Temperature control method and heating plate temperature control system

Abstract

The invention provides a temperature control method, a heating plate temperature control system and a computer readable storage medium. The temperature control method comprises the following steps: acquiring a working condition state of semiconductor processing equipment; in response to the condition that the working condition state indicates that the semiconductor processing equipment is not subjected to heating wire resistance-temperature curve calibration, adopting a first control mode, and performing temperature measurement through a thermocouple arranged in a central area of a heating disc of the semiconductor processing equipment so as to perform temperature control and heating wire resistance-temperature curve calibration on the heating disc; and in response to the condition state, indicating that the semiconductor processing equipment has been calibrated by the heating wire resistance-temperature curve, adopting a second control mode to measure the resistance of the heating wire in the heating plate, and performing temperature measurement and temperature control on the heating plate in combination with the heating wire resistance-temperature curve.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a temperature control method, a heating plate temperature control system, and a computer-readable storage medium. Background Technology

[0002] In precision machining fields such as semiconductor manufacturing, the heating plate, as a core temperature control component, directly determines process accuracy and product yield through its operational stability. Various typical operating conditions exist during equipment operation, including startup heating, steady-state process execution, process switching transitions, and shutdown cooling. The heat load distribution, temperature response requirements, and thermal stress state of the heating plate differ significantly under these different conditions. For example, during startup, it is necessary to quickly reach the target temperature while avoiding thermal shock; during steady-state operation, temperature uniformity must be maintained; and during process switching, dynamic temperature adjustments must be accommodated. These conditions place specific demands on the temperature control strategy of the heating plate.

[0003] However, most existing heating plate control technologies employ a fixed, uniform heating mode to handle all operating conditions, failing to consider the differentiated needs under various conditions. This single control method struggles to adapt to changes in thermal characteristics under different operating conditions, easily leading to excessive localized temperature deviations, abnormal heating or cooling rates, and consequently, thermal stress concentration. Over long-term operation, the accumulation of thermal stress significantly increases the risk of heating plate breakage, causing not only equipment downtime and increased production costs but also potential impacts on the process environment due to fragmentation, resulting in product scrap and severely restricting production efficiency and equipment reliability.

[0004] In order to overcome the above-mentioned defects in the existing technology, there is an urgent need in the field for a temperature control technology to avoid the thermal stress risk caused by a single heating mode, thereby improving the operational stability of the heating plate and reducing the risk of fragmentation. Summary of the Invention

[0005] The following provides a brief overview of one or more aspects to offer a basic understanding of them. This overview is not an exhaustive summary of all conceived aspects, nor is it intended to identify key or decisive elements of all aspects, nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed descriptions that follow.

[0006] To overcome the aforementioned deficiencies in the prior art, the present invention provides a temperature control method, a heating plate temperature control system, and a computer-readable storage medium to avoid the thermal stress risk caused by a single heating mode, thereby improving the operational stability of the heating plate and reducing the risk of fragmentation.

[0007] Specifically, the temperature control method according to the first aspect of the present invention includes the following steps: acquiring the operating condition status of a semiconductor processing equipment; in response to the operating condition status indicating that the semiconductor processing equipment has not been calibrated using a heating wire resistance-temperature curve, adopting a first control mode, and measuring the temperature of the heating plate via a thermocouple located in the central region of the heating plate of the semiconductor processing equipment, so as to perform temperature control and heating wire resistance-temperature curve calibration of the heating plate; and

[0008] In response to the operating condition indicating that the semiconductor processing equipment has been calibrated by the heating wire resistance-temperature curve, a second control mode is adopted to measure the resistance of the heating wire in the heating plate and to perform temperature measurement and temperature control on the heating plate in combination with the heating wire resistance-temperature curve.

[0009] Furthermore, in some embodiments of the present invention, the step of measuring temperature via a thermocouple disposed in the central region of the heating plate of the semiconductor processing equipment to control the temperature of the heating plate and calibrate the resistance-temperature curve of the heating wire includes: obtaining the highest target temperature of the heating plate, a preset temperature rise step, and a preset isothermal interval; gradually increasing the first power supplied to the first heating wire disposed in the central region, and collecting the first temperature of the central region at different times to control the central region within the range below the highest target temperature, and maintaining the temperature for one isothermal interval for each temperature rise step; collecting the first voltage and first current of the first heating wire at each isothermal interval to calculate its first resistance value; and calibrating its first resistance-temperature mapping curve based on the first resistance value and first temperature of the first heating wire at each isothermal interval.

