Adsorption Force Detection Device, Method, Storage Medium, and Semiconductor Processing Device

Abstract

The present invention provides a detecting device for wafer adsorption force, a detecting method for wafer adsorption force, and a processing device for semiconductor devices. The detecting device for wafer adsorption force includes: a laser emitter, disposed at a preset height on a first sidewall of a process chamber and facing a lifting path along which a wafer to be detected is lifted, wherein the preset height is determined according to a separation height at which the wafer to be detected is ejected to a separated state; a laser sensor, disposed at the preset height on a second sidewall of the process chamber and facing the laser emitter to obtain the laser emitted by the laser emitter and passing through the lifting path; and a processor, communicatively connected to the laser sensor and configured to: determine a waveform of the obtained laser over time; and analyze the waveform to determine the adsorption force applied to the wafer to be detected.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor processing technologies, and in particular, to a detection device for wafer adsorption force, a detection method for wafer adsorption force, and a processing device for semiconductor devices. Background Art

[0002] In the field of semiconductor processing, an Electro-Static Chuck (ESC) is one of the core components in a high-density plasma chemical vapor deposition device. The ESC achieves electrostatic adsorption of a wafer through internal charging, and eliminates the adsorption force through discharging to release the wafer. However, in actual use, it is a yet-to-be-solved problem to confirm whether the ESC discharging is complete. The existing technologies in this field currently cannot confirm the discharging effect of the ESC by detecting the wafer adsorption force, which further may cause the wafer to be lifted by a pin when the ESC is not completely discharged, resulting in the wafer position deviation being unable to be transmitted or the wafer being fragmented.

[0003] In order to overcome the above-mentioned defects existing in the prior art, there is an urgent need in this field for a detection device for wafer adsorption force to determine whether the suction force between the wafer and the ESC has been completely eliminated, so as to improve the economy and reliability of semiconductor processing equipment. Summary of the Invention

[0004] The following presents a brief overview of one or more aspects to provide a basic understanding of these aspects. This overview is not an exhaustive survey of all contemplated aspects, and is neither intended to identify key or critical elements of all aspects nor to delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to a more detailed description to follow.

[0005] In order to overcome the above-mentioned defects existing in the prior art, the present invention provides a detection device for wafer adsorption force, a detection method for wafer adsorption force, and a processing device for semiconductor devices, which can determine whether the suction force between the wafer and the ESC has been completely eliminated, so as to improve the economy and reliability of semiconductor processing equipment.

[0006] Specifically, the above-mentioned detection device for the adsorption force of a wafer provided according to the first aspect of the present invention includes: a laser emitter, which is provided at a preset height on the first sidewall of the process chamber and faces the lifting path where the wafer to be measured is lifted. The preset height is determined according to the separation height at which the wafer to be measured is ejected to the separated state; a laser sensor, which is provided at the preset height on the second sidewall of the process chamber and faces the laser emitter to obtain the laser emitted by the laser emitter and passing through the lifting path; and a processor, which is communicatively connected to the laser sensor and is configured to: determine the waveform of the obtained laser over time; and analyze the waveform to determine the adsorption force received by the wafer to be measured.

[0007] Further, in some embodiments of the present invention, the laser injected into the lifting path at the preset height by the detection device is blocked by the wafer to be measured in the ejected-to-separated state, and is not blocked by the wafer to be measured in the adsorbed state and / or the ejected-to-lifted state.

[0008] Further, in some embodiments of the present invention, the step of determining the waveform of the obtained laser over time includes: in response to the operation of the ejector pin for lifting the wafer to be measured, starting to record the intensity of the obtained laser; and determining the waveform of the laser over time according to the recorded intensity of the laser.

[0009] Further, in some embodiments of the present invention, the step of analyzing the waveform to determine the adsorption force received by the wafer to be measured includes: determining that the adsorption force received by the wafer to be measured is greater than the lifting force provided by the ejector pin according to the laser waveform that decreases and does not rise again; and / or determining that the adsorption force received by the wafer to be measured is zero according to the laser waveform that decreases and rises steadily; and / or determining that the adsorption force received by the wafer to be measured is not zero and less than the lifting force provided by the ejector pin according to the laser waveform that decreases and rises with jitter.

