the volume of the gas-liquid separator.

[0020] Preferably, in S4, the cylinder pressure is -0.1-0.3MPa.

[0021] Preferably, before the gas-liquid separator, the tetramethylsilane removes particulate matter, moisture and oxygen impurities through the gas purification structure; and after passing through the gas-liquid separator, the liquid purifier removes metal ion impurities.

[0022] Preferably, in S1, the purity of the raw material tetramethylsilane is ≥99.9%; and the metal ion purity of the raw material tetramethylsilane is 5N.

[0023] Preferably, in S4, the purity of the ultrapure tetramethylsilane is ≥99.99%.

[0024] The electronic grade tetramethylsilane filling system processing method provided by the application removes oxygen, carbon dioxide and particulate matter and other impurities in the 4MS gas through raw material tank liquid gasification and gas purification structure, and then converts the gas into liquid through the gas-liquid separator, removes metal ions through the liquid purifier, and completes the secondary filling treatment, so that ultrapure tetramethylsilane with a purity of ≥99.99% can be obtained. The filling method reduces the influence of filling power and improves the purity of tetramethylsilane during the filling process.

[0025] The beneficial effects of the application are as follows:

[0026] The present invention features a simple design and strong operability. The synergistic effect of the two-stage purifier ensures high purity of tetramethylsilane after filling, reduces safety risks associated with filling, saves costs, and facilitates large-scale filling. The resulting product meets the semiconductor industry's requirements for ultrapure tetramethylsilane, effectively ensuring and improving the quality stability and yield of semiconductor products, thereby achieving greater economic benefits and meeting market demand.

[0027] The present invention achieves high purity of tetramethylsilane after filling and reduces the impact of intermediate impurities through the synergistic effect of a two-stage purifier. The main impurities in the filling process come from impurities such as particulate matter and oxygen present in the raw materials, as well as metal ions, moisture, and particulate matter introduced during the disassembly and connection of the raw material tank, filling pipeline, and cylinder. This process first purifies the tetramethylsilane raw material by heating and vaporizing it using a gas purification structure, thereby reducing the impurity content in the tetramethylsilane. After liquefaction, the liquid purifier reduces the metal ion content to produce ultra-pure tetramethylsilane. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a filling process flow chart of the present invention.

[0029] Figure 2 Schematic diagram of the gas purification structure of the present invention.

[0030] Description of reference numerals:

[0031] 1-Raw material tank, 2-Gas purification structure, 3-Gas-liquid separator, 4-Liquid purifier, 5-Steel cylinder;

[0032] 21-purifier air inlet, 22-VCR connector, 23-housing, 24-gas purifier, 26-purifier air outlet, 31-coolant;

[0033] V1: Raw material tank outlet valve, V2: Gas-liquid separator air inlet valve, V3: Gas-liquid separator outlet valve, V4: Liquid purifier outlet valve, V5: Cylinder liquid inlet valve, V6: Cylinder gas end valve, V7: Cylinder vacuum valve, V8: Cylinder nitrogen valve, V9: Vent valve, V10: Analysis valve. DETAILED DESCRIPTION

[0034] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0035] System Example

[0036] like Figure 1-2An electronic grade tetramethylsilane filling system, comprising a raw material tank 1, the raw material tank 1 is communicated with a gas-liquid separator 3 through a pipeline, the raw material tank 1 is provided with a raw material tank gas outlet valve V1 and a raw material tank gas inlet valve on the upper end, a gas purification structure 2 is arranged between the raw material tank 1 and the gas-liquid separator 3, the gas-liquid separator 3 is provided with a gas-liquid separator gas inlet valve V2 on the upper end, the gas-liquid separator 3 is provided with a gas-liquid separator outlet valve V3 on the lower end, the gas-liquid separator outlet valve V3 is connected with a liquid purifier 4, the liquid purifier 4 is provided with a liquid purifier outlet valve V4 on the lower end, the liquid purifier outlet valve V4 is communicated with a cylinder 5 through a cylinder liquid inlet end valve V5, the cylinder 5 is provided with a cylinder gas end valve V6 on the upper end, the cylinder gas end valve V6 is communicated with a cylinder vacuum valve V7, a cylinder nitrogen valve V8, a vent valve V9 and an analysis valve V10. The cooling liquid 31 cools the gas-liquid separator 3, the cylinder vacuum valve V7 is connected with a vacuum pump, the cylinder nitrogen valve V8 is connected with nitrogen, the vent valve V9 is connected with the atmosphere, and the analysis valve V10 is connected with an analysis instrument,

