Control system and semiconductor device

Abstract

The embodiment of the invention provides a control system and semiconductor equipment, the control system comprises a cavity and a pipeline, the cavity comprises a heating electrostatic chuck, a wafer is adsorbed on the heating electrostatic chuck, and the pipeline is connected with the heating electrostatic chuck; back gas flows in the pipeline and is introduced between the wafer and the heating electrostatic chuck; the pipeline is sequentially provided with a controller, at least one stage of surge tank and a first vacuum pressure gauge according to the direction that back gas flows into the cavity, and the controller is connected with the first vacuum pressure gauge; wherein the at least one stage of surge tank is used for maintaining the stability of the pressure value of the back gas; the first vacuum pressure gauge is used for measuring a first pressure value of back gas between the wafer and the heating electrostatic chuck; and the controller is used for receiving the first pressure value and adjusting the flow value of the back gas input into the at least one stage of surge tank according to the first pressure value.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor technology, and more particularly to a control system and a semiconductor device. Background Technology

[0002] In the high-temperature ion implantation stage of semiconductor manufacturing, to ensure uniform heating of the entire wafer, after the wafer is placed on a heated electrostatic chuck for adsorption, a certain amount of backside gas (BSG) is introduced between the wafer and the chuck. As a heat transfer medium, the backside gas needs to be stable, controllable, and dynamically balanced. Furthermore, residual gas after preheating of each wafer needs to be promptly discharged from the pipeline. However, current technologies suffer from problems such as unstable backside gas and residual gas flowing into the process chamber. Summary of the Invention

[0003] This disclosure provides a control system and a semiconductor device.

[0004] In a first aspect, embodiments of this disclosure provide a control system comprising a cavity and a pipeline. The cavity includes a heated electrostatic chuck on which a wafer is adsorbed, and the pipeline is connected to the heated electrostatic chuck. A back gas flows through the pipeline and is introduced between the wafer and the heated electrostatic chuck. The pipeline is sequentially arranged with a controller, at least one stage of pressure stabilizing tank, and a first vacuum gauge in the direction in which the back gas flows into the cavity. The controller is connected to the first vacuum gauge.

[0005] The at least one pressure stabilizing tank is used to maintain the stability of the pressure value of the back gas;

[0006] The first vacuum pressure gauge is used to measure the first pressure value of the back gas between the wafer and the heated electrostatic chuck;

[0007] The controller is configured to receive and adjust the flow rate of the back gas input to the at least one level pressure stabilizing tank according to the first pressure value.

[0008] In some embodiments, the controller includes a first sub-controller and a second sub-controller, wherein the second sub-controller is connected to the first sub-controller and the first vacuum pressure gauge, respectively;

[0009] The second sub-controller is configured to control the first sub-controller to adjust the flow rate of the back gas input to the at least one level pressure stabilizing tank based on the first difference between the first pressure value and the first preset pressure value, so that the first difference meets the first preset condition.

[0010] In some embodiments, the pipeline is further provided with a second vacuum pressure gauge and a dry pump, the dry pump being disposed at one end of the pipeline, and the second vacuum pressure gauge being disposed between the heating electrostatic chuck and the dry pump;

[0011] The dry pump is used to remove the residual back gas;

[0012] The second vacuum pressure gauge is used to measure a second pressure value of the back gas when the back gas is purged.

[0013] In some embodiments, the pipeline is further provided with at least one flow regulating device;

[0014] The at least one flow regulating device is used to regulate the flow of the back gas.

[0015] In some embodiments, the at least one flow regulating device includes a first regulating device, a second regulating device, a third regulating device, a fourth regulating device, and a fifth regulating device;

[0016] The first regulating device is disposed between the gas source and the first sub-controller; the second regulating device is disposed between the first sub-controller and the at least one-stage pressure stabilizing tank; the third regulating device is disposed downstream of the first vacuum pressure gauge; the fourth regulating device is disposed between the heating electrostatic chuck and the second vacuum pressure gauge; the fifth regulating device is disposed between the third regulating device and the fourth regulating device, and also between the heating electrostatic chuck and the fourth regulating device.

[0017] The gas source is used to provide the back gas.

[0018] In some embodiments, when the back gas flows through the conduit between the wafer and the heated electrostatic chuck:

[0019] When the first pressure value is less than the first preset pressure value and the first difference does not meet the first preset condition, the first regulating device and the second regulating device are both in the open state, and the third regulating device, the fourth regulating device and the fifth regulating device are all in the closed state; until the first difference meets the first preset condition, the at least one flow regulating device is in the closed state.

[0020] When the first pressure value is greater than the first preset pressure value and the first difference does not meet the first preset condition, the third and fourth regulating devices are both in the open state, and the first, second, and fifth regulating devices are all in the closed state; until the first difference meets the first preset condition, the at least one flow regulating device is in the closed state.

[0021] In some embodiments, when the back gas is discharged through the conduit:

[0022] The first regulating device, the second regulating device, and the third regulating device are all in the off state, and the fourth regulating device and the fifth regulating device are all in the on state; the at least one flow regulating device is in the off state until the second difference between the second pressure value and the second preset pressure value meets the second preset condition.

[0023] In some embodiments, the control system further includes a machine tool control module, which is connected to the second sub-controller and the at least one flow regulating device, respectively, and is used to control the second sub-controller and the at least one flow regulating device.

[0024] In some embodiments, the control system further includes a third vacuum gauge and at least one cold pump, both of which are connected to the cavity;

[0025] The third vacuum gauge is used to measure the third pressure value of the cavity;

[0026] The at least one cold pump is used to adsorb the back gas remaining in the cavity.

[0027] In some embodiments, the first difference is negatively correlated with the sum of the volumes of the at least one pressure stabilizing tank.

[0028] In some embodiments, the at least one flow regulating device is a pneumatic valve.

[0029] In a second aspect, embodiments of this disclosure provide a semiconductor device, the semiconductor device including at least a control system as described in any of the first aspects.

