Germane gas collecting system

Abstract

The utility model relates to the technical field of germane gas, and provides a germane gas collecting system which can reduce the loss of germane products and enable germane to be separated more thoroughly. The system comprises a crude product gas conveying pipeline, an inert gas conveying pipeline, a gas collecting tank, a condensing tank, a product gas cylinder and a vacuum pump, the crude product gas conveying pipeline and the inert gas conveying pipeline are respectively communicated with a gas inlet of the gas collecting tank; a gas volume flow meter is arranged on the crude product gas conveying pipeline; the gas collecting tank is provided with a first freezing device; the gas collecting tank is provided with a pressure gauge; a gas outlet of the gas collection tank is communicated with a gas inlet of the condensation tank, the condensation tank is filled with a metal filler, a gas outlet of the condensation tank is communicated with a gas inlet of the product gas cylinder, and the gas outlet of the condensation tank is further communicated with the vacuum pump; the condensation tank is provided with a second freezing device; and each pipeline is provided with a valve.

Description

Technical Field

[0001] This utility model relates to the field of germane gas technology, and specifically to a germane gas collection system. Background Technology

[0002] Germanane is an important electronic gas in the semiconductor industry. As a precursor for chemical vapor deposition of silicon-germanium (Si-Ge) films, it can be used in the manufacture of integrated circuits and optoelectronic devices. Currently, the widely used industrial methods for preparing germanane are based on the following reaction:

[0003] GeO2+4NaBH4+2H2SO4+10H2O=GeH4+4H3BO3+12H2+2Na2SO4

[0004] Its main gaseous products are germane and hydrogen (with hydrogen accounting for over 80% by volume). The traditional method for collecting germane product gas involves passing the gas generated in the reaction into a liquid nitrogen-cooled collection tank to freeze and collect the germane gas. During this process, the collection tank needs to be evacuated multiple times to remove H2 before collection continues. However, in actual production, to improve efficiency, the liquid nitrogen freezing time for collecting germane product gas is limited, often resulting in incomplete freezing of the germane. This often leads to germane being carried away during H2 removal, causing losses of the germane product. Utility Model Content

[0005] To address at least one deficiency in the existing technology, this invention provides a germane gas collection system. By using the germane gas collection system provided by this invention to separate and collect germane in the crude germane product gas prepared by the upstream reaction, the loss of germane product can be reduced and the separation of germane can be more thorough.

[0006] To achieve its purpose, this utility model provides the following technical solution:

[0007] This utility model provides a germane gas collection system, the system including a crude product gas delivery pipeline for conveying crude germane product gas, an inert gas delivery pipeline, a gas collection tank, a condenser, a product gas cylinder and a vacuum pump;

[0008] The crude gas delivery pipeline and the inert gas delivery pipeline are respectively connected to the inlet of the gas collection tank; a gas volume flow meter is installed on the crude gas delivery pipeline; the gas collection tank is equipped with a first refrigeration device capable of condensing germane gas entering the gas collection tank; the gas collection tank is equipped with a pressure gauge;

[0009] The outlet of the gas collection tank is connected to the inlet of the condenser tank via a first outlet pipeline. The condenser tank is filled with metal packing material. The outlet of the condenser tank is connected to the inlet of the product gas cylinder via a second outlet pipeline. The outlet of the condenser tank is also connected to the vacuum pump via a third outlet pipeline. The condenser tank is equipped with a second refrigeration device capable of condensing germane gas entering the condenser tank.

[0010] Each of the pipelines is equipped with a valve.

[0011] Preferably, the gas collection tank has an inner cavity with a partition that divides the inner cavity of the gas collection tank into an inlet flow zone and an outlet flow zone. The inlet of the gas collection tank is located at the top or upper part of the inlet flow zone, and the outlet of the gas collection tank is located at the top or upper part of the outlet flow zone. The bottom or lower part of the inlet flow zone is connected to the bottom or lower part of the outlet flow zone.

[0012] Preferably, the baffle extends downward from the top of the inner cavity of the gas collecting tank, and a gap is left between the bottom end of the baffle and the bottom of the gas collecting tank.

