Wafer desorption apparatus, method, and semiconductor device

Abstract

The application discloses a wafer desorption device, method and semiconductor equipment, and belongs to the technical field of semiconductor equipment. The wafer desorption device comprises an electrostatic chuck, a conductive lifting pin, a conductive support seat, a lifting driving mechanism, a relay, a grounding end and a control module. The electrostatic chuck bears and fixes a wafer. The top of the conductive lifting pin penetrates through a through hole on the electrostatic chuck, contacts and lifts the wafer. The bottom end of the conductive lifting pin is connected with the conductive support seat and is conductive to the electrostatic chuck. One end of the relay is electrically connected with the conductive support seat, and the other end is connected with the grounding end. The control module controls the lifting driving mechanism to drive the conductive lifting pin to move up and down. The control module controls the on-off of the direct current loaded by the electrostatic chuck and controls the on-off of the relay. The application controls the timing of the discharge path through the control module and constructs a rapid discharge path, realizes the rapid and complete release of residual static electricity, and avoids the interference of the wafer lifting warping and the discharge path on the electric field of the electrostatic chuck.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a wafer de-adsorption apparatus, method and semiconductor equipment. Background Technology

[0002] In vacuum processes such as etching, deposition, and ion implantation of semiconductor wafers, the electrostatic chuck is a core wafer holding component. By applying a high-voltage electric field, it generates electrostatic force between the chuck's dielectric layer and the wafer, achieving contactless wafer holding and effectively avoiding the damage and contamination caused by traditional mechanical clamping. After the process is complete, the high-voltage power supply to the electrostatic chuck is first cut off, then the lifting pin rises, lifting the wafer off the surface of the electrostatic chuck, where it is then removed by a robotic arm.

[0003] After the electrostatic chuck is de-energized, a large amount of static charge remains on the surface of the wafer and the dielectric layer of the chuck, generating residual attraction. If the lifting pin is raised directly at this time, the wafer will be subjected to uneven stress, which can easily cause warping, microcracks, breakage, or surface scratches, especially for ultra-thin wafers. The residual static charge may undergo rapid charge transfer, i.e., electrostatic discharge, the instant the wafer is removed from the electrostatic chuck or comes into contact with the robotic arm. This instantaneous high-voltage pulse can break down or damage the delicate semiconductor devices and circuits on the wafer, significantly reducing chip production yield. Traditional passive discharge or simple grounding methods are not efficient enough to eliminate residual static electricity on large-size wafers within a reasonable time, making it difficult to meet the process cycle time and stability requirements of advanced manufacturing processes.

[0004] In the prior art, patent CN114743901A discloses a semiconductor process chamber, including a cavity, an electrostatic chuck, and a power supply component. The power supply component applies a desorption voltage to the adsorption electrodes of the electrostatic chuck, with the polarity alternating between positive and negative over a preset time period, the amplitude gradually decreasing until it reaches zero, to eliminate residual charge on the wafer. CN117373987A discloses a wafer desorption method, an electrostatic chuck, and semiconductor processing equipment. By turning off the electrostatic adsorption power supply and setting a desorption voltage, ensuring it is opposite in polarity to the previous adsorption voltage and less than the adsorption voltage, and then turning off the power after a preset time period, residual charge is released using conductive pins until the wafer reaches the pick-up position. CN108735624 discloses a wafer removal method. Before removing the wafer, the voltage applied to the electrostatic chuck stage is stopped, and a voltage in the opposite direction is applied to counteract the stripping charge. Air is ejected at the air outlet to eliminate vacuum adsorption force, ensuring the electrostatic chuck stage is uncharged when detached. The above method cancels out residual static electricity by applying voltage in the opposite direction. However, this requires the addition of a polarity switching circuit and a precise voltage control unit to the existing grounding path, which increases the overall structural complexity.

[0005] Therefore, there is an urgent need for a safe, fast, and controllable wafer desorption device and method. Summary of the Invention

[0006] This invention uses the conductive lifting pin, which is in direct contact with the wafer, as a point-to-point electrostatic discharge electrode. The timing of the discharge path is controlled by the control module only after the electrostatic chuck is de-energized, which realizes the rapid and complete release of residual static electricity on the wafer and avoids the interference of the discharge path on the electrostatic chuck electric field during wafer lifting due to warping and cleaving and the process stage discharge path.

