A control method and power supply applied to an electrostatic chuck of an etching machine

Abstract

The application provides a control method and power supply applied to an electrostatic chuck of an etching machine. According to rated specification data of a wafer, wafer charge detection demonstration operation is performed to estimate a threshold value of negative charge of the wafer. Based on the threshold value, actual negative charge content value of the wafer is detected, adsorption force data generated by the negative charge of the wafer is obtained through charge amount analysis calculation. According to the adsorption force data, adsorption force control parameters are extracted, the positive charge content value of the electrostatic chuck is regulated based on the adsorption force control parameters, and a regulation result is obtained. According to the regulation result, the positive charge amount of the electrostatic chuck and the negative charge amount of the wafer are matched in equal amount, and the wafer is controlled to be operated by the electrostatic chuck to perform etching work. The application can control the electrostatic chuck to adsorb the wafer, thereby completing accurate etching work, and the close adsorption between the electrostatic chuck and the wafer due to the matched positive and negative charges can ensure the safety of the etching equipment and the operator.

Description

Technical Field

[0001] This invention relates to the field of control technology, and in particular to a control method and power supply for an electrostatic chuck used in an etching machine. Background Technology

[0002] At present, in the existing technology, when electrostatic chucks adsorb and grab objects, they only limit and eliminate the friction between the electrostatic chuck and the object being grabbed, so as to ensure that the electrostatic chuck can achieve the maximum adsorption effect while eliminating the influence of friction. This technology has the problem of inaccurate adsorption of objects by electrostatic chucks. For example, in the invention CN201510277990-A method for controlling the suction force of electrostatic chucks and [1] Morita Y, Okumura N, Nakanishi T. Electrostatic chuck and the method of operating the same[J].US,1998., there is a method of fitting the deformation of the wafer and then calculating to control the electrostatic chuck to perform adsorption operation. However, the fitting method will introduce errors, and there may be inaccurate adsorption force calculation. Therefore, in this invention, the positive and negative charge content values ​​of the electrostatic chuck and the wafer are adjusted to match, and the influence of temperature on the adsorption force is eliminated. By controlling the electrostatic chuck to operate the wafer for etching, the adsorption force of the electrostatic chuck can be controlled more accurately, and the safety of the adsorption equipment and operators can be guaranteed. Summary of the Invention

[0003] This invention provides a control method and power supply for an electrostatic chuck used in an etching machine, in order to solve the problems mentioned in the background art.

[0004] This invention provides a control method for an electrostatic chuck used in an etching machine, comprising:

[0005] Based on the wafer's rated specifications, a wafer charge detection demonstration was conducted to estimate the threshold for the wafer to carry negative charge.

[0006] Based on the threshold, the actual negative charge content of the wafer is detected, and the adsorption force data generated by the negative charge of the wafer is obtained through charge analysis and calculation.

[0007] Based on the adsorption force data, adsorption force control parameters are extracted, and the positive charge content of the electrostatic chuck is adjusted based on the adsorption force control parameters to obtain the adjustment result;

[0008] Based on the control results, the positive charge of the electrostatic chuck is matched equally with the negative charge of the wafer, and the electrostatic chuck is controlled to operate the wafer for etching.

[0009] As one embodiment of this technical solution, the step of performing a wafer charge detection demonstration operation based on the wafer's rated specification data to estimate the threshold for the wafer to bear negative charge includes:

[0010] Based on the wafer's rated specifications, obtain the wafer's conductivity parameters.

[0011] Based on the conductivity parameter data, the energizing voltage and current are limited to obtain the electric field strength value of the wafer.

[0012] An electrostatic force is generated based on the electric field strength value, and the negative charge generated by the electrostatic force is detected.

[0013] By calculating the negative charge content of the wafer, the electrostatic adsorption force of the wafer within a reasonable range is determined, and the electrostatic adsorption data of the wafer is obtained.

[0014] Based on the wafer electrostatic adsorption data, conditions are imposed, and the negative charge carrying threshold of the wafer is estimated through these conditions.

[0015] As one embodiment of this technical solution, the conditional limitation on the electrostatic adsorption force threshold includes:

[0016] Based on the obtained wafer electric field strength, the electrostatic force threshold of the wafer is estimated, and the estimation result is obtained.

[0017] Based on the estimated results, conditional restrictions are imposed on the electrostatic force threshold of the wafer;

[0018] Based on the aforementioned constraints, the negative charge content generated by electrostatic force on the wafer is detected. When the negative charge content exceeds the preset maximum wafer load capacity, the wafer is powered off, and the processing result is obtained.

[0019] Based on the processing results, the electrostatic force of the wafer is regulated to adjust the negative charge content of the wafer within the estimated threshold range.

[0020] Based on the aforementioned constraints, when the negative charge content of the detected wafer is lower than the preset minimum wafer load capacity, the wafer is powered off, and the processing result is obtained.

[0021] Based on the processing results, the electrostatic force of the wafer is regulated to adjust the negative charge content of the wafer within the estimated threshold range.