[0037] The gas purification structure 2 comprises a shell 23, the shell 23 is internally provided with a gas purifier 24 and a VCR joint 22, the gas purifier 24 is provided with a VCR joint 22 in front and a VCR joint 22 at the back, the shell 23 is provided with a purifier gas inlet 21 at the front, and the shell 23 is provided with a purifier gas outlet 26 at the back, the shell 23 is made of stainless steel 316L, and the gas purifier 24 is internally composed of adsorption filter material and filter cores;

[0038] The liquid purifier 4 comprises an outer shell and an inner surface, and the outer shell of the liquid purifier 4 and the inner surface of the liquid purifier 4 are made of pure polytetrafluoroethylene material.

[0039] As Figure 2 The tetramethylsilane gas passes through the gas purification structure 2, sequentially passes through the purifier gas inlet 21, the VCR joint 22, the gas purifier 24, the VCR joint 22 and the purifier gas outlet 26 to complete the purification and filtration of the gas, wherein the shell 23 is made of stainless steel 316L, the gas purifier is internally composed of adsorption filter material and filter cores, the adsorption filter material adsorbs impurities such as oxygen and carbon monoxide, and the end filter core removes small particles, thereby completing the purification of the raw material; the liquid purifier comprises an outer shell and a specific surface modified pure PTFE matrix.

[0040] The following method embodiment applies the system of the system embodiment.

[0041] Method embodiment

[0042] Example 1

[0043] A method for processing an electronic-grade tetramethylsilane filling system comprises the following steps: using tetramethylsilane with a purity of ≥99.9% as raw material, heating the raw material tank to 25°C, and opening the raw material tank outlet valve V1 and the gas-liquid separator inlet valve V2 after the pressure reaches 0.6MPa. The gas passes through a gas purification structure and reaches the gas-liquid separator; the coolant is maintained at -30°C, and after the liquid level reaches 1 / 4 of the gas-liquid separator, the cylinder pressure is pumped down to a negative pressure of -0.1MPa through the cylinder gas end valve and the cylinder vacuum valve for 30 seconds; and the cylinder vacuum valve is closed. , open the nitrogen valve of the cylinder, wait for the cylinder pressure to reach 0.1MPa, maintain it for 30s, and then close the nitrogen valve of the cylinder; repeat the above operation to vacuum nitrogen 3 times. After the analysis is qualified, keep the cylinder in a vacuum negative pressure state with a pressure of -0.1MPa; open the gas-liquid separator outlet valve V3, the liquid purifier outlet valve V4 and the cylinder liquid inlet valve V5; after passing through the liquid purifier and flowing into the cylinder with a pressure of -0.09MPa, ultra-pure tetramethylsilane with a purity of 99.99% and a metal ion purity of 6N is obtained after filling.

