Interlock circuit and semiconductor process equipment

Abstract

The application provides an interlocking circuit and a semiconductor process equipment, the interlocking circuit comprises a first control switch and a second control switch, wherein the first control switch is used for disconnecting a pressure relief valve control signal output by an industrial computer when an electrostatic chucking voltage of an electrostatic chuck is less than a preset voltage threshold, and connecting an air inlet valve control signal output by the industrial computer to a control end of the second control switch; the second control switch is used for outputting a closing signal to an air inlet valve of a back blowing pipeline and outputting an opening signal to a pressure relief valve of the back blowing pipeline when the control end of the second control switch is connected with the air inlet valve control signal. The application realizes local hardware interlocking through the interlocking circuit, can avoid damage of a wafer caused by wafer drift or flying piece collision, and ensures safety of a semiconductor process.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor process equipment, in particular to an interlocking circuit for an electrostatic chuck back-blow pipeline and a semiconductor process equipment. BACKGROUND

[0002] In a semiconductor process equipment such as an etching machine, a wafer is usually supported by an electrostatic chuck (ESC). Specifically, a direct current electrode is embedded in a dielectric layer of the electrostatic chuck, and the direct current electrode is connected to a high-voltage direct current power supply to polarize the surface charge of the dielectric layer, thereby fixing the wafer by electrostatic adsorption. At the same time, helium gas is introduced between the wafer and the electrostatic chuck to make the wafer obtain more uniform dynamic constant temperature. At this time, it is necessary to ensure that the coulomb force of electrostatic adsorption is greater than the helium gas pressure on the back surface of the wafer, otherwise wafer drift or wafer damage will occur.

[0003] However, the existing semiconductor process equipment often cannot timely detect abnormal electrostatic adsorption voltage, and continues to introduce helium gas to the back surface of the wafer when the electrostatic chuck cannot effectively fix the wafer, resulting in wafer drift or wafer damage under the action of helium gas pressure, thereby causing wafer damage and poor safety.

[0004] Therefore, how to provide a semiconductor process equipment capable of timely detecting wafer adsorption voltage abnormality and ensuring the safety of semiconductor process has become a technical problem to be solved in the field. SUMMARY

[0005] The present application aims to provide an interlocking circuit for an electrostatic chuck back-blow pipeline and a semiconductor process equipment, which can timely detect wafer adsorption voltage abnormality and ensure the safety of semiconductor process.

[0006] To achieve the above-mentioned purpose, as one aspect of the present application, an interlocking circuit for an electrostatic chuck back-blow pipeline is provided, comprising a first control switch and a second control switch, wherein

[0007] The first control switch is used to disconnect the pressure relief valve control signal output by the industrial computer when the electrostatic adsorption voltage of the electrostatic chuck is less than a preset voltage threshold, and to connect the gas inlet valve control signal output by the industrial computer to the control end of the second control switch.

[0008] The second control switch is used to output a closing signal to the gas inlet valve of the back-blow pipeline and an opening signal to the pressure relief valve of the back-blow pipeline when the control end thereof is connected to the gas inlet valve control signal.

[0009] Optionally, when the control end of the second control switch is in communication with the intake valve control signal, if the intake valve control signal is open, the second control switch is triggered to output a high resistance state signal to the intake valve and a high level signal to the pressure relief valve; or

[0010] if the intake valve control signal is closed, the second control switch is not triggered to output a high resistance state signal to the intake valve and the pressure relief valve, respectively.

[0011] Optionally, the first control switch is further configured to, when the electrostatic adsorption voltage detected by the voltage sensor is greater than or equal to the preset voltage threshold, connect the intake valve control signal and the pressure relief valve control signal to the intake valve and the pressure relief valve, respectively.

[0012] Optionally, the intake valve control signal and the pressure relief valve control signal are connected to the intake valve and the pressure relief valve, respectively, via the second control switch.

[0013] Optionally, the first control switch is a double-pole double-throw relay, a first fixed end of the first control switch is electrically connected to an intake valve control signal output port of the industrial computer, and a second fixed end of the first control switch is electrically connected to a pressure relief valve control signal output port of the industrial computer.