[0013] Preferably, the ratio of the length of the partition to the height of the gas collection tank is 0.4-0.6.

[0014] Preferably, the air inlet of the condenser is located at the lower part or bottom of the condenser, and the air outlet of the condenser is located at the upper part or top of the condenser.

[0015] Preferably, the first refrigeration device is provided with a first refrigeration medium containing space and an opening for introducing or discharging refrigeration medium into or out of the first refrigeration medium containing space, and the gas collection tank is located within the first refrigeration medium containing space;

[0016] And / or, the product gas cylinder is equipped with a third refrigeration device capable of condensing germane gas entering the product gas cylinder;

[0017] And / or, the second refrigeration device is provided with a second refrigeration medium containing space and an opening for introducing or discharging refrigeration medium into or out of the second refrigeration medium containing space, wherein the condenser is located within the second refrigeration medium containing space.

[0018] Preferably, the second freezing medium containment space of the second freezing device is configured to allow the condenser to be completely submerged in the freezing medium.

[0019] In some examples, the freezing medium in the first freezing device, the second freezing device, and the third freezing device is liquid nitrogen, respectively;

[0020] And / or, the first freezing device, the second freezing device and the third freezing device are each a cold trap.

[0021] Preferably, a filter is provided on the second air outlet pipeline;

[0022] And / or, the metal packing is a Raschig ring, a Pall ring, or a step ring;

[0023] And / or, the outlet of the vacuum pump is connected to the exhaust gas treatment system.

[0024] Preferably, a needle valve is provided on the crude gas delivery pipeline;

[0025] A needle valve is provided on the third outlet pipeline, or a needle valve is provided on the connecting pipeline between the outlet of the condenser and the vacuum pump.

[0026] The technical solution provided by this utility model has the following beneficial effects:

[0027] This invention relates to a germane gas collection system that enables more thorough condensation of germane in crude germane product gas. Simultaneously, the inlet flow rate of the crude germane product gas can be flexibly adjusted via a gas volume flow meter and valves on the crude gas delivery pipeline. Furthermore, the H2 discharge rate can be flexibly adjusted by observing the pressure gauge and regulating valves on the third outlet pipeline, thus reducing the amount of germane product loss caused by germane being carried away by H2 during discharge. Therefore, this germane gas collection system effectively reduces germane product loss. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of a germane gas collection system in one embodiment. Detailed Implementation

[0029] To facilitate understanding of this utility model, the following description will further illustrate it with reference to embodiments. It should be understood that the following embodiments are merely for better understanding of this utility model and do not imply that this utility model is limited to the following embodiments.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Directional terms such as "upper," "lower," "top," and "bottom," mentioned or possibly used in this specification, are defined relative to the constructions shown in the accompanying drawings; they are relative concepts and may therefore vary depending on their location and usage. The terms "inner" and "outer" refer to directions toward or away from the geometric center of a particular component, respectively. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Throughout this document, the connection may be a direct or indirect connection.

[0031] See Figure 1 This invention provides a germane gas collection system, which mainly includes a crude product gas delivery pipeline 116, an inert gas delivery pipeline 117, a gas collection tank 102, a condenser 104, a product gas cylinder 107, and a vacuum pump 111. The crude product gas delivery pipeline 116 is used to deliver the crude germane product gas prepared by the upstream reaction, which mainly consists of germane and hydrogen. The inert gas delivery pipeline 117 is used to deliver inert gases, such as nitrogen, argon, or helium. The product gas cylinder 107 is used to collect and contain the germane product gas.

[0032] The crude gas delivery pipeline 116 and the inert gas delivery pipeline 117 are respectively connected to the inlet of the gas collection tank 102. A valve 1, preferably a needle valve, is installed on the crude gas delivery pipeline 116; a valve 2 is installed on the inert gas delivery pipeline 117. A gas volume flow meter 101 is installed on the crude gas delivery pipeline 116 to monitor the flow rate of the germane crude product gas entering the gas collection tank 102 from the crude gas delivery pipeline 116. The gas collection tank 102 is equipped with a first refrigeration device 103, which condenses the germane gas entering the gas collection tank 102, thereby separating germane and hydrogen in the germane crude product gas. The gas collection tank 102 is equipped with a pressure gauge 7.