[0010] Further, in some embodiments of the present invention, the step of analyzing the waveform to determine the adsorption force received by the wafer to be measured includes: lifting the wafer to be measured to the lifted state under normal operating conditions where the adsorption force is zero to pre-calibrate the standard waveform of the laser; comparing the measured waveform of the obtained laser with the standard waveform; and determining that the adsorption force received by the wafer to be measured is not zero in response to the comparison result that the measured waveform is inconsistent with the standard waveform.

[0011] Further, in some embodiments of the present invention, the laser emitter is disposed on the first sidewall via a first mounting groove, and the laser sensor is disposed on the second sidewall via a second mounting groove. Wherein, a light-transmitting sealing sheet is provided at the opening of the first mounting groove and / or the second mounting groove in the process chamber. The laser emitter and the laser sensor transmit the laser via the light-transmitting sealing sheet. A metal mesh is provided on the first surface of the light-transmitting sealing sheet facing the process chamber to conduct the radio frequency on the inner surface of the process chamber. A polarizing sheet is provided on the second surface of the light-transmitting sealing sheet facing the first mounting groove and / or the second mounting groove to filter the glow in the process chamber. Wherein, the polarization direction of the polarizing sheet conforms to the transmission direction of the laser.

[0012] In addition, a method for detecting the wafer adsorption force provided by the second aspect of the present invention includes the following steps: shooting a laser into the lifting path where the wafer to be measured is lifted at a preset height, wherein the preset height is determined according to the separation height at which the wafer to be measured is ejected to the separated state; receiving the laser passing through the lifting path at the preset height; determining the waveform of the received laser over time; and analyzing the waveform to determine the adsorption force received by the wafer to be measured.

[0013] In addition, a processing device for a semiconductor device provided by the third aspect of the present invention includes an electrostatic chuck for carrying and adsorbing a wafer; at least one ejector pin disposed on the electrostatic chuck for lifting the wafer; a wafer adsorption force detection device according to any one of claims 1 to 6; and a controller communicatively connected to the at least one ejector pin and configured to: determine the adsorption force received by the wafer via the detection device; and control the at least one ejector pin to lift the wafer according to the adsorption force.

[0014] Further, in some embodiments of the present invention, the step of controlling the at least one ejector pin to lift the wafer according to the adsorption force includes: in response to the detection result that the adsorption force is zero, driving the at least one ejector pin to lift the wafer to the lifted state; and in response to the detection result that the adsorption force is not zero, stopping the operation of driving the at least one ejector pin and / or giving an alarm. Description of the Drawings

[0015] After reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings, the above features and advantages of the present invention can be better understood. In the drawings, the components are not necessarily drawn to scale, and components having similar related characteristics or features may have the same or similar reference numerals.

[0016] Figure 1 A schematic diagram of a processing apparatus for a semiconductor device according to some embodiments of the present invention is shown.

[0017] Figure 2 The schematic diagram of a laser emitter provided according to some embodiments of the present invention is shown.

[0018] Figure 3 The schematic diagram of a laser sensor provided according to some embodiments of the present invention is shown.

[0019] Figures 4A to 4D The schematic diagram of the detection process of a wafer adsorption force detection device provided according to some embodiments of the present invention is shown.

[0020] Figures 5A to 5C The schematic diagram of the detection optical signal intensity of a wafer adsorption force detection device provided according to some embodiments of the present invention is shown.

[0021] Figure 6 The schematic diagram of the flow of a method for detecting a wafer adsorption force provided according to some embodiments of the present invention is shown. Detailed implementation manners

[0022] The following specific embodiments illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Although the description of the present invention will be introduced in conjunction with preferred embodiments, this does not mean that the features of this invention are limited to this implementation manner. On the contrary, the purpose of introducing the invention in conjunction with the implementation manner is to cover other alternatives or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, many specific details will be included in the following description. The present invention can also be implemented without using these details. In addition, in order to avoid confusing or obscuring the key points of the present invention, some specific details will be omitted in the description.