[0014] A first normally open contact corresponding to the first fixed end is electrically connected to the control end of the second control switch, and a second normally open contact corresponding to the second fixed end is suspended.

[0015] A first normally closed contact corresponding to the first fixed end and a second normally closed contact corresponding to the second fixed end are connected to a signal input end of the second control switch, respectively.

[0016] Optionally, the second control switch is a double-pole double-throw relay, a third fixed end of the second control switch is electrically connected to the intake valve, and a fourth fixed end of the second control switch is electrically connected to the pressure relief valve.

[0017] A third normally open contact corresponding to the third fixed end is suspended, and a fourth normally open contact corresponding to the fourth fixed end is connected to a high level.

[0018] A third normally closed contact corresponding to the third fixed end and a fourth normally closed contact corresponding to the fourth fixed end are connected to the signal input end of the second control switch, and are electrically connected to the first normally closed contact and the second normally closed contact, respectively.

[0019] Optionally, a first end of the electromagnetic winding of the first control switch is connected to a high level, and a second end of the electromagnetic winding of the first control switch is grounded; a first end of the electromagnetic winding of the second control switch is connected to the first normally open contact corresponding to the first fixed terminal, and a second end of the electromagnetic winding of the second control switch is grounded.

[0020] Optionally, the interlocking circuit further comprises an input terminal, an output terminal and a reference voltage terminal, the first fixed terminal and the second fixed terminal are connected to the input terminal, and the third fixed terminal and the fourth fixed terminal are connected to the output terminal.

[0021] The second end of the electromagnetic winding of the first control switch and the second end of the electromagnetic winding of the second control switch are both grounded through the reference voltage terminal, and the first end of the electromagnetic winding of the first control switch and the fourth normally open contact are both connected to a high level through the reference voltage terminal.

[0022] As a second aspect of the present application, a semiconductor process equipment is provided, comprising a cavity, an electrostatic chuck, a back-blowing pipeline, a controller, a voltage sensor and the interlocking circuit described above, the electrostatic chuck is arranged in the cavity and is used to adsorb a wafer by electrostatic adsorption, the voltage sensor is used to detect the electrostatic adsorption voltage of the electrostatic chuck, the back-blowing pipeline is provided with an air inlet valve and a pressure relief valve, and the interlocking circuit is used to output switching signals to the air inlet valve and the pressure relief valve according to the electrostatic adsorption voltage of the electrostatic chuck detected by the voltage sensor.

[0023] In the semiconductor process equipment provided by the present application, when the electrostatic adsorption force of the electrostatic chuck is sufficient to fix the wafer (i.e. when the electrostatic adsorption voltage is greater than or equal to the preset voltage threshold), the interlocking circuit can normally transmit the control signals of the industrial computer to the air inlet valve and the pressure relief valve to open or close the pressure relief valve, and when the electrostatic adsorption force of the electrostatic chuck is too small (i.e. when the electrostatic adsorption voltage is less than the preset voltage threshold), the air inlet valve is controlled to be closed and the pressure relief valve is controlled to be opened, so that the local hardware interlocking is realized by the voltage sensor and the interlocking circuit of the semiconductor process equipment. Even if the industrial computer misjudges and sends an incorrect control signal due to a failure of the power supply assembly, the back-blowing pipeline will not supply air when the electrostatic adsorption force of the electrostatic chuck is too small, thereby avoiding damage to the wafer caused by wafer drift or flying piece collision, and ensuring the safety of the semiconductor process and the product yield of the wafer.

[0024] Moreover, in the present application, the interlocking circuit is directly used to realize the interlocking cut-off control as a hardware, and the original control signal of the industrial computer can be reused to achieve the necessary process of stopping air supply + pressure relief, thereby avoiding the development cost of redesigning the software process of the industrial computer. Directly adding a device can realize the corresponding function, and the adaptability of the semiconductor process equipment to different machines is improved. BRIEF DESCRIPTION OF DRAWINGS

[0025] The accompanying drawings are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and are

[0026] Figure 1 is a structural schematic diagram of a semiconductor process equipment provided by an embodiment of the application;

[0027] Figure 2 is a structural schematic diagram of an interlocking circuit provided by an embodiment of the application;

[0028] Figure 3 is a functional logic schematic diagram of an interlocking circuit provided by an embodiment of the application.