[0030] This disclosure provides a control system and a semiconductor device. The control system includes a cavity and a pipeline. The cavity includes a heated electrostatic chuck, on which a wafer is adsorbed. The pipeline is connected to the heated electrostatic chuck. Back gas flows through the pipeline and enters between the wafer and the heated electrostatic chuck. The pipeline is sequentially arranged with a controller, at least one pressure stabilizing tank, and a first vacuum gauge in the direction of back gas inflow into the cavity. The controller is connected to the first vacuum gauge. The at least one pressure stabilizing tank is used to maintain a stable back gas pressure. The first vacuum gauge is used to measure a first pressure value of the back gas between the wafer and the heated electrostatic chuck. The controller receives and adjusts the flow rate of the back gas input to the at least one pressure stabilizing tank based on the first pressure value. Thus, the pressure value of the back gas can be stabilized and its fluctuations minimized through the at least one pressure stabilizing tank. Furthermore, the controller can adjust the flow rate of the back gas to adjust the first pressure value, thereby achieving closed-loop control of the first vacuum gauge and automatically adjusting the back gas at different pressure values. Attached Figure Description

[0031] Figure 1 A schematic diagram of the composition structure of a control system provided for related technologies. Figure 1 ;

[0032] Figure 2 A schematic diagram of the composition structure of a control system provided for related technologies. Figure 2 ;

[0033] Figure 3 A schematic diagram of a pressure curve for a cavity provided for related technologies;

[0034] Figure 4 A schematic diagram of the composition structure of a control system provided for related technologies. Figure 3 ;

[0035] Figure 5 A schematic diagram of a control system provided for related technologies;

[0036] Figure 6 A schematic diagram of a pressure curve provided for related technologies;

[0037] Figure 7 A schematic diagram of the composition structure of a control system provided in this disclosure embodiment. Figure 1 ;

[0038] Figure 8 A schematic diagram of the composition structure of a control system provided in this disclosure embodiment. Figure 2 ;

[0039] Figure 9 A schematic diagram of the composition structure of a control system provided in this disclosure embodiment. Figure 3 ;

[0040] Figure 10 A schematic model provided for an embodiment of this disclosure. Figure 1 ;

[0041] Figure 11 A schematic model provided for an embodiment of this disclosure. Figure 2 ;

[0042] Figure 12 A schematic model provided for an embodiment of this disclosure. Figure 3 ;

[0043] Figure 13 A schematic diagram of a pressure curve provided for an embodiment of this disclosure;

[0044] Figure 14 This is a schematic diagram of the composition structure of a semiconductor device provided in an embodiment of this disclosure. Detailed Implementation

[0045] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for explaining the relevant applications and are not intended to limit the scope of this disclosure. Furthermore, it should be noted that, for ease of description, only the parts relevant to the relevant applications are shown in the accompanying drawings.

[0046] 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 disclosure belongs. The terminology used herein is for the purpose of describing embodiments of this disclosure only and is not intended to be limiting of this disclosure.

[0047] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0048] It should be noted that the terms "first, second, third" used in the embodiments of this disclosure are merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first, second, third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of this disclosure described herein can be implemented in an order other than that illustrated or described herein.

[0049] See Figure 1 It illustrates a schematic diagram of the composition structure of a control system provided by related technologies. Figure 1 .like Figure 1As shown, the control system 10 includes a process chamber (hereinafter referred to as the chamber) 11 and a pipeline 12. The chamber 11 includes a heated electrostatic chuck 111, on which a wafer (also referred to as a wafer) is adsorbed. The pipeline 12 is connected to the heated electrostatic chuck 111. Back gas flows through the pipeline 12 and is introduced into the heated electrostatic chuck 111 through the pipeline 12, thereby filling the space between the back of the wafer and the heated electrostatic chuck 111. The pipeline 12 is equipped with a pneumatic valve 121, through which the back gas flowing through the pneumatic valve 121 flows into the chamber 11 through the gap between the wafer and the heated electrostatic chuck 111.

[0050] like Figure 1 As shown, the control system 10 also includes a vacuum pressure gauge 13 and at least one cold pump 14. The vacuum pressure gauge 13 is used to measure the pressure value of the cavity 11, and the at least one cold pump 14 is used to adsorb residual back gas (referred to as residual gas) in the cavity 11. For example, the control system 10 includes three cold pumps 14, namely cold pumps 14-1, 14-2, and 14-3, but the number of cold pumps 14 can also be four or other values, depending on the actual situation, and is not specifically limited thereto. Furthermore, the principle of the cold pump is to adsorb gas molecules at low temperature, then heat up and discharge the adsorbed gas, and then cool it down again, thus achieving adsorption force. Therefore, after the cold pump adsorbs a certain amount of gas, it needs to be maintained.

[0051] In this embodiment, the cavity 11 achieves a high vacuum environment through three cold pumps 14, with a vacuum of 3.0 to 5.0 E-6 Torr; the vacuum between the wafer and the heated electrostatic chuck 111 is 4 to 10 Torr, which is significantly different from the vacuum of the cavity 11.

[0052] It should be noted that the back gas can also be called the reverse gas or the back-side gas. The back gas can be nitrogen, such as PN2, or other gases such as helium; there is no specific limitation. The back gas is supplied by a gas source, such as plant bulk gas.

[0053] It should also be noted that excessive gas and high pressure on the back side can weaken the adhesion of the electrostatic chuck 111, posing a risk of wafer displacement or detachment. Conversely, insufficient gas and low pressure on the back side can result in poor heating performance of the electrostatic chuck 111. Therefore, it is necessary to maintain a dynamic balance in the back gas. Furthermore, residual gas after preheating of each wafer must be promptly discharged through pipe 12; otherwise, it will flow directly into cavity 11, increasing the load on cold pump 14, shortening its maintenance cycle, and also affecting the vacuum environment of cavity 11.

[0054] In related technology 1, based on Figure 1 The control system 10 shown is as follows: Figure 2As shown, with the cavity 11, vacuum gauge 13, and at least one cold pump 14 remaining unchanged, the pipeline 12 is sequentially equipped with a pressure reducing valve, a pneumatic valve 1, a needle valve, and a pneumatic valve 2 in the direction of gas inflow into the cavity 11. The pressure reducing valve is used to reduce the pressure of the high-pressure back gas (e.g., PN2), the needle valve is used to control the amount of the final back gas, and the pneumatic valves 1 and 2 are used to switch the back gas on and off.

[0055] In this related technology 1, the adaptability to different back gas requirements is poor. Changes in the back gas must be made by manually adjusting the needle valve, which is a cumbersome process. The stability of each gas supply is uncertain, and the flow rate of the back gas is greatly affected by the inlet pressure. Secondly, the monitoring methods and techniques are inadequate. Specifically, the needle valve is a purely mechanical device and cannot monitor the flow rate and pressure of the back gas. It can only be roughly judged by related parameters (e.g., the vacuum of chamber 11). In addition, the residual gas handling method is inadequate. There is no exhaust pipe, and the residual gas will flow directly into chamber 11 and be absorbed by the cold pump 14. The pipes 12 are all connected by flexible hoses, which are easily bent and blocked by movement and contact, causing instability in the back gas.