[0010] Furthermore, in some embodiments of the present invention, the step of measuring temperature via a thermocouple disposed in the central region of the heating plate of the semiconductor processing equipment to control the temperature of the heating plate and calibrate the resistance-temperature curve of the heating wire further includes: providing a second power to a second heating wire disposed in the edge region of the heating plate according to a preset control ratio, synchronously with the first power, wherein the control ratio is (0.8, 1); acquiring the second voltage and second current of the second heating wire at the end of each of the constant temperature intervals to calculate its second resistance value; and calibrating the second resistance-temperature mapping curve of the second heating wire based on the second resistance value of the second heating wire at the end of each of the constant temperature intervals and the first temperature at the corresponding constant temperature interval.

[0011] Furthermore, in some embodiments of the present invention, the step of employing a second control mode to measure the resistance of the heating wire in the heating plate and to perform temperature measurement and temperature control on the heating plate in combination with the heating wire resistance-temperature curve includes: measuring the first resistance of the first heating wire; determining the first temperature of the central region based on the first resistance and the first resistance-temperature mapping curve; and determining the first power output to the first heating wire based on the difference between the first temperature and the first target temperature of the central region.

[0012] Furthermore, in some embodiments of the present invention, the step of using a second control mode to measure the resistance of the heating wire in the heating plate and using the heating wire resistance-temperature curve to measure and control the temperature of the heating plate further includes: in response to the operating condition indicating that the current temperature rise is based on the second control mode, using a first sub-control mode, determining a second power to be provided to the second heating wire located in the edge region of the heating plate according to the first power and a preset control ratio, wherein the control ratio is (0.8, 1).

[0013] Furthermore, in some embodiments of the present invention, the step of employing a second control mode to measure the resistance of the heating wire in the heating plate and using the heating wire resistance-temperature curve to perform temperature measurement and temperature control on the heating plate further includes: in response to the operating condition indicating that the current temperature rise is not based on the second control mode, employing a second sub-control mode, measuring the second resistance of the second heating wire, and using the corresponding second resistance-temperature mapping curve to determine the second temperature of the edge region; and determining the second power output to the second heating wire based on the difference between the second temperature and the second target temperature of the edge region.

[0014] Furthermore, in some embodiments of the present invention, the temperature control method further includes the following steps: in the second sub-control mode, determining whether the difference between the second temperature and the first temperature is within a preset temperature difference threshold; in response to the difference exceeding the temperature difference threshold, switching back to the first sub-control mode, and re-determining the second power supplied to the second heating wire according to the first power and the preset control ratio.

[0015] Furthermore, in some embodiments of the present invention, the temperature control method further includes the following steps: in the second control mode, measuring the temperature of the heating plate and its rate of change, as well as the output power to the heating wire in the heating plate, to determine whether the second control mode is abnormal; and in response to the determination result that the second control mode is abnormal, switching to the first control mode, and measuring the temperature via the thermocouple to control the temperature of the heating plate.

[0016] Furthermore, in some embodiments of the present invention, the temperature control method further includes the following steps: after completing the calibration of the heating wire resistance-temperature curve, measuring the temperature of the heating plate and its slope of change in the first control mode, as well as the output power to the heating wire in the heating plate, to determine whether the first control mode is abnormal; and in response to the determination result that the first control mode is abnormal, switching to the second control mode, and measuring and controlling the temperature of the heating plate through the resistance of the heating wire and the heating wire resistance-temperature curve.

[0017] Furthermore, the heating plate temperature control system provided according to the second aspect of the present invention includes: a thermocouple disposed in the central region of the heating plate; a voltage and current sampling circuit connected to the heating wire in the heating plate to measure its resistance; and a controller configured to perform the temperature control method as described in any one of the first aspects of the present invention.

[0018] Furthermore, according to the third aspect of the present invention, a computer-readable storage medium is provided thereon storing computer instructions. When the computer instructions are executed by a processor, the temperature control method as described in any one of the first aspects of the present invention is implemented. Attached Figure Description

[0019] The above-described features and advantages of the present invention will be better understood after reading the following detailed description of embodiments of the present disclosure in conjunction with the accompanying drawings. In the drawings, components are not necessarily drawn to scale, and components having similar related characteristics or features may have the same or similar reference numerals.

[0020] Figure 1 A schematic diagram of the partitioning of a heating plate is shown.

[0021] Figure 2 This is a schematic diagram of another type of heating plate partition.

[0022] Figure 3 This is a schematic diagram of another type of heating plate partition.

[0023] Figure 4 This is a schematic diagram of the heating system according to an embodiment of the present invention.

[0024] Figure 5 This is a flowchart of a temperature control method for a wafer heating plate according to an embodiment of the present invention.

[0025] Figure 6 This is a flowchart illustrating the construction process of the mathematical model in an embodiment of the present invention.

[0026] Figure 7 This is a flowchart illustrating the construction process of the resistance thermometer model according to an embodiment of the present invention.

[0027] Figure 8 This is a flowchart illustrating the generation process of the resistance thermometer model according to an embodiment of the present invention.