[0022] As one embodiment of this technical solution, based on the threshold, the actual negative charge content of the wafer is detected, and the adsorption force data generated by the negative charge on the wafer is obtained through charge analysis and calculation, including:

[0023] Based on the obtained wafer negative charge threshold, an electrostatic induction experiment was conducted on the wafer to obtain the electrostatic induction parameters of the wafer after energization.

[0024] The negative charge content of the wafer at different time periods is detected in real time using the electrostatic induction parameters, and the negative charge content is analyzed and calculated to obtain the calculation results.

[0025] Based on the calculation results, charge data values ​​are extracted, and electrostatic Coulomb force data values ​​generated by negative charge on the wafer are obtained according to the charge data values.

[0026] Based on the electrostatic Coulomb force data, the adsorption force data generated by the negative charge on the wafer is obtained by performing data calculation through the resultant force equation.

[0027] As one embodiment of this technical solution, the real-time detection of the negative charge content of the wafer at different time periods, and the analysis and calculation of the negative charge content to obtain the calculation results, includes:

[0028] The content of negative charge in the wafer was detected at different time periods after it was powered on, and the corresponding data value of time-negative charge content was obtained;

[0029] Based on the data values ​​of the charge adsorbed on the wafer during a fixed time period and the corresponding time period, a curve of charge change over time is generated.

[0030] The negative charge of the wafer is verified over time using the curve, the charge change parameters are obtained, and the charge change parameters are stored to obtain the stored data.

[0031] Based on the stored data, the wafer negative charge content value is analyzed and calculated to obtain the calculation results;

[0032] Based on the results, data on the electrostatic force generated by the negative charge on the wafer are obtained.

[0033] As one embodiment of this technical solution, the positive charge content of the electrostatic chuck is adjusted based on the adsorption force control parameter to obtain the adjustment result, including:

[0034] Based on the adsorption force data generated by the negative charge on the wafer, the adsorption force control parameters are extracted;

[0035] Based on the aforementioned adsorption force control parameters, the positive charge of the electrostatic chuck is adjusted to obtain the processing result;

[0036] Based on the processing results, determine whether the positive charge control method of the electrostatic chuck is reasonable, and obtain the judgment result;

[0037] If the judgment result is unreasonable, the power supply to the electrostatic chuck will be cut off and an alarm will be displayed.

[0038] When the judgment result is reasonable, the electrostatic chuck control parameters are extracted and the electrostatic chuck control parameters are stored.

[0039] Based on the stored data, the electrostatic force generated by the positive charge of the electrostatic chuck is calculated and analyzed to obtain the corresponding adsorption force value of the electrostatic chuck.

[0040] As one embodiment of this technical solution, the alarm display includes:

[0041] The alarm display is divided into three categories: abnormal control alarm, abnormal temperature alarm, and leakage current alarm.

[0042] When an abnormal control alarm occurs, a voice alarm prompt for abnormal control is issued, and an alarm record is generated and stored in the database.

[0043] When a temperature abnormality alarm occurs, a temperature abnormality LED flashing alarm is activated, and an alarm record is generated and stored in the database.

[0044] When a leakage current alarm occurs, alternating voice and flashing light alarms are provided, and an alarm record is generated and stored in the database.

[0045] As one embodiment of this technical solution, based on the control result, the positive charge of the electrostatic chuck is matched equally with the negative charge of the wafer, and the electrostatic chuck is controlled to operate the wafer for etching operations, including:

[0046] Based on the acquisition of electrostatic chuck adsorption force and wafer adsorption force, control rules for electrostatic chuck and wafer adsorption force are formulated.

[0047] According to the control rules, the temperature during the adsorption of the electrostatic chuck and the wafer is detected, and the temperature detection results are obtained.

[0048] Based on the temperature detection results, the electrostatic chuck and wafer are adjusted to eliminate the influence of temperature error on the adhesion force of the electrostatic chuck and wafer.

[0049] By eliminating temperature errors, the positive charge of the electrostatic chuck is matched equally with the negative charge of the wafer to obtain accurate adhesion between the electrostatic chuck and the wafer.

[0050] Based on the adsorption force, the electrostatic chuck is controlled to operate the wafer for etching operations.

[0051] As one embodiment of this technical solution, obtaining the temperature detection result includes:

[0052] When the detection result shows a normal state, the detected temperature data is stored, and a temperature change curve is generated based on the temperature data;

[0053] When the detection result shows an abnormal state, a temperature abnormality alarm will be issued;

[0054] Based on the aforementioned temperature anomaly alarm, temperature anomaly analysis is performed, and temperature anomaly solutions are formulated.

[0055] Based on the aforementioned temperature anomaly solution, the electrostatic chuck and wafer were subjected to cooling and insulation treatment, and the treatment results were obtained.

[0056] Based on the processing results, feedback is provided, and the feedback results are obtained.

[0057] As one embodiment of this technical solution, the power supply comprises a regulated power supply and a frequency converter; wherein,

[0058] The regulated power supply is used to supply voltage to the electrostatic chuck and to compensate for voltage fluctuations.

