Vacuum adsorption system and semiconductor processing equipment

Abstract

The utility model discloses a vacuum adsorption system and semiconductor processing equipment, the vacuum adsorption system comprises a base located in a reaction cavity, the base is used for bearing and adsorbing a wafer, a backpressure pipeline is arranged in the base, one end of the backpressure pipeline provides negative pressure for the surface of the base so as to adsorb the wafer, and the other end of the backpressure pipeline provides negative pressure for the surface of the base. The other end of the backpressure pipeline is respectively communicated with an air exhaust pipeline and an air supply pipeline, the air exhaust pipeline is communicated with a vacuum pump, the vacuum pump exhausts air to provide negative pressure, and a pressure control unit is arranged on the air supply pipeline to adjust the air supply pressure flow; and an air extraction valve unit is arranged on the air extraction pipeline to control the air extraction pressure and flow. Through cooperation of the flow valve unit and the pressure control unit, stable adsorption pressure can be provided for a complex back pressure conversion process.

Description

Technical Field

[0001] The utility model relates to the field of semiconductors, in particular to a vacuum adsorption system and semiconductor processing equipment. Background Art

[0002] In the semiconductor manufacturing process, there are several ways to fix wafers: electrostatic adsorption, vacuum adsorption, etc. Among them, vacuum adsorption forms a negative pressure on the vacuum back pressure adsorption base to adsorb the wafer thereon.

[0003] The existing vacuum adsorption systems provide a very limited range of back pressure and are used in a relatively simple manner, and cannot meet the needs of complex processes such as high- and low-pressure switching. Summary of the invention

[0004] Based on the above problems, the utility model provides a vacuum adsorption system, which can provide a stable adsorption pressure for a complex back pressure conversion process through the cooperation of a flow valve unit and a pressure control unit.

[0005] In order to achieve the above-mentioned purpose, the utility model provides a vacuum adsorption system, including a base located in a reaction chamber, the base is used to support and adsorb wafers, a back-pressure pipeline is arranged in the base, one end of the back-pressure pipeline provides negative pressure to the surface of the base to adsorb wafers, and the other end of the back-pressure pipeline is respectively connected to an exhaust pipeline and an air supply pipeline, the exhaust pipeline is connected to a vacuum pump, and the vacuum pump exhausts air to provide negative pressure, and a pressure control unit is arranged on the air supply pipeline to adjust the air supply pressure flow; an exhaust valve unit is arranged on the exhaust pipeline to control the exhaust pressure flow.

[0006] Optionally, a back pressure valve is provided on the back pressure pipeline.

[0007] Optionally, the pressure control unit includes a mass flow control unit and a pressure sensor.

[0008] Optionally, the flow control unit is located upstream of the pressure sensor.

[0009] Optionally, the air extraction valve unit and the back pressure valve include a flow valve.

[0010] Optionally, the downstream of the pressure control unit is connected to the reaction chamber through a pressure relief pipeline, and the opening is controlled by a pressure relief valve.

[0011] Optionally, the air extraction valve unit is configured as a regulating valve group, and the regulating valve group includes a plurality of regulating valves connected in parallel.

[0012] Optionally, the flow coefficient of each regulating valve is different.

[0013] Optionally, the flow coefficients between the plurality of regulating valves differ by multiples.

[0014] The utility model also provides a semiconductor processing device, comprising the above-mentioned vacuum adsorption system.

[0015] The utility model can provide a stable adsorption pressure for a complex back pressure conversion process through the cooperation of a flow valve unit and a pressure control unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The utility model is a schematic diagram of a vacuum adsorption system.

[0017] Figure 2 This is another schematic diagram of a vacuum adsorption system of the present utility model.

[0018] Figure 3 The utility model is a schematic diagram of another vacuum adsorption system.

[0019] Figure 4 The utility model is a schematic diagram of a vacuum adsorption system.

[0020] Figure ID:

[0021] Wafer W

[0022] Base 10

[0023] Pressure control unit 20

[0024] Mass flow control unit 21

[0025] Pressure sensor 22

[0026] Back pressure line 30

[0027] Back pressure valve 31

[0028] Air extraction line 40

[0029] Air extraction valve unit 41

[0030] Regulating valve group 410

[0031] The first regulating valve 411

[0032] Second regulating valve 412

[0033] Nth regulating valve 41N

[0034] Vacuum pump 50

[0035] Pressure relief line 60

[0036] Pressure relief valve 61

[0037] Reaction chamber 100 DETAILED DESCRIPTION

[0038] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0039] According to one aspect of the utility model, a vacuum adsorption system is provided, such as Figure 1 As shown, it includes a susceptor 10 located in a reaction chamber 100, and the susceptor 10 is used to carry and adsorb wafers W. A back pressure pipeline 30 is provided in the susceptor 10, and one end of the back pressure pipeline 30 provides negative pressure to the surface of the susceptor 10 to adsorb wafers W. A back pressure valve 31 is provided on the back pressure pipeline 30 to adjust the back pressure. Preferably, the back pressure valve 31 includes a flow valve to provide precise back pressure control.