[0007] On one hand, the present invention provides a wafer de-adsorption device, comprising: an electrostatic chuck, a conductive lifting pin, a conductive support base, a lifting drive mechanism, a relay, a grounding terminal, and a control module; wherein, the electrostatic chuck carries and fixes the wafer; the top of the conductive lifting pin passes through a through hole in the electrostatic chuck, contacts and lifts the wafer; the bottom end of the conductive lifting pin is fixedly connected to the conductive support base and conducts electricity to the electrostatic chuck; one end of the relay is electrically connected to the conductive support base, and the other end is connected to the grounding terminal; the control module controls the lifting drive mechanism to drive the conductive lifting pin to move up and down, the control module controls the on / off state of the DC current applied to the electrostatic chuck; the control module controls the on / off state of the relay, thereby controlling the grounding state of the conductive lifting pin.

[0008] Preferably, a current-limiting resistor is connected in series between the conductive support and the relay.

[0009] Preferably, the current-limiting resistor is a resistor with a fixed resistance or a resistor with an adjustable resistance.

[0010] Preferably, the control module further includes an electrostatic detection unit for monitoring the current value of the relay.

[0011] Preferably, the conductive lifting pin is made of conductive material and has a smooth, rounded top.

[0012] On the other hand, the present invention provides a wafer de-adsorption method, based on the aforementioned wafer de-adsorption device, comprising the following steps: During the wafer adsorption and processing stages, the relay remains in the off state; After the process stage is completed, the control module cuts off the DC power applied to the electrostatic chuck; After a delay of S1, the control module controls the relay to close, and the control module controls the lifting drive mechanism to drive the conductive lifting pin to move upward to the position of contacting the back of the wafer; the residual static electricity of the wafer and the electrostatic chuck is discharged through the conductive lifting pin, the conductive support base, the relay and the grounding terminal; After the residual static discharge time S2, the control module controls the conductive lifting pin to rise to the wafer retrieval position. After wafer retrieval is completed, the control module controls the relay to disconnect.

[0013] Preferably, during the residual static electricity discharge, the control module controls the static electricity detection unit to monitor the current value of the relay and determine whether the current value has dropped to within the preset discharge safety threshold. If so, the control module controls the lifting drive mechanism to drive the conductive lifting pin to move upward; otherwise, the discharge continues.

[0014] Preferably, during the residual static discharge, the control module controls the static detection unit to monitor the current value of the relay and determine whether the current value exceeds the discharge safety threshold. If so, the control module controls the current limiting resistor to increase its resistance value to reduce the peak current.

[0015] Preferably, the delay time S1 is 50-200ms and the residual static electricity discharge time S2 is 400-900ms.

[0016] In another aspect, the present invention provides a semiconductor device, including the aforementioned wafer de-adsorption device.

[0017] Compared with the prior art, the present invention has the following beneficial effects: (1) This invention relies on the direct physical contact between the conductive lifting pin and the back of the wafer and the electrostatic chuck, breaking the path limitation of the traditional electrostatic chuck which relies only on the weak indirect discharge path on the surface of the electrostatic chuck. It provides a low-impedance direct path to ground for the residual adsorbed charge, realizing the millisecond-level rapid and complete discharge of residual static electricity, completely eliminating the residual adsorption force of the electrostatic chuck on the wafer, and fundamentally avoiding wafer warping and cracking defects caused by uneven lifting force on the wafer, thus greatly reducing the wafer breakage rate.

[0018] (2) This invention uses a control module for logical timing control, strictly limiting the conduction window of the discharge path to the wafer desorption stage after the electrostatic chuck is de-energized. During the wafer adsorption and process stages, the discharge path remains completely disconnected, thoroughly severing the coupling between the discharge path and the internal electric field of the electrostatic chuck. The complete isolation of the discharge path during the wafer adsorption and process stages will not cause any disturbance to the electrostatic adsorption electric field or plasma process electric field inside the electrostatic chuck, thus improving process stability.