[0023] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0024] In addition, the "upper", "lower", "left", "right", "top", "bottom", "horizontal", and "vertical" used in the following description should be understood as the orientations shown in this section and the related drawings. This relative term is only for the convenience of description, and it does not mean that the device described needs to be manufactured or operated in a specific orientation, so it should not be understood as a limitation to the present invention.

[0025] It will be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various components, regions, layers, and / or portions, these components, regions, layers, and / or portions should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers, and / or portions. Thus, the first component, region, layer, and / or portion discussed below may be referred to as the second component, region, layer, and / or portion without departing from some embodiments of the present invention.

[0026] As described above, in the field of semiconductor processing, an Electro-Static Chuck (ESC) is one of the core components in a high-density plasma chemical vapor deposition device. The ESC achieves electrostatic adsorption of a wafer through internal charging and eliminates the adsorption force through discharging to release the wafer. However, in actual use, it is still an unsolved problem to confirm whether the ESC has completely discharged. The existing technologies in this field currently cannot confirm the discharging effect of the ESC by detecting the adsorption force of the wafer, which may further cause the wafer to be lifted by a pin when the ESC has not completely discharged, resulting in the wafer position deviation being unable to be transmitted or the wafer being fragmented.

[0027] To overcome the above-mentioned defects existing in the prior art, the present invention provides a detecting device for wafer adsorption force, a detecting method for wafer adsorption force, and a processing device for semiconductor devices, which can determine whether the suction force between the wafer and the ESC has been completely eliminated, so as to improve the economy and reliability of semiconductor processing equipment.

[0028] In some non-limiting embodiments, the above-mentioned detecting method for wafer adsorption force provided by the second aspect of the present invention can be implemented by the above-mentioned detecting device for wafer adsorption force provided by the first aspect of the present invention. The detecting device can be configured in the above-mentioned processing device for semiconductor devices provided by the fourth aspect of the present invention, which is equipped with a memory and a processor. The memory includes but is not limited to the above-mentioned computer-readable storage medium provided by the third aspect of the present invention, on which computer instructions are stored. The processor is connected to the memory and is configured to execute the computer instructions stored on the memory to implement the above-mentioned detecting method for wafer adsorption force provided by the second aspect of the present invention.

[0029] First, please refer to Figure 1 , Figure 1 which shows a schematic diagram of a processing device for semiconductor devices provided by some embodiments of the present invention.

[0030] As Figure 1As shown, in some embodiments of the present invention, the processing apparatus for a semiconductor device provided by the second aspect of the present invention includes an electrostatic chuck 11, an ejector pin 12, a detecting device for the wafer adsorption force, and a controller (not shown). The electrostatic chuck 11 is used to carry and adsorb the wafer. The first end of the ejector pin 12 abuts against the lower side of the electrostatic chuck 11, and its second end abuts against the base of the semiconductor device, and is used to lift the above-mentioned wafer. The detecting device for the wafer adsorption force includes a laser emitter 13, a light sensor 14, and a processor (not shown). The laser emitter 13 is disposed at a preset height on the first sidewall 15 of the process chamber of the semiconductor device. The preset height can be determined according to the separation height at which the above-mentioned wafer to be measured is ejected to the separation state. The preset height can be higher than the wafer receiving surface and lower than the height of the ejector pin separation position. Preferably, the preset height can be 1 mm higher than the wafer receiving surface 1 mm. The controller is communicatively connected to the ejector pin 12, and the controller is configured to determine the adsorption force received by the above-mentioned wafer via the detecting device, and control the ejector pin 12 to lift the above-mentioned wafer according to the adsorption force.

[0031] In addition, please refer to Figure 2 in conjunction with Figure 3 . Figure 2 The schematic diagram of the laser emitter provided by some embodiments of the present invention is shown. Figure 3 The schematic diagram of the laser sensor provided by some embodiments of the present invention is shown.

