Load lock cavity vacuumizing method

Abstract

The invention discloses a load lock cavity vacuumizing method, and relates to the technical field of semiconductor manufacturing, and the method comprises the steps: before a load lock cavity body prepares to open a stop valve, a time relay is started, and a normally closed air valve is triggered; in the primary extraction process, the normally closed gas valve is opened, so that gas enters the primary extraction gas valve through the first auxiliary gas pipeline; the primary extraction valve introduces gas into the load lock cavity body, primary vacuumizing treatment is carried out, and airflow flowing in the load lock cavity body is reduced. Through the sequential control of the initial extraction valve and the normally closed valve, the load lock cavity is primarily vacuumized before the stop valve is opened, the pressure difference between the cavity and a preceding-stage vacuum pipeline is reduced, the airflow flowing in the cavity when the stop valve is opened is reduced, the cavity environment is relatively stable, and particles in the cavity cannot contaminate a wafer along with the airflow flowing. Therefore, particles on the wafer are reduced, the problem that the concentration of the particles on the wafer is too high after the load lock cavity is vacuumized is solved, and the concentration of the particles on the wafer can be reduced after the load lock cavity is vacuumized.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing technology, and in particular to a load lock chamber vacuum pumping method. Background Art

[0002] In the semiconductor manufacturing process, the Loadlock chamber is a key component. It is located between the clean environment and the process chamber and is used to transfer wafers from the external environment to the process chamber. The main functions of the Loadlock chamber include: preventing external contaminants from entering the process chamber and ensuring the stability of the vacuum and gas composition in the process chamber.

[0003] In traditional semiconductor manufacturing equipment, vacuum is directly performed after the stop valve is opened. The traditional vacuum method may cause drastic changes in the air pressure in the cavity in a short period of time, affecting the stability of the vacuum degree, thereby having an adverse effect on the process and causing the particles in the cavity to be unable to be completely removed. These particles will adhere to the wafer surface during the transmission process, affecting the stability of subsequent processes and the yield of the product.

[0004] Therefore, a load lock chamber vacuum pumping method is needed to solve the problem of excessively high particle concentration on the wafer after the load lock chamber is vacuum pumped, so as to reduce the particle concentration on the wafer in the chamber after the load lock chamber is vacuum pumped. Summary of the invention

[0005] The purpose of the present application is to solve the problem of excessively high particle concentration on the wafer after the load lock chamber is evacuated. In order to solve the above problem, the present application provides a load lock chamber evacuation method, which can reduce the particle concentration on the wafer after the load lock chamber is evacuated.

[0006] To achieve the above-mentioned purpose, the embodiment of the present application adopts the following technical solutions: S100: connect one end of the first auxiliary gas pipeline to the gas source, and the other end to the input end of the normally closed gas valve; S200: connect the output end of the normally closed gas valve to the initial gas pumping valve through the second auxiliary gas pipeline; S300: connect the time relay to the solenoid valve signal interface of the pneumatic controller; S400: before the load lock chamber is ready to open the stop valve, the time relay is started to trigger the normally closed gas valve; S500: during the initial pumping process, the normally closed gas valve is opened to allow gas to enter the initial gas pumping valve through the first auxiliary gas pipeline; S600: the initial gas pumping valve introduces gas into the load lock chamber for preliminary vacuum pumping to reduce the air flow in the load lock chamber; S700: after the initial pumping is completed, the time relay closes the initial gas pumping valve, and the normally closed gas valve also returns to the closed state. At this time, the stop valve of the load lock chamber is opened for normal vacuum pumping operation.

[0007] In the above technical scheme, the embodiment of the present application realizes preliminary vacuuming of the load lock chamber before opening the stop valve by setting the sequential control of the initial vacuum valve and the normally closed air valve, thereby reducing the air flow in the load lock chamber, solving the problem of excessively high particle concentration on the wafer after the load lock chamber is vacuumed, and reducing the particle concentration on the wafer after the load lock chamber is vacuumed.

[0008] Further, according to an embodiment of the present application, the first auxiliary gas pipeline is a 1 / 4 inch gas pipeline, and the second auxiliary gas pipeline is a 1 / 4 inch gas pipeline.

[0009] Further, according to an embodiment of the present application, the time relay is set to perform an initial pumping for 15-20 seconds before opening the stop valve.

[0010] Further, according to an embodiment of the present application, the diameter of the main gas pipeline is larger than that of the first auxiliary gas pipeline and the second auxiliary gas pipeline.

[0011] Further, according to an embodiment of the present application, the normally closed valve remains closed when not powered.

[0012] Further, according to an embodiment of the present application, the solenoid valve signal interface of the pneumatic controller is connected to the time relay through a signal line.

[0013] Further, according to an embodiment of the present application, an input end of the pneumatic controller solenoid valve is connected to the first auxiliary gas pipeline.