[0033] The outlet of the gas collection tank 102 is connected to the inlet of the condenser tank 104 via a first outlet pipeline 118. The condenser tank 104 is filled with metal packing material 105. The outlet of the condenser tank 104 is connected to the inlet of the product gas cylinder 107 via a second outlet pipeline 120. The outlet of the condenser tank 104 is also connected to the vacuum pump 111 via a third outlet pipeline 119. The condenser tank 104 is equipped with a second refrigeration device 106, which can condense the germane gas entering the condenser tank 104.

[0034] Valves are respectively installed on the first vent line 118, the second vent line 120, and the third vent line 119, specifically, as follows: Figure 1 As shown, valves 3, 4, 5, and 6 are provided.

[0035] When germanane crude product gas is introduced into the gas collection tank 102 through the crude product gas delivery pipeline 116, the gas flow rate can be monitored by the gas volume flow meter 101. The flow rate of germanane crude product gas entering the gas collection tank 102 can be flexibly adjusted by adjusting the opening of valve 1. At the same time, by observing the pressure gauge 7 and adjusting the opening of valve 4, the H2 discharge rate can be flexibly adjusted, which helps to control the H2 discharge rate within the required range and reduces the amount of germanane product loss caused by germanane being carried away by H2 during H2 discharge. The system of this invention can improve the germanane gas collection efficiency, make germanane more thoroughly condensed and collected, and greatly reduce the loss of germanane product.

[0036] In some examples, such as Figure 1 As shown, the inert gas delivery line 117 and the crude gas delivery line 116 are connected. The gas volume flow meter 101 can also be used to monitor the gas flow rate output through the inert gas delivery line 117.

[0037] Specifically, the outlet of the vacuum pump 111 is connected to the exhaust gas treatment system 115, which delivers the exhaust gas to the exhaust gas treatment system 115 for treatment.

[0038] Preferably, such as Figure 1 As shown, the gas collection tank 102 is provided with a partition 114, which is specifically located in the inner cavity of the gas collection tank 102. The partition 114 divides the inner cavity of the gas collection tank 102 into an inlet flow zone 112 and an outlet flow zone 113. The inlet of the gas collection tank 102 is located at the top or upper part of the inlet flow zone 112, and the outlet of the gas collection tank 102 is located at the top or upper part of the outlet flow zone 113. The bottom or lower part of the inlet flow zone 112 is connected to the bottom or lower part of the outlet flow zone 113. When the crude germane product gas is introduced into the gas collection tank 102, it first enters the inner cavity of the gas collection tank 102 from the top and upper part of the inlet flow zone 112, then flows into the bottom or lower part of the inlet flow zone 112, then into the bottom or lower part of the outlet flow zone 113, and then flows to the top or upper part of the outlet flow zone 113. This allows the germane in the crude germane product gas to be condensed more thoroughly in the gas collection tank 102 and separated from hydrogen more fully.

[0039] Some better examples, such as Figure 1As shown, the baffle 114 extends downward from the top of the inner cavity of the gas collecting tank 102, with a gap between the bottom end of the baffle 114 and the bottom of the gas collecting tank 102. The baffle 114 divides the inner cavity of the gas collecting tank 102 into an inlet flow zone 112 and an outlet flow zone 113. Preferably, the ratio of the length of the baffle 114 to the height of the gas collecting tank 102 is 0.4-0.6.

[0040] Preferably, the air inlet of the condenser 104 is located at the lower part or bottom of the condenser 104, and the air outlet of the condenser 104 is located at the upper part or top of the condenser 104. This allows the gas to flow from bottom to top through the metal packing 105 filled inside the condenser 104, so that any germane gas that may remain in the gas and has not been condensed in the gas collection tank 102 can be condensed more fully, and the germane separation is more thorough.

[0041] Specifically, the first refrigeration device 103 is provided with a first refrigeration medium containing space 121, and also with an opening for introducing or discharging refrigeration medium 109 into the first refrigeration medium containing space 121. A gas collection tank 102 is located inside the first refrigeration medium containing space 121. After the refrigeration medium is introduced into the first refrigeration medium containing space 121, the germane gas entering the gas collection tank 102 can be condensed; and after the refrigeration medium is discharged from the first refrigeration medium containing space 121, the condensed germane can be re-vaporized.