[0029] Legend of reference signs:

[0030] Cavity 110;

[0031] Electrostatic chuck 120;

[0032] Suction electrode 121;

[0033] Back-blowing pipeline 210;

[0034] Gas inlet valve 220;

[0035] Pressure relief valve 230;

[0036] Voltage sensor 300;

[0037] Interlocking circuit 400;

[0038] First control switch 410;

[0039] Second control switch 420;

[0040] Controller 500;

[0041] Power supply assembly 600;

[0042] High-voltage direct-current power supply 610;

[0043] Direct-current filter box 620;

[0044] Solenoid valve group 700;

[0045] Wafer 10. DETAILED DESCRIPTION

[0046] The specific embodiments of the application will be described below in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely intended to illustrate and explain the application, and are not intended to limit the application.

[0047] To solve the above-mentioned technical problems, the present invention provides an interlocking circuit for the back-blowing pipeline of an electrostatic chuck, applicable to the back-blowing pipeline of an electrostatic chuck in semiconductor process equipment, such as... Figure 1 As shown, the semiconductor process equipment includes a cavity 110, an electrostatic chuck 120, and a back-blowing pipeline 210. The electrostatic chuck 120 is disposed in the cavity 110 and is used to adsorb the wafer 10 by electrostatic adsorption based on the received electrostatic adsorption voltage. The back-blowing pipeline 210 is equipped with an inlet valve 220 and a pressure relief valve 230. Figure 2 As shown, the interlock circuit 400 includes a first control switch 410 and a second control switch 420, wherein...

[0048] The first control switch 410 is used to disconnect the pressure relief valve control signal output by the industrial computer (controller 500) when the electrostatic adsorption voltage of the electrostatic chuck 120 is less than a preset voltage threshold, and connect the intake valve control signal output by the industrial computer to the control terminal of the second control switch 420; wherein, the electrostatic adsorption voltage can be detected, for example, by a voltage sensor 300 electrically connected to the adsorption electrode 121 of the electrostatic chuck 120.

[0049] The second control switch 420 is used to output a closing signal to the intake valve 220 of the back-blowing pipeline and an opening signal to the pressure relief valve 230 of the back-blowing pipeline when its control terminal is connected to the intake valve control signal.

[0050] In the interlock circuit provided by the present invention, the first control switch 410 can disconnect the pressure relief valve control signal output by the industrial control computer when the electrostatic adsorption voltage is less than a preset voltage threshold. According to the pressure relief control signal issued by the industrial control computer, the first control switch 410 connects the air intake valve control signal output by the industrial control computer to the control terminal of the second control switch 420. When the second control switch 420 is connected to the air intake valve control signal at its control terminal, it can output a closing signal to the air intake valve 220 of the back-blowing pipeline and an opening signal to the pressure relief valve 230 of the back-blowing pipeline. Thus, when the electrostatic adsorption voltage is lower than the preset voltage threshold, the first control switch 410 controls the air intake valve 220 to close and the pressure relief valve 230 to open.

[0051] That is, when the electrostatic chucking force of the electrostatic chuck 120 is sufficient to fix the wafer 10 (i.e., when the electrostatic chucking voltage is greater than or equal to the preset voltage threshold), the intake valve 220 and the pressure relief valve 230 will be normally transmitted to the control signal of the industrial computer to open or close the pressure relief valve, and when the electrostatic chucking force of the electrostatic chuck 120 is too small (i.e., when the electrostatic chucking voltage is less than the preset voltage threshold), the intake valve 220 is controlled to be closed and the pressure relief valve 230 is controlled to be opened, so that the local hardware interlocking is realized through the voltage sensor 300 and the interlocking circuit 400 of the semiconductor process equipment, even if the industrial computer misjudges and sends an error control signal due to failure of the power supply assembly 600 and other reasons, the back blow pipeline 210 will not supply gas when the electrostatic chucking force of the electrostatic chuck 120 is too small, thereby avoiding damage to the wafer 10 due to drift or flying piece collision, and ensuring the safety of the semiconductor process and the product yield of the wafer 10.