[0032] As Figure 2 and Figure 3 shown, the above-mentioned laser emitter 22 can be disposed on the first sidewall 15 via the first mounting groove 21. The above-mentioned laser sensor 32 is disposed on the second sidewall via the second mounting groove 31. The first mounting groove 21 and the second mounting groove 31 are provided with light-transmitting sealing sheets 24, 34 at the openings of the process chamber. The laser emitter 22 and the laser sensor 32 transmit the laser through the light-transmitting sealing sheet 24. The first surface of the light-transmitting sealing sheet 24 facing the process chamber is provided with a metal mesh to conduct the radio frequency of the inner surface of the process chamber. The second surface of the light-transmitting sealing sheet 24 facing the first mounting groove and the second mounting groove is provided with polarizing sheets 23, 33 for screening light sources and defining the direction of acceptable light. In this way, the light source can be screened and the direction of acceptable light can be defined. The polarization directions of the polarizing sheets 23, 33 are consistent with the transmission direction of the laser.

[0033] Preferably, the openings of the first mounting groove and the second mounting groove can be sealed. Here, a high light transmittance material can be used to seal the groove openings to avoid a gap of more than 1 mm in the chamber when the radio frequency is turned on, thereby avoiding the occurrence of tip discharge phenomenon. The high light transmittance material can include, but is not limited to, sapphire material.

[0034] Preferably, the laser sensor 32 can be further set with a threshold value for screening light sources and specifying the direction of acceptable light rays.

[0035] In some other embodiments of the present invention, the wavelength range of glow can be avoided by selecting the transmission / reception wavelengths of the above-mentioned laser emitter 22 and the above-mentioned laser sensor 32.

[0036] The working principle of the above-mentioned wafer adsorption force detection device will be described below in conjunction with some embodiments of the wafer adsorption force detection method. Those skilled in the art can understand that these embodiments of the wafer adsorption force detection method are only some non-restrictive implementation manners provided by the present invention, aiming to clearly show the main concept of the present invention and provide some specific solutions convenient for the public to implement, rather than limiting all functions or all working modes of the wafer adsorption force detection device. Similarly, the wafer adsorption force detection device is also a non-restrictive implementation manner provided by the present invention and does not limit the execution subject of each step in these wafer adsorption force detection methods.

[0037] Please refer to Figure 1 、 Figures 4A to 4D 、 Figures 5A to 5C and Figure 6 . Figures 4A to 4D Fig. shows a schematic diagram of the detection process of the wafer adsorption force detection device provided according to some embodiments of the present invention. Figures 5A to 5C Fig. shows a schematic diagram of the detection optical signal intensity of the wafer adsorption force detection device provided according to some embodiments of the present invention. Figure 6 Fig. shows a schematic flow chart of a wafer adsorption force detection method provided according to some embodiments of the present invention.

[0038] Furthermore, as Figure 4A shown, during the process of the above-mentioned ejector pin 12 lifting the above-mentioned electrostatic chuck 11, initially, the above-mentioned wafer to be measured 43 is not ejected to the lifted state or the above-mentioned wafer to be measured 43 is adsorbed by the electrostatic chuck 11. Therefore, the wafer will not block the laser emitted by the above-mentioned laser emitter 41. Therefore, the above-mentioned detection device will not be blocked by the wafer to be measured 43 in the adsorbed state and / or ejected to the lifted state. As Figure 4B 、 Figure 4C shown, as the ejector pin 12 further lifts the electrostatic chuck 11, when the wafer is ejected to the separated state, the wafer to be measured 43 will block part of the laser emitted by the above-mentioned laser emitter 41, resulting in the laser sensor 42 being unable to fully receive all the laser emitted by the laser emitter 41.

[0039] Further, the processor of the detection device can be configured to record the acquired laser intensity in response to the operation of the ejector pin 12, and determine the waveform of the laser over time based on the recorded laser intensity. The processor can also analyze the waveform to determine the adsorption force exerted on the wafer 43 to be measured.