[0042] Specifically, the product gas cylinder 107 is equipped with a third refrigeration device 108 capable of condensing germane gas entering the product gas cylinder 107. Specifically, the third refrigeration device is provided with a third refrigeration medium containing space 123, which has an opening for introducing or discharging refrigeration medium 109 into the third refrigeration medium containing space 123.

[0043] Specifically, the second refrigeration device 106 is provided with a second refrigeration medium containing space 122, and also with an opening for introducing or discharging the refrigeration medium 109 into the second refrigeration medium containing space 122. The condenser tank 104 is located within the second refrigeration medium containing space 122. When the refrigeration medium is introduced into the second refrigeration medium containing space 122, the germane gas entering the condenser tank 104 can be condensed; and when the refrigeration medium is discharged from the second refrigeration medium containing space 122, the condensed germane can be re-vaporized. Preferably, the second refrigeration medium containing space 122 of the second refrigeration device 106 is configured such that the condenser tank 104 is completely submerged in the refrigeration medium, such as... Figure 1 As shown, the condenser 104 is entirely located within the second refrigeration medium containing space 122 of the second refrigeration unit 106. When refrigeration medium is introduced into the second refrigeration medium containing space 122, the refrigeration medium can completely submerge the condenser 104, allowing the condenser 104 to more fully condense the residual germane gas and reduce the loss of germane product gas.

[0044] Preferably, the freezing medium 109 in the first freezing device 103, the second freezing device 106, and the third freezing device 108 is liquid nitrogen. In some examples, the first freezing device 103, the second freezing device 106, and the third freezing device 108 are cold traps.

[0045] Preferably, a filter 110 is provided on the second gas outlet line 120 to prevent solid particles that may be entrained in the gas from entering the product gas cylinder 107.

[0046] In some specific examples, the metal packing 105 is a Raschig ring, Pall ring, or step ring. By filling the condenser 104 with metal packing 105, the condensation surface area can be increased, allowing the germane product gas to be condensed more thoroughly and reducing germane product gas loss.

[0047] Preferably, a needle valve 1 is provided on the crude gas delivery line 116; a needle valve 4 is provided on the third gas outlet line 119; or a needle valve is provided on the connecting line between the gas outlet of the condenser 104 and the vacuum pump 111. Other valves can be ball valves.

[0048] To facilitate understanding of the technical solution of this utility model, the working process of the germane gas collection system of this utility model is illustrated below:

[0049] Example 1

[0050] In this embodiment, the crude germane product gas is prepared using a conventional method in the art of reducing germanium dioxide with borohydride. A schematic diagram of the germane gas collection system used is provided below. Figure 1 The description of the germane gas collection system is given above and will not be repeated here. In this embodiment, the ratio of the length of the baffle 114 inside the gas collection tank 102 to the height of the gas collection tank 102 is 0.6, the volume of the gas collection tank 102 is 30L, the inert gas is argon, and the metal packing 105 is Raschig rings.

[0051] S1, Gas displacement

[0052] Open valves 3, 4, and 5, start vacuum pump 111, and slowly open valve 6 to evacuate the gas collection tank 102, condenser 104, product gas cylinder 107, and all pipelines to below 4 PaA. Close valve 6, open valve 2, and introduce argon gas into the gas collection tank 102, condenser 104, and product gas cylinder 107 until atmospheric pressure is reached. Open valve 6 again and evacuate to below 4 PaA. Repeat this operation 4 times until the pressure inside these devices reaches 0 PaA, then close all valves.

[0053] S2, Collection of crude germane products

[0054] a. Add liquid nitrogen to the first freezing medium containing space 121 of the first freezing device 103 and the second freezing medium containing space 122 of the second freezing device 106 respectively, and immerse the entire condenser tank 104 in liquid nitrogen.

