A contactless electrostatic levitation support system and method

Abstract

The application relates to the technical field of semiconductor manufacturing equipment, and particularly provides a non-contact electrostatic suspension support system and method. The system comprises a process chamber, a suspension electrode, an inert gas supply assembly, a temperature monitoring assembly and a controller. After a wafer to be processed is placed on the suspension electrode, the controller applies a first preset alternating voltage to the suspension electrode to generate an electric field between the wafer to be processed and the suspension electrode and make the wafer to be processed float, then controls the inert gas supply assembly to supply a preset flow of inert gas to each gas outlet to form a fluid isolation layer between the wafer and the suspension electrode, and during process execution, the controller acquires real-time temperature distribution information of the wafer to be processed by using the temperature monitoring assembly, and adjusts the inert gas flow of the gas outlet according to the deviation between the real-time temperature distribution information and a preset target temperature. The system can effectively avoid metal ion pollution, particle pollution and thermal stress damage caused by a traditional support mode.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing equipment technology, and more specifically, to a contactless electrostatic levitation support system and method. Background Technology

[0002] In high-temperature industrial equipment (such as semiconductor annealing furnaces, glass heat treatment furnaces, and photovoltaic diffusion furnaces), the preset target temperature typically reaches 1000-1300℃. These equipment uses quartz boats or quartz supports to hold the wafers. These supports face significant technical bottlenecks during high-temperature cycling: First, quartz releases metallic impurities such as sodium, potassium, and iron at high temperatures. These impurities diffuse onto the wafer surface, leading to deterioration of the device's electrical performance and a decrease in yield. Second, microcracks develop on the quartz surface under thermal stress, and the released quartz particles adhere to the wafer surface, forming defects. Third, localized stress concentrations at mechanical contact points can cause wafer warping, slip dislocations, and even breakage. Finally, quartz degrades in performance after aging, requiring frequent replacement and recalibration, severely impacting production stability. These problems significantly restrict the improvement of precision and yield in semiconductor manufacturing processes.

[0003] There is currently no effective technical solution to the above problems. Summary of the Invention

[0004] The purpose of this application is to provide a non-contact electrostatic levitation support system and method that can effectively avoid metal ion contamination, particulate contamination and thermal stress damage caused by traditional support methods.

[0005] In a first aspect, this application provides a contactless electrostatic levitation support system, comprising:

[0006] Process chambers;

[0007] The suspended electrode is installed inside the process chamber;

[0008] Multiple air outlets are arranged in a circular array on the suspended electrode;

[0009] Inert gas supply assembly, connected to all gas outlets;

[0010] Temperature monitoring components;

[0011] The controller is used to apply a first preset AC voltage to the suspension electrode after the wafer to be processed is placed on the suspension electrode, so as to generate an electric field between the wafer to be processed and the suspension electrode and make the wafer to be processed float. Then, it controls the inert gas supply component to supply a preset flow rate of inert gas to each gas outlet to form a fluid isolation layer between the wafer and the suspension electrode. It is also used to acquire real-time temperature distribution information of the wafer to be processed using a temperature monitoring component during the process execution, and adjust the inert gas flow rate of the gas outlet according to the deviation between the real-time temperature distribution information and the preset target temperature. The frequency of the first preset AC voltage is 1-10kHz.

[0012] This application provides a contactless electrostatic levitation support system that fundamentally eliminates the physical contact between the wafer and the support through contactless levitation technology. Therefore, this application can effectively avoid metal ion contamination, particulate contamination and thermal stress damage caused by traditional support methods.

[0013] Optionally, the contactless electrostatic levitation support system further includes an edge stabilizing electrode, which is sleeved outside the levitation electrode and the distance between the edge stabilizing electrode and the levitation electrode is greater than 0. The controller is also used to apply a second preset AC voltage to the edge stabilizing electrode before applying a first preset AC voltage to the levitation electrode, wherein the phase difference between the first preset AC voltage and the second preset AC voltage is 90°.

[0014] Optionally, the non-contact electrostatic levitation support system also includes a spacing adjustment component and a levitation height acquisition component. The controller is also used to determine the spacing adjustment amount based on the height deviation when the absolute value of the height deviation between the actual overall levitation height of the wafer to be processed and the preset target levitation height is greater than a first preset threshold, and to determine the AC voltage adjustment amount based on the spacing adjustment amount. Then, the controller controls the spacing adjustment component to adjust the spacing between the edge stabilizing electrode and the levitation electrode based on the spacing adjustment amount, and adjusts the voltage amplitude of the second preset AC voltage based on the AC voltage adjustment amount.

[0015] Optionally, the levitation electrode is divided into multiple levitation regions, and the actual overall levitation height is the average of the actual levitation heights corresponding to all levitation regions. The controller is also used to analyze whether the wafer to be processed is in a horizontal position based on all actual levitation heights. When the analysis indicates that the wafer to be processed is not in a horizontal position, the controller is also used to determine the height abnormal region based on all actual levitation heights, and then control the levitation electrode to adjust the voltage amplitude of the height abnormal region until the wafer to be processed returns to a horizontal position. The height abnormal region is the levitation region where the absolute value of the difference between the actual levitation height and the actual overall levitation height is greater than a second preset threshold.

[0016] Optionally, each suspended region corresponds to at least one air outlet. The real-time temperature distribution information includes the real-time temperature of each suspended region. The process of adjusting the inert gas flow rate at the air outlet based on the deviation between the real-time temperature distribution information and the preset target temperature includes:

[0017] B1. Determine the temperature anomaly area based on real-time temperature distribution information and preset target temperature; the temperature anomaly area is a floating area where the real-time temperature is different from the preset target temperature.

[0018] B2. Determine the flow adjustment amount corresponding to the temperature anomaly area based on the deviation between the real-time temperature of the temperature anomaly area and the preset target temperature.

[0019] B3. Analyze whether the sum of the inert gas flow rate and the flow rate adjustment amount corresponding to the temperature anomaly area is greater than the upper limit of the preset flow rate range or less than the lower limit of the preset flow rate range. If yes, proceed to step B4 or B5. If no, adjust the inert gas flow rate of the outlet corresponding to the temperature anomaly area according to the flow rate adjustment amount corresponding to the temperature anomaly area. The preset flow rate is within the preset flow rate range.

[0020] B4. When the sum of the inert gas flow rate and flow adjustment amount in the abnormal temperature zone is greater than the upper limit of the preset flow range, analyze whether the inert gas flow rate in the normal temperature zone is less than or equal to the lower limit of the preset flow range. If yes, generate an alarm message. If no, take the difference between the upper limit of the preset flow range and the inert gas flow rate in the abnormal temperature zone as the flow adjustment amount in the abnormal temperature zone, and take the negative of the difference between the sum of the inert gas flow rate and flow adjustment amount in the abnormal temperature zone and the upper limit of the preset flow range as the flow adjustment amount in the normal temperature zone. Then adjust the inert gas flow rate in the abnormal temperature zone according to the flow adjustment amount in the abnormal temperature zone, and adjust the inert gas flow rate in the normal temperature zone according to the flow adjustment amount in the normal temperature zone.

[0021] B5. When the sum of the inert gas flow rate and flow adjustment amount corresponding to the abnormal temperature zone is less than the lower limit of the preset flow range, analyze whether the inert gas flow rate corresponding to the normal temperature zone has reached the upper limit of the preset flow range. If yes, generate an alarm message. If no, take the difference between the lower limit of the preset flow range and the inert gas flow rate corresponding to the abnormal temperature zone as the flow adjustment amount corresponding to the abnormal temperature zone, and take the negative of the difference between the sum of the inert gas flow rate and flow adjustment amount corresponding to the abnormal temperature zone and the lower limit of the preset flow range as the flow adjustment amount corresponding to the normal temperature zone. Then adjust the inert gas flow rate corresponding to the abnormal temperature zone according to the flow adjustment amount corresponding to the abnormal temperature zone, and adjust the inert gas flow rate corresponding to the normal temperature zone according to the flow adjustment amount corresponding to the normal temperature zone.