[0040] Specifically, the present invention can measure the wafer 43 to be measured through the detection device to obtain the actual waveform of the wafer 43 to be measured. As Figure 5A shown, when the waveform is a waveform that decreases and then steadily rises, it can be determined that the wafer 43 to be measured blocks the laser emitter 41 during the process of being lifted, thus blocking the optical path once, and then releasing the optical path. In this way, it can be explained that the surface of the wafer 43 to be measured is flat and the wafer is normally released without any chip jumping. Therefore, it can be determined that the adsorption force exerted on the wafer 43 to be measured is zero. As Figure 5B shown, when the waveform is a waveform that decreases and does not rise again, it can be determined that the central part of the surface of the wafer 43 to be measured bulges and continuously blocks the optical path, and the edge of the wafer 43 to be measured does not bulge and block the optical path. Thus, it can be determined that the center of the wafer 43 to be measured is lifted by the ejector pin 12, but the edge is still adsorbed by the electrostatic chuck 11. Since the bulging part continuously blocks the optical path, the received signal will not rise. In this way, it can be determined that the adsorption force exerted on the wafer 43 to be measured is greater than the lifting force provided by the ejector pin 12. As Figure 5C shown, when the waveform is a waveform that decreases and jitters and then rises, it can be determined that the blocking situation of the wafer is irregular, and thus it can be determined that the wafer 43 to be measured is not normally released and there is a chip jumping reception situation. In this way, it can be determined that the adsorption force exerted on the wafer 43 to be measured is not zero and is less than the lifting force provided by the ejector pin 12.

[0041] In this way, the present invention can determine whether the suction force between the wafer and the electrostatic chuck has been completely eliminated, so as to improve the economy and reliability of semiconductor processing equipment.

[0042] Further, the present invention can also, before calibrating the actual waveform of the wafer 43 to be measured, pre-lift the wafer 43 to be measured to the lifted state under normal working conditions where the adsorption force is zero, so as to calibrate the standard waveform of the laser. Then, the actual waveform of the laser of the wafer 43 to be measured is calibrated by lifting the ejector pin. The present invention can compare the standard waveform with the actual waveform. When the standard waveform is the same as the actual waveform, it can be determined that the adsorption force of the wafer 43 to be measured is 0. When the standard waveform is different from the actual waveform, the above-mentioned judgment method can be used to determine the adsorption force exerted on the wafer. Details are not described here again.

[0043] Please further refer to Figures 1 to 6, during the process of detecting the wafer adsorption force, the detection device can first emit a laser into the lifting path where the above-mentioned wafer to be measured 43 is lifted at a preset height. The above-mentioned preset height is determined according to the separation height at which the above-mentioned wafer to be measured 43 is ejected to the separated state. After that, the detection device can receive the laser passing through the above-mentioned lifting path at this preset height and calibrate the waveform diagram of the received laser over time. After that, the detection device can analyze this waveform to determine the adsorption force received by the above-mentioned wafer to be measured 43. Since this method has been described in detail in the specific implementation of the above-mentioned detection device for wafer adsorption force, it will not be elaborated here.

[0044] In summary, since there is no detection device in the prior art of this field that can confirm the electrostatic chuck discharge effect by detecting the wafer adsorption force, the detection device for wafer adsorption force provided by the present invention can determine whether the suction force between the wafer and the electrostatic chuck has been completely eliminated, so as to improve the economy and reliability of semiconductor processing equipment.

[0045] Although the above method is illustrated and described as a series of actions for simplicity of explanation, it should be understood and appreciated that these methods are not limited by the order of the actions, because according to one or more embodiments, some actions may occur in a different order and / or occur concurrently with other actions that are illustrated and described in this document or not illustrated and described in this document but can be understood by those skilled in the art.

[0046] The previous description of the present disclosure is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to the present disclosure will be apparent to those skilled in the art, and the general principles defined herein can be applied to other variations without departing from the spirit or scope of the present disclosure. Thus, the present disclosure is not intended to be limited to the examples and designs described herein, but should be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A detecting device for the adsorption force of a wafer, characterized in that, Comprising: A laser emitter, disposed at a preset height on the first sidewall of the process chamber, and facing the lifting path along which a wafer under test adsorbed by an electrostatic chuck is lifted by at least one ejector pin, wherein the ejector pin is disposed on the electrostatic chuck and is used to lift the wafer, and the preset height is higher than the receiving surface of the wafer and lower than the separation height at which the wafer under test is ejected to the separated state; A laser sensor, disposed at the preset height on the second sidewall of the process chamber, and facing the laser emitter to obtain the laser emitted by the laser emitter and passing through the lifting path; and A processor, communicatively connected to the laser sensor and configured to: Determine the waveform of the obtained laser over time; and Analyze the waveform to determine the adsorption force applied to the wafer under test, wherein, Based on a laser waveform that drops and does not rise again, determine that the adsorption force applied to the wafer under test is greater than the lifting force provided by the ejector pin; and / or Based on a laser waveform that drops and steadily rises, determine that the adsorption force applied to the wafer under test is zero; and / or Based on a laser waveform that drops and jitterily rises, determine that the adsorption force applied to the wafer under test is non-zero and less than the lifting force provided by the ejector pin.