[0056] The flow rate and pressure of the back gas can be monitored using associated parameters, for example, see [link to relevant documentation]. Figure 3 It shows a schematic diagram of a pressure curve for a cavity provided by related technology, with the horizontal axis representing time and the vertical axis representing the pressure value (in Torr). Figure 3 As shown, from the perspective of signal detection and discrimination, when the wafer is removed from the preheating plate (i.e., the heating electrostatic chuck 111), the back gas trapped inside (i.e., the back gas from pneumatic valve 2 to the heating electrostatic chuck 111) will be released. The pulse fluctuation signal caused by the vacuum pressure of the cavity 11 when the trapped back gas is released can be detected, discerned, and judged by software. The logic and specifications of the judgment are based on the process settings and are not limited thereto. For example, when the pressure value corresponding to the pulse height exceeds 1.0000E-05 Torr, the amount of back gas is considered sufficient; if it does not exceed this amount, it is considered insufficient. This related parameter can be used to control the back gas. Understandably, the more back gas trapped, the greater the pressure value exceeding 1.0000E-05 Torr will be, and the higher the pulse corresponding to the pressure value will be. That is, a higher pulse indicates more back gas is introduced, and a lower pulse indicates less back gas is introduced. By monitoring the pulse height, the amount of trapped back gas can be characterized.

[0057] In related technology 2, based on Figure 1 The control system 10 shown is as follows: Figure 4As shown, with the cavity 11, vacuum gauge 13 and at least one cold pump 14 remaining unchanged, the pipeline 12 is equipped with a P controller, a three-way valve and a pneumatic valve in sequence according to the direction of gas inflow into the cavity.

[0058] Figure 5 for Figure 4 The corresponding schematic diagram shows that V39 corresponds to a three-way valve and V73 corresponds to a pneumatic valve; V33 and V32 are pneumatic valves required for exhaust to discharge residual gas to the extraction device.

[0059] It should be noted that Pcontroller is a controller that has the functions of a mass flow controller (MFC) and a pressure controller.

[0060] See Figure 6 The diagram illustrates a pressure curve provided by related technologies. Specifically, the left vertical axis (2, 2.5, 3, etc.) represents the coordinate range corresponding to the back gas, and the right vertical axis (3.00E-06, 3.20E-06, 3.40E-06, etc.) represents the coordinate range corresponding to the cavity 11. Solid lines represent pressure changes in the back gas, and dashed lines represent pressure changes in the cavity 11. Figure 6 As shown, when the back gas is open, the pressure value of the back gas is 2.21 Torr, and the pressure value of the cavity 11 is 3.78E-6 Torr; when the back gas is stable, the pressure value of the back gas is 3.88 Torr, and the pressure value of the cavity 11 is 4.21E-6 Torr. The pressure values ​​of the cavity 11 corresponding to the back gas in different states (open, stable) can be obtained through different curves.

[0061] It should be noted that the stable pressure of the back gas is 3.88 Torr. The pressure of the back gas fluctuates between a minimum of 2.21 Torr and a maximum of 4.33 Torr. Compared with the stable pressure, the actual pressure fluctuates within a range of approximately -43% to 12%. In other words, the actual pressure fluctuates within a range of approximately -43% to 12% of the stable pressure.

[0062] In this related technology 2, the actual pressure position controlled by Pcontroller is far from the heating electrostatic chuck 111, and the pressure cannot reflect the required pressure between the wafer and the heating electrostatic chuck 111 in a timely manner; moreover, the pressure fluctuation is large during the initial period of pressure control.

[0063] In summary, this disclosure provides a control system comprising a cavity and a pipeline. The cavity includes a heated electrostatic chuck, on which a wafer is adsorbed. The pipeline is connected to the heated electrostatic chuck. Back gas flows through the pipeline and enters between the wafer and the heated electrostatic chuck. The pipeline is sequentially arranged with a controller, at least one pressure stabilizing tank, and a first vacuum gauge in the direction of back gas inflow into the cavity. The controller is connected to the first vacuum gauge. The at least one pressure stabilizing tank is used to maintain a stable back gas pressure. The first vacuum gauge is used to measure a first pressure value of the back gas between the wafer and the heated electrostatic chuck. The controller receives and adjusts the flow rate of the back gas input to the at least one pressure stabilizing tank based on the first pressure value. Thus, the pressure value of the back gas can be stabilized and its fluctuations minimized through the at least one pressure stabilizing tank. Furthermore, the controller can adjust the flow rate of the back gas to adjust the first pressure value, thereby achieving closed-loop control of the first vacuum gauge and automatically adjusting the back gas at different pressure values.

[0064] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0065] In one embodiment of this disclosure, see Figure 7 It illustrates a schematic diagram of the composition structure of a control system provided in an embodiment of this disclosure. Figure 1 .like Figure 7 As shown, the control system 20 may include a cavity 21 and a pipeline 22. The cavity 21 includes a heated electrostatic chuck 211, on which the wafer is adsorbed. The pipeline 22 is connected to the heated electrostatic chuck 211. Back gas flows in the pipeline 22 and is introduced between the wafer and the heated electrostatic chuck 211. The pipeline 22 is sequentially arranged with a controller 221, at least one stage pressure stabilizing tank 222, and a first vacuum pressure gauge 223 in the direction of back gas inflow into the cavity 21. The controller 221 is connected to the first vacuum pressure gauge 223.

[0066] At least one pressure stabilizing tank 222 is used to maintain the stability of the back gas pressure value;

[0067] The first vacuum pressure gauge 223 is used to measure the first pressure value of the back gas between the wafer and the heated electrostatic chuck 211;

[0068] The controller 221 is used to receive and adjust the flow rate of the back gas input to at least one pressure tank 222 according to a first pressure value.

[0069] In this embodiment, the control system 20 is specifically a back gas stabilization control system. This control system 20 is applied during the high-temperature ion implantation stage to ensure stable and controllable back gas during high-temperature ion implantation of each wafer. Stable back gas means minimal fluctuations in the back gas, resulting in better adsorption force and heating effect of the heating electrostatic chuck 211.