[0052] Moreover, the interlocking circuit 400 is directly used in the present application to realize the interlocking cut-off control, and the original control signal of the industrial computer can be reused to achieve the necessary process of stopping gas supply + pressure relief, thereby avoiding the development cost of redesigning the software process of the industrial computer, and directly adding the device can realize the corresponding function, thereby improving the adaptability of the semiconductor process equipment to different machines.

[0053] As an optional embodiment of the present application, as shown in Figure 1 The power supply assembly 600 is used to provide the two adsorption electrodes 121 with electrostatic chucking voltages of opposite polarities.

[0054] The wafer with a specification of 12 inches (the radius r is 0.15 m), the helium gas pressure P on the back surface is 20 Torr, the vacuum dielectric constant ε0 is 8.85e -12 F / m, the relative dielectric constant ε of aluminum oxide is about 10, the thickness d of the electrostatic chuck is 0.2 mm, and the helium gas flow pressure received by the wafer is:

[0055] F1=πr 2 P=187N;

[0056] In order to ensure that the electrostatic chucking force is greater than the helium gas flow pressure, the electrostatic chucking voltage v needs to satisfy:

[0057]

[0058] It can be calculated that the electrostatic chucking voltage v needs to satisfy v<1600V, that is, the preset voltage threshold can be 1600V.

[0059] As an optional embodiment of the present application, as shown in Figure 1As shown, the pressure relief valve 230 is used to selectively connect the back blow pipeline 210 with the vacuum pump 240 (Pump) to release the temperature control gas in the back blow pipeline 210.

[0060] As an optional embodiment of the present application, when the control end of the second control switch 420 is connected with the intake valve control signal, if the intake valve control signal is open, the second control switch 420 is triggered to output a high resistance state signal to the intake valve 220 and a high level signal to the pressure relief valve 230 (i.e. control the intake valve 220 to close and control the pressure relief valve 230 to open, and release the temperature control gas in the back blow pipeline 210); or

[0061] If the intake valve control signal is closed, the second control switch 420 is not triggered, and a high resistance state signal is output to the intake valve 220 and the pressure relief valve 230 respectively (i.e. control the intake valve 220 and the pressure relief valve 230 to close together, and stop inputting the temperature control gas into the chamber).

[0062] As an optional embodiment of the present application, as shown, Figure 2 The intake valve control signal and the pressure relief valve control signal are connected to the intake valve 220 and the pressure relief valve 230 respectively through the second control switch 420.

[0063] Specifically, as shown, Figure 2 The first control switch 410 is a double-pole double-throw relay, the first fixed end 411 of the first control switch 410 (i.e. the Pin3 pin of the first control switch 410) is electrically connected with the intake valve control signal output port of the industrial computer, and the second fixed end 412 of the first control switch 410 (i.e. the Pin6 pin of the first control switch 410) is electrically connected with the pressure relief valve control signal output port of the industrial computer;

[0064] The first fixed end 411 corresponds to the first normally open contact 413 (i.e. the Pin4 pin of the first control switch 410), which is electrically connected with the control end of the second control switch 420, and the second fixed end 412 corresponds to the second normally open contact 414 (i.e. the Pin5 pin of the first control switch 410), which is suspended;

[0065] The first fixed end 411 corresponds to the first normally closed contact 415 (i.e. the Pin2 pin of the first control switch 410), and the second fixed end 412 corresponds to the second normally closed contact 416 (i.e. the Pin7 pin of the first control switch 410), which are respectively connected to the signal input end (i.e. the Pin1 pin of the second control switch 420) of the second control switch 420.