[0059] The frequency converter is used to adjust the voltage frequency in the circuit. According to the voltage requirements when the electrostatic chuck is adsorbed by the wafer, the frequency converter is used to regulate the circuit voltage.

[0060] Based on the aforementioned control process, the voltage required for etching the wafer by the electrostatic chuck is obtained;

[0061] The regulated power supply and the frequency converter are combined and packaged to generate a power supply for the electrostatic chuck.

[0062] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0063] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0064] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0065] Figure 1 This is a flowchart illustrating a control method and power supply for an electrostatic chuck used in an etching machine, as described in an embodiment of the present invention.

[0066] Figure 2 This is an example of a control method for an electrostatic chuck used in an etching machine and an external view of the electrostatic chuck in a power supply.

[0067] Figure 3 This is a flowchart illustrating a control method and power supply alarm for an electrostatic chuck used in an etching machine, as described in an embodiment of the present invention. Detailed Implementation

[0068] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0069] exist Figure 1 The process involves detecting the negative charge on the wafer and then calculating the adhesion force of the negative charge on the wafer. Based on the above technical data, the electrostatic chuck is also calculated to match the positive charge content on the electrostatic chuck with the negative charge content on the wafer, which allows for more precise control of the electrostatic chuck to operate the wafer for etching. Figure 2 This is an image of the electrostatic chuck's appearance. Figure 2 The appearance model of the electrostatic chuck can be clearly and intuitively seen, which can provide an example for subsequent calculation operations; Figure 3 This is an alarm flowchart. The alarm function is something not covered in existing technology. Figure 3 The process operation can promptly issue alarm prompts if any abnormalities occur during the etching process of the wafer operated by the electrostatic chuck.

[0070] Example 1:

[0071] according to Figure 1 As shown, this embodiment of the invention provides a control method for an electrostatic chuck used in an etching machine, comprising:

[0072] Based on the wafer's rated specifications, a wafer charge detection demonstration was conducted to estimate the threshold for the wafer to carry negative charge.

[0073] Based on the threshold, the actual negative charge content of the wafer is detected, and the adsorption force data generated by the negative charge of the wafer is obtained through charge analysis and calculation.

[0074] Based on the adsorption force data, adsorption force control parameters are extracted, and the positive charge content of the electrostatic chuck is adjusted based on the adsorption force control parameters to obtain the adjustment result;

[0075] Based on the control results, the positive charge of the electrostatic chuck is matched equally with the negative charge of the wafer, and the electrostatic chuck is controlled to operate the wafer for etching.

[0076] The working principle of the above technical solution is as follows: In existing technologies, such as when an electrostatic chuck adsorbs and grasps an object, it only limits and eliminates the frictional force that may exist between the electrostatic chuck and the object being grasped, thereby ensuring that the electrostatic chuck achieves the maximum adsorption effect while eliminating the influence of friction. However, this technology mainly calculates the change in charge during the mutual adsorption process between the electrostatic chuck and the wafer, thereby generating a changing electric field, and then generating electrostatic force. It controls the positive charge content of the electrostatic chuck and the negative charge content of the wafer to match, and then the two are adsorbed and connected. Based on the adsorption force generated by the adsorption, the electrostatic chuck is controlled to operate the wafer to perform an etching action. This ensures the accurate completion of the adsorption and grasping task and will not cause equipment damage.

[0077] The beneficial effects of the above technical solution are as follows: after the wafer is electrically connected, the negative charge content threshold of the wafer is detected, and then calculations can be performed based on these threshold data to facilitate the understanding of the wafer's adsorption capacity. These data have a reference value for adjusting the positive charge content of the electrostatic chuck, thereby making it easier to master the operation method of the electrostatic chuck.

[0078] Example 2:

[0079] In one specific embodiment, the step of performing a wafer charge detection demonstration operation based on the wafer's rated specification data to estimate the threshold for the wafer to bear negative charge includes:

[0080] Based on the wafer's rated specifications, obtain the wafer's conductivity parameters.

[0081] Based on the conductivity parameter data, the energizing voltage and current are limited to obtain the electric field strength value of the wafer.

[0082] An electrostatic force is generated based on the electric field strength value, and the negative charge generated by the electrostatic force is detected.

[0083] By calculating the negative charge content of the wafer, the electrostatic adsorption force of the wafer within a reasonable range is determined, and the electrostatic adsorption data of the wafer is obtained.

[0084] Based on the wafer electrostatic adsorption data, conditions are imposed, and the negative charge carrying threshold of the wafer is estimated through these conditions.

[0085] The working principle of the above technical solution is as follows: In the prior art, an initial suction force is set on the wafer before the wafer process. Then, under the action of the suction force, the wafer is attracted by the electrostatic chuck. During the wafer process, the change in wafer curvature is fitted as a function of the process time. Then, calculations are performed based on the obtained function to ensure that the wafer is just attracted by the electrostatic chuck during the process. This technology is too cumbersome, and the fitting of the wafer curvature is not very accurate. However, the above technology of the present invention obtains the conductivity parameters of the wafer, limits the current and voltage based on the parameters, detects the negative charge generated by the wafer, calculates the detected charge value, estimates the negative charge carrying capacity of the wafer, and determines the approximate range of the attraction force of the electrostatic chuck. For example, the charge data value of the wafer is calculated. These data values ​​can be used to limit the attraction force of the wafer. First, the attraction force value on the wafer is calculated, and then the attraction force is optimized to obtain a more accurate attraction force value. Conditions are then imposed on the optimized attraction force value, and the negative charge carrying threshold of the wafer is estimated.

