Vacuum cavity pressure control system and control method thereof

Abstract

The invention discloses a vacuum cavity pressure control system and a control method thereof. The vacuum cavity pressure control system comprises a control module, a vacuum pressure gauge and a gas flow controller, the first end of the control module is electrically connected with the vacuum pressure gauge, the second end of the control module is electrically connected with the first end of the gas flow controller, and the vacuum pressure gauge is used for detecting the cavity pressure in the vacuum cavity in real time and transmitting the cavity pressure to the control module; the control module is used for receiving the cavity pressure, comparing the cavity pressure with preset pressure and sending a flow control signal to the gas flow controller according to a comparison result; the gas flow controller is used for receiving the flow control signal and inputting or outputting gas into or out of the vacuum cavity according to the flow control signal. According to the invention, the cavity pressure in the vacuum cavity is stabilized at the preset pressure, so that the gas pressure in the vacuum cavity is always greater than that of the etching cavity, and the yield of etched wafers is improved.

Description

Technical Field

[0001] The present invention relates to the field of vacuum chamber technology, and in particular to a vacuum chamber pressure control system and a control method thereof. Background Art

[0002] During the inductively coupled plasma (ICP) etching process, the wafer needs to be transferred from the atmosphere to the vacuum / atmosphere conversion chamber, then from the vacuum / atmosphere conversion chamber to the vacuum chamber, and finally from the vacuum chamber to the etching chamber. During the process in the etching chamber, impurity particles will be generated. During continuous operation, when the processed wafer is transferred from the etching chamber to the vacuum chamber, the impurity particles in the etching chamber will flow into the vacuum chamber, polluting the vacuum chamber environment and the wafers that have not been processed, affecting the yield of the etched wafers. Summary of the invention

[0003] The present invention provides a vacuum chamber pressure control system and a control method thereof, so as to stabilize the chamber pressure in the vacuum chamber at a preset pressure, thereby making the gas pressure in the vacuum chamber always greater than that in the etching chamber, thereby improving the yield of etching wafers.

[0004] According to one aspect of the present invention, a vacuum chamber pressure control system is provided, the vacuum chamber pressure control system comprising:

[0005] Control module, vacuum pressure gauge and gas flow controller;

[0006] The first end of the control module is electrically connected to the vacuum pressure gauge, and the second end of the control module is electrically connected to the first end of the gas flow controller; the vacuum pressure gauge is arranged in the vacuum chamber, and is used to detect the cavity pressure in the vacuum chamber in real time, and transmit the cavity pressure to the control module;

[0007] The control module is used to receive the cavity pressure, compare the cavity pressure with the preset pressure, and send a flow control signal to the gas flow controller according to the comparison result;

[0008] The gas flow controller is used to receive a flow control signal and input or output gas to the vacuum chamber according to the flow control signal to adjust the chamber pressure.

[0009] Further, the control module includes: a signal processing unit and a proportional-integral-differential control unit;

[0010] The first end of the signal processing unit is electrically connected to the vacuum pressure gauge, the second end of the signal processing unit is electrically connected to the first end of the proportional-integral-differential control unit, and the signal processing unit is used to generate a pressure difference value by subtracting the cavity pressure from the preset pressure, and transmit the pressure difference value to the proportional-integral-differential control unit;

[0011] The second end of the proportional-integral-differential control unit is connected to the gas flow controller. The proportional-integral-differential control unit is used to receive the pressure difference, and generate a flow control signal based on the comparison result between the pressure difference and the preset difference, and send the flow control signal to the gas flow controller.