[0070] Here, the back gas is introduced into the heated electrostatic chuck 211 through pipe 22, thereby filling the space between the back of the wafer and the heated electrostatic chuck 211. Furthermore, the direction of the back gas flow into the cavity 21 specifically refers to the flow direction from the gas source into the cavity 21. The gas source is used to provide the back gas.

[0071] It should be noted that cavity 21 is specifically a process cavity, which can also be called a chamber; the first vacuum pressure gauge 223 can also be called vacuum pressure gauge 1; the controller 221 can be a P controller, which has the functions of MFC and pressure controller.

[0072] In related technology 2, the Pcontroller is used to monitor the pressure value of the back gas between the wafer and the heated electrostatic chuck 111. The actual pressure position it controls is far from the heated electrostatic chuck 111, about 2 to 3 meters away. However, in this embodiment, the first vacuum pressure gauge 223 is used to monitor the pressure value of the back gas between the wafer and the heated electrostatic chuck 211. The position of the Pcontroller is equivalent to the position of the controller 221. The position of the first vacuum pressure gauge 223 is significantly closer to the cavity 21 than that of the controller 221, and it better represents the actual needs, allowing it to reflect the required pressure in a timely manner.

[0073] It should also be noted that the volume of the pressure stabilizing tank 222 is larger than that of the rest of the pipeline. This larger volume in the pressure stabilizing tank 222 helps maintain a stable pressure value for the incoming back gas. Furthermore, the number of pressure stabilizing tanks 222 can be multiple or a single tank, depending on the actual situation, and there is no limitation in this regard. For example, the control system 20 includes two-stage pressure stabilizing tanks 222 (u1 and u2). After the back gas passes through at least one stage of pressure stabilizing tank 222, the fluctuation of the back gas can be reduced; specifically, the fluctuation of the back gas pressure value can be reduced. That is, at least one stage of pressure stabilizing tank 222 can reduce the fluctuation of the first vacuum pressure gauge 223.

[0074] It should also be noted that the controller 221 can achieve closed-loop control of the back gas pressure by controlling and adjusting the flow rate of the back gas input to at least one level pressure stabilizing tank 222 based on the first pressure value monitored by the first vacuum pressure gauge 223.

[0075] This disclosure provides a control system 20 that can reduce fluctuations in the first vacuum pressure gauge 223, achieve closed-loop control of the first vacuum pressure gauge 223, and realize automatic adjustment of different pressures of the back gas.

[0076] In some embodiments, such as Figure 7 As shown, the pipeline 22 is also equipped with a second vacuum pressure gauge 224 and a dry pump 225. The dry pump 225 is located at one end of the pipeline 22, and the second vacuum pressure gauge 224 is located between the heating electrostatic chuck 211 and the dry pump 225.

[0077] Dry pump 225 is used to remove residual back gas;

[0078] The second vacuum pressure gauge 224 is used to measure the second pressure value of the back gas when the back gas is being expelled.

[0079] Specifically, the dry pump 225 is located at the exhaust end of the pipeline 22.

[0080] It should be noted that the second vacuum pressure gauge 224 can also be referred to as vacuum pressure gauge 2. When residual back gas is being expelled, the second vacuum pressure gauge 224 is used to monitor the second pressure value and bring it close to the second preset pressure value; when the second pressure value is close to the second preset pressure value, the dry pump 225 stops expelling the residual gas. The second preset pressure value is the maximum target pressure value that the residual back gas can reach, and it can be set according to the actual situation without being specifically limited. In this way, through the second vacuum pressure gauge 224 and the dry pump 225, the residual gas can be stably discharged, and the residual gas will not flow into the cavity 21 and will not affect the vacuum environment of the cavity 21.

[0081] In some embodiments, based on Figure 7 The control system 20 shown is referred to in the following text. Figure 8 It illustrates a schematic diagram of the composition structure of a control system provided in an embodiment of this disclosure. Figure 2 .like Figure 8 As shown, the controller 221 includes a first sub-controller 2211 and a second sub-controller 2212, and the second sub-controller 2212 is connected to the first sub-controller 2211 and the first vacuum pressure gauge 223 respectively.

[0082] The second sub-controller 2212 is used to control the first sub-controller 2211 to adjust the flow rate of the back gas input to at least one level pressure tank 222 according to the first difference between the first pressure value and the first preset pressure value, so that the first difference meets the first preset condition.

[0083] It should be noted that when controller 221 is a standalone device, it can be a Pcontroller with control and regulation functions. When controller 221 includes a first sub-controller 2211 and a second sub-controller 2212, the first sub-controller 2211 can be an MFC (Multi-Functional Controller), and the second sub-controller 2212 is used to send control signals to the first sub-controller 2211 to regulate the back gas flow rate. In this embodiment, controller 221 can be a standalone device, or controller 221 can include a first sub-controller 2211 and a second sub-controller 2212, and the second sub-controller 2212 controls the first sub-controller 2211 to regulate the back gas flow rate; no specific limitation is made in this regard. Exemplarily, the specific implementation of this embodiment is described in detail using the example of controller 221 including a first sub-controller 2211 and a second sub-controller 2212.

[0084] It should be noted that the first preset pressure value is the target pressure value that the back gas between the wafer and the heated electrostatic chuck 211 needs to reach. It can be set according to the actual situation and is not specifically limited. For example, the first preset pressure value is 3.88 Torr.

[0085] In some embodiments, the first preset condition includes: the error range of the first difference (i.e., the percentage of the first difference to the first preset pressure value) is less than or equal to 5%.

[0086] It should be noted that when the first pressure value and the first preset pressure value are equal, the first difference is equal to 0, and at this time there is no error between the first pressure value and the first preset pressure value. In the actual manufacturing process, the error range can be set according to the process flow. When the first difference does not meet the first preset condition, the flow rate of the back gas input to at least the first-stage pressure stabilizing tank 222 is adjusted; when the first difference meets the first preset condition, the back gas does not need to be adjusted.

[0087] It should also be noted that the specific content of the first preset condition, namely the target value that the error range of the first difference needs to reach, can also be other values ​​such as 1%, 2%, or 6%, and there is no specific limitation on this.

[0088] In some embodiments, such as Figure 8 As shown, the pipeline 22 is also equipped with at least one flow regulating device 226 (not shown in the figure);

[0089] At least one flow regulating device 226 is used to regulate the flow of back gas.