[0086] The beneficial effects of the above technical solution are as follows: based on the obtained conductivity parameters of the wafer, and then by detecting the change in electric field caused by the change in charge after energization, the adsorption force data of the wafer can be obtained by calculation. The calculation of the adsorption force data can provide a data basis for the subsequent control of the adsorption force of the electrostatic chuck.

[0087] Example 3:

[0088] In one specific embodiment of the present invention, by adapting and adsorbing the negative and positive charges of the wafer and the electrostatic chuck, it is necessary to detect the charge and calculate control and adjustment parameters. Then, based on the parameters and stored data, calculations are performed to first calculate the wafer's adsorption force value, and then to estimate the negative charge value that the wafer can bear based on the wafer's adsorption force value. Finally, the charge of the electrostatic chuck is adjusted according to the estimated wafer negative charge carrying threshold. Let the adsorption force be f(x).

[0089]

[0090] Where k is the electrostatic constant; q1 is point charge 1; q2 is point charge 2; r is the distance between q1 and q2; f x Let xE(i) be the net force on the wafer caused by the charges; xE(i) is the electric field strength generated by the i-th charge among the n charges. This represents the superposition of the electric fields received by the i-th charge;

[0091] Then, the adsorption force is optimized through calculation:

[0092]

[0093] x represents the value of different component forces; b represents the value of the maximum component force; a represents the value of the minimum component force; This means that integrating the components of the resultant force can optimize the value of the resultant force;

[0094] By superimposing the electric field strengths experienced by the charge, the actual electric field influence on the charge on the wafer can be obtained. Then, the adsorption force on the wafer can be calculated, and the optimal value of the adsorption force can be constrained.

[0095]

[0096] f min估 Indicates the estimated minimum adsorption force; f max估 This represents the estimated maximum adsorption force. By limiting the adsorption force, the etching work on the wafer can be completed within a reasonable and safe adsorption threshold. Based on the above formula for limiting the adsorption force, the negative charge carrying threshold of the wafer can be estimated. Through the above technical solution, the estimated negative charge carrying value of the wafer can serve as the data basis for adjusting the positive charge of the electrostatic chuck to match it.

[0097] Example 4:

[0098] In one specific embodiment, the conditional limitation on the electrostatic adsorption force threshold includes:

[0099] Based on the obtained wafer electric field strength, the electrostatic force threshold of the wafer is estimated, and the estimation result is obtained.

[0100] Based on the estimated results, conditional restrictions are imposed on the electrostatic force threshold of the wafer;

[0101] Based on the aforementioned constraints, the negative charge content generated by electrostatic force on the wafer is detected. When the negative charge content exceeds the preset maximum wafer load capacity, the wafer is powered off, and the processing result is obtained.

[0102] Based on the processing results, the electrostatic force of the wafer is regulated to adjust the negative charge content of the wafer within the estimated threshold range.

[0103] Based on the aforementioned constraints, when the negative charge content of the detected wafer is lower than the preset minimum wafer load capacity, the wafer is powered off, and the processing result is obtained.

[0104] Based on the processing results, the electrostatic force of the wafer is regulated to adjust the negative charge content of the wafer within the estimated threshold range.

[0105] The working principle of the above technical solution is as follows: In the existing technology, there is no setting for the adsorption force of the electrostatic chuck. Therefore, during the use of the existing electrostatic chuck, the adsorbed object may detach due to exceeding the adsorption capacity of the electrostatic chuck, which may cause damage to the equipment and injury to the operator. Therefore, the existing electrostatic chuck technology has defects. However, the corresponding technology of the present invention can solve this problem. The present technology adjusts the adsorption force of the wafer to make its adsorption force reach a reasonable adsorption threshold. After adjusting the adsorption force of the wafer, its adsorption force is limited. This limitation ensures accurate completion of the etching process. In the present invention, the condition limitation is to limit the limit value of the electrostatic force threshold of the wafer, that is, the maximum charge carrying capacity of the wafer.

[0106] The beneficial effects of the above technical solution are: by limiting the adsorption force threshold of the wafer, it can be ensured that when the adsorption range of the wafer is exceeded or lowered, equipment damage or personal injury can be avoided.

[0107] Example 5:

[0108] In one specific embodiment, based on the threshold, the actual negative charge content of the wafer is detected, and the adsorption force data generated by the negative charge on the wafer is obtained through charge analysis and calculation, including:

[0109] Based on the obtained wafer negative charge threshold, an electrostatic induction experiment was conducted on the wafer to obtain the electrostatic induction parameters of the wafer after energization.