[0012] Further, the proportional-integral-differential control unit includes a coarse adjustment subunit and a proportional-integral-differential control subunit;

[0013] The second end of the signal processing unit is electrically connected to the first end of the coarse adjustment subunit, and the signal processing unit is used to: subtract the cavity pressure from the preset pressure to generate a pressure difference value, and transmit the pressure difference value to the coarse adjustment subunit;

[0014] The second end of the coarse adjustment subunit is connected to the first end of the gas flow controller, the third end of the coarse adjustment subunit is connected to the first end of the proportional-integral-differential control subunit, and the second end of the proportional-integral-differential control subunit is connected to the second end of the gas flow controller; the coarse adjustment subunit is used to receive the pressure difference, and compare the pressure difference corresponding to the cavity pressure with the preset difference, if the pressure difference is greater than the preset difference, send a first flow control signal to the gas flow controller; if the pressure difference is less than or equal to the preset difference, transmit the pressure difference to the proportional-integral-differential control subunit;

[0015] The proportional-integral-differential control subunit is used to perform proportional-integral-differential control processing on the pressure difference, generate a second flow control signal, and send the second flow control signal to the gas flow controller.

[0016] Furthermore, the vacuum chamber pressure control system also includes:

[0017] Alarm module; the alarm module is connected to the third terminal of the proportional-integral-differential control unit;

[0018] The PID control unit is also used for:

[0019] After the pressure difference is processed by proportional-integral-differential control for a first preset time period, if the cavity pressure in the vacuum cavity is not equal to the preset pressure, the alarm module is controlled to perform alarm processing.

[0020] Furthermore, the proportional-integral-derivative control unit is also used for:

[0021] After the pressure difference is processed by proportional-integral-differential control for a first preset time, the error ratio is determined according to the cavity pressure in the vacuum cavity and the preset pressure, and the alarm module is controlled to perform alarm processing according to the error ratio.

[0022] Furthermore, the proportional-integral-derivative control unit is also used for:

[0023] After performing proportional-integral-differential control processing on the pressure difference for a first preset time period, determining an error ratio according to the cavity pressure in the vacuum cavity and a preset pressure;

[0024] If the error ratio is less than or equal to the first preset ratio, the alarm module is controlled to perform a first alarm process;

[0025] If the error ratio is greater than the first preset ratio and less than or equal to the second preset ratio, the alarm module is controlled to perform a second alarm process;

[0026] If the error ratio is greater than the second preset ratio, the alarm module is controlled to perform a third alarm process and the gas flow controller is controlled to be turned off; wherein the first preset ratio is smaller than the second preset ratio.

[0027] Further, the control module includes a control unit and a transmission unit;

[0028] A first end of the control unit is electrically connected to the vacuum pressure gauge, a second end of the control unit is electrically connected to a first end of the gas flow controller, and a third end of the control unit is electrically connected to the transmission unit;

[0029] The transmission unit is used to transmit the preset pressure to the control unit, and the control unit is used to receive the cavity pressure and the preset pressure, compare the cavity pressure with the preset pressure, and send a flow control signal to the gas flow controller according to the comparison result.

[0030] Further, the control unit includes a programmable control device;

[0031] The transmission unit includes a host computer.

[0032] According to another aspect of the present invention, a vacuum chamber pressure control method is provided, the vacuum chamber pressure control method comprising:

[0033] The cavity pressure in the vacuum cavity is detected in real time by a vacuum pressure gauge, and the cavity pressure is transmitted to the control module;

[0034] The control module receives the cavity pressure, compares the cavity pressure with a preset pressure, and sends a flow control signal to the gas flow controller according to the comparison result;

[0035] A flow control signal is received through a gas flow controller, and gas is input or output to the vacuum chamber according to the flow control signal to adjust the chamber pressure.

[0036] Further, the cavity pressure is received by the control module, the cavity pressure is compared with a preset pressure, and a flow control signal is sent to the gas flow controller according to the comparison result, including:

[0037] The pressure of the cavity is subtracted from the preset pressure by a signal processing unit in the control module to generate a pressure difference value, and the pressure difference value is transmitted to a proportional-integral-differential control unit;

[0038] The pressure difference is received by the proportional-integral-differential control unit in the control module, and a flow control signal is generated according to the comparison result between the pressure difference and the preset difference, and the flow control signal is sent to the gas flow controller.