[0028] Figure 9 This is a flowchart of another method for temperature control of a wafer heating plate according to an embodiment of the present invention.

[0029] Figure 10 This is a comparison chart of the output temperature of the mathematical model in an embodiment of the present invention and the actual measured temperature.

[0030] Figure 11 This is a schematic diagram of the temperature calculated based on resistance and the actual measured temperature according to an embodiment of the present invention.

[0031] Figure 12 A schematic flowchart of a temperature control method according to some embodiments of the present invention is shown.

[0032] Figure 13 A flowchart illustrating a method for monitoring the temperature of a heating plate according to some embodiments of the present invention is shown.

[0033] Figure 14 A schematic diagram of the process for training the anomaly alarm model according to some embodiments of the present invention is shown.

[0034] Figure 15 This is a schematic diagram of the hardware connection when calibrating the output voltage and current of the driver according to an embodiment of the present invention.

[0035] Figure 16 This is a flowchart illustrating the calibration of the driver output voltage and current according to an embodiment of the present invention.

[0036] Figure 17 This is a schematic diagram of the hardware connection of the thermocouple sensor in the calibration process according to an embodiment of the present invention.

[0037] Figure 18 This is a flowchart of the calibration of the thermocouple sensor and the voltage acquisition process according to an embodiment of the present invention.

[0038] Figure 19 This is a structural block diagram of the temperature control device for the wafer heating plate according to an embodiment of the present invention.

[0039] Figure 20 This is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. Detailed Implementation

[0040] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Although the description of the present invention is presented in conjunction with preferred embodiments, this does not mean that the features of the invention are limited to these embodiments. On the contrary, the purpose of describing the invention in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of the present invention. To provide a thorough understanding of the invention, many specific details will be included in the following description. The invention may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of the invention, some specific details will be omitted in the description.

[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0042] Furthermore, the terms "upper," "lower," "left," "right," "top," "bottom," "horizontal," and "vertical" used in the following description should be understood as the orientations shown in the relevant paragraphs and accompanying drawings. These relative terms are for illustrative purposes only and do not imply that the described apparatus must be manufactured or operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0043] It is understood that although terms such as "first," "second," and "third" may be used herein to describe various components, regions, layers, and / or parts, these components, regions, layers, and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers, and / or parts. Therefore, the first components, regions, layers, and / or parts discussed below may be referred to as second components, regions, layers, and / or parts without departing from some embodiments of the present invention.

[0044] As mentioned above, most existing heating plate control technologies employ a fixed and uniform heating mode to handle all operating conditions, failing to consider the differentiated needs under different conditions. This single control method struggles to adapt to changes in thermal characteristics under various operating conditions, easily leading to excessive local temperature deviations, abnormal heating or cooling rates, and consequently, thermal stress concentration. Over long-term operation, the accumulation of thermal stress significantly increases the risk of heating plate breakage, causing not only equipment downtime and increased production costs but also potential impacts on the process environment due to fragmentation, resulting in product scrap and severely restricting production efficiency and equipment reliability.

[0045] To overcome the aforementioned deficiencies in the prior art, the present invention provides a temperature control method, a heating plate temperature control system, and a computer-readable storage medium to avoid the thermal stress risk caused by a single heating mode, thereby improving the operational stability of the heating plate and reducing the risk of fragmentation.

[0046] Please refer to the details. Figures 1-4 , Figure 1 A schematic diagram of the partitioning of a heating plate is shown. Figure 2 This is a schematic diagram of another type of heating plate partition. Figure 3 This is a schematic diagram of another type of heating plate partition. Figure 4 This is a schematic diagram of the heating system according to an embodiment of the present invention.

[0047] like Figure 1 and Figure 2 As shown, the relevant scheme divides the heating plate into several regions, with a corresponding thermistor heating element embedded in each region, and the heating plate is heated by this thermistor heating element. For each region within the multiple regions, an RT table model corresponding to temperature and resistance is established. The temperature is obtained by looking up the table model, thereby controlling the heating power. This scheme relies on table lookup to obtain temperature data, making it difficult to adapt to complex temperature changes, resulting in limited control accuracy. Furthermore, it relies on temperature sensors for temperature measurement, leading to problems such as high cost, slow response, and susceptibility to environmental influences.

[0048] In view of this, the present invention proposes a method for temperature control of a wafer heating plate.

[0049] According to an embodiment of the present invention, a method for temperature control of a wafer heating plate is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0050] This embodiment provides a temperature control method for a wafer heating plate, used in a controller within a heating system. Combined with... Figure 3 and Figure 4 Taking a dual-zone heating plate as an example, the heating system includes two single-zone drivers, a controller and a host computer. The controller outputs heating power through each single-zone driver to control the temperature of each zone.