[0044] Example 2

[0045] A method for processing an electronic-grade tetramethylsilane filling system comprises the following steps: using tetramethylsilane with a purity of ≥99.9% as a raw material, heating the raw material tank to 30°C, and opening the raw material tank outlet valve V1 and the gas-liquid separator inlet valve V2 after the pressure reaches 0.6 MPa. The gas passes through a gas purification structure and reaches the gas-liquid separator. The coolant is maintained at -30°C. After the liquid level reaches 1 / 4 of the gas-liquid separator, the cylinder pressure is pumped down to a negative pressure of -0.1 MPa through the cylinder gas end valve and the cylinder vacuum valve for 30 seconds. The cylinder vacuum valve is then closed. , open the nitrogen valve of the cylinder, wait for the cylinder pressure to reach 0.1MPa, maintain it for 30s, and then close the nitrogen valve of the cylinder; repeat the above operation to vacuum nitrogen 3 times. After the analysis is qualified, keep the cylinder in a vacuum negative pressure state with a pressure of -0.1MPa; open the gas-liquid separator outlet valve V3, the liquid purifier outlet valve V4 and the cylinder liquid inlet valve V5; after passing through the liquid purifier and flowing into the cylinder with a pressure of -0.09MPa, ultra-pure tetramethylsilane with a purity of 99.99% and a metal ion purity of 6N is obtained after filling.

[0046] Example 3

[0047] An electronic grade tetramethylsilane filling system processing method, taking purity ≥ 99.9% tetramethylsilane as raw material, heating the raw material tank to 40℃, opening the raw material tank outlet valve V1 and the gas-liquid separator inlet valve V2 after the pressure reaches 0.6MPa, reaching the gas-liquid separator through the gas purification structure, the cooling liquid is maintained at-30℃, after the liquid level reaches 1 / 4 of the gas-liquid separator; through the cylinder gas end valve and the cylinder vacuum valve, the cylinder pressure is extracted to negative pressure-0.1MPa, lasting for 30s; close the cylinder vacuum valve, open the cylinder nitrogen valve, after the cylinder pressure reaches 0.1MPa, lasting for 30s, close the cylinder nitrogen valve; repeat the above operation of vacuum nitrogen 3 times, after analysis, make the cylinder keep vacuum negative pressure state, the pressure is-0.1MPa; open the gas-liquid separator outlet valve V3, the liquid purifier outlet valve V4 and the cylinder liquid inlet valve V5; after filling into the cylinder with a pressure of-0.09MPa through the liquid purifier, ultra-pure tetramethylsilane with a purity of 99.99% and a metal ion purity of 6N is obtained.

[0048] Example 4

[0049] An electronic grade tetramethylsilane filling system processing method, taking purity ≥ 99.9% tetramethylsilane as raw material, heating the raw material tank to 40℃, opening the raw material tank outlet valve V1 and the gas-liquid separator inlet valve V2 after the pressure reaches 0.6MPa, reaching the gas-liquid separator through the gas purification structure, the cooling liquid is maintained at-30℃, after the liquid level reaches 1 / 4 of the gas-liquid separator; through the cylinder gas end valve and the cylinder vacuum valve, the cylinder pressure is extracted to negative pressure-0.1MPa, lasting for 30s; close the cylinder vacuum valve, open the cylinder nitrogen valve, after the cylinder pressure reaches 0.1MPa, lasting for 30s, close the cylinder nitrogen valve; repeat the above operation of vacuum nitrogen 3 times, after analysis, make the cylinder keep vacuum negative pressure state, the pressure is-0.1MPa; open the gas-liquid separator outlet valve V3, the liquid purifier outlet valve V4 and the cylinder liquid inlet valve V5; after filling into the cylinder with a pressure of-0.09MPa through the liquid purifier, ultra-pure tetramethylsilane with a purity of 99.99% and a metal ion purity of 6N is obtained.