[0039] The vacuum chamber pressure control system provided by the embodiment of the present invention includes a control module, a vacuum pressure gauge and a gas flow controller. The vacuum pressure gauge detects the chamber pressure in the vacuum chamber in real time and transmits the chamber pressure to the control module. The control module receives the chamber pressure, compares the chamber pressure with a preset pressure, and sends a flow control signal to the gas flow controller according to the comparison result. The gas flow controller receives the flow control signal and inputs or outputs the gas flow to the vacuum chamber according to the flow control signal, so that the chamber pressure in the vacuum chamber is stabilized at the preset pressure, thereby making the gas pressure in the vacuum chamber always greater than the etching chamber, thereby avoiding impurity particles from moving from the etching chamber to the vacuum chamber to contaminate wafers that have not been processed, thereby improving the yield of etched wafers.

[0040] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0042] Figure 1 is a structural schematic diagram of a vacuum chamber pressure control system provided according to an embodiment of the present invention;

[0043] Figure 2 is a structural schematic diagram of another vacuum chamber pressure control system provided according to an embodiment of the present invention;

[0044] Figure 3 is a structural schematic diagram of another vacuum chamber pressure control system provided according to an embodiment of the present invention;

[0045] Figure 4 is a structural schematic diagram of another vacuum chamber pressure control system provided according to an embodiment of the present invention;

[0046] Figure 5is a structural schematic diagram of another vacuum chamber pressure control system provided according to an embodiment of the present invention;

[0047] Figure 6 is a flow chart of a vacuum chamber pressure control method provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0049] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0050] The embodiment of the present invention provides a vacuum chamber pressure control system. Figure 1 is a schematic diagram of a vacuum chamber pressure control system according to an embodiment of the present invention, with reference to Figure 1 , the vacuum chamber pressure control system includes:

[0051] Control module 1, vacuum pressure gauge 2 and gas flow controller 3;

[0052] The first end of the control module 1 is electrically connected to the vacuum pressure gauge 2, and the second end of the control module 1 is electrically connected to the first end of the gas flow controller 3; the vacuum pressure gauge 2 is arranged in the vacuum chamber 4, and is used to detect the cavity pressure in the vacuum chamber 4 in real time, and transmit the cavity pressure to the control module 1;

[0053] The control module 1 is used to receive the cavity pressure, compare the cavity pressure with the preset pressure, and send a flow control signal to the gas flow controller 3 according to the comparison result;

[0054] The gas flow controller 3 is used to receive a flow control signal and input or output gas to the vacuum chamber 4 according to the flow control signal to adjust the chamber pressure.

[0055] Specifically, after the vacuum chamber pressure control system starts working, the staff can set the preset pressure of the vacuum chamber 4 in the control module 1 according to actual needs, so that the gas pressure in the vacuum chamber 4 is always greater than the etching chamber. At the same time, the vacuum pressure gauge 2 detects the cavity pressure in the vacuum chamber 4 in real time, and transmits the real-time detected cavity pressure to the control module 1. The control module 1 compares the cavity pressure with the preset pressure. For example, the cavity pressure can be subtracted from the preset pressure to determine the pressure difference, and the pressure difference is processed by proportional-integral-differential control to generate a flow control signal, and send the flow control signal to the gas flow controller. The gas flow controller 3 inputs or outputs gas to the vacuum chamber 4 according to the received flow control signal, so that the cavity pressure in the vacuum chamber 4 is stabilized at the preset pressure, so that the gas pressure in the vacuum chamber 4 is always greater than the etching chamber. For example, the preset pressure is 40mtorr.