[0022] Optionally, after the wafer to be processed is placed on the levitation electrode, a first preset AC voltage is applied to the levitation electrode to generate an electric field between the wafer to be processed and the levitation electrode and to make the wafer to be processed float. Then, the inert gas supply assembly is controlled to supply a preset flow rate of inert gas to each gas outlet to form a fluid isolation layer between the wafer and the levitation electrode.

[0023] A1. Obtain the material thermal conductivity information, thickness information, and surface patterning feature data of the wafer to be processed;

[0024] A2. Input the material thermal conductivity information, thickness information and surface patterning feature data into the pre-trained wafer thermal model so that the wafer thermal model outputs the predicted wafer temperature gradient information;

[0025] A3. Based on the predicted wafer temperature gradient information, extract the corresponding AC voltage as the first preset AC voltage from the pre-constructed mapping table of wafer temperature gradient and its corresponding AC voltage and gas flow rate combination, and extract the corresponding gas flow rate as the preset flow rate.

[0026] A4. After the wafer to be processed is placed on the levitation electrode, a first preset AC voltage is applied to the levitation electrode to generate an electric field between the wafer to be processed and the levitation electrode and to make the wafer to be processed float. Then, the inert gas supply component is controlled to supply a preset flow rate of inert gas to each gas outlet to form a fluid isolation layer between the wafer and the levitation electrode.

[0027] Optionally, the non-contact electrostatic levitation support system also includes a temperature compensation electrode, which is located below the levitation electrode and is used to compensate the temperature of the wafer to be processed.

[0028] Optionally, the non-contact electrostatic levitation support system also includes a preheating unit, which is located between the inert gas supply component and the gas outlet. The preheating unit is used to heat the inert gas supplied by the inert gas supply component to a preset temperature, which is lower than a preset target temperature.

[0029] Optionally, the preset temperature is 200-400℃.

[0030] Secondly, this application also provides a non-contact electrostatic levitation support method, which is applied to the non-contact electrostatic levitation support system provided in the first aspect above, and the method includes the following steps:

[0031] S1. After the wafer to be processed is placed on the levitation electrode, a first preset AC voltage is applied to the levitation electrode to generate an electric field between the wafer to be processed and the levitation electrode and to make the wafer to be processed float. Then, the inert gas supply component is controlled to supply a preset flow rate of inert gas to each gas outlet to form a fluid isolation layer between the wafer and the levitation electrode. The frequency of the first preset AC voltage is 1-10kHz.

[0032] S2. During the process, the temperature monitoring component is used to obtain the real-time temperature distribution information of the wafer to be processed, and the inert gas flow rate at the outlet is adjusted according to the deviation between the real-time temperature distribution information and the preset target temperature.

[0033] This application provides a non-contact electrostatic levitation support method, which fundamentally eliminates the physical contact between the wafer and the support through non-contact levitation technology. Therefore, this application can effectively avoid metal ion contamination, particulate contamination and thermal stress damage caused by traditional support methods.

[0034] As can be seen from the above, the contactless electrostatic levitation support system and method provided in this application fundamentally eliminates the physical contact between the wafer and the support through contactless levitation technology. Therefore, this application can effectively avoid metal ion contamination, particulate contamination and thermal stress damage caused by traditional support methods. Attached Figure Description

[0035] Figure 1 This is a structural schematic diagram of a contactless electrostatic levitation support system provided in an embodiment of this application.

[0036] Figure 2 This is a top view of the suspended electrode provided in an embodiment of this application.

[0037] Figure 3 This is a schematic diagram of the connection relationship of a contactless electrostatic levitation support system provided in an embodiment of this application.

[0038] Figure 4 A flowchart of a non-contact electrostatic levitation support method provided in an embodiment of this application.

[0039] Reference numerals: 1. Process chamber; 2. Suspended electrode; 3. Gas outlet; 4. Inert gas supply assembly; 5. Temperature monitoring assembly; 6. Controller; 7. Edge stabilizing electrode; 8. Spacing adjustment assembly; 9. Suspension height acquisition assembly; 10. Temperature compensation electrode; 11. Preheating unit. Detailed Implementation

[0040] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0041] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0042] Firstly, such as Figures 1-3 As shown, this application provides a contactless electrostatic levitation support system, which includes:

[0043] Process chamber 1;

[0044] Suspended electrode 2 is disposed inside process chamber 1;

[0045] Multiple air outlets 3 are arranged in a circular array on the suspended electrode 2;

[0046] Inert gas supply assembly 4 is connected to all gas outlets 3;

[0047] Temperature monitoring component 5;

[0048] The controller 6 is used to apply a first preset AC voltage to the suspension electrode 2 after the wafer to be processed is placed on the suspension electrode 2, so as to generate an electric field between the wafer to be processed and the suspension electrode 2 and make the wafer to be processed float. Then, it controls the inert gas supply component 4 to supply inert gas at a preset flow rate to each gas outlet 3 to form a fluid isolation layer between the wafer and the suspension electrode 2. It is also used to obtain the real-time temperature distribution information of the wafer to be processed using the temperature monitoring component 5 during the process execution, and adjust the inert gas flow rate of the gas outlet 3 according to the deviation between the real-time temperature distribution information and the preset target temperature. The frequency of the first preset AC voltage is 1-10kHz.

[0049] For ease of understanding, some key terms in this embodiment are explained below. The process chamber 1 in this embodiment refers to a sealed space used for high-temperature processing of the wafer under controlled conditions to prevent interference from the external environment. It should be understood that the process chamber 1 in this embodiment is preferably an existing chamber in semiconductor manufacturing processes, and its specific structure and working principle will not be discussed in detail here. The levitation electrode 2 in this embodiment refers to an electrode disposed within the process chamber 1. In this embodiment, a strong electric field is formed between the wafer under processing and the levitation electrode 2 by applying a high-frequency AC voltage. The Coulomb force and Johnson-Rabec effect generated by the strong electric field levitate the wafer under processing (at this time, there is a gap between the wafer under processing and the levitation electrode 2). The levitation electrode 2 in this embodiment has multiple air outlets 3, which are arranged in a circumferential array around the center of the levitation electrode 2. These air outlets 3 allow inert gas to flow into the gap between the wafer under processing and the levitation electrode 2. It should be understood that this embodiment is equivalent to non-contact levitation of the wafer under processing to avoid contamination and stress damage caused by mechanical support. In this embodiment, the inert gas supply component 4 is a device connected to all the gas outlets 3 on the levitation electrode 2. This component supplies inert gas at a preset flow rate (equivalent to a preset initial value of the inert gas flow rate supplied to the outlets 3) to form a fluid isolation layer between the wafer to be processed and the levitation electrode 2, thereby preventing wafer contamination. The temperature monitoring component 5 in this embodiment is a device for acquiring real-time temperature distribution information of the wafer to be processed. Preferably, the temperature monitoring component 5 employs non-contact temperature measurement technology (such as infrared thermometry) to ensure accurate acquisition of wafer temperature data in high-temperature environments and without contact with the wafer. This temperature detection component is preferably an existing multi-point infrared thermometry array, the working principle of which will not be discussed in detail here. The controller 6 in this embodiment refers to the core control unit of the entire system, responsible for coordinating and managing the operation of each component. Its functions include applying AC voltage to levitate the wafer, controlling the inert gas flow rate, and adjusting the gas flow rate according to temperature information to ensure the stability of the process and the temperature uniformity of the wafer.