[0014] Further, according to an embodiment of the present application, the air source at the input end is provided by a pneumatic controller.

[0015] Further, according to an embodiment of the present application, both the normally closed air valve and the initial air extraction valve are equipped with pressure sensors.

[0016] Further, according to an embodiment of the present application, the normally closed valve remains closed when not powered.

[0017] Compared with the prior art, the present application has the following beneficial effects: the present application realizes preliminary vacuuming of the load lock chamber before opening the stop valve by setting the sequence control of the initial vacuum valve and the normally closed air valve, so as to reduce the air flow in the load lock chamber, solve the problem of excessively high particle concentration on the wafer after the load lock chamber is vacuumed, and can reduce the particle concentration on the wafer after the load lock chamber is vacuumed. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present application is further described below in conjunction with the accompanying drawings and embodiments.

[0019] Figure 1 A flow chart of a method for evacuating a load lock chamber.

[0020] Figure 2 It is an axonometric view of the primary air extraction valve.

[0021] Figure 3 This is the front view of the initial air extraction valve.

[0022] Figure 4 It is a top view of the initial exhaust valve.

[0023] Figure 5 After improvement Figure 4 "AA" section view of the.

[0024] In the attached figure

[0025] 1. Initial gas extraction valve 11, main gas pipeline 21, first auxiliary gas pipeline

[0026] 22. Second auxiliary gas pipeline 23. Quick release device 231. Pressure sensing block

[0027] 232, movable pin 233, spring 234, fixed block

[0028] 2341, positioning part 2342, fixing part 3, normally closed air valve

[0029] 41. Time relay 42. Pneumatic controller solenoid valve DETAILED DESCRIPTION

[0030] In order to make the purpose and technical solution of the present invention clearly and completely described, and the advantages more clearly understood, the embodiments of the present invention are further described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are part of the embodiments of the present invention, rather than all of the embodiments, and are only used to explain the embodiments of the present invention, and are not used to limit the embodiments of the present invention. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that the terms "center", "middle", "upper", "lower", "left", "right", "inner", "outer", "top", "bottom", "side", "vertical", "horizontal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "one", "first", "second", "third", "fourth", "fifth", "sixth" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] For the purpose of simplicity and illustration, the principles of the embodiments are described primarily by reference to examples. In the following description, many specific details are presented to provide a thorough understanding of the embodiments. However, it is apparent that, for those of ordinary skill in the art, these embodiments may not be limited to these specific details in practice. In some instances, known methods and apparatus are not described in detail to avoid making these embodiments unnecessarily difficult to understand. In addition, all embodiments may be used in combination with each other.

[0034] Embodiment 1: Figure 1-2 As shown, a load lock chamber vacuum pumping method includes:

[0035] S100: Connect one end of the first auxiliary gas pipeline 21 to the gas source, and the other end to the input end of the normally closed gas valve 3. The first auxiliary gas pipeline 21 is a 1 / 4 inch gas pipeline. The use of a 1 / 4 inch gas pipeline ensures a stable gas flow and provides sufficient gas supply to support the initial extraction process.

[0036] S200: Connect the output end of the normally closed gas valve 3 to the primary gas extraction valve 1 through the second auxiliary gas pipeline 22. The second auxiliary gas pipeline 22 is a 1 / 4 inch gas pipeline. Using a smaller diameter 1 / 4 inch gas pipeline can effectively control the gas flow rate and ensure that the gas can accurately enter the primary gas extraction valve 1.

[0037] S300: Connect the time relay 41 to the signal interface of the pneumatic controller solenoid valve 42. The connection of the time relay 41 enables the system to automatically control the opening and closing of the initial air extraction valve 1 within the set time, thereby realizing automatic control of the initial extraction.

[0038] S400: When the load lock chamber is ready to open the stop valve, the time relay 41 is started to trigger the normally closed gas valve 3. In the initial pumping stage, the time relay 41 is triggered to ensure that the initial pumping valve 1 is opened in time, so that the initial pumping process can proceed smoothly.

[0039] S500: During the initial vacuuming process, the normally closed gas valve 3 is opened to allow the gas to enter the initial vacuuming valve 1 through the first auxiliary gas pipeline 21. Through the control of the normally closed gas valve 3, it is ensured that the gas smoothly enters the initial vacuuming valve 1 to achieve the initial vacuuming operation.

[0040] S600: The initial vacuum valve 1 introduces gas into the load lock chamber to perform a preliminary vacuum process to reduce the air flow in the load lock chamber;

[0041] S700: After the initial pumping is completed, the time relay 41 closes the initial pumping valve 1, and the normally closed gas valve 3 also returns to the closed state. At this time, the stop valve of the load lock chamber is opened, and the main gas pipeline 11 works to perform normal vacuum pumping operations. After the initial pumping is completed, the system's airtightness is ensured by closing the initial pumping valve 1 and the normally closed gas valve 3, and then the stop valve is opened for normal vacuum pumping operations to ensure that the vacuum degree of the load lock chamber meets the process requirements.