[0050] Example 5

[0051] A processing method for an electronic-grade tetramethylsilane filling system uses tetramethylsilane with a purity of ≥99.9% as raw material, heats the raw material tank to 10°C, and opens the raw material tank outlet valve V1 and the gas-liquid separator inlet valve V2 after the pressure reaches 0.3MPa. The gas passes through a gas purification structure and reaches the gas-liquid separator. The coolant is maintained at -30°C. After the liquid level reaches 1 / 4 of the gas-liquid separator, the cylinder pressure is pumped down to a negative pressure of -0.1MPa through the cylinder gas end valve and the cylinder vacuum valve for 30 seconds. The cylinder vacuum valve is then closed. , open the nitrogen valve of the cylinder, wait for the cylinder pressure to reach 0.1MPa, maintain it for 30s, and then close the nitrogen valve of the cylinder; repeat the above operation to vacuum nitrogen 3 times. After the analysis is qualified, keep the cylinder in a vacuum negative pressure state with a pressure of -0.1MPa; open the gas-liquid separator outlet valve V3, the liquid purifier outlet valve V4 and the cylinder liquid inlet valve V5; after passing through the liquid purifier and flowing into the cylinder with a pressure of -0.09MPa, ultra-pure tetramethylsilane with a purity of 99.99% and a metal ion purity of 6N is obtained after filling.

[0052] Example 6

[0053] A method for processing an electronic-grade tetramethylsilane filling system comprises the following steps: using tetramethylsilane with a purity of ≥99.9% as a raw material, heating a raw material tank to 50°C, and opening the raw material tank outlet valve V1 and the gas-liquid separator inlet valve V2 after the pressure reaches 0.8 MPa. The gas passes through a gas purification structure and reaches the gas-liquid separator. The coolant is maintained at -30°C. After the liquid level reaches 2 / 4 of the gas-liquid separator, the cylinder pressure is pumped down to a negative pressure of -0.1 MPa through the cylinder gas end valve and the cylinder vacuum valve for 30 seconds. The cylinder is then closed. Vacuum valve, open the nitrogen valve of the cylinder, wait for the cylinder pressure to reach 0.1MPa, maintain it for 30s, and then close the nitrogen valve of the cylinder; repeat the above operation to vacuum nitrogen 3 times. After the analysis is qualified, keep the cylinder in a vacuum negative pressure state with a pressure of -0.1MPa; open the gas-liquid separator outlet valve V3, the liquid purifier outlet valve V4 and the cylinder liquid inlet valve V5; after the liquid purifier flows into the cylinder with a pressure of -0.09MPa, ultra-pure tetramethylsilane with a purity of 99.99% and a metal ion purity of 6N is obtained after filling.

[0054] Example 7

[0055] A method for processing an electronic grade tetramethylsilane filling system comprises the following steps: using tetramethylsilane with a purity of ≥99.9% as a raw material, heating the raw material tank to 30°C, opening the raw material tank outlet valve V1 and the gas-liquid separator inlet valve V2 after the pressure reaches 0.6MPa, and then passing through a gas purification structure to reach the gas-liquid separator. The coolant is maintained at -30°C, and after the liquid level reaches 3 / 4 of the gas-liquid separator; the cylinder pressure is pumped down to a negative pressure of -0.1MPa through the cylinder gas end valve and the cylinder vacuum valve for 30 seconds; the cylinder vacuum valve is closed, and the gas inlet valve V2 is opened. After the cylinder pressure reaches 0.1 MPa and remains at this level for 30 seconds, close the cylinder nitrogen valve; repeat the above operation to vacuum nitrogen three times. After the analysis is qualified, keep the cylinder in a vacuum negative pressure state at -0.1 MPa; open the gas-liquid separator outlet valve V3, the liquid purifier outlet valve V4, and the cylinder liquid inlet valve V5; after the liquid passes through the liquid purifier and flows into the cylinder at a pressure of -0.09 MPa, ultrapure tetramethylsilane with a purity of 99.99% and a metal ion purity of 6N is obtained after filling.