[0110] The negative charge content of the wafer at different time periods is detected in real time using the electrostatic induction parameters, and the negative charge content is analyzed and calculated to obtain the calculation results.

[0111] Based on the calculation results, charge data values ​​are extracted, and electrostatic Coulomb force data values ​​generated by negative charge on the wafer are obtained according to the charge data values.

[0112] Based on the electrostatic Coulomb force data, the adsorption force data generated by the negative charge on the wafer is obtained by performing data calculation through the resultant force equation.

[0113] The working principle of the above technical solution is as follows: Based on the understanding of the existing technology, it can be seen that the existing electrostatic chuck technology realizes the handling of equipment by simulating the cross-section and elastic modulus of the chuck material; the technology of the present invention calculates the electrostatic force generated by the negative charge on the wafer through the calculation formula of Coulomb electrostatic force. First, the negative charge value on the wafer is detected, and then the calculation is performed based on the detection result. The wafer adsorption force data value is obtained through the resultant force equation.

[0114] The beneficial effects of the above technical solution are as follows: by obtaining the adsorption data of the wafer, and then analyzing and calculating the charge amount of the wafer at different time periods, the adsorption force obtained by the negative charge is refined, and then the adsorption force value of the wafer is obtained, thus providing a calculation method for the adsorption force of the electrostatic chuck.

[0115] Example 6:

[0116] In one specific embodiment, the real-time detection of the negative charge content of the wafer at different time periods, and the analysis and calculation of the negative charge content to obtain the calculation results, includes:

[0117] The content of negative charge in the wafer was detected at different time periods after it was powered on, and the corresponding data value of time-negative charge content was obtained;

[0118] Based on the data values ​​of the charge adsorbed on the wafer during a fixed time period and the corresponding time period, a curve of charge change over time is generated.

[0119] The negative charge of the wafer is verified over time using the curve, the charge change parameters are obtained, and the charge change parameters are stored to obtain the stored data.

[0120] Based on the stored data, the wafer negative charge content value is analyzed and calculated to obtain the calculation results;

[0121] Based on the results, data on the electrostatic force generated by the negative charge on the wafer are obtained.

[0122] The working principle of the above technical solution is as follows: by detecting the change value of the wafer's negative charge in different time periods, and then generating a curve record based on the change value of time and charge, the wafer charge situation can be clearly and intuitively observed, avoiding repeated detection and saving resources. Then, the wafer charge is verified and the verified data is stored. Then, calculations are performed based on the stored data to obtain the calculation result.

[0123] The beneficial effects of the above technical solution are as follows: Real-time detection of the charge amount of the wafer at different time periods is to obtain a curve of charge change over time. The intuitive curve can clearly reflect the change of negative charge on the wafer, which can save time and provide data change reference for subsequent calculations.

[0124] Example 7:

[0125] In one specific embodiment, the positive charge content of the electrostatic chuck is adjusted based on the adsorption force control parameter to obtain the adjustment result, including:

[0126] Based on the adsorption force data generated by the negative charge on the wafer, the adsorption force control parameters are extracted;

[0127] Based on the aforementioned adsorption force control parameters, the positive charge of the electrostatic chuck is adjusted to obtain the processing result;

[0128] Based on the processing results, determine whether the positive charge control method of the electrostatic chuck is reasonable, and obtain the judgment result;

[0129] If the judgment result is unreasonable, the power supply to the electrostatic chuck will be cut off and an alarm will be displayed.

[0130] When the judgment result is reasonable, the electrostatic chuck control parameters are extracted and the electrostatic chuck control parameters are stored.

[0131] Based on the stored data, the electrostatic force generated by the positive charge of the electrostatic chuck is calculated and analyzed to obtain the corresponding adsorption force value of the electrostatic chuck.

[0132] The working principle of the above technical solution is as follows: In the existing technology, there is no technology that adjusts the positive charge content of the electrostatic chuck based on the negative charge content of the wafer, nor is there any further rationality judgment of the adjustment method after adjustment. This is a feature lacking in the existing technology. However, in the technology of this invention, the negative charge content generated by the wafer is used as the basis for calculating the subsequent adsorption force. Then, based on the calculated adsorption force data, wafer control parameters are extracted from the data. Then, the positive charge content of the electrostatic chuck is adjusted according to the wafer control parameters. When the adjustment operation is reasonable, the electrostatic chuck adjustment parameters are extracted. Then, the adjustment parameters are error-eliminating. By eliminating the influence of error, accurate adjustment parameters can be obtained. Then, the calculated adjustment parameters are stored. Then, the stored data is analyzed and calculated again to obtain the adsorption force of the electrostatic chuck. This technical solution can eliminate the negative charge content of the wafer.

[0133] The beneficial effects of the above-mentioned technical solution are as follows: by adjusting the positive charge of the electrostatic chuck according to the control parameters of the wafer, and then calculating and extracting the adjustment parameters of the electrostatic chuck to obtain the adsorption force between the electrostatic chuck and the wafer, this operation can make the control of the electrostatic chuck to operate the wafer for etching more precise.