[0055] b. Slowly open valve 1, and control the flow rate of the germane crude product gas to 5L / min by observing the reading of the gas volume flow meter 101. The total volume of the germane crude product gas entering the gas collection tank 102 is 24L. Close valve 1 and observe the reading of pressure gauge 7. When the reading of pressure gauge 7 remains unchanged, the germane crude product gas is frozen by liquid nitrogen.

[0056] c. Open valves 3 and 6, and slowly open valve 4. By observing the reading of pressure gauge 7, control the average discharge rate of H2 in gas collection tank 102 to 5 kPa / min until the reading of pressure gauge 7 is 0 PaA. Then close valves 3, 4 and 6.

[0057] d. Repeat steps b and c until all the crude germane product gas produced by the reaction is collected.

[0058] S3, germane product gas transfer

[0059] Liquid nitrogen is added to the third refrigeration unit 108 to discharge the liquid nitrogen in the first refrigeration unit 103 and the second refrigeration unit 106. After the gas collection tank 102 and the condenser tank 104 return to room temperature, valves 3, 4 and 5 are opened, and the inlet valve of the product gas cylinder 107 is slowly opened to transfer the germane product gas in the gas collection tank 102 and the condenser tank 104 to the product gas cylinder 107.

[0060] Example 2

[0061] In this embodiment, the crude germane product gas is prepared using a conventional method in the art of reducing germanium dioxide with borohydride. A schematic diagram of the germane gas collection system used is provided below. Figure 1 The description of the germane gas collection system is given above and will not be repeated here. In this embodiment, the ratio of the length of the baffle 114 inside the gas collection tank 102 to the height of the gas collection tank 102 is 0.5, the volume of the gas collection tank 102 is 35L, the inert gas is nitrogen, and the metal packing 105 is Raschig rings.

[0062] S1, Gas displacement

[0063] Open valves 3, 4, and 5, start vacuum pump 111, and slowly open valve 6 to evacuate the gas collection tank 102, condenser 104, product gas cylinder 107, and all pipelines to below 4 PaA. Close valve 6, open valve 2, and introduce nitrogen into the gas collection tank 102, condenser 104, and product gas cylinder 107 until atmospheric pressure is reached. Open valve 6 again to evacuate to below 4 PaA. Repeat this operation 4 times until the pressure in these devices reaches 0 PaA, then close all valves.

[0064] S2, Collection of crude germane products

[0065] a. Liquid nitrogen is added to the first freezing medium containing space 121 of the first freezing device 103 and the second freezing medium containing space 122 of the second freezing device 106, respectively, so that the liquid nitrogen immerses the entire condenser tank 104.

[0066] b. Slowly open valve 1, and control the flow rate of the germane crude product to 6L / min by observing the reading of the gas volume flow meter 101. The total volume of the germane crude product gas entering the gas collection tank 102 is 30L. Close valve 1 and observe the reading of pressure gauge 7. When the reading of pressure gauge 7 remains unchanged, the germane crude product gas is frozen by liquid nitrogen.

[0067] c. Open valves 3 and 6, and slowly open valve 4. By observing the reading of pressure gauge 7, control the average discharge rate of H2 in gas collection tank 102 to 8 kPa / min until the reading of pressure gauge 7 is 0 PaA. Then close valves 3, 4 and 6.

[0068] d. Repeat steps b and c until all the crude germane product gas produced by the reaction is collected.

[0069] S3, germane product gas transfer

[0070] Liquid nitrogen is added to the third refrigeration unit 108 to discharge the liquid nitrogen in the first refrigeration unit 103 and the second refrigeration unit 106. After the gas collection tank 102 and the condenser tank 104 return to room temperature, valves 3, 4 and 5 are opened, and the inlet valve of the product gas cylinder 107 is slowly opened to transfer the germane product gas in the gas collection tank 102 and the condenser tank 104 to the product gas cylinder 107.

[0071] The above embodiments 1 and 2 are provided as specific application examples to illustrate this utility model. In specific applications, preferably, in step b of step S2, the volume of germane crude product gas entering the gas collection tank 102 each time is 0.6-1.2 times the volume of the gas collection tank 102; the flow rate of the germane crude product gas entering the gas collection tank 102 is 0.1-0.4V / min of the volume V of the gas collection tank 102; and the average discharge velocity of hydrogen in the gas collection tank 102 is 5-10 kPa / min, which helps to more effectively reduce the entrainment of germane product gas during hydrogen discharge.