[0066] The second control switch 420 is a double-pole double-throw relay. The third stationary terminal 421 of the second control switch 420 (i.e., the Pin3 pin of the second control switch 420) is electrically connected to the intake valve 220, and the fourth stationary terminal 422 of the second control switch 420 (i.e., the Pin6 pin of the second control switch 420) is electrically connected to the pressure relief valve.

[0067] The third normally open contact 423 (i.e., the Pin4 pin of the second control switch 420) corresponding to the third fixed terminal 421 is left floating, and the fourth normally open contact 424 (i.e., the Pin5 pin of the second control switch 420) corresponding to the fourth fixed terminal 422 is connected to a high level.

[0068] The third normally closed contact 425 (i.e., the Pin2 pin of the second control switch 420) corresponding to the third stationary terminal 421 and the fourth normally closed contact 426 (i.e., the Pin7 pin of the second control switch 420) corresponding to the fourth stationary terminal 422 serve as the signal input terminals of the second control switch 420, and are electrically connected to the first normally closed contact 415 and the second normally closed contact 416, respectively.

[0069] As an optional embodiment of the present invention, such as Figure 2 As shown, the first end of the electromagnetic winding of the first control switch 410 (i.e., the Pin1 pin of the first control switch 410) is connected to a high level through the third control switch S1, and the second end of the electromagnetic winding of the first control switch 410 (i.e., the Pin8 pin of the first control switch 410) is grounded. The third control switch S1 is turned on when the electrostatic adsorption voltage is less than a preset voltage threshold and turned off when the electrostatic adsorption voltage is greater than or equal to the preset voltage threshold. The first end of the electromagnetic winding of the second control switch 420 (i.e., the Pin1 pin of the second control switch 420) is connected to the first normally open contact 413 corresponding to the first stationary end 411, and the second end of the electromagnetic winding of the second control switch 420 (i.e., the Pin8 pin of the second control switch 420) is grounded.

[0070] As an optional embodiment of the present invention, the interlock circuit 400 further includes a voltage comparator (not shown in the figure), and the voltage sensor is used to control the third control switch S1 to open when the electrostatic adsorption voltage is greater than or equal to a preset voltage threshold, and to control the third control switch S1 to open when the electrostatic adsorption voltage is less than the preset voltage threshold.

[0071] As an optional embodiment of the present invention, the voltage sensor 300 of the semiconductor process equipment can send an electrical signal, such as an analog signal, to the interlock circuit 400 to characterize the magnitude of the electrostatic adsorption voltage. The interlock circuit 400 determines whether the electrostatic adsorption voltage is greater than a preset voltage threshold using its own voltage comparator. Specifically:

[0072] The voltage sensor 300 is configured to generate a voltage characterization signal based on the detected electrostatic adsorption voltage, and the voltage comparator is configured to compare the voltage characterization signal with a threshold level signal corresponding to a preset voltage threshold, and control the third control switch S1 to be turned off when the voltage characterization signal is greater than or equal to the threshold level signal, so as to make the electromagnetic winding of the first control switch 410 be powered off, and control the third control switch S1 to be turned on when the voltage characterization signal is less than the threshold level signal, so as to make the electromagnetic winding of the first control switch 410 be powered on.

[0073] As an optional embodiment of the present application, the interlocking circuit 400 further comprises a voltage division adjustment circuit configured to provide the threshold level signal to the voltage comparator.

[0074] As an optional embodiment of the present application, as shown in Figure 2 the interlocking circuit 400 further comprises an input terminal P1, an output terminal P2 and a reference voltage terminal P3, the input terminal P1 is configured to receive control signals of the intake valve and the pressure relief valve from the industrial computer respectively, the output terminal P2 is configured to output switching signals of the intake valve and the pressure relief valve respectively, and the reference voltage terminal P3 is configured to provide a high voltage Vcc and a ground voltage respectively.

[0075] The first fixed terminal 411 and the second fixed terminal 412 are connected with the input terminal P1 (specifically, the first fixed terminal 411 is connected with the first pin of the input terminal P1 through a wire 401, and the second fixed terminal 412 is connected with the second pin of the input terminal P1 through a wire 402), and the third fixed terminal 421 and the fourth fixed terminal 422 are connected with the output terminal P2 (specifically, the third fixed terminal 421 is connected with the first pin of the output terminal P2 through a wire 403, and the fourth fixed terminal 422 is connected with the second pin of the output terminal P2 through a wire 404).