[0051] Please refer to Figure 5 , Figure 5 This is a flowchart of a temperature control method for a wafer heating plate according to an embodiment of the present invention.

[0052] like Figure 5As shown, the temperature control method for the wafer heating disk in this embodiment of the invention includes the following steps:

[0053] Step S501: Obtain the preset temperature control parameters and the resistance parameters of the thermistor heating element set inside the target heating zone in the heating plate.

[0054] Specifically, the thermistor heating element uses a thermocouple sensor.

[0055] The preset temperature parameters include at least one of power and environmental parameters. The power can be calculated by measuring the current and voltage of the thermistor heating element, while the environmental parameters are obtained by detecting the temperature using a temperature sensor.

[0056] Step S502: According to the preset standard, select either to obtain the real-time temperature of the target heating zone based on the resistance parameters and the pre-built resistance thermometer model, or to obtain the real-time temperature based on the resistance parameters, preset temperature control parameters and the pre-built mathematical model. The input of the mathematical model is the resistance parameters and the preset temperature control parameters, and the output is the real-time temperature. The mathematical model is constructed by using a system identification method.

[0057] Specifically, in the mathematical model, mathematical equations are used to represent the output and the relationship between them, so that the corresponding output can be calculated after the input is obtained. For example, in this application, there is a linear relationship between the resistance parameter, the preset temperature control parameter, and the real-time temperature. Based on this linear relationship, the optimal mathematical model is selected by system identification.

[0058] Depending on the actual situation, the use of the mathematical model and the temperature resistance meter model can be switched. A single method or a combination of both methods can be used for comparison.

[0059] Among these, the resistance thermometer model is well-suited for environments with minimal changes. In such cases, using a lookup table—that is, finding the corresponding temperature based on the resistance parameters—makes temperature monitoring simpler and more convenient. However, the lookup table method generally cannot achieve very high precision, for example, in situations with very low resolution. In such cases, a mathematical model is needed to obtain the real-time temperature.

[0060] Step S503: Adjust the heating power of the target heating zone according to the real-time temperature so that the real-time temperature reaches the target temperature.

[0061] Specifically, after obtaining the real-time temperature of each zone, proportional-integral-derivative (PID) control is performed based on the real-time temperature to control the heating power of the heating plate, so that the temperature of each zone rises at a set rate / set power to reach the specified target temperature.

[0062] In some embodiments, a uniform temperature control algorithm or an adaptive coupling coefficient dynamic adjustment algorithm is used to adjust the heating power of the target heating zone so that the real-time temperature reaches the target temperature.

[0063] by Figure 1 For example, this area has a three-zone heating plate. We will use this as an example to illustrate the multi-zone plate temperature control algorithm. First, the surface temperature of each heating zone is calculated based on the resistance according to the lookup table model or system model. Then, calculate the weighted average temperature. = (T1+T2+T3) / 3, calculate the temperature deviation Based on the current temperature deviation, it determines whether power needs to be increased, generates control quantities, performs constraint processing, and outputs the results to achieve uniform temperature control, ensuring that the temperature difference between T1, T2, and T3 is within a certain range, thus achieving uniform temperature control.

[0064] The algorithm flow is as follows:

[0065] Initialization: Set the target temperature;

[0066] The plate temperatures T1, T2, and T3 were calculated.

[0067] Calculate the weighted average temperature;

[0068] Calculate the average temperature deviation;

[0069] Generate a comprehensive control input or use an adaptive coupling coefficient as the control input;

[0070] Perform constraint processing;

[0071] Output control;

[0072] Weighted average temperature calculation:

[0073]

[0074] in, The weighted average temperature; Let i be the temperature of the i-th region; is the weighting coefficient for the i-th region (considering factors such as heat capacity and area); n is the total number of heating regions;

[0075] Temperature deviation calculation:

[0076]

[0077] The deviation between the i-th region and the average temperature;

[0078] Basic adjustment calculation:

[0079]

[0080] is the base power adjustment for region i; β is the global adjustment gain coefficient; f(·) is the nonlinear adjustment function;

[0081]

[0082] K is the adjustment curve steepness coefficient;

[0083] The thermal coupling compensation term is:

[0084]

[0085] This represents the thermal coupling compensation amount for the i-th region; is the thermal coupling coefficient between region i and region j;

[0086] Calculate the comprehensive control quantity :

[0087]

[0088] Output power is controlled based on comprehensive control variables.

[0089] Alternatively, an adaptive coupling coefficient dynamic adjustment algorithm can be used, as follows:

[0090]

[0091] The dynamic coupling coefficient between region i and region j at time k is used as the power output coefficient.

[0092] The basic coupling coefficient reflects the heat conduction characteristics caused by the inherent structure of the heating plate;

[0093] This represents the power adjustment required for region i to reach a new steady state when the power in region j undergoes a step change.