[0050] This application proposes a contactless electrostatic levitation support system, which includes a process chamber 1, a levitation electrode 2, an inert gas supply component 4, a temperature monitoring component 5, and a controller 6. Specifically, the levitation electrode 2 is disposed within the process chamber 1 and has multiple gas outlets 3 arranged in a circumferential array on it. Since the spacing between adjacent gas outlets 3 is the same, this embodiment can ensure that the inert gas entering the gap between the wafer to be processed and the levitation electrode 2 uniformly covers the bottom of the wafer to be processed. It should be understood that the number and distribution density of the gas outlets 3 can be designed according to the size of the wafer to be processed and the process requirements. For example, for a wafer with a diameter of 300 mm, 10-20 gas outlets 3 can be provided. The inert gas supply component 4 of this embodiment is connected to all gas outlets 3. This component is used to supply inert gas to these gas outlets 3. The inert gas in this embodiment can be nitrogen, argon, or helium, etc., and the flow rate of the inert gas supplied to each gas outlet 3 can be precisely controlled by a flow meter. In this embodiment, the controller 6 applies a first preset AC voltage to the levitation electrode 2 after the wafer to be processed is placed on the levitation electrode 2 (this embodiment can be done manually or using a robotic arm). The frequency of the first preset AC voltage is 1-10kHz. For example, this embodiment can apply an AC voltage with a frequency of 5kHz and a voltage amplitude of 1kV to the levitation electrode 2. This embodiment generates an electric field between the wafer to be processed and the levitation electrode 2 by applying an AC voltage to the levitation electrode 2, causing the wafer to float and thus achieving contactless support. After the wafer floats, the controller 6 controls the inert gas supply component 4 to supply a preset flow rate of inert gas to each outlet 3. This inert gas forms a fluid isolation layer between the wafer to be processed and the levitation electrode 2, further preventing contact between the wafer and the electrode surface and blocking the diffusion of metal ions. During process execution, the controller 6 uses a temperature monitoring component 5 to obtain real-time temperature distribution information of the wafer to be processed. This temperature monitoring component 5 can be an infrared temperature measurement array to obtain temperature data of multiple points on the wafer surface in real time. The controller 6 adjusts the inert gas flow rate at the outlet 3 based on the deviation between the real-time temperature distribution information and the preset target temperature. For example, if the real-time temperature of a certain area is higher than the preset target temperature, the controller 6 can increase the inert gas flow rate at the corresponding outlet 3 in that area to reduce the local temperature through the cooling effect of the gas. Conversely, if the real-time temperature of a certain area is lower than the preset target temperature, the controller 6 can reduce the inert gas flow rate at the corresponding outlet 3 in that area to increase the local temperature. This dynamic adjustment mechanism ensures that the wafer maintains a uniform temperature distribution throughout the entire process.

[0051] The following example provides a more detailed explanation of the above technical solution: Suppose that in a semiconductor annealing process, a silicon wafer with a diameter of 300 mm needs to be subjected to high-temperature treatment at a target temperature of 1100℃. Traditional support methods may lead to problems such as metal ion contamination, particulate contamination, thermal stress damage, and poor process repeatability at high temperatures. To solve these problems, the contactless electrostatic levitation support system of this application is applied to this annealing process. First, the silicon wafer to be processed (the wafer to be processed) is placed above the levitation electrode 2 in the process chamber 1. The controller 6 is activated and applies a first preset AC voltage with a frequency of 5 kHz and a voltage amplitude of 1.5 kV to the levitation electrode 2. This AC voltage generates an electrostatic field between the bottom of the wafer and the levitation electrode 2, causing the silicon wafer to slowly float under the action of the electric field force, maintaining a small gap, for example, 100 μm, between it and the levitation electrode 2. At this time, contactless operation is achieved between the silicon wafer and the support structure, avoiding contamination and stress caused by mechanical contact. After the wafer is stably suspended, the controller 6 further controls the inert gas supply component 4 to supply a preset flow rate of inert gas, such as high-purity nitrogen at a flow rate of 30 L / min, to the bottom of the wafer through multiple gas outlets 3 arranged in a circumferential array on the suspension electrode 2. This nitrogen forms a stable fluid isolation layer between the silicon wafer and the suspension electrode 2. This isolation layer not only further ensures the physical isolation between the silicon wafer and the suspension electrode 2, but also effectively blocks the diffusion of metal ions that may be present in the electrode material to the wafer surface, while preventing the adhesion of microparticles. As the annealing process proceeds, the wafer gradually heats up. The temperature monitoring component 5 acquires the temperature distribution information of the silicon wafer surface in real time. Suppose that at a certain moment, the temperature monitoring component 5 detects that the real-time temperature of one area of ​​the wafer is 1110℃, while the real-time temperature of another area is 1090℃, and the preset target temperature is 1100℃. After receiving this real-time temperature distribution information, the controller 6 will identify the situation where the temperature in the central area is too high and the temperature in the edge area is too low. Based on these temperature deviations, the controller 6 will dynamically adjust the inert gas flow rate of the corresponding gas outlet 3. Specifically, for the region with a real-time temperature of 1110℃, since the real-time temperature is higher than the target temperature, the controller 6 increases the nitrogen flow rate at the corresponding outlet 3 in that region, for example, increasing the flow rate from 30L / min to 35L / min. The increased nitrogen flow rate will remove more heat, thereby lowering the temperature in that region. For the region with a real-time temperature of 1090℃, since the real-time temperature is lower than the target temperature, the controller 6 reduces the nitrogen flow rate at the corresponding outlet 3 in that region, for example, reducing the flow rate from 30L / min to 25L / min. The reduced nitrogen flow rate will decrease heat loss in that region, thereby increasing the temperature in that region. Through this precise local gas flow rate adjustment, the controller 6 can continuously adjust the real-time temperature distribution of the wafer to be close to the preset target temperature, ensuring that the wafer maintains a high degree of temperature uniformity throughout the annealing process.

[0052] As can be seen from the above examples, the contactless electrostatic levitation support system of this application fundamentally eliminates the physical contact between the wafer and the support through contactless levitation technology, effectively avoiding metal ion contamination, particulate contamination, and thermal stress damage caused by traditional support methods. Compared with the problem of traditional quartz boats or quartz supports releasing impurities and particles at high temperatures, this system utilizes an electrostatic field and an inert gas fluid isolation layer to achieve pure wafer support. In addition, this system introduces a temperature monitoring component 5 and a controller 6, which can acquire the temperature distribution information of the wafer in real time and dynamically adjust the inert gas flow rate according to the temperature deviation. This closed-loop control mechanism enables the wafer to maintain a high degree of temperature uniformity in high-temperature processes, significantly improving the stability and repeatability of the process, and solving the problems of performance degradation due to quartz aging and the need for frequent replacement and calibration in traditional solutions. Therefore, the technical solution of this application has made significant technical contributions to improving wafer processing quality, reducing contamination risks, and improving process stability.

[0053] In some preferred embodiments, the contactless electrostatic levitation support system further includes an edge stabilizing electrode 7, which is sleeved outside the levitation electrode 2 and has a distance greater than 0 between it and the levitation electrode 2. The controller 6 is further configured to apply a second preset AC voltage to the edge stabilizing electrode 7 before applying a first preset AC voltage to the levitation electrode 2, wherein the phase difference between the first preset AC voltage and the second preset AC voltage is 90°. In this embodiment, the edge stabilizing electrode 7 is an auxiliary electrode whose main function is to generate an additional electric field in the edge region of the wafer to be processed, thereby enhancing the stability of the wafer during levitation. The edge stabilizing electrode 7 can be designed as a ring structure, concentrically arranged with the levitation electrode 2, or composed of multiple segmented arc-shaped electrode arrays uniformly arranged around the levitation electrode 2. The material of the edge stabilizing electrode 7 is preferably a material with good conductivity and high temperature resistance (e.g., doped silicon or a specific metal alloy), and embedded in an insulating substrate such as ceramic or quartz. In this embodiment, the edge stabilizing electrode 7 is sleeved outside the levitation electrode 2 and has a distance greater than 0 between it and the levitation electrode 2 to ensure that the edge stabilizing electrode 7 can independently generate an electric field while avoiding physical contact between the edge stabilizing electrode 7 and the levitation electrode 2. The controller 6 in this embodiment is also used to apply a second preset AC voltage to the edge stabilizing electrode 7 before applying a first preset AC voltage to the levitation electrode 2. That is, in actual operation, the program logic inside the controller 6 can be set to activate the power module of the edge stabilizing electrode 7 first when the levitation process is started, so that it outputs voltage before the levitation electrode 2. This mechanism of applying voltage in advance is intended to establish a stable electric field in the edge region of the wafer in advance, providing a pre-existing edge constraint for the initial levitation of the wafer, thereby effectively preventing the wafer from undergoing undesirable horizontal movement due to inertia or external disturbances in the early stage of levitation. In this embodiment, the phase difference between the first preset AC voltage and the second preset AC voltage is 90°. This phase difference can be achieved by two independent AC power supplies, whose output signals are adjusted by a precise phase controller to ensure a 90° phase difference. Alternatively, this embodiment can also directly provide two outputs with a 90° phase difference through a multiphase AC power supply. For example, one voltage can be V0*sin(ωt), and the other voltage can be V0*sin(ωt+π / 2). This 90° phase difference utilizes the phase orthogonality of the electric field, which can form a gradient electric field in the wafer edge region. When the wafer shifts, the electric field force in the edge region will generate a reverse correction force, pulling the wafer back to the center position, thereby synergistically suppressing the overall vibration and rotation trend of the wafer and significantly enhancing the dynamic stability of the suspension. Preferably, this embodiment can adjust the voltage amplitude of the edge stabilizing electrode 7 according to the real-time edge position of the wafer to be processed. For example, when the real-time edge position of the edge to be processed is not symmetrical with respect to the suspension electrode 2, the voltage amplitude of the edge stabilizing electrode 7 is increased to increase the reverse correction force.