[0134] Example 8:

[0135] In one specific embodiment, when adjusting the positive charge of the electrostatic chuck, the adjustment method is judged, and then processed according to the judgment result. If the judgment result is reasonable, the adjustment parameters are extracted. The specific calculation method of the adjustment parameters is as follows:

[0136]

[0137] Among them, R (x)Indicates the control parameter; B (x) Indicates wafer control parameters; γ (x) The adsorption force parameter is represented by x; x is the total control variable for the wafer; x i Let i be the i-th control variable out of a total of n variables; This represents the product of the difference between the total control variable and the i-th control variable; θ represents the charge action; δ represents the electrostatic chuck adsorption force parameter; f(x) represents the electrostatic chuck adsorption force.

[0138] Error elimination calculations are performed based on the calculated control parameters. This error elimination makes the control parameters more accurate, and then the control parameters are used to precisely control the subsequent calculation of the positive charge content on the electrostatic chuck. The specific error elimination process for the control parameters is shown below:

[0139]

[0140] Where σ is the error factor; β (0) This represents the error value in the electrostatic chuck control process. By eliminating the influence of error, accurate control parameters can be obtained. Then, the calculated control parameters are stored, and the stored data is analyzed and calculated again to obtain the adsorption force of the electrostatic chuck.

[0141] Example 9:

[0142] In one specific embodiment, the alarm display includes:

[0143] The alarm display is divided into three categories: abnormal control alarm, abnormal temperature alarm, and leakage current alarm.

[0144] When an abnormal control alarm occurs, a voice alarm prompt for abnormal control is issued, and an alarm record is generated and stored in the database.

[0145] When a temperature abnormality alarm occurs, a temperature abnormality LED flashing alarm is activated, and an alarm record is generated and stored in the database.

[0146] When a leakage current alarm occurs, alternating voice alarm and flashing light alarm will be provided, and an alarm record will be generated and stored in the database.

[0147] The working principle of the above technical solution is as follows: In the existing technology, electrostatic chucks do not involve alarm prompts. When an electrostatic chuck malfunctions, the problem cannot be detected in time, which may damage the electrostatic chuck and the equipment it adsorbs and grasps, thus wasting resources. In this technology, corresponding alarm prompts are provided for possible problems such as abnormal temperature, leakage, and abnormal control of the electrostatic chuck. This allows operators to detect problems in a timely manner and perform inspection and repair. Different alarm prompts for different problems make it easier for operators to distinguish the problems, thereby minimizing the loss of equipment resources. This is a risk warning that existing technologies cannot achieve.

[0148] The beneficial effects of the above technical solution are as follows: the alarm display can promptly display alarms for abnormal situations that occur during the control of the electrostatic chuck, thereby enabling the abnormal problems to be dealt with as soon as possible and reducing equipment losses caused by abnormal problems.

[0149] Example 10:

[0150] In one specific embodiment, based on the control result, the positive charge of the electrostatic chuck is matched equally with the negative charge of the wafer, and the electrostatic chuck is controlled to operate the wafer for etching operations, including:

[0151] Based on the acquisition of electrostatic chuck adsorption force and wafer adsorption force, control rules for electrostatic chuck and wafer adsorption force are formulated.

[0152] According to the control rules, the temperature during the adsorption of the electrostatic chuck and the wafer is detected, and the temperature detection results are obtained.

[0153] Based on the temperature detection results, the electrostatic chuck and wafer are adjusted to eliminate the influence of temperature error on the adhesion force of the electrostatic chuck and wafer.

[0154] By eliminating temperature errors, the positive charge of the electrostatic chuck is matched equally with the negative charge of the wafer to obtain accurate adhesion between the electrostatic chuck and the wafer.

[0155] Based on the adsorption force, the electrostatic chuck is controlled to operate the wafer for etching operations;

[0156] The working principle of the above technical solution is as follows: Existing technology combines an electrostatic chuck and a DC electrode and calculates the electrostatic force required to overcome the deformation of the wafer 20 based on the initial suction force and the deformation generated during the wafer 20 process. Then, the direction of the suction force is determined to control the electrostatic chuck. This technology is prone to inaccurate control of the electrostatic chuck due to the difficulty in obtaining the deformation amount. However, in this technology, by formulating the adsorption force rules between the electrostatic chuck and the wafer, and further detecting the temperature change of the electrostatic chuck's adsorption force during the adsorption process, the adsorption error caused by temperature influence is eliminated according to the corresponding adsorption force rules, thereby controlling the electrostatic chuck to operate the wafer to complete the etching task.

[0157] The beneficial effects of the above technical solution are as follows: by eliminating the error in the adsorption force between the electrostatic chuck and the wafer caused by temperature, it is possible to ensure the accurate completion of the adsorption etching task and to ensure the safety of the electrostatic chuck and the wafer during the operation.

[0158] Example 11:

[0159] In one specific embodiment, obtaining the temperature detection result includes:

[0160] When the detection result shows a normal state, the detected temperature data is stored, and a temperature change curve is generated based on the temperature data;

[0161] When the detection result shows an abnormal state, a temperature abnormality alarm will be issued;

[0162] Based on the aforementioned temperature anomaly alarm, temperature anomaly analysis is performed, and temperature anomaly solutions are formulated.