[0040] The other end of the back pressure pipeline 30 is connected to the exhaust pipeline 40 and the gas supply pipeline. The exhaust pipeline 40 is connected to the vacuum pump 50, and the vacuum pump 50 is used to exhaust gas to provide negative pressure. A pressure control unit 20 is provided on the gas supply pipeline to adjust the gas supply pressure flow. Preferably, the gas supply pipeline supplies argon (AR).

[0041] The pressure control unit 20 includes a mass flow control unit (MFC) 21 and a pressure sensor (PT) 22. Preferably, the flow control unit (MFC) 21 is located upstream of the pressure sensor (PT) 22, so as to adjust the opening of the mass flow control unit 21 by the set value of the pressure sensor 22 to maintain stable gas supply pressure control.

[0042] The air extraction valve unit 41 is provided on the air extraction pipeline 40 to control the air extraction pressure and flow rate. Preferably, the air extraction valve unit 41 includes a flow valve to provide accurate air extraction control.

[0043] Thus, the air supply pipeline providing back pressure connects the flow control unit 21 and the pressure sensor 22 to the bottom of the base 10 as a back pressure air supply system; another branch is connected to the vacuum pump 50 through the exhaust valve unit 41 as a vacuum system.

[0044] When wafer adsorption is required, the back pressure valve 31 and the exhaust valve unit 41 are opened, and the gas is sucked away by the vacuum pump 50, and the wafer W is sucked onto the base 10; when stable back pressure is required, the desired back pressure numerical signal is input to the pressure sensor 22, and the flow control unit 21 is opened to provide a quantitative supply of gas, so that the pressure of the pressure sensor 22 is stabilized at the input pressure value, and the stable back pressure control process is completed.

[0045] In one embodiment, Figure 2As shown, the downstream of the pressure control unit 20 is connected to the reaction chamber 100 through the pressure relief pipeline 60, and the opening is controlled by the pressure relief valve 61. Therefore, when back pressure and vacuum adsorption are not needed, the flow control unit 21 is closed to stop the gas supply, the back pressure valve 31 is closed, and the pressure relief valve 61 connected to the reaction chamber is opened. At this time, the vacuum pump 50 extracts the gas in the reaction chamber 100 through the pressure relief pipeline 60, so that the gas pressure in the reaction chamber 100 drops until it is consistent with the gas pressure of the back pressure pipeline 30, so that the pressure on the front and back sides of the wafer W is the same, the wafer W is released from the adsorption state, and the use of argon gas can be saved to avoid argon gas changing the environment in the reaction chamber 100.

[0046] Therefore, through the cooperation of the flow valve unit and the pressure control unit, a stable adsorption pressure can be provided for a complex back pressure conversion process.

[0047] However, in the aforementioned embodiment, the exhaust pressure and flow rate are adjusted solely by the exhaust valve unit 41 , and the adjustment margin is limited by the flow coefficient of the exhaust valve unit 41 . When only one range of MFC is used, the back pressure adjustment range is limited.

[0048] To this end, we propose Figure 3 In the embodiment, the exhaust valve unit 41 is configured as a regulating valve group 410, and the regulating valve group 410 includes a plurality of regulating valves connected in parallel, such as a first regulating valve 411, a second regulating valve 412, ..., an Nth regulating valve 41N. Through the parallel regulating valves, the gas flow rate of the exhaust pipeline 40 can be adjusted in a wide range by opening and closing a plurality of regulating valves at the same time or partially, thereby ensuring that a wide range of back pressures can be controlled under similar gas supply flows, and providing a stable wafer W adsorption function for complex back pressure conversion processes.

[0049] In one embodiment, the flow coefficient (CV) of each regulating valve is different. Therefore, by adjusting at least one regulating valve among the plurality of regulating valves with different flow coefficients, the gas flow rate of the exhaust pipeline 40 can be adjusted in a wide range, thereby ensuring that a wide back pressure range can be controlled under similar gas supply flow rates, and providing a stable wafer W adsorption function for complex back pressure conversion processes.

[0050] For the sake of explanation, we assume that Figure 3 The flow coefficients of the first regulating valve 411, the second regulating valve 412, and the Nth regulating valve 41N are in a decreasing relationship. That is, the flow coefficient of the first regulating valve 411 is the largest, and the flow coefficient of the Nth regulating valve 41N is the smallest.