[0090] Understandably, at least one flow regulating device 226 can be used to switch the back gas. When there are multiple flow regulating devices 226, different flow regulating devices 226 are controlled to be in different states under different conditions.

[0091] In some embodiments, such as Figure 8 As shown, at least one flow regulating device 226 includes a first regulating device a1, a second regulating device a2, a third regulating device a3, a fourth regulating device a4, and a fifth regulating device a5;

[0092] The first regulating device a1 is disposed between the gas source and the first sub-controller 2211; the second regulating device a2 is disposed between the first sub-controller 2211 and at least one level pressure stabilizing tank 222; the third regulating device a3 is disposed downstream of the first vacuum pressure gauge 223; the fourth regulating device a4 is disposed between the heating electrostatic chuck 211 and the second vacuum pressure gauge 224; the fifth regulating device a5 is disposed between the third regulating device a3 and the fourth regulating device a4, and is also disposed between the heating electrostatic chuck 211 and the fourth regulating device a4.

[0093] The gas source is used to provide gas to the back.

[0094] It should be noted that the gas source can be bulk gas, but there are no specific limitations on this.

[0095] For example, such as Figure 8 As shown, at least one flow regulating device 226 includes five regulating devices (a1-a5). Depending on actual needs, at least one flow regulating device 226 may also include other numbers of regulating devices, and no specific limitation is made thereto.

[0096] In some embodiments, at least one flow regulating device 226 may be a pneumatic valve.

[0097] Here, the first regulating device a1 can also be called pneumatic valve 1, the second regulating device a2 can also be called pneumatic valve 2, the third regulating device a3 can also be called pneumatic valve 3, the fourth regulating device a4 can also be called pneumatic valve 4, and the fifth regulating device a5 can also be called pneumatic valve 5.

[0098] It should be noted that at least one flow regulating device 226 can also be other non-purely mechanical devices that can be controlled by software, and no specific limitation is made in this regard.

[0099] In some embodiments, when back gas flows through conduit 22 between the wafer and the heated electrostatic chuck 211:

[0100] When the first pressure value is less than the first preset pressure value and the first difference does not meet the first preset condition, the first regulating device a1 and the second regulating device a2 are both in the open state, and the third regulating device a3, the fourth regulating device a4 and the fifth regulating device a5 are all in the closed state; until the first difference meets the first preset condition, at least one flow regulating device 226 is in the closed state.

[0101] When the first pressure value is greater than the first preset pressure value and the first difference does not meet the first preset condition, the third regulating device a3 and the fourth regulating device a4 are both in the open state, and the first regulating device a1, the second regulating device a2 and the fifth regulating device a5 are all in the closed state; until the first difference meets the first preset condition, at least one flow regulating device 226 is in the closed state.

[0102] It should be noted that during normal process (i.e., high-temperature ion implantation stage) and gas flow, before the wafer is transferred to the heated electrostatic chuck 211 and during the process recipe tuning, it is necessary to check whether the first pressure value of the first vacuum pressure gauge 223 matches the process recipe, that is, whether the first difference meets the first preset condition.

[0103] If the first pressure value is less than the first preset pressure value and the first difference does not meet the first preset condition, then pneumatic valves 1 and 2 are opened directly, and the remaining pneumatic valves (pneumatic valves 3, 4, and 5) are closed, with controller 221 maintaining a constant output. When the first difference meets the first preset condition, specifically, when the first pressure value reaches the first preset pressure value, pneumatic valves 1 and 2 are closed. If the first pressure value is greater than the first preset pressure value and the first difference does not meet the first preset condition, then pneumatic valves 3 and 4 are opened first, and the remaining pneumatic valves (pneumatic valves 1, 2, and 5) are closed. When the first pressure value reaches the first preset pressure value, pneumatic valves 3 and 4 are closed.

[0104] It should be noted that because the pneumatic valve closes with a delay, the initial pressure value will be lower than the first preset pressure value after it is fully closed. In this case, continue inflation as described above. Additionally, there is no delay when the pneumatic valve is continuously open, but there is a delay when the valve first opens, which can lead to over-inflation. In this case, deflate the gas as described above.

[0105] It should also be noted that after the wafer is fed into the heated electrostatic chuck 211 and attracted, pneumatic valves 1, 2, 3, and 5 are opened, and pneumatic valve 4 is closed. Back gas flows into the contact surface between the wafer and the heated electrostatic chuck 211. Because the volume of the exhaust pipe is small, the error range of the first difference in this embodiment can be less than 1%. At this time, the setpoint of the fine-tuning controller 221 is adjusted so that the flow rate of the back gas equals the flow rate of the overflowing back gas. The entire control system 20 achieves dynamic balance, ensuring that the first vacuum pressure gauge 223 remains stable and the process proceeds normally. Here, the small amount of overflowing back gas can be attracted by the cold pump.

[0106] It should also be noted that there is a gap between the wafer and the heated electrostatic chuck 211, and a small amount of back gas continuously flows into the gap and is discharged from the gap and adsorbed. The flow rate of the overflowing back gas refers to the required flow rate of back gas between the wafer and the heated electrostatic chuck 211, or the required flow rate of back gas in the pipeline 22.

[0107] In some embodiments, when back gas is discharged through pipe 22:

[0108] The first regulating device a1, the second regulating device a2, and the third regulating device a3 are all in the closed state, while the fourth regulating device a4 and the fifth regulating device a5 are all in the open state; at least one flow regulating device 226 is in the closed state until the second difference between the second pressure value and the second preset pressure value meets the second preset condition.

[0109] In some embodiments, the second preset condition includes: the error range of the second difference (i.e., the percentage of the second difference to the second preset pressure value) is less than or equal to 5%.

[0110] It should be noted that when the second pressure value is equal to the second preset pressure value, the second difference is equal to 0, and at this time there is no error between the second pressure value and the second preset pressure value. In the actual manufacturing process, this error range can be set according to the process flow. When the second difference does not meet the second preset condition, the residual gas is removed by the dry pump 225; when the second difference meets the second preset condition, the dry pump 225 stops removing the residual gas.

[0111] It should also be noted that the specific content of the second preset condition, namely the target value that the error range of the second difference needs to reach, can also be other values ​​such as 1%, 2%, or 6%, and there is no specific limitation on this.