[0054] This embodiment effectively solves the problem of wafer edge instability during levitation by introducing an edge stabilizing electrode 7 into a contactless electrostatic levitation support system and applying an AC voltage with a specific timing and phase relationship to it. Specifically, after the wafer to be processed is placed on the levitation electrode 2, the controller 6 first applies a second preset AC voltage to the edge stabilizing electrode 7 to establish a pre-stabilized electric field in the wafer edge region. Subsequently, the controller 6 applies a first preset AC voltage to the levitation electrode 2, causing the wafer to float. Due to the 90° phase difference between the first and second preset AC voltages, this combination of orthogonal electric fields forms a dynamic gradient electric field in the wafer edge region. When the wafer slightly shifts due to external interference or uneven electric field distribution, this gradient electric field immediately generates a reverse corrective force in the wafer edge region to pull the wafer back to the center position, thereby effectively suppressing wafer shift, vibration, and rotation. This mechanism, in conjunction with the basic levitation force generated by the levitation electrode 2, maintains the stable levitation posture of the wafer, significantly improving levitation accuracy and process stability.

[0055] In some preferred embodiments, the contactless electrostatic levitation support system further includes a spacing adjustment component 8 and a levitation height acquisition component 9. The controller 6 is also used to determine the spacing adjustment amount based on the height deviation when the absolute value of the height deviation between the actual overall levitation height of the wafer to be processed and the preset target levitation height is greater than a first preset threshold, and to determine the AC voltage adjustment amount based on the spacing adjustment amount. Then, the controller controls the spacing adjustment component 8 to adjust the spacing between the edge stabilizing electrode 7 and the levitation electrode 2 based on the spacing adjustment amount, and adjusts the voltage amplitude of the second preset AC voltage based on the AC voltage adjustment amount.

[0056] The spacing adjustment component 8 in this embodiment is a mechanism for precisely adjusting the physical distance between the edge stabilizing electrode 7 and the levitation electrode 2. This component can employ a piezoelectric ceramic actuator, which applies voltage to cause minute deformation, thereby achieving micron-level precise positioning and adjustment of the electrode spacing. The levitation height acquisition component 9 in this embodiment is a device for measuring the actual levitation height between the wafer to be processed and the levitation electrode 2 in real time. This component can employ a laser displacement sensor, which calculates the distance to the wafer surface by emitting a laser beam and receiving the reflected light, thereby obtaining the levitation height. Alternatively, this component can employ a capacitive displacement sensor, which calculates the levitation height by measuring the change in capacitance formed between the wafer and the electrode. The controller 6 in this embodiment is used to determine the spacing adjustment amount based on the height deviation when the absolute value of the height deviation between the actual overall levitation height of the wafer to be processed and the preset target levitation height is greater than a first preset threshold. Since this embodiment only adjusts when there is a significant deviation in the levitation height (the absolute value of the height deviation between the actual overall levitation height of the wafer to be processed and the preset target levitation height is greater than the first preset threshold), this embodiment can avoid excessively frequent or unnecessary adjustments, and determines the adjustment range based on the magnitude of the deviation. Specifically, in this embodiment, the controller 6 can incorporate a PID (Proportional-Integral-Derivative) control algorithm, using the deviation between the actual overall suspension height and the preset target suspension height as input to the algorithm, so that the algorithm outputs a spacing adjustment amount. The controller 6 in this embodiment is also used to determine an AC voltage adjustment amount based on the spacing adjustment amount to compensate for changes in electric field strength caused by variations in electrode spacing, thereby maintaining stable wafer suspension. Specifically, the controller 6 in this embodiment can preset a mapping table, which describes the mapping intervals to which different spacing adjustment amounts belong and the corresponding AC voltage adjustment amounts required to maintain the same suspension effect. The controller 6 is also used to control the spacing adjustment component 8 to adjust the spacing between the edge stabilizing electrode 7 and the suspension electrode 2 based on the spacing adjustment amount. Its function is to directly change the electrode spacing physically to correct the wafer suspension height. The controller 6 sends a control signal (e.g., a voltage signal or a pulse signal) to the spacing adjustment component 8, driving a piezoelectric ceramic driver or stepper motor to perform corresponding displacement, thereby changing the spacing between the edge stabilizing electrode 7 and the suspension electrode 2. The controller 6 is also used to adjust the voltage amplitude of the second preset AC voltage according to the AC voltage adjustment amount. Its function is to further finely adjust the suspension state and stability of the wafer by changing the electric field strength on the edge stabilizing electrode 7. The controller 6 outputs a control voltage through a digital-to-analog converter (DAC), which is applied to the adjustment input terminal of the high voltage power supply, thereby changing the output amplitude of the second preset AC voltage.

[0057] This embodiment effectively solves the wafer levitation height deviation problem by introducing a spacing adjustment component 8 and a levitation height acquisition component 9, combined with the intelligent adjustment function of the controller 6. Specifically, the levitation height acquisition component 9 continuously monitors the actual overall levitation height of the wafer to be processed. When the controller 6 receives the actual overall levitation height data and finds that the absolute value of the height deviation between it and the preset target levitation height exceeds a first preset threshold, it initiates the height adjustment process. The controller 6 first accurately calculates the required spacing adjustment amount based on the detected height deviation to determine the distance and direction that the edge stabilizing electrode 7 needs to move. Then, the controller 6 calculates the corresponding AC voltage adjustment amount based on this spacing adjustment amount, because changes in electrode spacing directly affect the electric field strength, and thus the levitation force; therefore, the voltage needs to be adjusted synchronously to maintain balance. Subsequently, the controller 6 sends a command to the spacing adjustment component 8 to drive it to accurately adjust the spacing between the edge stabilizing electrode 7 and the levitation electrode 2. At the same time, the controller 6 also adjusts the voltage amplitude of the second preset AC voltage applied to the edge stabilizing electrode 7 based on the calculated AC voltage adjustment amount. By employing a dual control strategy that combines physical spacing adjustment with electric field strength adjustment, the system effectively compensates for deviations in wafer levitation height, ensuring that the wafer remains at a stable preset height throughout the entire process, thereby significantly improving process accuracy and reliability. This mechanism, combined with basic electrostatic levitation and edge stabilization functions, forms a closed-loop, adaptive levitation height control system, effectively overcoming the potential levitation height instability issues that may occur with wafers in high-temperature environments.

[0058] In some preferred embodiments, the levitation electrode 2 is divided into multiple levitation regions, and the actual overall levitation height is the average of the actual levitation heights corresponding to all levitation regions. The controller 6 is also used to analyze whether the wafer to be processed is in a horizontal position based on all actual levitation heights. When the controller 6 analyzes that the wafer to be processed is not in a horizontal position, it determines the height abnormal region based on all actual levitation heights, and then controls the levitation electrode 2 to adjust the voltage amplitude of the height abnormal region until the wafer to be processed returns to a horizontal position. The height abnormal region is the levitation region where the absolute value of the difference between the actual levitation height and the actual overall levitation height is greater than a second preset threshold.