[0019] (3) By using the impedance voltage division characteristic of the current limiting resistor, the present invention extends the discharge time of residual charge on the wafer surface, stretches the original nanosecond-level instantaneous spontaneous discharge process to the millisecond level, controls the peak value of the discharge current within the safety threshold of the sensitive device, suppresses the generation of high voltage electrostatic discharge pulse from the source, avoids the nanoscale sensitive device on the wafer from being electrostatically broken down, and improves the chip production yield.

[0020] (4) The wafer de-adsorption device in this invention does not require modification of the mature design of the power supply and dielectric layer layout inside the electrostatic chuck. Only the lifting pin and control unit are upgraded, which is easy to modify and implement and has strong compatibility. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a wafer desorption device in one embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of a wafer desorption device in another embodiment of the present invention;

[0024] Figure 3 This is based on one embodiment of the present invention. Figure 1 A flowchart of the wafer desorption method for the device;

[0025] Figure 4 In another embodiment of the present invention, based on Figure 1 A flowchart of the wafer desorption method for the device;

[0026] Figure 5 This is based on one embodiment of the present invention. Figure 2 A flowchart of the wafer desorption method for the device;

[0027] Figure 6 In another embodiment of the present invention, based on Figure 2 A flowchart of the wafer desorption method for the device. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0029] like Figure 1As shown in one embodiment of the present invention, a wafer de-adsorption device includes: an electrostatic chuck 2, a conductive lifting pin 3, a conductive support base (not shown in the figure), a lifting drive mechanism 4, a relay 5, a grounding terminal 6, and a control module 7; wherein, the electrostatic chuck 2 carries and fixes the wafer 1; the top of the conductive lifting pin 3 passes through a through hole on the electrostatic chuck 2, contacts and lifts the wafer 1; the bottom end of the conductive lifting pin 3 is fixedly connected to the conductive support base, and the conductive support base is connected to the electrostatic chuck 2 and the lifting drive mechanism 4, so that the conductive lifting pin 3 conducts electricity to the electrostatic chuck 2; one end of the relay 5 is electrically connected to the conductive support base, and the other end is connected to the grounding terminal 6; the control module 7 controls the lifting drive mechanism 4 to drive the conductive lifting pin 3 to move up and down, the control module 7 controls the on / off state of the DC current applied to the electrostatic chuck 2; the control module 7 controls the on / off state of the relay 5, thereby controlling the grounding state of the conductive lifting pin 3.

[0030] The electrostatic chuck 2 of this invention adopts a bipolar structure, with an alumina ceramic dielectric layer, a bipolar adsorption electrode layer, and an aluminum alloy metal base arranged sequentially from top to bottom. Conductive lifting pins 3 are evenly distributed and penetrate corresponding through holes on the electrostatic chuck 2. The conductive lifting pins 3 are made of conductive material, and their bottom ends are fixed to a conductive support base made of metal. The conductive support base is connected to the electrostatic chuck 2. The relay 5 in this invention is a high-voltage DC relay. The input terminal of the relay 5 is electrically connected to the conductive support base, and then to the conductive lifting pins 3. The output terminal of the relay 5 is connected to the grounding terminal 6 of the process chamber.

[0031] In this invention, the control module 7 is a programmable logic controller. The input port of the control module 7 receives the on / off status signal of the DC power from the electrostatic chuck 2. The output port of the control module 7 controls the off state of the relay 5, controls the lifting drive mechanism 4 to drive the conductive lifting pin 3 to move up and down, and controls the on / off state of the DC power loaded on the electrostatic chuck 2.

[0032] This invention relies on the direct physical contact between the conductive lifting pin and the back of the wafer, and the connection with the electrostatic chuck. This breaks the limitation of traditional electrostatic chucks that rely solely on the weak indirect discharge path on the chuck surface. It provides a low-impedance direct path to ground for residual adsorbed charges, enabling the rapid and complete discharge of residual static electricity in milliseconds. This completely eliminates the residual adsorption force of the electrostatic chuck on the wafer, fundamentally avoiding wafer warping and cracking defects caused by uneven lifting forces on the wafer, and significantly reducing the wafer breakage rate.