[0056] The vacuum chamber pressure control system provided by the embodiment of the present invention includes a control module 1, a vacuum pressure gauge 2 and a gas flow controller 3. The vacuum pressure gauge 2 detects the chamber pressure in the vacuum chamber 4 in real time, and transmits the chamber pressure to the control module 1. The control module 1 receives the chamber pressure, compares the chamber pressure with a preset pressure, and sends a flow control signal to the gas flow controller 3 according to the comparison result. The gas flow controller 3 receives the flow control signal, and inputs or outputs the gas flow to the vacuum chamber 4 according to the flow control signal, so that the chamber pressure in the vacuum chamber 4 is stabilized at the preset pressure, thereby making the gas pressure in the vacuum chamber 4 always greater than that in the etching chamber, thereby avoiding impurity particles from moving from the etching chamber to the vacuum chamber 4 to contaminate wafers that have not been processed, thereby improving the yield of etched wafers.

[0057] Furthermore, Figure 2 is a schematic diagram of the structure of another vacuum chamber pressure control system provided according to an embodiment of the present invention, with reference to Figure 2 , the control module includes: a signal processing unit 11 and a proportional-integral-differential control unit 12;

[0058] The first end of the signal processing unit 11 is electrically connected to the vacuum pressure gauge 2, and the second end of the signal processing unit 11 is electrically connected to the first end of the proportional-integral-differential control unit 12. The signal processing unit 11 is used to make a difference between the cavity pressure and the preset pressure to generate a pressure difference value, and transmit the pressure difference value to the proportional-integral-differential control unit 12;

[0059] The second end of the proportional-integral-differential control unit 12 is connected to the gas flow controller 3. The proportional-integral-differential control unit 12 is used to receive the pressure difference, and generate a flow control signal based on the comparison result between the pressure difference and the preset difference, and send the flow control signal to the gas flow controller 3.

[0060] Specifically, the signal processing unit subtracts the received cavity pressure from the preset pressure to generate a pressure difference, and transmits the pressure difference to the proportional-integral-differential control unit 12. The proportional-integral-differential control unit 12 can generate a flow control signal according to the size of the pressure difference. For example, if the pressure difference is greater than the preset difference, the cavity pressure is adjusted according to a fixed first threshold value, and a flow control signal is sent to the gas flow controller; if the pressure difference is less than the preset difference, the pressure difference is proportionally-integral-differential controlled, and a flow control signal is sent to the gas flow controller 3 to change the cavity pressure.

[0061] Furthermore, Figure 3 is a schematic diagram of a structure of another vacuum chamber pressure control system provided according to an embodiment of the present invention, with reference to Figure 3 , the proportional-integral-differential control unit includes a coarse adjustment subunit 121 and a proportional-integral-differential control subunit 122;

[0062] The second end of the signal processing unit 11 is electrically connected to the first end of the coarse adjustment subunit 121, and the signal processing unit 11 is used to: subtract the cavity pressure from the preset pressure to generate a pressure difference value, and transmit the pressure difference value to the coarse adjustment subunit 121;

[0063] The second end of the coarse adjustment subunit 121 is connected to the first end of the gas flow controller 3, the third end of the coarse adjustment subunit 121 is connected to the first end of the proportional-integral-differential control subunit 122, and the second end of the proportional-integral-differential control subunit 122 is connected to the second end of the gas flow controller 3; the coarse adjustment subunit 121 is used to receive the pressure difference, and compare the pressure difference corresponding to the cavity pressure with the preset difference, if the pressure difference is greater than the preset difference, then send a first flow control signal to the gas flow controller 3; if the pressure difference is less than or equal to the preset difference, then transmit the pressure difference to the proportional-integral-differential control subunit 122;

[0064] The proportional-integral-differential control subunit 122 is used to perform proportional-integral-differential control processing on the pressure difference, generate a second flow control signal, and send the second flow control signal to the gas flow controller 3.