[0059] In this embodiment, the levitation electrode 2 is preferably designed as multiple levitation regions. These levitation regions can be physically independent conductive regions, for example, achieved by etching the electrode surface or setting an insulating strip. Each region can be independently voltage-applied. Alternatively, the levitation regions can be logically divided, where the electrode surface is a single unit, but independent voltage drive points are set at different locations to achieve independent control and monitoring of different regions. This partitioned design lays the foundation for fine-grained monitoring and adjustment of the wafer's local height. The actual overall levitation height in this embodiment is obtained by collecting the actual levitation heights corresponding to all levitation regions and calculating the average of these heights. For example, independent displacement sensors can be configured below or above each levitation region to measure the local levitation height of each region in real time. Subsequently, the controller 6 performs an arithmetic average of these local height data to obtain a unified reference value representing the overall levitation state of the wafer. After receiving all the actual levitation height data, the controller 6 can analyze whether the wafer to be processed is in a horizontal orientation. Specifically, the controller 6 can analyze whether the wafer to be processed is in a horizontal position by comparing the height values ​​of different suspended regions. For example, it can calculate the actual deviation between the height of each region and the average height. If all actual deviations are less than or equal to a preset deviation, the wafer to be processed is considered to be in a horizontal position. If there is an actual deviation greater than the preset deviation, the wafer to be processed is considered not to be in a horizontal position. Alternatively, this embodiment can analyze whether the wafer to be processed is in a horizontal position by analyzing whether the actual height difference of the diagonal regions is greater than the preset height difference (this is because when the wafer to be processed is not in a horizontal position, the two suspended regions at the diagonal position will present a state where one suspended region is tilted upward and the other suspended region is drooping down. At this time, the height difference between the two suspended regions at the diagonal position is large (greater than the preset height difference). Therefore, this embodiment can determine whether the wafer to be processed is in a horizontal position by analyzing the actual height difference of the diagonal regions. When the controller 6 analyzes that the wafer to be processed is not in a horizontal orientation, it will determine the height abnormality area based on all actual suspension heights. This step is achieved by comparing the actual suspension height of each suspension area with the average value of all actual suspension heights. Specifically, in this embodiment, the suspension area where the absolute value of the difference between the actual suspension height and the actual overall suspension height is greater than a second preset threshold is regarded as the height abnormality area, thereby accurately locating the area that needs to be locally adjusted.Once a height anomaly region is identified, the controller 6 controls the levitation electrode 2 to adjust the voltage amplitude of these regions until the wafer to be processed returns to a horizontal orientation. For example, the controller 6 can increase or decrease the AC voltage amplitude of the levitation electrode 2 in a region based on the direction and magnitude of the height anomaly. Specifically, if a region is too low in height, the controller 6 will increase the voltage amplitude in that region to enhance the levitation force; conversely, if the height is too high, the voltage amplitude will be decreased. This process can employ a PID control algorithm to adjust the voltage amplitude in real time based on the height deviation and continuously monitor until the wafer orientation stabilizes.

[0060] This embodiment achieves refined management of the wafer's levitation attitude by dividing the levitation electrode 2 into multiple independently monitorable and controllable levitation regions. After the wafer to be processed is electrostatically levied and a fluid isolation layer is formed, the controller 6 continuously uses the levitation height acquisition component 9 to acquire the actual levitation height of each levitation region. The controller 6 first calculates the average value of all these local heights as a benchmark for the overall levitation height of the wafer. Subsequently, the controller 6 determines whether the wafer to be processed is in an ideal horizontal orientation by comparing the difference between each local levitation height and this average value, or by analyzing the distribution of heights in each region. Once a wafer tilt is detected, i.e., it is not in a horizontal orientation, the controller 6 identifies specific height anomaly regions according to preset judgment criteria (e.g., a significant deviation between the actual levitation height and the average value). For these height anomaly regions, the controller 6 precisely adjusts the AC voltage amplitude of the corresponding levitation electrode 2. For example, for regions with excessively low levitation heights, the controller 6 increases the voltage amplitude to enhance the electrostatic levitation force; for regions with excessively high levitation heights, it decreases the voltage amplitude to reduce the electrostatic levitation force. This local voltage regulation process is dynamic and continuous until the height of all suspended regions returns to a level consistent with the average value, thereby ensuring that the wafer under processing maintains a precise horizontal suspension attitude throughout the entire process. This strategy, which combines zone monitoring with local adjustment, effectively compensates for the shortcomings of adjusting only the overall suspension height, ensuring uniform stress and thermal field distribution on the wafer at the microscopic level, and significantly improving process stability and wafer integrity.

[0061] In some preferred embodiments, each suspended region corresponds to at least one air outlet 3, and the real-time temperature distribution information includes the real-time temperature corresponding to each suspended region. The process of adjusting the inert gas flow rate of the air outlet 3 according to the deviation between the real-time temperature distribution information and the preset target temperature includes:

[0062] B1. Determine the temperature anomaly area based on real-time temperature distribution information and preset target temperature; the temperature anomaly area is a floating area where the real-time temperature is different from the preset target temperature.

[0063] B2. Determine the flow adjustment amount corresponding to the temperature anomaly area based on the deviation between the real-time temperature of the temperature anomaly area and the preset target temperature.

[0064] B3. Analyze whether the sum of the inert gas flow rate and the flow rate adjustment amount corresponding to the temperature anomaly area is greater than the upper limit of the preset flow rate range or less than the lower limit of the preset flow rate range. If yes, proceed to step B4 or B5. If no, adjust the inert gas flow rate of the outlet 3 corresponding to the temperature anomaly area according to the flow rate adjustment amount corresponding to the temperature anomaly area. The preset flow rate is within the preset flow rate range.

[0065] B4. When the sum of the inert gas flow rate and flow adjustment amount in the abnormal temperature zone is greater than the upper limit of the preset flow range, analyze whether the inert gas flow rate in the normal temperature zone is less than or equal to the lower limit of the preset flow range. If yes, generate an alarm message. If no, take the difference between the upper limit of the preset flow range and the inert gas flow rate in the abnormal temperature zone as the flow adjustment amount in the abnormal temperature zone, and take the negative of the difference between the sum of the inert gas flow rate and flow adjustment amount in the abnormal temperature zone and the upper limit of the preset flow range as the flow adjustment amount in the normal temperature zone. Then adjust the inert gas flow rate in the abnormal temperature zone according to the flow adjustment amount in the abnormal temperature zone, and adjust the inert gas flow rate in the normal temperature zone according to the flow adjustment amount in the normal temperature zone.

[0066] B5. When the sum of the inert gas flow rate and flow adjustment amount corresponding to the abnormal temperature zone is less than the lower limit of the preset flow range, analyze whether the inert gas flow rate corresponding to the normal temperature zone has reached the upper limit of the preset flow range. If yes, generate an alarm message. If no, take the difference between the lower limit of the preset flow range and the inert gas flow rate corresponding to the abnormal temperature zone as the flow adjustment amount corresponding to the abnormal temperature zone, and take the negative of the difference between the sum of the inert gas flow rate and flow adjustment amount corresponding to the abnormal temperature zone and the lower limit of the preset flow range as the flow adjustment amount corresponding to the normal temperature zone. Then adjust the inert gas flow rate corresponding to the abnormal temperature zone according to the flow adjustment amount corresponding to the abnormal temperature zone, and adjust the inert gas flow rate corresponding to the normal temperature zone according to the flow adjustment amount corresponding to the normal temperature zone.

[0067] Each suspension region in this embodiment is equipped with at least one vent 3 to allow inert gas to be precisely delivered to each suspension region. The real-time temperature distribution information in this embodiment refers to the temperature data of the wafer surface or near-surface acquired by the temperature monitoring component 5 during process execution. This data reflects the real-time temperature state of the wafer in different suspension regions.