[0094] Let J be the temperature change in region j.

[0095] This is the instantaneous temperature difference term. When a sudden temperature difference occurs in adjacent regions (such as a sudden temperature rise in region j), this term immediately increases the coupling coefficient to compensate for the thermal diffusion effect in advance. The proportionality coefficient is... Determine the compensation sensitivity;

[0096] This is a cumulative temperature difference term to address the problem of continuous accumulation of small temperature differences caused by thermal inertia.

[0097] Based on dynamic coupling coefficient Control the output power.

[0098] The temperature control method for the wafer heating plate of the present invention obtains preset temperature control parameters and resistance parameters of the thermistor heating element set inside the target heating area in the heating plate. According to preset standards, it selects to obtain the real-time temperature of the target heating area based on the resistance parameters and a pre-built resistance temperature table model, or based on the resistance parameters, preset temperature control parameters and a pre-built mathematical model. The mathematical model is input to the resistance parameters and preset temperature control parameters, and outputs the real-time temperature. The mathematical model is constructed by using a system identification method, which can obtain accurate real-time temperature. Then, the heating power of the target heating area is adjusted according to the real-time temperature to make the real-time temperature reach the target temperature. By selecting two models to obtain the real-time temperature according to the actual situation, it can adapt to complex temperature change conditions, thereby improving control accuracy.

[0099] Please refer to Figure 6 , Figure 6 This is a flowchart illustrating the construction process of the mathematical model in an embodiment of the present invention.

[0100] In some embodiments, such as Figure 6 As shown, the steps for constructing a mathematical model include:

[0101] Step S601: Obtain several sets of surface temperatures of the target heating zone, as well as the resistance parameters and preset temperature control parameters at each set of surface temperatures.

[0102] Specifically, the voltage and current parameters collected from the target heating area are calibrated; the heating plate is controlled to heat up at a constant rate, and the surface temperature of the target heating area at different times is collected; the calibrated voltage, current, and preset temperature control parameters of the target heating area at different surface temperatures are collected; and the resistance parameters are calculated based on the voltage and current parameters.

[0103] Please refer to Figure 8 , Figure 8 This is a flowchart illustrating the generation process of the resistance thermometer model according to an embodiment of the present invention.

[0104] like Figure 8 As shown, the purpose of calibrating the voltage and current parameters is to accurately calibrate the driver's output voltage and current, enabling precise calculations for subsequent temperature control. After clicking the automatic voltage and current calibration button on the host computer, the controller sends a command to the driver. The driver will slowly increase the current and voltage from zero to their maximum values. Simultaneously, the driver will send the current current channel ADC data, all voltage channel ADC data, and actual measurement data to the host computer. The host computer will record the current data. Once the host computer has finished recording, the driver automatically shuts off the output, establishing the relationship between the voltage / current and the actual control signal, and writes this relationship into the driver. At this point, the automatic calibration is complete.

[0105] By calibrating the voltage and current parameters, the accuracy of the collected data was improved, and by controlling the heating plate to heat up at a constant rate, comprehensive and systematic data samples could be collected at different temperature points.

[0106] Step S602: Systematically identify the resistance parameters, preset temperature control parameters, and surface temperature to obtain the target mathematical relationship between the resistance parameters and preset temperature control parameters of the target heating zone and the surface temperature.

[0107] Specifically, the resistance parameters, preset temperature control parameters, and surface temperature are identified to obtain several initial mathematical relationships between the resistance parameters and preset temperature control parameters of the target heating zone and the surface temperature; the prediction error of the initial mathematical relationships is verified, and the initial mathematical relationship with the smallest prediction error is taken as the target mathematical relationship.

[0108] The prediction error is the difference between the predicted value calculated based on the initial mathematical relationship and the actual value.

[0109] By selecting the optimal initial mathematical relationship to construct a mathematical model, such as a linear relationship, and constructing a linear model based on this linear relationship as the final mathematical model, the mathematical model can better reflect the actual temperature characteristics of the heating zone, thereby improving the model's performance and adaptability.

[0110] Step S603: Establish a mathematical model based on the target mathematical relationship.

[0111] Specifically, the mathematical model adopts a Multiple Input Single Output (MISO) model, with preset temperature control parameters including power parameters. The MISO model can comprehensively consider the influence of multiple input parameters on temperature, enabling the model to more fully reflect the temperature change pattern of the heating zone. Using the power parameter as input can more directly reflect the control effect of heating power on temperature, improving the model's ability to describe the temperature control process and its control effect.

[0112] In one embodiment, the preset temperature control parameters include power parameters and environmental parameters.

[0113] By incorporating ambient temperature into the preset temperature control parameters, the impact of environmental factors on the heating zone temperature can be considered more comprehensively, thereby improving the accuracy of temperature measurement and control.

