Device for recycling doped gas
By using a closed condenser and jacket in the doped gas recovery device for condensing and separation, the problem of difficulty in recycling doped gas is solved, and cost savings and safety accidents are achieved.
Patent Information
- Application Number
- CN202420506510.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-15
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-03-15
AI Technical Summary
In the manufacturing of semiconductor devices and integrated circuits, the difficulty in recycling doped gas leads to high production costs and large loads in the exhaust gas treatment tower, and the risk of dangerous accidents such as leakage.
A device including a closed condenser and jacket is designed to exchange heat through refrigerant such as liquid nitrogen to condense and liquefy the exhaust gas to be processed, and gas separation and recovery are realized through valves and recovery branches to reduce exhaust gas treatment. Tower load.
Effectively separate and recover gases such as hydrogen, nitrogen, argon, etc. in the exhaust gas, reduce production costs, avoid toxic gases entering the exhaust gas treatment tower, and reduce leakage risks.
Smart Images
Figure CN222239470U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a device for recycling doped gas and relates to the field of chemical equipment. Background Art
[0002] In the manufacture of semiconductor devices and integrated circuits, some or certain impurities are doped into semiconductor materials to give the materials the required conductivity type and a certain resistivity, and to manufacture PN junctions, resistors, buried layers, etc. The gas doping source used in the doping process is called doping gas. It mainly includes arsine, phosphine, phosphorus trifluoride, boron trifluoride, boron trichloride, germanium tetrafluoride and diborane.
[0003] With the improvement of semiconductor technology, in order to improve doping efficiency and yield rate, a small amount of other gases, such as hydrogen, nitrogen, argon, helium, etc., are added during filling of doping gas. However, it is difficult to recover doping gas during filling or production process, which leads to high production cost on one hand and high processing load of tail gas treatment tower on the other hand, and there is a risk of dangerous accidents such as leakage. Utility Model Content
[0004] In view of the deficiencies in the prior art, the technical problem to be solved by the utility model is to provide a device for recycling doped gas.
[0005] In order to solve the above technical problems, the technical solution of the utility model is: a device for recycling doped gas, comprising a closed condenser, the outer surface of the condenser is provided with a jacket, the jacket is connected to a refrigerant inlet pipe and a refrigerant exhaust pipe, the condenser is connected to an exhaust gas inlet pipe and a non-condensable gas exhaust pipe, and the non-condensable gas exhaust pipe is connected to a recovery branch pipe returning to the filling line.
[0006] Preferably, a first valve is installed on the refrigerant inlet pipe, a second valve is installed on the refrigerant exhaust pipe, a third valve is installed on the tail gas inlet pipe, a fourth valve is installed on the non-condensable gas exhaust pipe, and a fifth valve is installed on the recovery branch pipe.
[0007] Preferably, the recovery branch pipe is connected to the non-condensable gas exhaust pipe between the condenser and the fourth valve.
[0008] Preferably, a pressure gauge is installed on the non-condensable gas exhaust pipe between the condenser and the fourth valve.
[0009] Preferably, a liquid level meter is also installed on the condenser.
[0010] Preferably, the jacket is fixed to the outer periphery and outer bottom of the condenser, and the refrigerant inlet pipe and the refrigerant exhaust pipe are connected to the interior of the jacket.
[0011] Compared with the prior art, the utility model has the following beneficial effects: the device for recycling doped gas includes a jacket for heat exchange, and the system temperature is lowered by introducing liquid nitrogen and other refrigerants into the jacket; the condenser is a reaction tank for condensing and liquefying the doped gas mixed gas tail gas to be treated, wherein the doped gas can be phosphine, arsine, boron trifluoride, germanium tetrafluoride, boron trichloride, etc., and the mixed gas can be hydrogen, nitrogen, argon, helium, etc. The utility model can separate hydrogen, nitrogen, argon, helium, etc. in the tail gas, effectively saving costs; the setting of the utility model can also reduce the processing load of the tail gas treatment tower, and avoid a large amount of toxic gases from entering the tail gas treatment tower at the same time, causing leakage and other dangerous accidents.
[0012] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a schematic diagram of the structure of an embodiment of the utility model. DETAILED DESCRIPTION
[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments.
[0015] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.
[0016] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.
[0017] like Figure 1 As shown, this embodiment provides a device for recycling doped gas, including a closed condenser 6, the outer surface of the condenser is provided with a jacket 7, the jacket is connected to a refrigerant inlet pipe 8 and a refrigerant exhaust pipe 9, the condenser is connected to an exhaust gas inlet pipe 10 and a non-condensable gas exhaust pipe 11, and the non-condensable gas exhaust pipe is connected to a recovery branch pipe 12 returning to the filling line.