[0076] The second end of the electromagnetic winding of the first control switch 410 and the second end of the electromagnetic winding of the second control switch 420 are grounded through the reference voltage terminal P3, and the first end of the electromagnetic winding of the first control switch 410 and the fourth normally open contact 424 are connected with the high voltage Vcc through the reference voltage terminal P3.

[0077] For the convenience of understanding, as shown in Figure 3 the functional logic diagram of the interlocking circuit provided by the embodiment of the present application, when the industrial computer does not send an intake valve opening signal (i.e. an intake valve DO signal) and does not send a pressure relief valve opening signal (i.e. a pressure relief valve DO signal), no signal is transmitted to the intake valve 220 and the pressure relief valve 230 through the first control switch 410 and the second control switch 420 of the interlocking circuit 400, and the intake valve 220 and the pressure relief valve 230 do not make any action.

[0078] When the industrial computer does not send the intake valve opening signal but sends the pressure relief valve opening signal, the interlocking circuit 400 first judges whether the electrostatic adsorption voltage is less than the preset voltage threshold value, if the electrostatic adsorption voltage is less than the preset voltage threshold value, the first control switch 410 is turned on, the intake valve opening signal and the pressure relief valve opening signal are both cut off, and the pressure relief valve 230 does not make any action; if the electrostatic adsorption voltage is greater than or equal to the preset voltage threshold value, the pressure relief valve opening signal is normally transmitted to the pressure relief valve 230 through the first control switch 410 and the second control switch 420, so that the pressure relief valve 230 is opened.

[0079] When the industrial computer sends the intake valve opening signal, the interlocking circuit 400 first judges whether the electrostatic adsorption voltage is less than the preset voltage threshold value, if the electrostatic adsorption voltage is greater than or equal to the preset voltage threshold value, the first control switch 410 and the second control switch 420 do not make any action, the intake valve opening signal is normally transmitted to the intake valve 220, so that the intake valve 220 is opened; if the electrostatic adsorption voltage is less than the preset voltage threshold value, the third control switch S1 is turned on, the first control switch 410 is powered on and closed, and then the second control switch 420 is closed, the control end of the pressure relief valve 230 is connected with the high voltage Vcc, the pressure relief valve 230 is opened, and the gas in the back blow pipeline is discharged, so as to ensure the safety of the cavity 110.

[0080] As a second aspect of the present application, a semiconductor process equipment is provided, such as Figure 1 As shown in the figure, it comprises a cavity 110, an electrostatic chuck 120, a back blow pipeline, a controller 500 (industrial computer) voltage sensor 300 and the interlocking circuit 400 provided by the embodiment of the present application, the electrostatic chuck 120 is arranged in the cavity 110 and is used for adsorbing the wafer 10 by electrostatic adsorption, the back blow pipeline 210 is provided with an intake valve 220 and a pressure relief valve 230, and the interlocking circuit 400 is used for outputting switch signals to the intake valve 220 and the pressure relief valve 230 according to the electrostatic adsorption voltage of the electrostatic chuck 120 detected by the voltage sensor 300.

[0081] In the semiconductor process equipment provided by the present application, when the electrostatic chucking force of the electrostatic chuck 120 is sufficient to fix the wafer 10 (i.e., when the electrostatic chucking voltage is greater than or equal to the preset voltage threshold), the interlocking circuit 400 can normally transmit the control signal of the industrial computer to the air inlet valve 220 and the pressure relief valve 230 to open or close the pressure relief valve. When the electrostatic chucking force of the electrostatic chuck 120 is too small (i.e., when the electrostatic chucking voltage is less than the preset voltage threshold), the air inlet valve 220 is controlled to be closed and the pressure relief valve 230 is controlled to be opened, so that the local hardware interlocking is realized through the voltage sensor 300 and the interlocking circuit 400 of the semiconductor process equipment. Even if the industrial computer misjudges and sends an incorrect control signal due to a failure of the power supply assembly 600, the back-blowing pipeline 210 will not supply air when the electrostatic chucking force of the electrostatic chuck 120 is too small, thereby avoiding damage to the wafer 10 caused by wafer drift or flying piece collision, and ensuring the safety of the semiconductor process and the product yield of the wafer 10.