[0033] Furthermore, this invention uses a control module to perform logical timing control on the relays, strictly limiting the conduction window of the discharge path to the wafer desorption stage after the electrostatic chuck is de-energized. The wafer adsorption and process stage control modules maintain the discharge path completely disconnected by controlling the relays, thoroughly severing the coupling between the discharge path and the internal electric field of the electrostatic chuck. The complete isolation of the discharge path during wafer adsorption and process stages prevents any disturbance to the electrostatic adsorption electric field or plasma process electric field inside the electrostatic chuck, thus improving process stability.

[0034] like Figure 2 As shown, in another embodiment of the present invention, a current-limiting resistor 8 is connected in series between the conductive support base and the relay 5.

[0035] In another embodiment, the current-limiting resistor 8 is a resistor with a fixed resistance or a resistor with an adjustable resistance.

[0036] The current-limiting resistor 8 is connected in series between the conductive support and the relay 5, that is, the current-limiting resistor 8 is connected in series in the discharge path. Through the impedance voltage division characteristic of the current-limiting resistor 8, the total impedance of the discharge path is greatly increased, the RC discharge time constant is lengthened, the discharge time of residual charge on the wafer surface is extended, the electrostatic energy that was originally released instantaneously is dispersed into millisecond-level smooth dissipation, the peak current is limited within the device safety threshold, the generation of high voltage electrostatic discharge pulses is eliminated from the source, the nanoscale sensitive devices on the wafer are prevented from being electrostatically damaged, and the chip production yield is improved.

[0037] In one embodiment, the resistance value of the current-limiting resistor 8 is fixed. A current-limiting resistor 8 with a fixed resistance value, such as 1MΩ, is connected in series between the conductive support and the relay 5. The current-limiting resistor 8 can effectively limit the peak current that may occur during discharge, making the charge discharge process smoother and further eliminating the potential risk of spark discharge or transient current surge.

[0038] In another embodiment, the current-limiting resistor 8 is a precision resistor with adjustable resistance. It can dynamically match the resistance value based on the amount of residual electrostatic charge on the wafer surface collected in real time, and adaptively adjust the RC time constant of the discharge circuit. This allows the electrostatic discharge rate under different process conditions to be accurately matched with the current path characteristics. Under the premise of ensuring complete electrostatic discharge, the transient current is strictly controlled within the safe threshold of the wafer device throughout the process, and the risks of high voltage electrostatic discharge pulses and spark discharges are completely avoided.

[0039] In one embodiment, the control module 7 further includes an electrostatic detection unit for monitoring the current value of the relay 5.

[0040] The control module 7 integrates or connects an external electrostatic discharge (ESD) detection unit, such as a non-contact surface potential method probe, to monitor the current value of relay 5 in real time. The control module 7 then transmits the obtained current value to the control module 7. Based on the current value obtained from the ESD detection unit, the control module 7 determines whether the discharge current is within a preset discharge safety threshold, or whether it exceeds an instantaneous safety threshold. This information is used to determine whether chip removal is possible and to avoid potential spark discharge or transient current surge risks.

[0041] In one embodiment, the conductive lifting pin 3 is made of a conductive material with a smooth, rounded tip. The tip of the conductive lifting pin 3 is covered with a layer of conductive elastic material, such as conductive rubber or conductive sponge. The conductive material provides a low-impedance direct path to ground for residual adsorbed charges, enabling millisecond-level rapid and complete discharge of residual static electricity; the smooth, rounded tip avoids problems such as wafer warping and cracking caused by uneven lifting force.

[0042] like Figure 3 As shown, this embodiment also provides a wafer de-adsorption method, which is based on the above-described wafer de-adsorption device and includes the following steps: During the wafer adsorption and processing stage, the robotic arm delivers wafer 1 into the chamber and places it on the raised conductive lifting pin 3. Subsequently, the conductive lifting pin 3 descends, allowing wafer 1 to smoothly adhere to the surface of the electrostatic chuck 2. At this time, the control module 7 ensures that relay 5 is in the off state. Next, the control module 7 controls the electrostatic chuck 2 to apply high-voltage DC current, firmly adsorbing wafer 1. This process continues until the next processing stage, during which relay 5 remains off.