[0112] It should be noted that when the process is completed and venting is performed, there is still back gas between the wafer and the heated electrostatic chuck 211. The suction force of the heated electrostatic chuck 211 is maintained. Pneumatic valves 1, 2, and 3 are closed, and pneumatic valves 4 and 5 are opened. The back gas between the wafer and the heated electrostatic chuck 211, as well as the residual gas in pipeline 22 (specifically, the pipeline 22 between pneumatic valve 1 and pneumatic valve 4, and between pneumatic valve 5 and the heated electrostatic chuck 211), is pumped away by the dry pump 225. By monitoring the second pressure value of the second vacuum pressure gauge 224, when the second difference meets the second preset condition, specifically, when the second pressure value reaches the second preset pressure value, pneumatic valves 4 and 5 are closed. At this time, the suction force of the heated electrostatic chuck 211 is released, and the wafer with the completed process is removed; the next wafer that has not undergone processing is introduced, and the normal process of gas introduction is repeated.

[0113] In some embodiments, such as Figure 8 As shown, the control system 20 may further include a machine control module 23, which is connected to the second sub-controller 2212 and at least one flow regulating device 226 respectively (the connection between the machine control module 23 and at least one flow regulating device 226 is not shown in the figure), and is used to control the second sub-controller 2212 and at least one flow regulating device 226.

[0114] Here, the machine control module 23 can also be referred to as the main machine control system. The machine control module 23 sends control signals to the second sub-controller 2212, and the second sub-controller 2212 controls the first sub-controller 2211 to adjust the flow rate of the back gas.

[0115] It should be noted that if the controller 221 is an independent device, the machine control module 23 can also be used to control the controller 221.

[0116] It should also be noted that the machine control module 23 can also receive the second pressure value and control at least one flow regulating device 226 to make the second difference meet the second preset condition.

[0117] It should also be noted that the first preset pressure value is set in the process recipe, and then imported from the process recipe in the machine control module 23 to the second sub-controller 2212 through interactive communication between the machine control module 23 and the second sub-controller 2212. This allows for closed-loop control of the first vacuum pressure gauge 223 based on the first pressure value and the first preset pressure value. Additionally, the second preset pressure value is also set as a constant in the machine control module 23.

[0118] In some embodiments, based on Figure 8 The control system 20 shown is referred to in the following text. Figure 9 It illustrates a schematic diagram of the composition structure of a control system provided in an embodiment of this disclosure. Figure 3.like Figure 9 As shown, the control system 20 may also include a third vacuum gauge 24 and at least one cold pump 25, both of which are connected to the cavity 21.

[0119] The third vacuum gauge 24 is used to measure the third pressure value of the cavity 21;

[0120] At least one cold pump 25 is used to adsorb residual back gas in the cavity 21.

[0121] Here, the third vacuum pressure gauge 24 can also be referred to as vacuum pressure gauge 3.

[0122] For example, the control system 20 includes three cold pumps 25, namely cold pump 25-1, 25-2 and 25-3, but the number of cold pumps 25 can also be four or other values, depending on the actual situation, and there is no specific limitation.

[0123] It should be noted that in this embodiment, the residual gas is mainly removed through the second vacuum pressure gauge 224 and the dry pump 225, and at least one cold pump 25 is used to adsorb trace amounts of back gas. The second vacuum pressure gauge 224 and the dry pump 225 allow the residual gas to be removed through the pipeline 22, preventing it from flowing into the cavity 21, reducing the load on the cold pump 25, extending the maintenance cycle of the cold pump 25, and avoiding any impact on the vacuum environment of the cavity 21.

[0124] In some embodiments, the first difference is negatively correlated with the sum of the volumes of at least one pressure vessel 222.

[0125] For example, such as Figures 7 to 9 As shown, the two-stage pressure stabilizing tanks 222 have volumes of 10 liters (L) (pressure stabilizing tank u1) and 2L (pressure stabilizing tank u2), respectively, with a total volume of 12L. A theoretical model is established based on this, and data simulations are performed. See [link / reference] Figure 10 It illustrates a model schematic provided by an embodiment of this disclosure. Figure 1 .like Figure 10 As shown, the volume of the target chamber is V, and the real-time pressure of the target chamber is P. t P t The changes are caused by the intake flow rate F and the extraction flow rate F e The decision is made that the intake air flow rate F is controlled by the P controller (i.e., controller 221) using PID (Proportional, Integral, and Derivative) closed-loop control, and the extraction air flow rate F... e The pressure P at the extraction end e (relative to chamber pressure P) t (its basic value is constant) and the chamber pressure P tDecide.

[0126] It should be noted that, Figure 10 The volume V of the target chamber is equivalent to Figure 8 or Figure 9 The sum of the volumes of the first regulating device a1 (pneumatic valve 1) to the wafer and the fifth regulating device a5 (pneumatic valve 5) to the fourth regulating device a4 (pneumatic valve 4); the isolation valve is equivalent to the third regulating device a3 (pneumatic valve 3), and the target plate is equivalent to the heating electrostatic chuck 211.

[0127] The flow rate PID control formula is shown in formula (1):

[0128]

[0129] Where, k p k represents the proportionality coefficient. i k represents the integral coefficient. D P represents the differential coefficient; t Indicates real-time pressure; P T This represents the final target pressure, which is a constant.

[0130] The relationship between flow rate and pressure is shown in formula (2):

[0131] F e =(P t -P e )D e (2)

[0132] Among them, D e This represents the flow resistance, which is a constant.

[0133] The relationship between volume and flow rate is shown in formula (3):

[0134] d(P t -P0)*V=(FF e )dt (3)

[0135] It should be noted that formula (3) is derived based on the ideal gas law PV=nRT. Where P represents gas pressure; V represents gas volume; n represents gas mass; R represents gas constant; T represents gas temperature; and P0 represents initial pressure, which is a constant.

[0136] The pressure P is obtained from formulas (1), (2) and (3). t The equation relating time is shown in formula (4):

[0137]

[0138] Furthermore, the pressure P can be obtained according to formula (4). tThe change over time is shown in formula (5):

[0139]

[0140] in, c1=(P T -P0), which is only related to the target pressure and the initial pressure, that is, the initial oscillation amplitude, which is the difference that needs to be adjusted, and it is a constant.

[0141]

[0142] Therefore, the pressure P can be analyzed according to formula (5). t Changes over time. Specifically, firstly, P t It will revolve around the target pressure P T The oscillation approaches P as time increases. T Secondly, P t The oscillation amplitude, oscillation period, and decay rate are determined by four parameters: a, b, c1, and c2, which are determined by the PID parameters (k) of the Pcontroller. p k i k D The volume V of the target chamber and the flow resistance D of the pipe. e Once the decision is made, these parameters can be adjusted according to actual needs.