[0114] The identification process of the mathematical model in this application will be illustrated below with a specific example:

[0115] After testing the system and acquiring all data (resistance parameters, preset temperature control parameters, and surface temperature), an identification algorithm is used to process the data centrally to obtain estimated values ​​of the model parameters. This method is called offline identification. Online identification, on the other hand, requires knowledge of the model's structure and order. When new input and output data are obtained, a recursive identification method is used to correct the original parameter estimates to obtain new parameter estimates.

[0116] Taking this experiment as an example, the experiment was divided into black boxes according to the provided experimental information, and the identification method was offline identification. The heating plate was a dual-zone heating plate, the mathematical model was a multiple-input single-output (MISO) mathematical model, and the preset temperature control parameters included power parameters.

[0117] By inputting the resistance parameter (R) of each zone and the measured surface temperature (T) and power parameter (P) of each zone, a mathematical model is finally established. The ultimate goal is to obtain the surface temperature of each zone by inputting variables according to the mathematical model.

[0118] Let the inner circle data be R0, P0, T0; and the outer circle data be R3, P3, T3.

[0119] Taking the inner circle data as an example, the collected three columns of data R0-P0-T0 are labeled, with the two columns of data R0-P0 labeled as input and the data T0 labeled as output. Through the system's identification method, the relationship between the input (R0-P0) and the output (T0) will be identified and represented as a mathematical model.

[0120] In one example, the mathematical model for the inner circle data is a form of ARMAX model. The mathematical model for the inner circle is shown by the following formula:

[0121]

[0122]

[0123]

[0124]

[0125]

[0126] The mathematical model for the outer ring is shown by the following formula:

[0127]

[0128]

[0129]

[0130]

[0131]

[0132] In the formula, and The output of the system is represented by the surface temperatures of the inner and outer rings, respectively, and t represents time. and These represent the input at the current moment, namely the resistance parameter and the power parameter; , , and All of these are the transfer polynomials of the input signals; and The polynomial describes the dynamic characteristics of the system, either inertia or delay; e(t) represents random noise. This indicates a time interval, representing the sampling interval. For example, a data sampling time of 1 second means that the data is from the previous second.

[0133] Please refer to Figure 10 , Figure 10 This is a comparison chart of the output temperature of the mathematical model in an embodiment of the present invention and the actual measured temperature.

[0134] like Figure 10 As shown, multiple models were set based on the collected data, and then the best-performing model was selected for temperature estimation. In this embodiment, the optimal model was a linear model. During the experiment, the optimal mathematical model was identified based on the relationship between (RP) and T. The blue line represents the calculated temperature output by inputting (RP) into the current mathematical model. The black line represents the actual temperature. The better the overlap between the black and blue lines, the more accurate the mathematical model.

[0135] After obtaining the model, it is converted into an algorithm. The resistance parameter R and power parameter P obtained in real time are used to calculate the temperature of each area of ​​the disk for real-time control, thereby determining whether to increase or decrease the power to achieve the control target value.

[0136] Existing methods for temperature estimation using lookup tables can cause a sudden drop in surface temperature if a wafer at room temperature is suddenly placed on the surface under normal temperature control. This results in a delay in the reflection of the temperature at the internal center measuring point and the resistance, leading to inaccurate control. However, this invention utilizes a system identification method to accurately establish the mathematical relationship between resistance parameters, preset temperature control parameters, and surface temperature. It also considers the influence of multiple input parameters on temperature, such as the wafer addition time and ambient temperature. By setting appropriate inputs according to requirements, accurate output can be obtained. Through experimental data-driven modeling, the dynamic characteristics of the actual system can be more accurately reflected, avoiding errors caused by traditional model assumptions and improving the accuracy and reliability of the mathematical model.

[0137] Please refer to Figures 7-8 , Figure 7 This is a flowchart illustrating the construction process of the resistance thermometer model according to an embodiment of the present invention.

[0138] In some embodiments, combined with Figure 7 and Figure 8 As shown, the steps for constructing the resistance thermometer model include:

[0139] Step S701: Obtain the mapping relationship between resistance parameters and surface temperature based on several sets of surface temperatures and the resistance parameters at each set of surface temperatures;

[0140] Step S702: Construct a resistance thermometer model based on the mapping relationship.

[0141] Please refer to Figure 11 , Figure 11 This is a schematic diagram of the temperature calculated based on resistance and the actual measured temperature according to an embodiment of the present invention.

[0142] like Figure 11 As shown, an experiment was conducted, using a resistance thermometer model to calculate the temperature based on resistance and the actual measured temperature, generating a model as follows: Figure 11 The temperature data graph shown shows good consistency between the calculated temperature and the real-time measured temperature.