[0163] Based on the aforementioned temperature anomaly solution, the electrostatic chuck and wafer were subjected to cooling and insulation treatment, and the treatment results were obtained.

[0164] Based on the processing results, feedback is provided, and the feedback results are obtained.

[0165] The working principle of the above technical solution is as follows: This technology can quickly determine the temperature change of the electrostatic chuck and wafer during the adsorption process by detecting the temperature of the electrostatic chuck and wafer. For example, the obtained temperature change can determine whether the electrostatic chuck and wafer are working under normal operating conditions. When the detected temperature is higher than the normal temperature value of the electrostatic chuck and wafer, the power of the electrostatic chuck and wafer can be cut off. The cause of the abnormal temperature can be detected and the problem can be dealt with. At the same time, an alarm is triggered when the abnormal temperature is detected. Feedback is given based on the processing results to facilitate subsequent handling of this problem.

[0166] The beneficial effects of the above technical solution are as follows: During the etching process of using an electrostatic chuck to operate a wafer, the temperature of the electrostatic chuck and the wafer is monitored. Since the electrostatic chuck and the wafer generate electrostatic force through the attraction of charge transfer, energy conversion and heat generation occur during the generation of charge. Therefore, the accuracy of controlling the etching process of the wafer by the electrostatic chuck is affected by temperature. Thus, temperature detection of the electrostatic chuck can keep track of the temperature change of the electrostatic chuck at any time, and the temperature can be adjusted in a timely manner according to the changes, thereby reducing losses caused by excessive temperature.

[0167] Example 12:

[0168] In one specific embodiment, the power supply comprises a regulated power supply and a frequency converter; wherein,

[0169] The regulated power supply is used to supply voltage to the electrostatic chuck and to compensate for voltage fluctuations.

[0170] The frequency converter is used to adjust the voltage frequency in the circuit. According to the voltage requirements when the electrostatic chuck is adsorbed by the wafer, the frequency converter is used to regulate the circuit voltage.

[0171] Based on the aforementioned control process, the voltage required for etching the wafer by the electrostatic chuck is obtained;

[0172] The regulated power supply and the frequency converter are combined and packaged to generate a power supply for the electrostatic chuck.

[0173] The working principle of the above technical solution is as follows: The above technology combines and packages a regulated power supply and a frequency converter to form a power supply for an electrostatic chuck, and then controls the electrostatic chuck to operate the wafer to complete the etching work.

[0174] The beneficial effects of the above technical solution are as follows: In the case of aging power configuration or unstable circuit, the use of a voltage stabilizer can make up for the waste of resources caused by voltage instability, and at the same time prevent the occurrence of safety accidents that may be caused by voltage instability; the frequency converter provides the most suitable voltage for the adsorption of electrostatic chuck and wafer, ensuring that the electrostatic chuck and wafer can work stably and improving their working efficiency.

[0175] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A control method for an electrostatic chuck used in an etching machine, characterized in that, include: Based on the wafer's rated specifications, a wafer charge detection demonstration was conducted to estimate the threshold for the wafer to carry negative charge. Based on the threshold, the actual negative charge content of the wafer is detected, and the adsorption force data generated by the negative charge of the wafer is obtained through charge analysis and calculation. Based on the adsorption force data, adsorption force control parameters are extracted, and the positive charge content of the electrostatic chuck is adjusted based on the adsorption force control parameters to obtain the adjustment result. Based on the control results, the positive charge of the electrostatic chuck is matched equally with the negative charge of the wafer, and the electrostatic chuck is controlled to operate the wafer for etching. Based on the aforementioned control results, the positive charge of the electrostatic chuck is matched equally with the negative charge of the wafer to control the electrostatic chuck to operate the wafer for etching operations, including: Obtain the electrostatic chuck adsorption force and wafer adsorption force, and formulate control rules for the electrostatic chuck and wafer adsorption force; According to the control rules, the temperature during the adsorption of the electrostatic chuck and the wafer is detected, and the temperature detection results are obtained. Based on the temperature detection results, the electrostatic chuck and wafer are adjusted to eliminate the influence of temperature error on the adhesion force of the electrostatic chuck and wafer. By eliminating temperature errors, the positive charge of the electrostatic chuck is matched equally with the negative charge of the wafer to obtain accurate adhesion between the electrostatic chuck and the wafer. Based on the adsorption force, the electrostatic chuck is controlled to operate the wafer for etching operations.

2. The control method for an electrostatic chuck used in an etching machine as described in claim 1, characterized in that, The demonstration operation of wafer charge detection based on the wafer's rated specifications, and the estimation of the threshold for the wafer to bear negative charge, includes: Based on the wafer's rated specifications, obtain the wafer's conductivity parameters. Based on the conductivity parameter data, the energizing voltage and current are limited to obtain the electric field strength value of the wafer. An electrostatic force is generated based on the electric field strength value, and the negative charge generated by the electrostatic force is detected. By calculating the negative charge content of the wafer, the electrostatic adsorption force of the wafer within a reasonable range is determined, and the electrostatic adsorption data of the wafer is obtained. Based on the wafer electrostatic adsorption data, conditions are imposed, and the negative charge carrying threshold of the wafer is estimated through these conditions.