[0056] Example 8

[0057] A method for processing an electronic-grade tetramethylsilane filling system comprises the following steps: using tetramethylsilane with a purity of ≥99.9% as a raw material, heating the raw material tank to 30°C, and opening the raw material tank outlet valve V1 and the gas-liquid separator inlet valve V2 after the pressure reaches 0.6 MPa. The gas passes through a gas purification structure and reaches the gas-liquid separator. The coolant is maintained at -30°C. After the liquid level reaches 1 / 4 of the gas-liquid separator, the cylinder pressure is pumped down to a negative pressure of -0.1 MPa through the cylinder gas end valve and the cylinder vacuum valve for 30 seconds. The cylinder vacuum valve is then closed. , open the nitrogen valve of the cylinder, wait for the cylinder pressure to reach 0.1MPa, maintain it for 30s, and then close the nitrogen valve of the cylinder; repeat the above operation to vacuum nitrogen 3 times. After the analysis is qualified, keep the cylinder in a vacuum negative pressure state with a pressure of -0.1MPa; open the gas-liquid separator outlet valve V3, the liquid purifier outlet valve V4 and the cylinder liquid inlet valve V5; after passing through the liquid purifier and flowing into the cylinder with a pressure of -0.09MPa, ultra-pure tetramethylsilane with a purity of 99.99% and a metal ion purity of 6N is obtained after filling.

[0058] Example 9

[0059] The invention discloses a processing method for an electronic grade tetramethylsilane filling system, which uses tetramethylsilane with a purity of ≥99.9% as raw material, heats the raw material tank to 30°C, opens the raw material tank outlet valve V1 and the gas-liquid separator inlet valve V2 after the pressure reaches 0.6MPa, and reaches the gas-liquid separator through a gas purification structure, with the coolant maintained at 0°C. After the liquid level reaches 1 / 4 of the gas-liquid separator, the cylinder pressure is pumped down to a negative pressure of -0.1MPa through the cylinder gas end valve and the cylinder vacuum valve for 30 seconds; and the cylinder vacuum valve is closed. Empty the valve, open the nitrogen valve of the cylinder, wait for the cylinder pressure to reach 0.1MPa, maintain it for 30s, and then close the nitrogen valve of the cylinder; repeat the above operation to vacuum nitrogen 3 times. After the analysis is qualified, keep the cylinder in a vacuum negative pressure state with a pressure of -0.1MPa; open the gas-liquid separator outlet valve V3 and the liquid purifier outlet valves V4 and V5; after the liquid purifier flows into the cylinder with a pressure of -0.09MPa, ultra-pure tetramethylsilane with a purity of 99.99% and a metal ion purity of 6N is obtained after filling.

[0060] Example 10

[0061] A method for processing an electronic-grade tetramethylsilane filling system comprises the following steps: using tetramethylsilane with a purity of ≥99.9% as raw material, heating the raw material tank to 30°C, and opening the raw material tank outlet valve V1 and the gas-liquid separator inlet valve V2 after the pressure reaches 0.6MPa. The gas passes through a gas purification structure and reaches the gas-liquid separator. The coolant is maintained at -60°C. After the liquid level reaches 1 / 4 of the gas-liquid separator, the cylinder pressure is pumped down to a negative pressure of -0.1MPa through the cylinder gas end valve and the cylinder vacuum valve for 30 seconds. The cylinder vacuum valve is then closed. , open the nitrogen valve of the cylinder, wait for the cylinder pressure to reach 0.1MPa, maintain it for 30s, and then close the nitrogen valve of the cylinder; repeat the above operation to vacuum nitrogen 3 times. After the analysis is qualified, keep the cylinder in a vacuum negative pressure state with a pressure of -0.1MPa; open the gas-liquid separator outlet valve V3, the liquid purifier outlet valve V4 and the cylinder liquid inlet valve V5; after passing through the liquid purifier and flowing into the cylinder with a pressure of -0.09MPa, ultra-pure tetramethylsilane with a purity of 99.99% and a metal ion purity of 6N is obtained after filling.