[0143] It should be noted that, with the PID parameters fixed, the volume V of the target chamber is related to P. t The effect of the time curve is that when the volume from the Pcontroller to the isolation valve and the volume from the isolation valve to the target plate vary greatly (e.g., nearly a hundredfold), Figure 10 Since V1 and V2 in the equation can be ignored, the PID parameters can be simplified to the following equation (6):

[0144]

[0145] The oscillation amplitude is Oscillation time is

[0146] Based on Boyle's law P1V1=P2V2, the minimum value of the oscillation amplitude is derived. When ventilated, the isolation valve opens, and the volume increases. Specifically, the pipeline pressure when ventilated is P1, and the volume is V1; the pipeline pressure when ventilated is P2, and the volume is V1+V2.

[0147] See Figure 11 It illustrates a model schematic provided by an embodiment of this disclosure. Figure 2 Specifically, this is a volume comparison diagram of the back of the body before and after the introduction of gas, as described in related technology 2. For example... Figure 11As shown, let P1 = 3.88 Torr, and V1 = 0.13 L and V2 = 0.1 L. Then P2 = P1V1 / (V1+V2) = 3.88 * 0.13 / (0.13 + 0.1) = 2.2 Torr. See also Figure 12 It illustrates a model schematic provided by an embodiment of this disclosure. Figure 3 Specifically, this is a schematic diagram comparing the volume of gas introduced into the back of the body before and after the gas was introduced. For example... Figure 12 As shown, P1 is set the same, P1 = 3.88 Torr, and V1 = 12L, V2 = 0.1L. Then P2 = P1V1 / (V1+V2) = 3.88*12 / (12+0.1) = 3.84 Torr.

[0148] In summary, the minimum oscillation amplitude depends on the pipeline volume design. Because V1 in this disclosure is modified to be larger, the minimum oscillation amplitude in this disclosure is significantly reduced.

[0149] Furthermore, based on the ideal gas law PV=nRT, the maximum value of the oscillation amplitude is derived, which represents the first overshoot value under the same PID parameter setting control.

[0150] It should be noted that the gas mass quantity *n* depends on the amount of gas flowing into the pipeline, and the gas volume is equal to the product of the gas mass flow rate and time. The gas mass flow rate is typically 10 standard cubic centimeters per minute (sccm), and its value is controlled by the P controller using PID parameters. Under a fixed response time and the same PID parameters, the amount of gas flowing in is the same.

[0151] It should also be noted that formula (7) is derived from the ideal gas law PV=nRT:

[0152] ΔP1*V1=ΔP2*V2 (7)

[0153] Wherein, ΔP1 and V1 are the pressure change and volume in related technology 2, respectively; ΔP2 and V2 are the pressure change and volume in this disclosure, respectively.

[0154] ΔP2=ΔP1*V1 / V2=(P1 Max-P1 Baseline)*V1 / V2. Where, P1 Max represents the maximum pressure value of the back gas in related technology 2, which is 4.33 Torr; P1 Baseline represents the pressure value at steady state in related technology 2, which is 3.88 Torr.

[0155] Therefore, ΔP2 = (4.33 - 3.88) * (0.13 + 0.1) / (12 + 0.1) = 0.009 Torr.

[0156] Since ΔP2 = P2 Max - P2 Baseline, we can derive P2 Max = P2 Baseline + ΔP2. Here, P2Max represents the maximum pressure value of the back gas in this disclosure; P2 Baseline represents the stable pressure value in this disclosure, which is equal to that in related technology 2, also 3.88 Torr.

[0157] Therefore, P2 Max = 3.88 + 0.009 = 3.89 Torr. In other words, under the same PID parameters and time, the maximum oscillation amplitude is significantly reduced in designs with larger pipeline volumes (i.e., this disclosure).

[0158] In this disclosure, the stable pressure of the back gas is 3.88 Torr, and the pressure fluctuates between a minimum of 3.84 Torr and a maximum of 3.89 Torr. The actual pressure fluctuates within a range of approximately -1% to 0.3% compared to the stable pressure. In related technology 2, the actual pressure fluctuates within a range of approximately -43% to 12% compared to the stable pressure. Therefore, the pressure fluctuation of the back gas can be reduced by using at least one pressure stabilizing tank 222 as described in this disclosure.

[0159] Furthermore, different V values ​​are set according to formula (6), with V = 1000 in related technology 2 and V = 2000 in this disclosure. See also Figure 13 The diagram illustrates a pressure curve provided by an embodiment of this disclosure, specifically a simplified simulation diagram using software. The dashed line represents the pressure change in related technology 2, and the dotted line represents the pressure change in this disclosure. Figure 13 As shown, the pressure curve in related technology 2 has a large oscillation amplitude and a short oscillation time; the pressure curve in this disclosure has a small oscillation amplitude and a long oscillation time.

[0160] In this embodiment, a two-stage pressure stabilizing tank 222 with volumes of 10L and 2L respectively is used to maintain the stability of the back gas pressure. The larger the sum of the volumes of the two-stage pressure stabilizing tanks 222, the smaller the fluctuation of the back gas, and the closer the first pressure value of the back gas between the wafer and the heating electrostatic chuck 211 is to the first preset pressure value. However, the larger the sum of the volumes of the two-stage pressure stabilizing tanks 222, the larger the space occupied. Therefore, the total volume of the pressure stabilizing tanks 222 can be selected according to the error range of the required first difference, as long as the selected total volume of the pressure stabilizing tanks 222 can make the first difference meet the first preset condition.

[0161] It should be noted that when the total volume of the pressure stabilizing tanks 222 is equal, the multi-stage pressure stabilizing tanks 222 provide better pressure stabilization for the back gas compared to a single pressure stabilizing tank 222. Furthermore, when there are multiple stages of pressure stabilizing tanks 222, there are no specific limitations on the volume or location of each stage.