[0042] The time relay 41 is set to perform an initial pumping of 15-20 seconds before opening the stop valve. The normally closed gas valve 3 remains closed when not powered. The time relay 41 is provided with an adjustable function to adjust the initial pumping time according to different load lock chamber requirements.

[0043] The signal interface of the pneumatic controller solenoid valve 42 is connected to the time relay 41 through a signal line. The input end of the pneumatic controller solenoid valve 42 is connected to the first auxiliary gas pipeline 21, and the input end gas source is provided by the pneumatic controller.

[0044] The normally closed air valve 3 and the initial air extraction valve 1 are both equipped with pressure sensors, and the normally closed air valve 3 remains in a closed state when not powered.

[0045] Embodiment 2: Figure 2-4 As shown, based on the first embodiment, this embodiment further improves the first auxiliary gas pipeline 21 and the second auxiliary gas pipeline 22, including:

[0046] The same quick-release devices 23 are respectively provided at both ends of the first auxiliary gas pipeline 21 and the second auxiliary gas pipeline 22;

[0047] The quick-release device 23 includes: a pressure-sensitive block 231, which is arranged at one end of the first auxiliary gas pipeline 21. The pressure-sensitive block 231 and one end of the first auxiliary gas pipeline 21 are connected by a movable pin 232, and the other end is connected by a spring 233. The spring 233 supports the pressure-sensitive block 231 to be inclined to the first auxiliary gas pipeline 21.

[0048] A fixed block 234, the fixed block 234 is arranged at one end of the pressure sensing block 231, the fixed block 234 is fixedly connected to the initial exhaust valve 1, and the fixed block 234 includes: a positioning part 2341, the positioning part 2341 is arranged at the lower end of the fixed block 234, the outer diameter of the positioning part 2341 is smaller than the inner diameter of the first auxiliary gas pipeline 21 and is arranged tangently, which is used to quickly position the first auxiliary gas pipeline 21 when it is connected to prevent deviation and gas leakage; a fixed part 2342, the left end face of the fixed part 2342 is arranged parallel to the right end face of the first auxiliary gas pipeline 21, and there is a gap between the inner surface of the fixed part 2342 and the outer surface of the first auxiliary gas pipeline 21, so that the pressure sensing block 231 can extend into the interior of the fixed block 234; an opening is arranged at the upper end of the fixed part 2342, the size of the opening is the same as the size of the upper end face of the pressure sensing block 231, and the connection method between the second auxiliary gas pipeline 22 and the quick-release device 23 is the same as that of the first auxiliary gas pipeline 21.

[0049] When the first auxiliary gas pipeline 21 or the second auxiliary gas pipeline 22 needs to be connected, the first auxiliary gas pipeline 21 or the second auxiliary gas pipeline 22 is initially positioned through the positioning portion 2341 to prevent deviation, and the upper end surface of the pressure sensing block 231 is pressed to compress the pressure sensing block 231 by a certain distance so that the pressure sensing block 231 can enter the fixed block through the gap between the inner surface of the fixing portion 2342 and the outer surface of the first auxiliary gas pipeline 21. When the upper end surface of the pressure sensing block 231 passes through the upper opening of the fixing portion 2342, the spring 233 bounces the pressure sensing block 231 upward into the opening. Fix the position of the first auxiliary gas pipeline 21 or the second auxiliary gas pipeline 22. At this time, the left end surface of the fixing part 2342 and the upper surface of the positioning part 2341 are completely in contact with the right end surface and the lower surface of the first auxiliary gas pipeline 21 or the second auxiliary gas pipeline 22 respectively to prevent gas leakage. When the first auxiliary gas pipeline 21 or the second auxiliary gas pipeline 22 needs to be replaced, press the pressure sensing block 231 again, pull out the first auxiliary gas pipeline 21 and the second auxiliary gas pipeline 22, and complete the quick loading and unloading. It is suitable for occasions where frequent replacement of gas pipes is required, and air tightness is guaranteed. Example 3: If the first auxiliary gas pipeline 21 or the second auxiliary gas pipeline 22 needs to be replaced, press the pressure sensing block 231 again, pull out the first auxiliary gas pipeline 21 and the second auxiliary gas pipeline 22, and complete the quick loading and unloading. Figure 1-5 As shown, based on Embodiment 1-2, this embodiment further provides a load lock chamber vacuum pumping method, comprising:

[0050] One end of the first auxiliary gas pipeline 21 (1 / 4 inch) is connected to the gas source, and the other end is connected to the input end of the normally closed gas valve 3 .