[0072] It is readily understood that the above embodiments are merely illustrative examples for clear explanation and do not imply that the present invention is limited thereto. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A germane gas collection system characterized by, The system comprises a crude gas conveying pipeline for conveying the crude germane product gas, an inert gas conveying pipeline, a gas collecting tank, a condensing tank, a product gas cylinder and a vacuum pump; The crude gas conveying pipeline and the inert gas conveying pipeline are respectively communicated with the gas inlet of the gas collecting tank; the crude gas conveying pipeline is provided with a gas volume flow meter; the gas collecting tank is provided with a first refrigerating device capable of condensing the germane gas entering the gas collecting tank; the gas collecting tank is provided with a pressure gauge; The gas outlet of the gas collecting tank is communicated with the gas inlet of the condensing tank through a first gas outlet pipeline, the condensing tank is filled with metal packing, the gas outlet of the condensing tank is communicated with the gas inlet of the product gas cylinder through a second gas outlet pipeline, and the gas outlet of the condensing tank is also communicated with the vacuum pump through a third gas outlet pipeline; the condensing tank is provided with a second refrigerating device capable of condensing the germane gas entering the condensing tank; Valves are respectively arranged on the pipelines.

2. The germane gas collection system of claim 1, wherein, The inner cavity of the gas collecting tank is provided with a partition plate, the partition plate divides the inner cavity of the gas collecting tank into a gas inlet flow area and a gas outlet flow area, the gas inlet of the gas collecting tank is arranged at the top or upper part of the gas inlet flow area, the gas outlet of the gas collecting tank is arranged at the top or upper part of the gas outlet flow area, and the bottom or lower part of the gas inlet flow area is communicated with the bottom or lower part of the gas outlet flow area.

3. The germane gas collection system of claim 2, wherein, The partition plate extends downward from the top of the inner cavity of the gas collecting tank, and a gap is left between the bottom end of the partition plate and the bottom of the gas collecting tank.

4. The germane gas collection system of claim 3, wherein, The ratio of the length of the partition plate to the height of the gas collecting tank is 0.4-0.

6.

5. The germane gas collection system according to any one of claims 1 to 4, wherein The gas inlet of the condensing tank is located at the lower part or bottom of the condensing tank, and the gas outlet of the condensing tank is located at the upper part or top of the condensing tank.

6. The germane gas collection system according to any one of claims 1 to 4, wherein The first refrigerating device is provided with a first refrigerating medium containing space, and is also provided with an opening for introducing or discharging refrigerating medium into the first refrigerating medium containing space, and the gas collecting tank is located in the first refrigerating medium containing space; And / or, the product gas cylinder is provided with a third refrigerating device capable of condensing the germane gas entering the product gas cylinder; And / or, the second refrigerating device is provided with a second refrigerating medium containing space, and is also provided with an opening for introducing or discharging refrigerating medium into the second refrigerating medium containing space, and the condensing tank is located in the second refrigerating medium containing space.

7. The germane gas collection system of claim 6, wherein, The second refrigerating medium containing space of the second refrigerating device is configured to enable the condensing tank to be completely immersed in refrigerating medium.

8. The germane gas collection system of claim 6, wherein, The refrigerating medium in the first refrigerating device, the second refrigerating device and the third refrigerating device is liquid nitrogen respectively; And / or, the first refrigerating device, the second refrigerating device and the third refrigerating device are cold traps respectively.

9. The germane gas collection system according to any one of claims 1 to 4, wherein A filter is arranged on the second gas outlet pipeline; And / or, the metal packing is Rasai ring, Paul ring or ladder ring; And / or, the gas outlet of the vacuum pump is connected with a tail gas treatment system.

10. The germane gas collection system according to any one of claims 1 to 4, wherein A needle valve is arranged on the crude gas conveying pipeline; A needle valve is arranged on the third gas outlet pipeline, or a needle valve is arranged on the connecting pipeline between the gas outlet of the condensing tank and the vacuum pump.

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