[0065] Specifically, the coarse adjustment subunit 121 compares the pressure difference value transmitted by the received signal processing unit 11 with the preset difference value. If the pressure difference value is greater than the preset difference value, it means that the cavity pressure is greatly different from the preset pressure. At this time, a first flow control signal needs to be sent to the gas flow controller 3. The gas flow controller 3 performs coarse adjustment on the cavity pressure according to a fixed threshold value to quickly reduce the gap between the cavity pressure and the preset pressure. When the pressure difference value is less than the preset difference value, the pressure difference value is transmitted to the proportional-integral-differential control subunit 122, indicating that the cavity pressure is less different from the preset pressure at this time, and the cavity pressure can be fine-tuned. The proportional-integral-differential control subunit 122 performs proportional-integral-differential control processing on the received pressure difference value, generates a second flow control signal, and sends the second flow control signal to the gas flow controller 3. The gas flow controller 3 fine-adjusts the cavity pressure according to the fixed threshold value until the fine-tuning of the cavity pressure is completed. Among them, the preset difference value can be set according to actual conditions, and the embodiment of the present invention does not limit this.

[0066] Furthermore, Figure 4 is a schematic diagram of a structure of another vacuum chamber pressure control system provided according to an embodiment of the present invention, with reference to Figure 4 , the vacuum chamber pressure control system also includes:

[0067] Alarm module 5; the alarm module 5 is connected to the third terminal of the proportional-integral-differential control unit 12;

[0068] The proportional-integral-derivative control unit 12 is also used for:

[0069] After the pressure difference is processed by proportional-integral-differential control for a first preset time period, if the cavity pressure in the vacuum cavity 4 is not equal to the preset pressure, the alarm module 5 is controlled to perform an alarm process.

[0070] Specifically, if the cavity pressure in the vacuum cavity 4 cannot be equal to the preset pressure after the pressure difference is processed by proportional-integral-differential control for the first preset time, it means that the vacuum cavity 4 or the vacuum cavity pressure control system is abnormal. At this time, an alarm signal needs to be sent to the control module 5 to control the alarm module 5 to perform alarm processing to remind the on-site staff that the vacuum cavity 4 or the vacuum cavity pressure control system is abnormal, so as to perform fault detection and maintenance in time. Exemplarily, if the cavity pressure in the vacuum cavity 4 is less than the preset pressure after the pressure difference is processed by proportional-integral-differential control for the first preset time, it may be that the vacuum cavity 4 has a side leak. The on-site staff needs to close the vacuum cavity 4, perform a leak detection on the vacuum cavity 4, and control the vacuum cavity pressure control system to stop working; if the cavity pressure in the vacuum cavity 4 is greater than the preset pressure after the pressure difference is processed by proportional-integral-differential control, it may be that the gas flow controller 3 is damaged. The on-site staff needs to close the vacuum cavity 4 and control the vacuum cavity pressure control system to stop working.

[0071] Furthermore, the proportional-integral-derivative control unit is also used for:

[0072] After the pressure difference is processed by proportional-integral-differential control for a first preset time, the error ratio is determined according to the cavity pressure in the vacuum cavity and the preset pressure, and the alarm module is controlled to perform alarm processing according to the error ratio.

[0073] The error ratio can be understood as the percentage of the difference between the cavity pressure in the vacuum cavity and the preset pressure to the preset pressure.

[0074] Specifically, if the pressure difference is subjected to proportional-integral-differential control processing for a first preset period of time, the error ratio is determined based on the cavity pressure in the vacuum chamber and the preset pressure; if the error ratio is less than or equal to the first preset ratio, the alarm module is controlled to perform a first alarm processing; if the error ratio is greater than the first preset ratio and less than or equal to the second preset ratio, the alarm module is controlled to perform a second alarm processing; if the error ratio is greater than the second preset ratio, the alarm module is controlled to perform a second alarm processing and the gas flow controller is controlled to be closed.

[0075] Furthermore, the proportional-integral-derivative control unit is also used for:

[0076] After performing proportional-integral-differential control processing on the pressure difference for a first preset time period, determining an error ratio according to the cavity pressure in the vacuum cavity and a preset pressure;

[0077] If the error ratio is less than or equal to the first preset ratio, the alarm module is controlled to perform a first alarm process;

[0078] If the error ratio is greater than the first preset ratio and less than or equal to the second preset ratio, the alarm module is controlled to perform a second alarm process;

[0079] If the error ratio is greater than the second preset ratio, the alarm module is controlled to perform a third alarm process and the gas flow controller is controlled to be turned off; wherein the first preset ratio is smaller than the second preset ratio.