[0162] In summary, this disclosure provides a control system 20, specifically a closed-loop flow control system. It employs a controller 221, at least one stage pressure stabilizing tank 222, and an external gauge for correction control. By monitoring the vacuum pressure (i.e., the first pressure value) closer to the heating electrostatic chuck 211, it controls the back gas flow. Simultaneously, residual back gas can be removed by an external dry pump 225. Specifically, the controller 221 controls the back gas flow rate; the two-stage pressure stabilizing tank 222 reduces fluctuations in the first vacuum gauge 223; the controller 221 implements closed-loop control of the first vacuum gauge 223, achieving automatic adjustment for different pressures; and the external dry pump 225 and the second vacuum gauge 224 ensure stable discharge of residual gas. In this way, firstly, the back gas demand can be automatically adjusted; secondly, the vacuum pressure of the back gas is stable with small fluctuations; thirdly, the flow rate and pressure of the back gas can be monitored; then, residual gas does not flow into the cavity 21; finally, a mature Pcontroller can be used, and the original pressure acquisition point in related technology 2 is changed to the first vacuum pressure gauge 223. The position of the first vacuum pressure gauge 223 is closer to the cavity 21, which can better represent the actual demand.

[0163] In another embodiment of this disclosure, see Figure 14 This illustrates a schematic diagram of the structure of a semiconductor device provided in an embodiment of this disclosure. Figure 14 As shown, the semiconductor device 30 includes the aforementioned control system 20.

[0164] The semiconductor device 30, since it includes the aforementioned control system 20, has at least the same advantages as the control system 20, which can make the pressure value of the back gas stable and have small fluctuations, and can realize closed-loop control of the first vacuum pressure gauge and automatically adjust the back gas with different pressure values.

[0165] For details not disclosed in the embodiments of this disclosure, please refer to the description of the foregoing embodiments for understanding.

[0166] The above description is merely a preferred embodiment of this disclosure and is not intended to limit the scope of protection of this disclosure.

[0167] It should be noted that, in this disclosure, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0168] The sequence numbers of the embodiments disclosed above are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0169] The methods disclosed in the several method embodiments provided in this disclosure can be arbitrarily combined without conflict to obtain new method embodiments.

[0170] The features disclosed in the several product embodiments provided in this disclosure can be combined arbitrarily without conflict to obtain new product embodiments.

[0171] The features disclosed in the several method or device embodiments provided in this disclosure can be arbitrarily combined without conflict to obtain new method or device embodiments.

[0172] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A control system, characterized in that, The control system includes a cavity and pipelines. The cavity includes a heated electrostatic chuck, on which the wafer is adsorbed. The pipelines are connected to the heated electrostatic chuck. Back gas flows through the pipelines and is introduced between the wafer and the heated electrostatic chuck. The pipelines are sequentially arranged with a controller, at least one stage of pressure stabilizing tank, and a first vacuum gauge in the direction of the back gas flowing into the cavity. The controller is connected to the first vacuum gauge. The at least one pressure stabilizing tank is used to maintain the stability of the pressure value of the back gas; The first vacuum pressure gauge is used to measure the first pressure value of the back gas between the wafer and the heated electrostatic chuck; The controller is configured to receive and adjust the flow rate of the back gas input to the at least one level pressure stabilizing tank according to the first pressure value.

2. The control system according to claim 1, characterized in that, The controller includes a first sub-controller and a second sub-controller, wherein the second sub-controller is connected to the first sub-controller and the first vacuum pressure gauge, respectively. The second sub-controller is configured to control the first sub-controller to adjust the flow rate of the back gas input to the at least one level pressure stabilizing tank based on the first difference between the first pressure value and the first preset pressure value, so that the first difference meets the first preset condition.

3. The control system according to claim 2, characterized in that, The pipeline is also equipped with a second vacuum pressure gauge and a dry pump. The dry pump is located at one end of the pipeline, and the second vacuum pressure gauge is located between the heating electrostatic chuck and the dry pump. The dry pump is used to remove the residual back gas; The second vacuum pressure gauge is used to measure a second pressure value of the back gas when the back gas is purged.

4. The control system according to claim 3, characterized in that, The pipeline is also equipped with at least one flow regulating device; The at least one flow regulating device is used to regulate the flow of the back gas.

5. The control system according to claim 4, characterized in that, The at least one flow regulating device includes a first regulating device, a second regulating device, a third regulating device, a fourth regulating device, and a fifth regulating device; The first regulating device is disposed between the gas source and the first sub-controller; the second regulating device is disposed between the first sub-controller and the at least one-stage pressure stabilizing tank; the third regulating device is disposed downstream of the first vacuum pressure gauge; the fourth regulating device is disposed between the heating electrostatic chuck and the second vacuum pressure gauge; the fifth regulating device is disposed between the third regulating device and the fourth regulating device, and also between the heating electrostatic chuck and the fourth regulating device. The gas source is used to provide the back gas.

6. The control system according to claim 5, characterized in that, When the back gas flows through the pipe between the wafer and the heated electrostatic chuck: When the first pressure value is less than the first preset pressure value and the first difference does not meet the first preset condition, the first regulating device and the second regulating device are both in the open state, and the third regulating device, the fourth regulating device and the fifth regulating device are all in the closed state; until the first difference meets the first preset condition, the at least one flow regulating device is in the closed state. When the first pressure value is greater than the first preset pressure value and the first difference does not meet the first preset condition, the third and fourth regulating devices are both in the open state, and the first, second, and fifth regulating devices are all in the closed state; until the first difference meets the first preset condition, the at least one flow regulating device is in the closed state.

7. The control system according to claim 5, characterized in that, When the back gas is discharged through the pipeline: The first regulating device, the second regulating device, and the third regulating device are all in the off state, while the fourth regulating device and the fifth regulating device are all in the on state; The at least one flow regulating device is in the off state until the second difference between the second pressure value and the second preset pressure value meets the second preset condition.

8. The control system according to claim 2, characterized in that, The control system further includes a machine tool control module, which is connected to the second sub-controller and the at least one flow regulating device, respectively, and is used to control the second sub-controller and the at least one flow regulating device.

9. The control system according to claim 1, characterized in that, The control system also includes a third vacuum pressure gauge and at least one cold pump, both of which are connected to the cavity; The third vacuum gauge is used to measure the third pressure value of the cavity; The at least one cold pump is used to adsorb the back gas remaining in the cavity.

10. The control system according to claim 2, characterized in that, The first difference is negatively correlated with the sum of the volumes of the at least one pressure stabilizing tank.

11. The control system according to any one of claims 4 to 7, characterized in that, The at least one flow regulating device is a pneumatic valve.

12. A semiconductor device, characterized in that, The semiconductor device includes a control system as described in any one of claims 1 to 11.

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