[0143] Specifically, the resistance thermometer model is constructed based on the mapping relationship between resistance parameters and surface temperature. Since the thermistor heating element is set inside the target heating zone, compared with the prior art which uses the thermistor heating element itself as the model, the actual temperature obtained is the temperature inside the heating plate. The embodiments of the present invention can obtain the surface temperature based on the resistance parameters, and can accurately measure the surface temperature.

[0144] In some embodiments, step S502, according to a preset standard, selects to obtain the real-time temperature of the target heating zone based on resistance parameters and a pre-built resistance thermometer model, or obtains the real-time temperature based on resistance parameters, preset temperature control parameters, and a pre-built mathematical model, including:

[0145] Step S5021: Obtain the temperature control mode of the heating plate;

[0146] Step S5022: When the temperature control mode is constant temperature control, select the real-time temperature of the target heating zone based on the resistance parameters and the pre-built resistance temperature table model.

[0147] Step S5023: When the temperature control mode is heating control, the real-time temperature is obtained based on the resistance parameters, preset temperature control parameters and pre-built mathematical model.

[0148] Specifically, in constant temperature control, using a resistance thermometer model is simple and convenient. For example, if a stable operation at 100℃ is required, a lookup table method can meet the accuracy requirements.

[0149] When heating, such as from 100℃ to 200℃, using a lookup table to calculate the temperature at a specific point during the heating process will result in a lag, and the lookup table method cannot achieve very high precision, especially with very low resolution. In such cases, a mathematical model is more suitable for calculating the temperature. Mathematical models have the advantage of predicting temperature change trends in advance.

[0150] In some non-limiting embodiments, the temperature control method provided in the first aspect of the present invention can be implemented based on the heating plate temperature control system provided in the second aspect of the present invention. Specifically, the heating plate temperature control system is equipped with a memory and a processor. The memory includes, but is not limited to, the computer-readable storage medium provided in the third aspect of the present invention, on which computer instructions are stored. The processor is connected to the memory and is configured to execute the computer instructions stored in the memory to implement the temperature control method provided in the first aspect of the present invention.

[0151] In some embodiments of the present invention, the heating plate temperature control system may include a thermocouple, a voltage and current sampling circuit, and a controller.

[0152] The thermocouple, which can be made of nickel-chromium alloy, is located in the central area of ​​the heating plate. The voltage and current sampling circuit is connected to the heating wire in the heating plate to measure its resistance. The controller is configured to execute the temperature control method provided in the first aspect of this invention. Through this heating plate temperature control system and method, this application effectively avoids the thermal stress risks associated with a single heating mode by selecting the corresponding control mode according to different operating conditions of the equipment. This significantly improves the operational stability of the heating plate, reduces the probability of accidents such as breakage, and provides reliable assurance for the continuity and safety of the precision manufacturing process, thus possessing significant practical application value.

[0153] Please refer to the details. Figure 12 , Figure 12 A schematic flowchart of a temperature control method according to some embodiments of the present invention is shown.

[0154] like Figure 12 As shown, the controller of the heating plate temperature control system can first execute step S801: obtain the operating status of the semiconductor processing equipment.

[0155] Subsequently, the controller can execute step S802: in response to the operating condition indicating that the semiconductor processing equipment has not been calibrated for the heating wire resistance-temperature curve, it adopts a first control mode and measures the temperature of the heating plate via a thermocouple located in the central area of ​​the heating plate of the semiconductor processing equipment, so as to control the temperature of the heating plate and calibrate the heating wire resistance-temperature curve.

[0156] Specifically, the controller can first execute step S8021: obtain the highest target temperature of the heating plate, the preset temperature rise step size, and the preset constant temperature interval. Here, the temperature rise step size can be between 50℃ and 100℃, and the constant temperature interval can be between 5 minutes and 10 minutes.

[0157] Then, the controller can execute step S8022: gradually increase the first power supplied to the first heating wire located in the central area, and collect the first temperature of the central area at different times, so as to control the central area to be kept constant for one constant temperature interval for each temperature rise step below the highest target temperature.

[0158] Specifically, the initial power supplied to the first heating wire located in the central region can be increased from 0 or from any power value to improve regulation efficiency.

[0159] Then, the controller can execute step S8023: collect the first voltage and first current of the first heating wire at each constant temperature interval to calculate its first resistance value.

[0160] Specifically, a first sampling resistor is provided at the far end of the first heating wire connected to its driver, and the resistance value of the first sampling resistor is much smaller than the first resistance value of the first heating wire. The steps of collecting the first voltage and first current of the first heating wire at each constant temperature interval include: collecting the voltage across the first heating wire as the first voltage; and collecting the voltage across the first sampling resistor and dividing it by its resistance value to calculate the first current.