[0068] Step B1 aims to identify areas on the wafer to be processed where the temperature deviates from the preset target value. Specifically, the controller 6 receives real-time temperature distribution information from the temperature monitoring component 5 and compares it with the preset target temperature region by region. For any floating region, if there is a difference between its corresponding real-time temperature and the preset target temperature, the region is determined to be a temperature abnormality region.

[0069] In step B2, once an abnormal temperature region is identified, the controller 6 needs to calculate the inert gas flow rate adjustment required to restore the temperature of that region to normal. This adjustment is determined based on the deviation between the real-time temperature and the target temperature. For example, a proportional-integral-derivative (PID) control algorithm can be used, taking the temperature deviation as input to calculate the corresponding flow rate increment or decrement. Alternatively, this embodiment can also determine the inert gas flow rate adjustment based on a preset lookup table (which stores multiple sets of flow rate adjustments corresponding to different temperature deviations).

[0070] In step B3, this step is a safety check mechanism during the flow regulation process. After calculating the flow adjustment amount, the controller 6 first evaluates whether the new flow value, after applying the adjustment amount to the current inert gas flow rate, will exceed the system's preset minimum and maximum flow limits. If the new flow value is still within the allowable range, the controller 6 directly sends a command to the outlet 3 corresponding to the abnormal temperature zone to adjust the inert gas flow rate. If the new flow value exceeds the preset range, the system will activate a more complex compensation or alarm mechanism (step B4 or B5) to prevent flow runaway.

[0071] In step B4, when the inert gas flow rate in a temperature anomaly area needs to be increased, but the sum of the inert gas flow rate corresponding to the temperature anomaly area and the flow rate adjustment amount exceeds the upper limit of the preset flow rate range, this step provides a compensation strategy. The controller 6 checks whether there is still room for downward adjustment of the inert gas flow rate in other normal temperature areas (the inert gas flow rate corresponding to the normal temperature area is less than or equal to the lower limit of the preset flow rate range). If there are normal areas that can be adjusted downwards, the system will adjust the flow rate in the temperature anomaly area to the upper limit of the preset flow rate range, and compensate for the portion exceeding the upper limit by reducing the flow rate in the normal temperature areas. If the flow rate in all normal areas has reached the lower limit of the preset flow rate range, it is considered that the normal temperature areas cannot provide compensation, and the system will generate an alarm message to prompt the operator to intervene.

[0072] In step B5, when the inert gas flow rate in a temperature anomaly zone needs to be reduced, but the sum of the inert gas flow rate corresponding to the temperature anomaly zone and the flow rate adjustment amount is less than the lower limit of the preset flow rate range, this step provides a compensation strategy. Controller 6 checks whether there is still room for upward adjustment of the inert gas flow rate in other normal temperature zones (whether the inert gas flow rate corresponding to the normal temperature zone has reached the upper limit of the preset flow rate range). If there are adjustable normal zones, the system will adjust the flow rate of the anomaly zone to the lower limit of the preset flow rate range, and compensate for the portion below the lower limit by increasing the flow rate of the normal temperature zones. If the flow rate of all normal zones has reached the upper limit of the preset flow rate range, it is considered that the normal temperature zones cannot provide compensation, and the system will generate an alarm message.

[0073] This embodiment not only enables precise local temperature control of the wafer but also effectively avoids system instability or control failure caused by improper flow adjustment by introducing flow range checks and inter-region flow compensation strategies. This refined temperature control, combined with a non-contact electrostatic levitation support system, ensures that the wafer being processed receives a highly uniform temperature field while suspended. This is crucial for maintaining the wafer's horizontal orientation, as uneven temperature can cause wafer warping and affect levitation stability. Simultaneously, the power feedback adjustment module dynamically adjusts the electrode voltage and gas flow rate based on temperature deviations, further enhancing the system's response speed and control accuracy.

[0074] In some preferred embodiments, after the wafer to be processed is placed on the levitation electrode 2, a first preset AC voltage is applied to the levitation electrode 2 to generate an electric field between the wafer to be processed and the levitation electrode 2 and to make the wafer to be processed float. Then, the inert gas supply assembly 4 is controlled to supply a preset flow rate of inert gas to each gas outlet 3 to form a fluid isolation layer between the wafer and the levitation electrode 2.

[0075] A1. Obtain the material thermal conductivity information, thickness information, and surface patterning feature data of the wafer to be processed;

[0076] A2. Input the material thermal conductivity information, thickness information and surface patterning feature data into the pre-trained wafer thermal model so that the wafer thermal model outputs the predicted wafer temperature gradient information;

[0077] A3. Based on the predicted wafer temperature gradient information, extract the corresponding AC voltage as the first preset AC voltage from the pre-constructed mapping table of wafer temperature gradient and its corresponding AC voltage and gas flow rate combination, and extract the corresponding gas flow rate as the preset flow rate.

[0078] A4. After the wafer to be processed is placed on the levitation electrode 2, a first preset AC voltage is applied to the levitation electrode 2 to generate an electric field between the wafer to be processed and the levitation electrode 2 and to make the wafer to be processed float. Then, the inert gas supply component 4 is controlled to supply a preset flow rate of inert gas to each gas outlet 3 to form a fluid isolation layer between the wafer and the levitation electrode 2.

[0079] The material thermal conductivity information in this embodiment refers to the ability of the wafer material to conduct heat. This information is a key physical parameter affecting the temperature distribution of the wafer in high-temperature environments. This information can be obtained by consulting datasheets provided by wafer material suppliers, through experimental measurements (e.g., transient planar heat source method or laser scintillation method), or by retrieving it from a pre-defined material database. The thickness information in this embodiment refers to the geometric thickness of the wafer to be processed. This information directly affects the wafer's heat capacity and heat conduction path, thereby affecting the temperature response speed and uniformity of the wafer during heating. This information can be obtained through optical measurement equipment (such as laser thickness gauges), mechanical contact measurement equipment, or read from the wafer's production specification documents. The surface patterning feature data in this embodiment refers to the microstructures or circuit patterns present on the wafer surface. These patterns alter the emissivity, absorptivity, and local heat capacity of the wafer surface, thereby affecting thermal radiation and convection, leading to local temperature differences. This data can be obtained through wafer design documents (such as GDSII files), optical microscope image analysis, or scanning electron microscope (SEM) image processing. The pre-trained wafer thermal model in this embodiment is a computational model capable of simulating the temperature distribution of a wafer under specific process conditions. This model can be constructed using machine learning algorithms (such as neural networks and support vector machines), and outputs a predicted temperature distribution by inputting the wafer's material, thickness, patterning features, and process parameters. The predicted wafer temperature gradient information in this embodiment refers to the potential temperature non-uniformity distribution on the surface or inside the wafer during the upcoming process. This information can be output in the form of temperature distribution maps, temperature gradient vector fields, or temperature difference values ​​in key areas, guiding subsequent parameter adjustments to achieve a more uniform temperature field. The pre-built mapping table in this embodiment is a database storing the correspondence between different wafer temperature gradient information ranges and the optimal combination of AC voltage and gas flow rate required to achieve those temperature gradient ranges. This mapping table can be pre-generated and filled through extensive experimental testing or numerical simulations to ensure that each predicted temperature gradient can find a set of optimal initial control parameters. This embodiment introduces a feedforward compensation algorithm to perform in-depth analysis and prediction of the wafer's inherent thermal characteristics before the wafer begins to levitate and form an isolation layer, thereby achieving precise pre-setting of initial levitation and gas supply parameters. Specifically, controller 6 first acquires information on the thermal conductivity, thickness, and surface patterning characteristics of the wafer to be processed. These data are intrinsic properties of the wafer's thermal behavior and directly affect its thermal response in high-temperature environments. Subsequently, this detailed wafer characteristic data is input into a pre-trained wafer thermal model. This thermal model, trained with a large amount of experimental or simulation data, can accurately simulate the temperature distribution of different wafers under specific process conditions and output predicted wafer temperature gradient information. This prediction information reveals the thermal field inhomogeneity that may occur in the wafer in the initial stage.Based on these predicted wafer temperature gradients, controller 6 queries a pre-built mapping table that stores the correspondence between various wafer temperature gradients and the optimal combination of AC voltage and gas flow rate required to achieve these gradients. Through this query, the system can extract a first preset AC voltage and preset flow rate tailored to the characteristics of the wafer to be processed. These preset parameters take into account the effects of wafer material, thickness, and surface patterning on differences in thermal resistance and thermal radiation characteristics, aiming to preemptively offset potential thermal field inhomogeneities. Finally, after the wafer to be processed is placed on the levitation electrode 2, controller 6 immediately applies the first preset AC voltage extracted from the mapping table, causing the wafer to rapidly float under the influence of the electric field. Subsequently, controller 6 controls the inert gas supply assembly 4 to supply inert gas to each outlet 3 on the levitation electrode 2 according to the extracted preset flow rate, thereby forming a uniform or compensated fluid isolation layer between the wafer and the levitation electrode 2. The entire process forms a feedforward control loop based on wafer characteristics, pre-compensating for potential thermal non-uniformities before the process begins, ensuring that the wafer reaches an optimized thermal state during the initial levitation and isolation layer formation stages. Compared with traditional methods that rely solely on real-time feedback adjustment, this approach can more proactively and precisely control the initial thermal environment of the wafer, significantly reducing the risk of thermal stress damage caused by initial thermal shock or non-uniformities during high-temperature processing.