[0080] Specifically, if the error ratio is less than or equal to the first preset ratio, it means that after the first preset time, there is a small gap between the cavity pressure in the vacuum chamber and the preset pressure, and the cavity pressure in the vacuum chamber cannot be controlled to be stable at the preset pressure. At this time, it means that there is a small deviation in the vacuum chamber or the vacuum chamber pressure control system. It is only necessary to send a prompt alarm signal to the control module, and the control alarm module performs the first alarm processing to remind on-site staff that there is a small deviation in the vacuum chamber or the vacuum chamber pressure control system, so as to perform fault detection and maintenance when convenient.

[0081] If the error ratio is greater than the first preset ratio and less than or equal to the second preset ratio, it means that after the first preset time, there is a certain gap between the cavity pressure in the vacuum chamber and the preset pressure, and the cavity pressure in the vacuum chamber cannot be controlled to be stable at the preset pressure. At this time, it means that there is a certain deviation in the vacuum chamber or the vacuum chamber pressure control system, and a warning alarm signal needs to be sent to the control module, and the control alarm module performs the second alarm processing to remind on-site staff that there is a certain deviation in the vacuum chamber or the vacuum chamber pressure control system, and to perform fault detection and maintenance in time.

[0082] If the error ratio is greater than the second preset ratio, it means that after the first preset time, there is a large gap between the cavity pressure in the vacuum chamber and the preset pressure, and the cavity pressure in the vacuum chamber cannot be controlled to be stable at the preset pressure. At this time, it means that there is a large deviation in the vacuum chamber or the vacuum chamber pressure control system, and it is necessary to send a shutdown alarm signal to the control module, and the control alarm module performs the third alarm processing to remind on-site staff that there is a large deviation in the vacuum chamber or the vacuum chamber pressure control system, and it is necessary to immediately control the vacuum chamber to close and perform fault detection and maintenance, and at the same time control the gas flow controller to close.

[0083] Furthermore, Figure 5 is a schematic diagram of the structure of another vacuum chamber pressure control system provided according to an embodiment of the present invention, with reference to Figure 5 , the control module includes a control unit 11 and a transmission unit 12;

[0084] A first end of the control unit 11 is electrically connected to the vacuum pressure gauge 2, a second end of the control unit 11 is electrically connected to a first end of the gas flow controller 3, and a third end of the control unit 11 is electrically connected to the transmission unit 12;

[0085] The transmission unit 12 is used to transmit the preset pressure to the control unit 11, and the control unit 11 is used to receive the cavity pressure and the preset pressure, compare the cavity pressure with the preset pressure, and send a flow control signal to the gas flow controller 3 according to the comparison result.

[0086] Specifically, after the vacuum chamber pressure control system starts working, the staff can set the preset pressure of the vacuum chamber 4 in the transmission unit 12 according to actual needs, so that the gas pressure in the vacuum chamber 4 is always greater than the etching chamber, and the transmission unit 12 transmits the preset pressure of the vacuum chamber 4 to the control unit 11. At the same time, the vacuum pressure gauge 2 detects the cavity pressure in the vacuum chamber 4 in real time, and transmits the real-time detected cavity pressure to the control unit 11. The control unit 11 subtracts the cavity pressure from the preset pressure to determine the pressure difference, and sends a flow control signal to the gas flow controller according to the comparison result of the pressure difference and the preset difference. Finally, the gas flow controller 3 outputs the gas flow to the vacuum chamber 4 according to the received flow control signal, so that the cavity pressure in the vacuum chamber 4 is stabilized at the preset pressure, thereby making the gas pressure in the vacuum chamber 4 always greater than the etching chamber.

[0087] Further, the transmission unit includes a programmable control device;

[0088] The transmission unit includes a host computer.