[0018] The temperature of the system is lowered by introducing other refrigerants such as liquid nitrogen into the jacket; the condenser is a reaction tank for condensing and liquefying the mixed gas tail gas of the doped gas to be treated, wherein the doped gas can be phosphine, arsine, boron trifluoride, germanium tetrafluoride, boron trichloride, etc., and the mixed gas can be hydrogen, nitrogen, argon, helium, etc. The utility model can separate hydrogen, nitrogen, argon, helium, etc. in the tail gas, effectively saving costs and reducing the waste of doped gas during filling or production; the setting of the utility model can also reduce the processing load of the tail gas treatment tower, avoiding a large amount of toxic gas from entering the tail gas treatment tower at the same time, causing leakage and other dangerous accidents.
[0019] In the embodiment of the utility model, a first valve 1 is installed on the refrigerant inlet pipe, a second valve 2 is installed on the refrigerant exhaust pipe, a third valve 3 is installed on the exhaust gas inlet pipe, a fourth valve 4 is installed on the non-condensable gas exhaust pipe, and a fifth valve 5 is installed on the recovery branch pipe.
[0020] In an embodiment of the utility model, the recovery branch pipe is connected to the non-condensable gas exhaust pipe between the condenser and the fourth valve.
[0021] In the embodiment of the utility model, a pressure gauge 13 is installed on the non-condensable gas exhaust pipe between the condenser and the fourth valve.
[0022] In the embodiment of the utility model, a liquid level meter 14 is also installed on the condenser.
[0023] In an embodiment of the utility model, the jacket is fixed to the outer periphery and the outer bottom of the condenser, and the refrigerant inlet pipe and the refrigerant exhaust pipe are connected to the interior of the jacket.
[0024] In the embodiment of the utility model, the working principle of the device for recycling doping gas is:
[0025] 1. Liquid nitrogen is used as the refrigerant. The liquid nitrogen enters the jacket through the refrigerant inlet pipe and the first valve. After heat exchange in the jacket, it is discharged through the second valve and is used after being re-liquefied and cooled, thereby forming a cooling circuit;
[0026] 2. Open the third valve, and the phosphine containing impurities produced in the previous process is discharged into the condenser. At this time, the temperature inside the condenser has been cooled to about -150°C by liquid nitrogen. The boiling point of phosphine is -87°C, so the phosphine is liquefied at this time;
[0027] 3. The main impurities in phosphine are hydrogen, nitrogen, argon, helium, one or more of which are difficult to liquefy at -150°C. We call them non-condensable gases. At this time, the fourth valve remains in the start state, and the non-condensable gas is discharged into the tail gas treatment tower through the non-condensable gas exhaust pipe for harmless treatment before discharge;
[0028] 4. When the liquid level gauge of the condenser shows a high alarm or when you want to recover the phosphine in the condenser, close the first valve to prevent the liquid nitrogen from entering the jacket. To prevent the remaining liquid nitrogen in the jacket from causing pressure build-up due to temperature recovery, the second valve is open;
[0029] 5. At the same time, close the third valve, suspend feeding, allow the condenser to naturally return to temperature, close the fourth valve, and open the fifth valve. At this time, the liquid phosphine inside the condenser evaporates into gaseous state and returns to the filling line or the previous process through the fifth valve;
[0030] 6. After the phosphine inside the condenser is completely discharged, open the first valve first. When the temperature inside the condenser drops to about -150°C, close the fifth valve, and open the third and fourth valves. The phosphine tail gas can continue to be discharged into the condenser for condensation.
[0031] 7. Set a pressure gauge on the condenser. When the system is over-pressured, cut off the third valve for feed and start the fourth valve for tail gas treatment to release the pressure steadily to ensure that the pressure of the system is at a normal level.
[0032] The above is only the preferred embodiment of the utility model, and does not limit the utility model in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the utility model without departing from the technical solution of the utility model still belongs to the protection scope of the technical solution of the utility model.
Claims
1. A device for recycling doping gas, characterized in that: It comprises a closed condenser, the outer surface of which is provided with a jacket, the jacket is connected with a refrigerant inlet pipe and a refrigerant exhaust pipe, the condenser is connected with an exhaust gas inlet pipe and a non-condensable gas exhaust pipe, and the non-condensable gas exhaust pipe is connected with a recovery branch pipe of a return filling line.
2. The device for recycling doping gas according to claim 1, characterized in that: A first valve is installed on the refrigerant inlet pipe, a second valve is installed on the refrigerant exhaust pipe, a third valve is installed on the tail gas inlet pipe, a fourth valve is installed on the non-condensable gas exhaust pipe, and a fifth valve is installed on the recovery branch pipe.
3. The device for recycling doping gas according to claim 2, characterized in that: The recovery branch pipe is connected to the non-condensable gas exhaust pipe between the condenser and the fourth valve.
4. The device for recycling doping gas according to claim 2, characterized in that: A pressure gauge is installed on the non-condensable gas exhaust pipe between the condenser and the fourth valve.
5. The device for recycling doping gas according to claim 1, characterized in that: A liquid level gauge is also installed on the condenser.
6. The device for recycling doping gas according to claim 1, characterized in that: The jacket is fixed on the outer periphery and the outer bottom of the condenser, and the refrigerant inlet pipe and the refrigerant outlet pipe are connected to the interior of the jacket.