[0062] The above are only preferred specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A method for treating an electronic grade tetramethylsilane filling system, characterized in that: The following steps are involved: S1: After closing the outlet valve and inlet valve of the raw material tank, the raw material in the raw material tank is heated by a heating tape and kept at a constant temperature. After reaching the pressure, the outlet valve of the raw material tank and the inlet valve of the gas-liquid separator are opened. The gas passes through the outlet valve of the raw material tank, the gas purification structure and the inlet valve of the gas-liquid separator and reaches the gas-liquid separator; S2: The gas-liquid separator cools the tetramethylsilane gas to liquid through the coolant. When the gas-liquid separator reaches the liquid level, it is ready to proceed to the next step. S3: Through the cylinder gas end valve and the cylinder vacuum valve, pump the cylinder pressure to a negative pressure of -0.1MPa, and maintain it for 30 seconds; close the cylinder vacuum valve, open the cylinder nitrogen valve, wait for the cylinder pressure to reach 0.1MPa, and then close the cylinder nitrogen valve after 30 seconds; repeat the above operation 3 times. After the analysis is qualified, keep the cylinder in a vacuum negative pressure state, with the pressure at -0.1MPa or below, and proceed to the next step; S4: Open the outlet valve of the gas-liquid separator, the outlet valve of the liquid purifier, and the valve at the liquid inlet end of the cylinder. Under the action of pressure and gravity, the liquid is filled into the cylinder through the outlet valve of the gas-liquid separator, the liquid purifier, and the valve at the liquid inlet end of the cylinder to obtain the filled ultra-pure tetramethylsilane; Before the gas-liquid separator, tetramethylsilane passes through a gas purification structure to remove particulate matter, moisture and oxygen impurities; after passing through the gas-liquid separator, it passes through a liquid purifier to remove metal ion impurities; The treatment method adopts an electronic grade tetramethylsilane filling system, which includes a raw material tank, which is connected to a gas-liquid separator through a pipeline, a raw material tank outlet valve and a raw material tank inlet valve are provided at the upper end of the raw material tank, a gas purification structure is provided between the raw material tank and the gas-liquid separator, a gas-liquid separator inlet valve is provided at the upper end of the gas-liquid separator, a gas-liquid separator outlet valve is provided at the lower end of the gas-liquid separator, the gas-liquid separator outlet valve is connected to a liquid purifier, a liquid purifier outlet valve is provided at the lower end of the liquid purifier, the liquid purifier outlet valve is connected to the cylinder through a cylinder liquid inlet end valve, a cylinder gas end valve is provided at the upper end of the cylinder, and the cylinder gas end valve is connected to the cylinder vacuum valve, cylinder nitrogen valve, vent valve and analysis valve.

2. The method for treating an electronic grade tetramethylsilane filling system according to claim 1, characterized in that: The gas purification structure includes a shell, in which a gas purifier and a VCR connector are installed. A VCR connector is installed in the front of the gas purifier and a VCR connector is installed in the back. The front of the shell is equipped with a purifier air inlet, and the rear of the shell is equipped with a purifier air outlet. The shell is made of 316L stainless steel. The interior of the gas purifier is composed of adsorption filter material and filter element. The liquid purifier comprises an outer shell and an inner surface, and both the outer shell and the inner surface of the liquid purifier are made of pure polytetrafluoroethylene.

3. The method for processing an electronic grade tetramethylsilane filling system according to claim 1, characterized in that: When the heating temperature of the raw material tank in S1 is 10~50℃ and the gasification pressure of the raw material tank is 0.3~0.8MPa, open the raw material tank outlet valve and the gas-liquid separator inlet valve.

4. The method for treating an electronic-grade tetramethylsilane filling system according to claim 1, characterized in that: The coolant temperature in S2 is -60~0°C, and the liquid level is 1 / 4~3 / 4 of the volume of the gas-liquid separator.

5. The method for treating an electronic grade tetramethylsilane filling system according to claim 1, characterized in that: The purity of the raw material tetramethylsilane used in S1 is ≥99.9%; the purity of the metal ion of the raw material tetramethylsilane used is 5N.

6. The method for treating an electronic grade tetramethylsilane filling system according to claim 1, characterized in that: The purity of tetramethylsilane in ultra-pure tetramethylsilane S4 is ≥99.99%.

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