[0051] If Figure 3As shown, when we need a smaller back pressure, we can open the first regulating valve 411. At this time, the flow of the exhaust pipeline 40 is relatively large, and the MFC can maintain a large flow to maintain stable pressure. On the contrary, when we need a larger back pressure, we close the first regulating valve 411 and open the Nth regulating valve 41N. At this time, the pipeline flow is relatively small, and the MFC can provide a large pressure with a small flow. When regulating valves with different flow coefficients are connected in parallel, the gas flow of the exhaust pipeline 40 can be controlled by switching multiple parallel regulating valves with different flow coefficients to obtain a wide range of back pressure.

[0052] The flow rate of the exhaust pipeline 40 can be controlled by switching a plurality of regulating valves with different flow coefficients in parallel, so that the adsorption pressure of the wafer W can be variably adjusted. Such a setting can realize the use of an MFC with one flow rate to variably adjust the adsorption pressure of the wafer W.

[0053] It can be understood that due to the setting of multiple parallel regulating valves with different flow coefficients in the regulating valve group 410, when a smaller back pressure is needed, all the regulating valves can even be opened; or when fine control is required, some regulating valves can be opened and closed to achieve a large range of gas flow regulation in the exhaust pipeline 40, thereby ensuring that a large back pressure range can be controlled under similar gas supply flow rates, and providing a stable wafer W adsorption function for complex back pressure conversion processes.

[0054] Figure 4 The valve opening process when partially changing the adsorption pressure is shown; the gas flow rate of the exhaust pipeline 40 can be controlled in parallel by multiple regulating valves with different flow coefficients, thereby ensuring that a large back pressure range can be controlled under the flow rate of similar AR GAS, and a stable wafer W adsorption function can be provided for complex back pressure change processes. It can be understood that Figure 4 The flow coefficients of the regulating valves are relative to each other, which means that from left to right in the figure, the flow coefficients of the regulating valves decrease; or it can be understood that from right to left, the flow coefficients of the regulating valves increase.

[0055] Preferably, the flow coefficients between the multiple regulating valves differ by multiples to maximize the adjustment range.

[0056] It should be noted that the regulating valve group 410 of the utility model includes multiple parallel regulating valves, and the regulating valve group 410 is located on the exhaust pipeline 40. Therefore, it can be understood that the multiple regulating valves in the regulating valve group 410 are connected in parallel with respect to all upstream and downstream pipeline components, so as to achieve the gas flow of the exhaust pipeline 40 to be adjusted over a large range by opening and closing multiple regulating valves at the same time or partially, thereby ensuring that a large back pressure range is controlled under similar gas supply flow, and providing a stable wafer W adsorption function for complex back pressure conversion processes.

[0057] In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the 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 operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0058] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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; 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.

[0059] Although the content of the utility model has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the utility model. After reading the above content, various modifications and substitutions of the utility model will be obvious to those skilled in the art. Therefore, the protection scope of the utility model should be limited by the attached claims.

Claims

1. A vacuum adsorption system, comprising a pedestal located in a reaction chamber, the pedestal being used to carry adsorbed wafers, a back pressure pipeline being provided in the pedestal, one end of the back pressure pipeline providing negative pressure to the surface of the pedestal to adsorb the wafers, characterized in that: The other end of the back pressure pipeline is connected to an air extraction pipeline and an air supply pipeline respectively. The air extraction pipeline is connected to a vacuum pump, and the vacuum pump extracts air to provide negative pressure. The gas supply pipeline is provided with a pressure control unit to adjust the gas supply pressure and flow; An air extraction valve unit is arranged on the air extraction pipeline to control the air extraction pressure and flow rate; The air extraction valve unit is configured as a regulating valve group, and the regulating valve group includes a plurality of regulating valves connected in parallel.

2. The vacuum adsorption system according to claim 1, characterized in that: A back pressure valve is arranged on the back pressure pipeline.

3. The vacuum adsorption system according to claim 1, characterized in that: The pressure control unit includes a mass flow control unit and a pressure sensor.

4. The vacuum adsorption system according to claim 3, characterized in that: The flow control unit is located upstream of the pressure sensor.

5. The vacuum adsorption system according to claim 2, characterized in that: The air extraction valve unit and the back pressure valve include a flow valve.

6. The vacuum adsorption system according to claim 1, characterized in that: The downstream of the pressure control unit is connected to the reaction chamber through a pressure relief pipeline, and the opening degree is controlled by a pressure relief valve.

7. The vacuum adsorption system according to claim 1, characterized in that: The flow coefficient of each regulating valve is different.

8. The vacuum adsorption system according to claim 7, characterized in that: The flow coefficients between the plurality of regulating valves differ by multiples.

9. A semiconductor processing device, characterized in that: Comprising the vacuum adsorption system according to any one of claims 1 to 8.

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