[0080] In some preferred embodiments, the contactless electrostatic levitation support system further includes a temperature compensation electrode 10, which is disposed below the levitation electrode 2. The temperature compensation electrode 10 is used to compensate the temperature of the wafer to be processed. In this embodiment, the temperature compensation electrode 10 is an electrode used to actively regulate the temperature of the wafer to be processed. This compensation function can be achieved by the controller 6 adjusting the heating or cooling power of the temperature compensation electrode 10 based on the real-time temperature distribution information obtained by the temperature monitoring component 5. Preferably, the temperature compensation electrode 10 in this embodiment can be divided into multiple independently controlled areas to achieve precise compensation of the local temperature of the wafer to be processed. This embodiment expands the system's temperature control mechanism by introducing the temperature compensation electrode 10 into the contactless electrostatic levitation support system and placing it below the levitation electrode 2. During the process, when the controller 6 uses the temperature monitoring component 5 to acquire real-time temperature distribution information of the wafer to be processed, and adjusts the inert gas flow rate of the outlet 3 for preliminary temperature control based on the deviation between this information and the preset target temperature, if the wafer to be processed still has local temperature unevenness, such as due to uneven heat conduction or local deviation caused by the influence of the external thermal environment, the controller 6 can activate or adjust the temperature compensation electrode 10. This allows the temperature compensation electrode 10 to directly compensate for the temperature of the local area of ​​the wafer to be processed, which is in a suspended state, through active heating or cooling. This dual control strategy, combining macroscopic temperature control by adjusting the inert gas flow rate with microscopic fine adjustment of the temperature compensation electrode 10, enables the system to manage the temperature field of the wafer to be processed more comprehensively and accurately. In this way, the solution of this application can effectively compensate for the problem of wafer temperature unevenness and ensure that the wafer to be processed maintains a highly uniform temperature distribution throughout the entire process.

[0081] In some preferred embodiments, the non-contact electrostatic levitation support system further includes a preheating unit 11, which is disposed between the inert gas supply component 4 and the outlet 3. The preheating unit 11 is used to heat the inert gas supplied by the inert gas supply component 4 to a preset temperature, which is lower than a preset target temperature. In this embodiment, the preheating unit 11 is a device for raising the temperature of the inert gas, and it can be implemented in various forms. For example, the preheating unit 11 can be a cavity with a built-in electric heating wire or ceramic heating rod, through which the inert gas is heated; or it can be a heat exchanger that uses an external heat source (such as circulating hot oil or steam) to heat the inert gas through heat conduction. The core function of the preheating unit 11 in this embodiment is to preheat the inert gas entering the process chamber 1 to prevent the wafer to be processed from failing to reach the required process temperature due to the inert gas temperature being too low. Specifically, the preheating unit 11 in this embodiment is used to heat the inert gas supplied by the inert gas supply component 4 to a preset temperature, which is set to be lower than the preset target temperature. This ensures that sufficient heat is provided to prevent local cooling of the wafer while preventing the inert gas itself from becoming a new heat source, causing excessive interference with the overall preset target temperature of the wafer or leading to local overheating. This temperature setting strategy aims to achieve precise temperature control, ensuring that the fluid isolation layer, while maintaining wafer suspension, can help maintain the temperature uniformity of the wafer, rather than actively heating the wafer to be processed to the preset target temperature.

[0082] In some preferred embodiments, the preset temperature is 200-400°C. This embodiment ensures that the temperature difference between the inert gas and the wafer being processed is within a controllable and suitable range when the inert gas forms the fluid isolation layer by limiting the preset temperature of the inert gas to 200-400°C. This embodiment effectively avoids localized cold shock to the wafer caused by excessively low inert gas temperature, thereby significantly reducing the risk of thermal stress damage to the wafer during high-temperature processes. At the same time, this temperature range also avoids excessively high inert gas temperature, thus maintaining the stability and uniformity of the overall thermal field of the wafer and optimizing heat transfer efficiency. Therefore, this embodiment effectively improves the temperature control accuracy and stability of the wafer in the non-contact electrostatic levitation support system, thereby improving process repeatability and yield.

[0083] As can be seen from the above, the contactless electrostatic levitation support system provided in this application fundamentally eliminates the physical contact between the wafer and the support through contactless levitation technology, effectively avoiding metal ion contamination, particulate contamination and thermal stress damage caused by traditional support methods.

[0084] Secondly, such as Figure 4As shown, this application also provides a contactless electrostatic levitation support method, which is applied to the contactless electrostatic levitation support system provided in the first aspect above. The method includes the following steps:

[0085] S1. After the wafer to be processed is placed on the levitation electrode 2, a first preset AC voltage is applied to the levitation electrode 2 to generate an electric field between the wafer to be processed and the levitation electrode 2 and to make the wafer to be processed float. Then, the inert gas supply component 4 is controlled to supply a preset flow rate of inert gas to each gas outlet 3 to form a fluid isolation layer between the wafer and the levitation electrode 2. The frequency of the first preset AC voltage is 1-10kHz.

[0086] S2. During the process, the temperature monitoring component 5 is used to obtain the real-time temperature distribution information of the wafer to be processed, and the inert gas flow rate of the outlet 3 is adjusted according to the deviation between the real-time temperature distribution information and the preset target temperature.

[0087] The contactless electrostatic levitation support method provided in this application is applied to the contactless electrostatic levitation support system provided in the first aspect above. The principle of the contactless electrostatic levitation support method provided in this embodiment is the same as the principle of the contactless electrostatic levitation support system provided in the first aspect above, and will not be repeated here.

[0088] As can be seen from the above, the contactless electrostatic levitation support system and method provided in this application fundamentally eliminates the physical contact between the wafer and the support through contactless levitation technology. Therefore, this application can effectively avoid metal ion contamination, particulate contamination and thermal stress damage caused by traditional support methods.

[0089] In the embodiments provided in this application, it should be understood that relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0090] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A contactless electrostatic levitation support system, characterized in that, The contactless electrostatic levitation support system includes: Process chambers; A suspended electrode is disposed within the process chamber; Multiple air outlets are arranged in a circular array on the suspended electrode; An inert gas supply assembly is connected to all of the aforementioned gas outlets; Temperature monitoring components; The controller is configured to apply a first preset AC voltage to the levitation electrode after the wafer to be processed is placed on the levitation electrode, so as to generate an electric field between the wafer to be processed and the levitation electrode to make the wafer to be processed float. Then, it controls the inert gas supply component to supply a preset flow rate of inert gas to each of the gas outlets to form a fluid isolation layer between the wafer and the levitation electrode. It is also configured to use the temperature monitoring component to obtain real-time temperature distribution information of the wafer to be processed during the process execution, and adjust the inert gas flow rate of the gas outlets according to the deviation between the real-time temperature distribution information and the preset target temperature. The frequency of the first preset AC voltage is 1-10kHz.