[0082] In addition, in the present application, the interlocking circuit 400 is directly used to realize the interlocking cut-off control, and the original control signal of the industrial computer can be reused to achieve the necessary process of stopping air supply + pressure relief, thereby avoiding the development cost of redesigning the software process of the industrial computer. By directly adding a device, the corresponding function can be realized, and the adaptability of the semiconductor process equipment to different machines is improved.

[0083] As an optional embodiment of the present application, as shown in Figure 1 The semiconductor process equipment further includes an electromagnetic valve group 700, the electromagnetic valve group 700 includes an air inlet electromagnetic valve and a pressure relief electromagnetic valve, the air inlet valve 220 and the pressure relief valve 230 are both pneumatic valves, and the air inlet electromagnetic valve and the pressure relief electromagnetic valve are used to control the on-off of the air inlet valve 220 and the pressure relief valve 230, respectively. The control end of the air inlet electromagnetic valve is connected with the air inlet signal output end 403, and the control end of the pressure relief electromagnetic valve is connected with the pressure relief signal output end 404.

[0084] As an optional embodiment of the present application, as shown in Figure 1 The semiconductor process equipment further includes a power supply assembly 600, and the power supply assembly 600 is used to provide the electrostatic chucking voltage for the electrostatic chuck 120.

[0085] As an optional embodiment of the present application, the power supply assembly 600 includes a high-voltage direct-current power supply 610 and a direct-current filter box 620, the direct-current filter box 620 is connected between the high-voltage direct-current power supply 610 and the electrostatic chuck 120, and the high-voltage direct-current power supply 610 is used to provide the electrostatic chucking voltage for the electrostatic chuck 120 through the direct-current filter box 620.

[0086] As an optional embodiment of the present application, the temperature control gas is helium, and the semiconductor process equipment further includes a helium source, and the helium source is used to provide the temperature control gas for the back-blowing pipeline 210.

[0087] It is understood that the above embodiments are only exemplary for illustrating the principles of the present application, and the present application is not limited thereto. Various modifications and improvements can be made by those skilled in the art without departing from the spirit and scope of the present application, and these modifications and improvements are also considered to be within the scope of the present application.

Claims

1. An interlocking circuit for a back-blowing pipe of an electrostatic chuck, characterized in that, Includes a first control switch and a second control switch, wherein The first terminal of the first control switch is electrically connected to the intake valve control signal output port of the industrial computer, the second terminal of the first control switch is electrically connected to the pressure relief valve control signal output port of the industrial computer, and the third terminal of the first control switch is electrically connected to the control terminal of the second control switch. The first control switch is triggered when the electrostatic adsorption voltage of the electrostatic chuck is less than a preset voltage threshold, so that the first terminal and the third terminal are connected to disconnect the pressure relief valve control signal output by the industrial computer and connect the intake valve control signal output by the industrial computer to the control terminal of the second control switch. The fourth terminal of the second control switch is used to electrically connect to the air intake valve of the back-blowing pipeline, and the fifth terminal of the second control switch is electrically connected to the pressure relief valve of the back-blowing pipeline. When the control terminal of the second control switch is connected to the air intake valve control signal, if the air intake valve control signal is open, the second control switch is triggered so that the air intake valve is closed and the pressure relief valve is opened. or If the intake valve control signal is closed, the second control switch is not triggered, so that the intake valve and the pressure relief valve are closed.

2. The interlocking circuit according to claim 1, characterized in that, When the control terminal of the second control switch is connected to the intake valve control signal, if the intake valve control signal is open, the second control switch is triggered, outputting a high-resistance signal to the intake valve and a high-level signal to the pressure relief valve; or If the intake valve control signal is closed, the second control switch is not triggered, and high-resistance signals are output to the intake valve and the pressure relief valve respectively.