[0089] The embodiment of the present invention provides a vacuum chamber pressure control method. Figure 6 is a flow chart of a vacuum chamber pressure control method provided according to an embodiment of the present invention, with reference to Figure 6 , control methods include:

[0090] S110, detecting the cavity pressure in the vacuum cavity in real time through a vacuum pressure gauge, and transmitting the cavity pressure to a control module.

[0091] S120, receiving the cavity pressure through the control module, comparing the cavity pressure with a preset pressure, and sending a flow control signal to the gas flow controller according to the comparison result;

[0092] S130, receiving a flow control signal through a gas flow controller, and inputting or outputting gas to the vacuum chamber according to the flow control signal to adjust the chamber pressure.

[0093] The vacuum chamber pressure control method corresponding to the vacuum chamber pressure control system provided in the embodiment of the present invention detects the chamber pressure in the vacuum chamber in real time through a vacuum pressure gauge, and transmits the chamber pressure to a control module. The control module receives the chamber pressure, compares the chamber pressure with a preset pressure, and sends a flow control signal to a gas flow controller according to the comparison result. The gas flow controller receives the flow control signal, and inputs or outputs gas to the vacuum chamber according to the flow control signal, so that the chamber pressure in the vacuum chamber is stabilized at the preset pressure, thereby making the gas pressure in the vacuum chamber always greater than the etching chamber, thereby avoiding impurity particles from moving from the etching chamber to the vacuum chamber to contaminate wafers that have not been processed, thereby improving the yield of etched wafers.

[0094] Further, the cavity pressure is received by the control module, the cavity pressure is compared with a preset pressure, and a flow control signal is sent to the gas flow controller according to the comparison result, including:

[0095] The pressure of the cavity is subtracted from the preset pressure by the signal processing unit in the control module to generate a pressure difference value, and the pressure difference value is transmitted to the proportional-integral-differential control unit in the control module;

[0096] The pressure difference is received by a proportional-integral-differential control unit in the control module, and the flow control signal is generated according to the comparison result between the pressure difference and the preset difference, and the flow control signal is sent to the gas flow controller.

[0097] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0098] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A vacuum chamber pressure control system, characterized in that: include: Control module, vacuum pressure gauge and gas flow controller; The first end of the control module is electrically connected to the vacuum pressure gauge, and the second end of the control module is electrically connected to the first end of the gas flow controller; the vacuum pressure gauge is arranged in the vacuum chamber, and is used to detect the chamber pressure in the vacuum chamber in real time, and transmit the chamber pressure to the control module; The control module is used to receive the cavity pressure, compare the cavity pressure with a preset pressure, and send a flow control signal to the gas flow controller according to the comparison result; The gas flow controller is used to receive the flow control signal and input or output gas to the vacuum chamber according to the flow control signal to adjust the chamber pressure.

2. The vacuum chamber pressure control system according to claim 1, characterized in that: The control module includes: a signal processing unit and a proportional-integral-differential control unit; The first end of the signal processing unit is electrically connected to the vacuum pressure gauge, and the second end of the signal processing unit is electrically connected to the first end of the proportional-integral-differential control unit. The signal processing unit is used to generate a pressure difference value by subtracting the cavity pressure from the preset pressure, and transmit the pressure difference value to the proportional-integral-differential control unit; The second end of the proportional-integral-differential control unit is connected to the gas flow controller, and the proportional-integral-differential control unit is used to receive the pressure difference, and generate the flow control signal according to the comparison result between the pressure difference and the preset difference, and send the flow control signal to the gas flow controller.