2. The contactless electrostatic levitation support system according to claim 1, characterized in that, The contactless electrostatic levitation support system further includes an edge stabilizing electrode, which is sleeved outside the levitation electrode and the distance between the edge stabilizing electrode and the levitation electrode is greater than 0. The controller is also used to apply a second preset AC voltage to the edge stabilizing electrode before applying a first preset AC voltage to the levitation electrode, wherein the phase difference between the first preset AC voltage and the second preset AC voltage is 90°.

3. The contactless electrostatic levitation support system according to claim 2, characterized in that, The contactless electrostatic levitation support system further includes a spacing adjustment component and a levitation height acquisition component. The controller is also used to determine a spacing adjustment amount based on the height deviation when the absolute value of the height deviation between the actual overall levitation height of the wafer to be processed and the preset target levitation height is greater than a first preset threshold, and to determine an AC voltage adjustment amount based on the spacing adjustment amount. Then, the controller controls the spacing adjustment component to adjust the spacing between the edge stabilizing electrode and the levitation electrode based on the spacing adjustment amount, and adjusts the voltage amplitude of the second preset AC voltage based on the AC voltage adjustment amount.

4. The contactless electrostatic levitation support system according to claim 3, characterized in that, The levitation electrode is divided into multiple levitation regions, and the actual overall levitation height is the average of the actual levitation heights corresponding to all the levitation regions. The controller is also used to analyze whether the wafer to be processed is in a horizontal position based on all the actual levitation heights. When the analysis indicates that the wafer to be processed is not in a horizontal position, the controller is also used to determine a height abnormality region based on all the actual levitation heights, and then control the levitation electrode to adjust the voltage amplitude of the height abnormality region until the wafer to be processed returns to a horizontal position. The height abnormality region is a levitation region where the absolute value of the difference between the actual levitation height and the actual overall levitation height is greater than a second preset threshold.

5. The contactless electrostatic levitation support system according to claim 4, characterized in that, Each of the suspended regions corresponds to at least one of the air outlets, and the real-time temperature distribution information includes the real-time temperature corresponding to each of the suspended regions. The process of adjusting the inert gas flow rate of the air outlets based on the deviation between the real-time temperature distribution information and the preset target temperature includes: B1. Determine the temperature anomaly region based on the real-time temperature distribution information and the preset target temperature; the temperature anomaly region is a floating region where the corresponding real-time temperature is not equal to the preset target temperature; B2. Determine the flow rate adjustment amount corresponding to the temperature anomaly area based on the deviation between the real-time temperature corresponding to the temperature anomaly area and the preset target temperature. B3. Analyze whether the sum of the inert gas flow rate corresponding to the abnormal temperature region and the flow rate adjustment amount is greater than the upper limit of the preset flow rate range or less than the lower limit of the preset flow rate range. If yes, proceed to step B4 or B5. If no, adjust the inert gas flow rate of the outlet corresponding to the abnormal temperature region according to the flow rate adjustment amount corresponding to the abnormal temperature region. The preset flow rate is within the preset flow rate range. B4. When the sum of the inert gas flow rate and the flow rate adjustment amount corresponding to the abnormal temperature zone is greater than the upper limit of the preset flow range, analyze whether the inert gas flow rate corresponding to the normal temperature zone is less than or equal to the lower limit of the preset flow range. If yes, generate an alarm message. If no, take the difference between the upper limit of the preset flow range and the inert gas flow rate corresponding to the abnormal temperature zone as the flow rate adjustment amount corresponding to the abnormal temperature zone, and take the negative of the difference between the sum of the inert gas flow rate and the flow rate adjustment amount corresponding to the abnormal temperature zone and the upper limit of the preset flow range as the flow rate adjustment amount corresponding to the normal temperature zone. Then, adjust the inert gas flow rate corresponding to the abnormal temperature zone according to the flow rate adjustment amount corresponding to the abnormal temperature zone, and adjust the inert gas flow rate corresponding to the normal temperature zone according to the flow rate adjustment amount corresponding to the normal temperature zone. B5. When the sum of the inert gas flow rate and the flow rate adjustment amount corresponding to the abnormal temperature region is less than the lower limit of the preset flow range, analyze whether the inert gas flow rate corresponding to the normal temperature region has reached the upper limit of the preset flow range. If yes, generate an alarm message. If no, take the difference between the lower limit of the preset flow range and the inert gas flow rate corresponding to the abnormal temperature region as the flow rate adjustment amount corresponding to the abnormal temperature region, and take the negative of the difference between the sum of the inert gas flow rate and the flow rate adjustment amount corresponding to the abnormal temperature region and the lower limit of the preset flow range as the flow rate adjustment amount corresponding to the normal temperature region. Then, adjust the inert gas flow rate corresponding to the abnormal temperature region according to the flow rate adjustment amount corresponding to the abnormal temperature region, and adjust the inert gas flow rate corresponding to the normal temperature region according to the flow rate adjustment amount corresponding to the normal temperature region.

6. The contactless electrostatic levitation support system according to claim 1, characterized in that, The process of applying a first preset AC voltage to the floating electrode after the wafer to be processed is placed on the floating electrode to generate an electric field between the wafer to be processed and the floating electrode and to make the wafer to be processed float, and then controlling the inert gas supply assembly to supply a preset flow rate of inert gas to each of the gas outlets to form a fluid isolation layer between the wafer and the floating electrode includes: A1. Obtain the material thermal conductivity information, thickness information, and surface patterning feature data of the wafer to be processed; A2. Input the material thermal conductivity information, the thickness information, and the surface patterning feature data into a pre-trained wafer thermal model so that the wafer thermal model outputs predicted wafer temperature gradient information; A3. Based on the predicted wafer temperature gradient information, extract the corresponding AC voltage as the first preset AC voltage from the pre-constructed mapping table of wafer temperature gradient and its corresponding AC voltage and gas flow rate combination, and extract the corresponding gas flow rate as the preset flow rate. A4. After the wafer to be processed is placed on the levitation electrode, a first preset AC voltage is applied to the levitation electrode to generate an electric field between the wafer to be processed and the levitation electrode and to make the wafer to be processed float. Then, the inert gas supply assembly is controlled to supply a preset flow rate of inert gas to each of the gas outlets to form a fluid isolation layer between the wafer and the levitation electrode.

7. The contactless electrostatic levitation support system according to claim 1, characterized in that, The contactless electrostatic levitation support system also includes a temperature compensation electrode, which is disposed below the levitation electrode and is used to compensate the temperature of the wafer to be processed.

8. The contactless electrostatic levitation support system according to claim 1, characterized in that, The non-contact electrostatic levitation support system also includes a preheating unit, which is disposed between the inert gas supply component and the gas outlet. The preheating unit is used to heat the inert gas supplied by the inert gas supply component to a preset temperature, which is lower than a preset target temperature.

9. The contactless electrostatic levitation support system according to claim 8, characterized in that, The preset temperature is 200-400℃.

10. A non-contact electrostatic levitation support method, characterized in that, The contactless electrostatic levitation support method is applied in the contactless electrostatic levitation support system as described in any one of claims 1-9, and the contactless electrostatic levitation support method includes the following steps: S1. After the wafer to be processed is placed on the levitation electrode, a first preset AC voltage is applied to the levitation electrode to generate an electric field between the wafer to be processed and the levitation electrode and to make the wafer to be processed float. Then, the inert gas supply component is controlled to supply a preset flow rate of inert gas to each of the gas outlets to form a fluid isolation layer between the wafer and the levitation electrode. The frequency of the first preset AC voltage is 1-10kHz. S2. During the process execution, the temperature monitoring component is used to obtain the real-time temperature distribution information of the wafer to be processed, and the inert gas flow rate of the outlet is adjusted according to the deviation between the real-time temperature distribution information and the preset target temperature.

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