[0051] The first auxiliary gas pipeline 21 and the second auxiliary gas pipeline 22 are preliminarily positioned by the positioning portion 2341 to prevent deviation.

[0052] The upper end surface of the pressure sensing block 231 is pressed to compress the pressure sensing block 231 and make it enter the interior of the fixing block 234. When the upper end surface of the pressure sensing block 231 passes through the upper opening of the fixing portion 2342, the spring 233 bounces the pressure sensing block 231 into the opening to fix the position of the gas pipeline.

[0053] The time relay 41 is connected to the signal interface of the pneumatic controller solenoid valve 42.

[0054] When the load lock chamber is ready to open the stop valve, the time relay 41 is started to trigger the normally closed gas valve 3.

[0055] During the initial extraction process, the normally closed gas valve 3 is opened to allow gas to enter the initial extraction valve 1 through the first auxiliary gas pipeline 21 and the second auxiliary gas pipeline 22 .

[0056] The initial vacuum valve 1 introduces gas into the load lock chamber to perform a preliminary vacuum process to reduce the gas flow in the load lock chamber.

[0057] After the initial vacuuming is completed, the time relay 41 closes the initial vacuuming valve 1, and the normally closed valve 3 also returns to the closed state. At this time, the stop valve of the load lock chamber is opened, the main gas pipeline 11 works, and normal vacuuming operation is performed.

[0058] When the first auxiliary gas pipeline 21 and the second auxiliary gas pipeline 22 need to be replaced, the pressure sensing block 231 is pressed to pull the gas pipelines outwards, thereby completing quick installation and removal.

[0059] By setting the sequence control of the initial exhaust valve 1 and the normally closed valve 3, the load lock chamber is initially evacuated before the stop valve is opened to reduce the air flow in the load lock chamber, solve the problem of excessively high particle concentration on the wafer after the load lock chamber is evacuated, and reduce the particle concentration on the wafer after the load lock chamber is evacuated.

[0060] Although the above describes the illustrative specific implementation methods of the present application so that technicians in this technical field can understand the present application, the present application is not limited to the scope of the specific implementation methods. For ordinary technicians in this technical field, as long as various changes are within the spirit and scope of the present application defined and determined by the attached claims, all application creations using the concept of the present application are protected.

Claims

1. A method for evacuating a load lock chamber, characterized in that: include: S100: Connect one end of the first auxiliary gas pipeline to the gas source, and the other end to the input end of the normally closed gas valve; S200: connecting the output end of the normally closed gas valve to the primary gas extraction valve through a second auxiliary gas pipeline; S300: Connect the time relay to the solenoid valve signal interface of the pneumatic controller; S400: When the load lock chamber is ready to open the stop valve, the time relay is started to trigger the normally closed gas valve; S500: the normally closed gas valve is opened to allow gas to enter the primary gas extraction valve through the first auxiliary gas pipeline and the second auxiliary gas pipeline; S600: the initial vacuum valve introduces gas into the load lock chamber to perform a preliminary vacuum process to reduce the air flow in the load lock chamber; S700: After the initial vacuuming is completed, the time relay closes the initial vacuuming valve, and the normally closed valve also returns to the closed state. At this time, the stop valve of the load lock chamber is opened, the main gas pipeline works, and normal vacuuming operation is performed.

2. A load lock chamber vacuum pumping method according to claim 1, characterized in that: The first auxiliary gas pipeline is a 1 / 4 inch gas pipeline, and the second auxiliary gas pipeline is a 1 / 4 inch gas pipeline.

3. A load lock chamber vacuum pumping method according to claim 1, characterized in that: The time relay is set to perform an initial pumping of 15-20 seconds before opening the stop valve.

4. A load lock chamber vacuum pumping method according to claim 1, characterized in that: The main gas pipeline has a larger diameter than the first auxiliary gas pipeline and the second auxiliary gas pipeline.

5. A load lock chamber vacuum pumping method according to claim 1, characterized in that: The normally closed gas valve remains in a closed state when not powered.

6. A load lock chamber vacuum pumping method according to claim 1, characterized in that: The pneumatic controller solenoid valve signal interface is connected to the time relay via a signal line.

7. A load lock chamber vacuum pumping method according to claim 6, characterized in that: An input end of the pneumatic controller solenoid valve is connected to the first auxiliary gas pipeline.

8. A load lock chamber vacuum pumping method according to claim 1, characterized in that: The air source at the input end is provided by the pneumatic controller.

9. A load lock chamber vacuum pumping method according to claim 1, characterized in that: The normally closed air valve and the initial air extraction valve are both equipped with pressure sensors.

10. A load lock chamber vacuum pumping method according to claim 1, characterized in that: The normally closed gas valve remains in a closed state when not powered.

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