3. The control method for an electrostatic chuck used in an etching machine as described in claim 2, characterized in that, Conditions are imposed based on the wafer electrostatic adsorption data, including: Based on the obtained wafer electric field strength, the electrostatic force threshold of the wafer is estimated, and the estimation result is obtained. Based on the estimated results, conditional restrictions are imposed on the electrostatic force threshold of the wafer; Based on the aforementioned constraints, the negative charge content generated by electrostatic force on the wafer is detected. When the negative charge content exceeds the preset maximum wafer carrying capacity, the wafer is powered off. The processing result is obtained, and the electrostatic force on the wafer is adjusted according to the processing result to bring the negative charge content of the wafer within the estimated threshold range. Based on the aforementioned constraints, when the detected negative charge content of the wafer is lower than the preset minimum wafer load capacity, the wafer is powered off, the processing result is obtained, and the electrostatic force of the wafer is adjusted according to the processing result to bring the negative charge content of the wafer within the estimated threshold range.

4. The control method for an electrostatic chuck used in an etching machine as described in claim 1, characterized in that, Based on the threshold, the actual negative charge content of the wafer is detected, and the adsorption force data generated by the negative charge on the wafer is obtained through charge analysis and calculation, including: Based on the obtained wafer negative charge threshold, an electrostatic induction experiment was conducted on the wafer to obtain the electrostatic induction parameters of the wafer after energization. The negative charge content of the wafer at different time periods is detected in real time using the electrostatic induction parameters, and the negative charge content is analyzed and calculated to obtain the calculation results. Based on the calculation results, charge data values ​​are extracted, and electrostatic Coulomb force data values ​​generated by negative charge on the wafer are obtained according to the charge data values. Based on the electrostatic Coulomb force data, the adsorption force data generated by the negative charge on the wafer is obtained by performing data calculation through the resultant force equation.

5. The control method for an electrostatic chuck used in an etching machine as described in claim 4, characterized in that, The method involves real-time detection of the negative charge content of the wafer at different time periods, analysis and calculation of the negative charge content, and obtaining calculation results, including: The content of negative charge in the wafer was detected at different time periods after it was powered on, and the corresponding data value of time-negative charge content was obtained; Based on the data values ​​of the charge adsorbed on the wafer during a fixed time period and the corresponding time period, a curve of charge change over time is generated. The negative charge of the wafer is verified over time using the curve, the charge change parameters are obtained, and the charge change parameters are stored to obtain the stored data. Based on the stored data, the wafer negative charge content value is analyzed and calculated to obtain the calculation results; Based on the results, data on the electrostatic force generated by the negative charge on the wafer are obtained.

6. The control method for an electrostatic chuck used in an etching machine as described in claim 1, characterized in that, The positive charge content of the electrostatic chuck is adjusted based on the adsorption force control parameters to obtain the adjustment results, including: Based on the adsorption force data generated by the negative charge on the wafer, the adsorption force control parameters are extracted; Based on the aforementioned adsorption force control parameters, the positive charge of the electrostatic chuck is adjusted to obtain the processing result; Based on the processing results, determine whether the positive charge control method of the electrostatic chuck is reasonable, and obtain the judgment result; If the judgment result is unreasonable, the power supply to the electrostatic chuck will be cut off and an alarm will be displayed. When the judgment result is reasonable, the electrostatic chuck control parameters are extracted and the electrostatic chuck control parameters are stored. Based on the stored data, the electrostatic force generated by the positive charge of the electrostatic chuck is calculated and analyzed to obtain the corresponding adsorption force value of the electrostatic chuck.

7. The control method for an electrostatic chuck used in an etching machine as described in claim 6, characterized in that, The alarm display includes: The alarm display is divided into three categories: abnormal control alarm, abnormal temperature alarm, and leakage current alarm. When an abnormal control alarm occurs, a voice alarm prompt for abnormal control is issued, and an alarm record is generated and stored in the database. When a temperature abnormality alarm occurs, a temperature abnormality LED flashing alarm is activated, and an alarm record is generated and stored in the database. When a leakage current alarm occurs, alternating voice and flashing light alarms are provided, and an alarm record is generated and stored in the database.

8. The control method for an electrostatic chuck used in an etching machine as described in claim 1, characterized in that, The acquisition of temperature detection results includes: When the detection result shows a normal state, the detected temperature data is stored, and a temperature change curve is generated based on the temperature data; When the detection result shows an abnormal state, a temperature abnormality alarm will be issued; Based on the temperature anomaly alarm, temperature anomaly analysis is performed, and temperature anomaly solutions are formulated. According to the temperature anomaly solution, the electrostatic chuck and wafer are subjected to cooling and insulation treatment, and the treatment results are obtained. Based on the treatment results, the treatment results are fed back and the feedback results are obtained.

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