[0043] After the process stage is completed, the control module 7 cuts off the high-voltage DC power applied to the electrostatic chuck 2; After a delay of S1, the control module 7 outputs a signal to close the relay 5. The control module 7 then controls the lifting drive mechanism 4 to drive the conductive lifting pin 3 to move upward. The conductive lifting pin 3 rises to the position of contacting the back of the wafer. The residual static electricity of the wafer 1 and the electrostatic chuck 2 is discharged through the conductive lifting pin 3, the conductive support base, the relay 5, and the grounding terminal 6. After the residual electrostatic discharge time S2, the control module 7 controls the conductive lifting pin 3 to rise to the wafer picking position, smoothly lifting the wafer 1, which is no longer electrostatically attracted, off the surface of the electrostatic chuck 2, where it is then picked up by the robotic arm. After wafer picking is completed, the control module 7 controls the relay 5 to disconnect.

[0044] This invention is applicable to processes such as etching and thin film deposition. Utilizing the direct physical contact between the conductive lifting pin and the back of the wafer, and its connection to the electrostatic chuck, it provides a low-impedance direct path to ground for residual adsorbed charges. This enables millisecond-level rapid and complete discharge of residual static electricity, completely eliminating the residual adsorption force of the electrostatic chuck on the wafer. Through logic timing control by the control module, the conduction window of the discharge path is strictly limited to the wafer desorption stage after the electrostatic chuck is de-energized. During wafer adsorption and the process stage, the discharge path remains completely disconnected, completely severing the coupling between the discharge path and the internal electric field of the electrostatic chuck. The complete isolation of the discharge path during wafer adsorption and the process stage will not cause any disturbance to the electrostatic adsorption electric field or the plasma process electric field inside the electrostatic chuck. Simultaneously, the arc-shaped top design of the conductive lifting pin 3 evenly disperses the force during the lifting process, effectively protecting the structural integrity of the back of the wafer.

[0045] In another embodiment, such as Figure 4 As shown, a wafer desorption method, based on the above-described wafer desorption apparatus, includes the following steps: During the wafer adsorption and processing stage, the robotic arm delivers wafer 1 into the chamber and places it on the raised conductive lifting pin 3. Subsequently, the conductive lifting pin 3 descends, allowing wafer 1 to smoothly adhere to the surface of the electrostatic chuck 2. At this time, the control module 7 ensures that relay 5 is in the off state. Next, the control module 7 controls the electrostatic chuck 2 to apply high-voltage DC current, firmly adsorbing wafer 1. This process continues until the next processing stage, during which relay 5 remains off.

[0046] After the process stage is completed, the control module 7 cuts off the high-voltage DC power applied to the electrostatic chuck 2; After a delay of S1, the control module 7 outputs a signal to close the relay 5. The control module 7 then controls the lifting drive mechanism 4 to drive the conductive lifting pin 3 to move upward. The conductive lifting pin 3 rises to the position of contacting the back of the wafer. The residual static electricity of the wafer 1 and the electrostatic chuck 2 is discharged through the conductive lifting pin 3, the conductive support base, the relay 5, and the grounding terminal 6. During residual electrostatic discharge, control module 7 controls the electrostatic detection unit to monitor the current value of relay 5 and determine whether the current value has dropped below the preset discharge safety threshold. If so, control module 7 controls the lifting drive mechanism 4 to drive the conductive lifting pin 3 upward; otherwise, discharge continues. After relay 5 closes to begin discharge, the current value is continuously monitored. Only when the monitored current value drops below the preset discharge safety threshold is the subsequent control module 7 triggered to control the lifting drive mechanism 4 to drive the conductive lifting pin 3 upward to the wafer pickup position, completing wafer pickup. This feedback control based on the actual electrostatic discharge effect is more accurate and reliable than fixed time delay control and can adapt to changes in residual electrostatic discharge under different process conditions.