3. The interlocking circuit according to claim 1, characterized in that, The first control switch is also used to connect the intake valve control signal and the pressure relief valve control signal to the intake valve and the pressure relief valve respectively when the electrostatic adsorption voltage is greater than or equal to the preset voltage threshold.

4. The interlocking circuit according to claim 3, characterized in that, The intake valve control signal and the pressure relief valve control signal are respectively connected to the intake valve and the pressure relief valve via the second control switch.

5. The interlocking circuit according to claim 1, characterized in that, The first control switch is a double-pole double-throw relay. The first stationary terminal of the first control switch is electrically connected to the air intake valve control signal output port of the industrial computer, and the second stationary terminal of the first control switch is electrically connected to the pressure relief valve control signal output port of the industrial computer. The first normally open contact corresponding to the first stationary terminal is electrically connected to the control terminal of the second control switch, and the second normally open contact corresponding to the second stationary terminal is left floating. The first normally closed contact corresponding to the first stationary terminal and the second normally closed contact corresponding to the second stationary terminal are respectively connected to the signal input terminal of the second control switch.

6. The interlocking circuit according to claim 5, characterized in that, The second control switch is a double-pole double-throw relay. The third stationary terminal of the second control switch is electrically connected to the intake valve, and the fourth stationary terminal of the second control switch is electrically connected to the pressure relief valve. The third normally open contact corresponding to the third stationary terminal is left floating, and the fourth normally open contact corresponding to the fourth stationary terminal is connected to a high level. The third normally closed contact corresponding to the third stationary terminal and the fourth normally closed contact corresponding to the fourth stationary terminal serve as signal input terminals of the second control switch, and are electrically connected to the first normally closed contact and the second normally closed contact, respectively.

7. The interlocking circuit according to claim 6, characterized in that, The first end of the electromagnetic winding of the first control switch is connected to a high level through the third control switch, the second end of the electromagnetic winding of the first control switch is grounded, and the third control switch is turned on when the electrostatic adsorption voltage is less than the preset voltage threshold and turned off when the electrostatic adsorption voltage is greater than or equal to the preset voltage threshold. The first end of the electromagnetic winding of the second control switch is connected to the first normally open contact corresponding to the first stationary end, and the second end of the electromagnetic winding of the second control switch is grounded.

8. The interlocking circuit according to claim 7, characterized in that, The interlock circuit further includes a voltage comparator, which is used to control the third control switch to open when the electrostatic adsorption voltage is greater than or equal to the preset voltage threshold, and to control the third control switch to open when the electrostatic adsorption voltage is less than the preset voltage threshold.

9. The interlocking circuit according to claim 7, characterized in that, The interlock circuit further includes an input connector, an output connector, and a reference voltage connector. The input connector is used to receive control signals from the industrial computer to the intake valve and the pressure relief valve, respectively. The output connector is used to output switching signals to the intake valve and the pressure relief valve, respectively. The reference voltage connector is used to provide a high level and ground, respectively. Both the first stationary end and the second stationary end are connected to the input connector, and both the third stationary end and the fourth stationary end are connected to the output connector; The second end of the electromagnetic winding of the first control switch and the second end of the electromagnetic winding of the second control switch are both grounded through the reference voltage connector, and the first end of the electromagnetic winding of the first control switch and the fourth normally open contact are both connected to a high level through the reference voltage connector.

10. A semiconductor process apparatus, comprising a cavity, an electrostatic chuck, a back-blowing line, a controller, a voltage sensor, and an interlocking circuit as described in any one of claims 1 to 9, wherein the electrostatic chuck is disposed in the cavity and is used to adsorb wafers by electrostatic adsorption, the voltage sensor is used to detect the electrostatic adsorption voltage of the electrostatic chuck, the back-blowing line is provided with an inlet valve and a pressure relief valve, and the interlocking circuit is used to output switching signals to the inlet valve and the pressure relief valve according to the electrostatic adsorption voltage of the electrostatic chuck detected by the voltage sensor.

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