2. The detecting device according to claim 1, characterized in that, The laser injected into the lifting path at the preset height is blocked by the wafer under test ejected to the separated state, and is not blocked by the wafer under test in the adsorbed state and / or ejected to the lifted state.

3. The detecting device according to claim 2, characterized in that, The step of determining the waveform of the obtained laser over time includes: In response to the operation of the ejector pin for lifting the wafer under test, start recording the intensity of the obtained laser; and Based on the recorded intensity of the laser, determine the waveform of the laser over time.

4. The detecting device according to claim 1, characterized in that, The step of analyzing the waveform to determine the adsorption force applied to the wafer under test includes: Lift the wafer under test to the lifted state under normal operating conditions where the adsorption force is zero to pre-calibrate the standard waveform of the laser; Compare the measured waveform of the obtained laser with the standard waveform; and In response to a comparison result indicating that the measured waveform is inconsistent with the standard waveform, determine that the adsorption force applied to the wafer under test is non-zero.

5. The detecting device according to claim 1, characterized in that, The laser emitter is disposed on the first sidewall via a first mounting groove, and the laser sensor is disposed on the second sidewall via a second mounting groove, wherein, A light-transmitting sealing sheet is provided at the opening of the first mounting groove and / or the second mounting groove in the process chamber, and the laser emitter and the laser sensor transmit the laser via the light-transmitting sealing sheet, A metal mesh is provided on the first surface of the light-transmitting sealing sheet facing the process chamber to conduct the radio frequency on the inner surface of the process chamber, A polarizing sheet is provided on the second surface of the light-transmitting sealing sheet facing the first mounting groove and / or the second mounting groove to filter the glow in the process chamber, wherein the polarization direction of the polarizing sheet conforms to the transmission direction of the laser.

6. A detecting method for the adsorption force of a wafer, characterized in that, Including the following steps: Inject laser light into the lifting path along which a wafer under test is lifted by at least one ejector pin at a preset height, wherein the ejector pin is disposed on an electrostatic chuck and is used to lift the wafer, and the preset height is higher than the receiving surface of the wafer and lower than the separation height at which the wafer under test is ejected to the separated state; Receive the laser passing through the lifting path at the preset height to; Determine the waveform of the acquired laser over time; and Analyze the waveform to determine the adsorption force on the wafer to be measured, where According to the laser waveform that drops and does not rise again, determine that the adsorption force on the wafer to be measured is greater than the lifting force provided by the ejector pin; and / or According to the laser waveform that drops and rises steadily, determine that the adsorption force on the wafer to be measured is zero; and / or According to the laser waveform that drops and rises with jitter, determine that the adsorption force on the wafer to be measured is not zero and less than the lifting force provided by the ejector pin.

7. A computer-readable storage medium, on which computer instructions are stored, characterized in that, When the computer instructions are executed by a processor, implement the method for detecting the adsorption force of a wafer as described in claim 6.

8. A processing device for a semiconductor device, characterized in that, Comprising: An electrostatic chuck for carrying and adsorbing the wafer; The device for detecting the adsorption force of a wafer according to any one of claims 1 to 5; And A controller communicatively connected to the at least one ejector pin and configured to: determine the adsorption force on the wafer via the detection device; and control the at least one ejector pin to lift the wafer according to the adsorption force.

9. The processing device according to claim 8, wherein, The step of controlling the at least one ejector pin to lift the wafer according to the adsorption force includes: In response to the detection result that the adsorption force is zero, drive the at least one ejector pin to lift the wafer to the lifting state; and In response to the detection result that the adsorption force is not zero, stop the operation of driving the at least one ejector pin and / or give an alarm.

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