[0047] In another embodiment, such as Figure 5 As shown, a wafer desorption method, based on the above-described wafer desorption apparatus, includes the following steps: During the wafer adsorption and processing stage, the robotic arm delivers wafer 1 into the chamber and places it on the raised conductive lifting pin 3. Subsequently, the conductive lifting pin 3 descends, allowing wafer 1 to smoothly adhere to the surface of the electrostatic chuck 2. At this time, the control module 7 ensures that relay 5 is in the off state. Next, the control module 7 controls the electrostatic chuck 2 to apply high-voltage DC current, firmly adsorbing wafer 1. This process continues until the next processing stage, during which relay 5 remains off.

[0048] After the process stage is completed, the control module 7 cuts off the high-voltage DC power applied to the electrostatic chuck 2; After a delay of S1, the control module 7 outputs a signal to close the relay 5. The control module 7 then controls the lifting drive mechanism 4 to drive the conductive lifting pin 3 to move upward. The conductive lifting pin 3 rises to the position of contacting the back of the wafer. The residual static electricity of the wafer 1 and the electrostatic chuck 2 is discharged through the conductive lifting pin 3, the conductive support base, the relay 5, and the grounding terminal 6. During residual static electricity discharge, control module 7 controls the static electricity detection unit to monitor the current value of relay 5 and determine whether the current value exceeds the discharge safety threshold. If so, the control module controls the current-limiting resistor to increase its resistance value to reduce the peak current. The current-limiting resistor can effectively limit the peak current that may occur during discharge, making the residual static electricity discharge process smoother and further eliminating the potential risk of spark discharge or transient current surge.

[0049] After the residual electrostatic discharge time S2, the control module 7 controls the conductive lifting pin 3 to rise to the wafer picking position, smoothly lifting the wafer 1, which is no longer electrostatically attracted, off the surface of the electrostatic chuck 2, where it is then picked up by the robotic arm. After wafer picking is completed, the control module 7 controls the relay 5 to disconnect.

[0050] In another embodiment, such as Figure 6 As shown, a wafer desorption method, based on the above-described wafer desorption apparatus, includes the following steps: During the wafer adsorption and processing stage, the robotic arm delivers wafer 1 into the chamber and places it on the raised conductive lifting pin 3. Subsequently, the conductive lifting pin 3 descends, allowing wafer 1 to smoothly adhere to the surface of the electrostatic chuck 2. At this time, the control module 7 ensures that relay 5 is in the off state. Next, the control module 7 controls the electrostatic chuck 2 to apply high-voltage DC current, firmly adsorbing wafer 1. This process continues until the next processing stage, during which relay 5 remains off.

[0051] After the process stage is completed, the control module 7 cuts off the high-voltage DC power applied to the electrostatic chuck 2; After a delay of S1, the control module 7 outputs a signal to close the relay 5. The control module 7 then controls the lifting drive mechanism 4 to drive the conductive lifting pin 3 to move upward. The conductive lifting pin 3 rises to the position of contacting the back of the wafer. The residual static electricity of the wafer 1 and the electrostatic chuck 2 is discharged through the conductive lifting pin 3, the conductive support base, the relay 5, and the grounding terminal 6. During residual static electricity discharge, control module 7 controls the static electricity detection unit to monitor the current value of relay 5 and determine whether the current value exceeds the discharge safety threshold. If so, the control module controls the current-limiting resistor to increase its resistance value to reduce the peak current. The current-limiting resistor can effectively limit the peak current that may occur during discharge, making the residual static electricity discharge process smoother and further eliminating the potential risk of spark discharge or transient current surge.

[0052] During residual electrostatic discharge, control module 7 controls the electrostatic detection unit to monitor the current value of relay 5 and determine whether the current value has dropped below the preset discharge safety threshold. If so, control module 7 controls the lifting drive mechanism 4 to drive the conductive lifting pin 3 upward; otherwise, discharge continues. After relay 5 closes to begin discharge, the current value is continuously monitored. Only when the monitored current value drops below the preset discharge safety threshold is the subsequent control module 7 triggered to control the lifting drive mechanism 4 to drive the conductive lifting pin 3 upward to the wafer pickup position, completing wafer pickup. This feedback control based on the actual electrostatic discharge effect is more accurate and reliable than fixed time delay control and can adapt to changes in residual electrostatic discharge under different process conditions.