3. The vacuum chamber pressure control system according to claim 2, characterized in that: The proportional-integral-differential control unit includes a coarse adjustment subunit and a proportional-integral-differential control subunit; The second end of the signal processing unit is electrically connected to the first end of the coarse adjustment subunit, and the signal processing unit is used to: subtract the cavity pressure from the preset pressure to generate the pressure difference value, and transmit the pressure difference value to the coarse adjustment subunit; The second end of the coarse adjustment subunit is connected to the first end of the gas flow controller, the third end of the coarse adjustment subunit is connected to the first end of the proportional-integral-differential control subunit, and the second end of the proportional-integral-differential control subunit is connected to the second end of the gas flow controller; the coarse adjustment subunit is used to receive the pressure difference, and compare the pressure difference corresponding to the cavity pressure with the preset difference, and if the pressure difference is greater than the preset difference, send a first flow control signal to the gas flow controller; If the pressure difference is less than or equal to the preset difference, transmitting the pressure difference to the proportional-integral-derivative control subunit; The proportional-integral-differential control subunit is used to perform proportional-integral-differential control processing on the pressure difference, generate a second flow control signal, and send the second flow control signal to the gas flow controller.

4. The vacuum chamber pressure control system according to claim 2, characterized in that: Also includes: An alarm module; the alarm module is connected to the third terminal of the proportional-integral-differential control unit; The proportional-integral-derivative control unit is also used for: After the pressure difference is subjected to the proportional-integral-differential control process for a first preset time period, if the cavity pressure in the vacuum cavity is not equal to the preset pressure, the alarm module is controlled to perform an alarm process.

5. The vacuum chamber pressure control system according to claim 4, characterized in that: The proportional-integral-derivative control unit is also used for: After the pressure difference is subjected to the proportional-integral-differential control process for a first preset time period, an error ratio is determined according to the cavity pressure in the vacuum cavity and the preset pressure, and the alarm module is controlled to perform alarm processing according to the error ratio.

6. The vacuum chamber pressure control system according to claim 5, characterized in that: The proportional-integral-derivative control unit is also used for: After the pressure difference is subjected to the proportional-integral-differential control process for a first preset time period, an error ratio is determined according to the cavity pressure in the vacuum cavity and the preset pressure; If the error ratio is less than or equal to a first preset ratio, controlling the alarm module to perform a first alarm process; If the error ratio is greater than the first preset ratio and less than or equal to the second preset ratio, controlling the alarm module to perform a second alarm process; If the error ratio is greater than the second preset ratio, the alarm module is controlled to perform a third alarm process and the gas flow controller is controlled to be turned off; wherein the first preset ratio is smaller than the second preset ratio.

7. The vacuum chamber pressure control system according to claim 1, characterized in that: The control module includes a control unit and a transmission unit; The first end of the control unit is electrically connected to the vacuum pressure gauge, the second end of the control unit is electrically connected to the first end of the gas flow controller, and the third end of the control unit is electrically connected to the transmission unit; The transmission unit is used to transmit the preset pressure to the control unit, and the control unit is used to receive the cavity pressure and the preset pressure, compare the cavity pressure with the preset pressure, and send a flow control signal to the gas flow controller according to the comparison result.

8. The vacuum chamber pressure control system according to claim 7, characterized in that: The control unit includes a programmable control device; The transmission unit includes a host computer.

9. A vacuum chamber pressure control method, characterized in that: include: The vacuum pressure gauge detects the cavity pressure in the vacuum cavity in real time, and transmits the cavity pressure to the control module; Receiving the cavity pressure through a control module, comparing the cavity pressure with a preset pressure, and sending a flow control signal to a gas flow controller according to the comparison result; The gas flow controller receives the flow control signal and inputs or outputs gas to the vacuum chamber according to the flow control signal to adjust the chamber pressure.

10. The vacuum chamber pressure control method according to claim 9, characterized in that: Receiving the cavity pressure through a control module, comparing the cavity pressure with a preset pressure, and sending a flow control signal to a gas flow controller according to the comparison result, including: Subtracting the cavity pressure from the preset pressure through a signal processing unit in the control module to generate a pressure difference value, and transmitting the pressure difference value to a proportional-integral-differential control unit in the control module; The pressure difference is received by the proportional-integral-differential control unit in the control module, and the flow control signal is generated according to the comparison result between the pressure difference and the preset difference, and the flow control signal is sent to the gas flow controller.

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