[0053] In another embodiment, the delay time S1 is 50-200ms to ensure that the high voltage is completely removed; the residual static discharge time S2 is 400-900ms to ensure that the charge is fully discharged.

[0054] This embodiment also provides a semiconductor device, including the aforementioned wafer desorption device. The semiconductor device in this embodiment can be an etching device, a thin film deposition device, an ion implantation device, or a cleaning device, etc. By integrating the aforementioned wafer desorption device, this semiconductor device can effectively solve the problem of electrostatic residue during the wafer desorption stage, significantly improving the reliability of wafer transport and the operating efficiency of the equipment. The above semiconductor device does not require major modifications to the core structure of the existing electrostatic chuck, such as electrodes and dielectric layers; the main changes are in upgrading the conductive lifting pins and adding a control unit, making it easy to implement on existing equipment and highly compatible.

[0055] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A wafer de-adsorption device, characterized in that, include: The system comprises an electrostatic chuck, a conductive lifting pin, a conductive support base, a lifting drive mechanism, a relay, a grounding terminal, and a control module. The electrostatic chuck carries and secures a wafer. The top of the conductive lifting pin passes through a through-hole in the electrostatic chuck, contacting and lifting the wafer. The bottom end of the conductive lifting pin is fixedly connected to the conductive support base and conducts electricity through the electrostatic chuck. One end of the relay is electrically connected to the conductive support base, and the other end is connected to the grounding terminal. The control module controls the lifting drive mechanism to drive the conductive lifting pin to move up and down. The control module also controls the on / off state of the DC current applied to the electrostatic chuck. Furthermore, the control module controls the on / off state of the relay, thereby controlling the grounding state of the conductive lifting pin.

2. The wafer de-adsorption device according to claim 1, characterized in that, A current-limiting resistor is connected in series between the conductive support base and the relay.

3. The wafer de-adsorption device according to claim 2, characterized in that, The current-limiting resistor is either a resistor with a fixed resistance or a resistor with an adjustable resistance.

4. The wafer de-adsorption device according to claim 1, characterized in that, The control module also includes an electrostatic detection unit for monitoring the current value of the relay.

5. The wafer de-adsorption device according to claim 1, characterized in that, The conductive lifting pin is made of conductive material and has a smooth, rounded top.

6. A wafer de-adsorption method, characterized in that, The wafer de-adsorption apparatus according to any one of claims 1-5 includes the following steps: During the wafer adsorption and processing stages, the relay remains in the off state; After the process stage is completed, the control module cuts off the DC power applied to the electrostatic chuck; After a delay of S1, the control module controls the relay to close, and the control module controls the lifting drive mechanism to drive the conductive lifting pin to move upward to the position of contacting the back of the wafer; the residual static electricity of the wafer and the electrostatic chuck is discharged through the conductive lifting pin, the conductive support base, the relay and the grounding terminal; After the residual static discharge time S2, the control module controls the conductive lifting pin to rise to the wafer retrieval position. After wafer retrieval is completed, the control module controls the relay to disconnect.

7. The wafer de-adsorption method according to claim 6, characterized in that, During the discharge of residual static electricity, the control module controls the static electricity detection unit to monitor the current value of the relay and determine whether the current value has dropped to within the preset discharge safety threshold. If so, the control module controls the lifting drive mechanism to drive the conductive lifting pin to move upward. If not, the discharge continues.

8. The wafer desorption method according to claim 6 or 7, characterized in that, During the residual static discharge, the control module controls the static detection unit to monitor the current value of the relay and determine whether the current value exceeds the instantaneous safety threshold. If so, the control module controls the current limiting resistor to increase its resistance value to reduce the peak current.

9. The wafer de-adsorption method according to claim 6, characterized in that, The delay time S1 is 50-200ms, and the residual static electricity discharge time S2 is 400-900ms.

10. A semiconductor device, characterized in that, Includes the wafer desorption device as described in any one of claims 1-5.

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