[0161] like Figure 8 As shown, the voltage parameter can be the first voltage mentioned above, and the current parameter can be the first current mentioned above. The purpose of calibrating the voltage and current parameters is to accurately calibrate the output voltage and current of the driver so as to ensure accurate calculation of subsequent temperature control. After clicking the automatic calibration voltage and current button on the host computer, the controller sends a command to the driver. The driver will slowly increase the current and voltage from zero to their maximum values, and at the same time, the driver will synchronously send the current channel ADC data, all voltage channel ADC data, and actual measurement data to the host computer. The host computer will record the current data. After the host computer finishes recording, the driver automatically shuts off the output, establishes the relationship between the voltage and current and the actual control signal, and writes this relationship into the driver. At this point, the automatic calibration is complete.

[0162] Finally, the controller can execute step S8024: calibrate the first resistance-temperature mapping curve based on the first resistance value and first temperature of the first heating wire at each constant temperature interval.

[0163] In addition, a second heating wire is provided in the edge area of ​​the heating plate, and the controller can further execute step S8025: according to a preset control ratio, provide a second power to the second heating wire provided in the edge area of ​​the heating plate synchronously (e.g., synchronously increase, synchronously keep constant) with the first power.

[0164] Specifically, the control ratio can be between (0.8 and 1). Preferably, the control ratio can be 0.9. Here, when using the control ratio mode, as the temperature increases, the temperature difference between the outer and inner rings increases. Therefore, this ratio ensures that the second temperature in the edge region is always slightly lower than the first temperature in the center region, preventing the heating plate from breaking. Those skilled in the art can calibrate the ratio range of the second power in the edge region to the first power in the center region at various temperatures based on the critical temperature difference between the inner and outer rings of the heating plate, and then take the median value of this ratio range as the preset ratio for synchronously controlling the second power.

[0165] Afterwards, the controller can also execute step S8026: collect the second voltage and second current of the second heating wire at the end of each constant temperature interval to calculate its second resistance value.

[0166] Specifically, a second sampling resistor is provided at the distal end of the second heating wire connected to its driver. The resistance value of the second sampling resistor is much smaller than the second resistance value of the second heating wire. The steps of acquiring the second voltage and second current of the second heating wire at the end of each constant temperature interval include: acquiring the voltage across the second heating wire as the second voltage; and acquiring the voltage across the second sampling resistor and dividing it by its resistance value to calculate the second current.

[0167] The controller can also perform step S8027: calibrate the second resistance-temperature mapping curve of the second heating wire based on the second resistance value of the second heating wire at the end of each constant temperature interval and the first temperature at the corresponding constant temperature interval.

[0168] In some embodiments of the present invention, the controller can, in response to the first temperature of the target heating zone surface reaching a maximum target temperature, gradually reduce the first power supplied to the first heating wire and control the target heating zone surface to be kept at a constant temperature for one constant temperature interval after each temperature rise step of temperature decrease. Here, the target heating zone can be the central region of the heating plate. The step of acquiring the first voltage and first current of the first heating wire at each constant temperature interval to calculate its first resistance value includes: calculating the average of the first resistance value obtained during the heating process and the first resistance value obtained during the cooling process, as the first resistance value of the first heating wire at each constant temperature interval. Thus, during the heating process, the temperature of the target heating zone surface is lower than the temperature of the first heating wire, and during the cooling process, the temperature of the target heating zone surface is higher than the temperature of the first heating wire. By calculating the average resistance of the first heating wire during the heating and cooling processes respectively, the present invention can effectively offset the calibration error caused by the temperature transfer delay from the first heating wire to the target heating zone surface.

[0169] In some embodiments of the present invention, the controller may, in response to the first power supplied to the first heating wire returning to zero, gradually increase the first power supplied to the first heating wire again, and control the surface of the target heating zone to remain constant for one constant temperature interval after each temperature increase step; and in response to the first temperature of the target heating zone surface reaching the highest target temperature again, gradually decrease the first power supplied to the first heating wire again, and control the surface of the target heating zone to remain constant for one constant temperature interval after each temperature decrease step. The step of acquiring the first voltage and first current of the first heating wire at each constant temperature interval to calculate its first resistance value includes: calculating the average of the first resistance values ​​obtained in each heating process and each cooling process, as the first resistance value of the first heating wire at each constant temperature interval. Thus, the present invention can eliminate random errors through multiple measurements and calculations.

[0170] In some embodiments of the present invention, the target heating area is the central region of the heating plate, and a second heating wire is also provided in the edge region of the heating plate. The controller can also place a temperature-sensing wafer on the heating plate. Here, multiple thermocouples are provided in the edge region of the temperature-sensing wafer. Then, according to a preset ratio, a second power is provided to the second heating wire synchronously with the first power, wherein the preset ratio is less than 1. Then, the second temperature of the edge region surface at each constant temperature interval is collected via the temperature-sensing wafer. Then, the second voltage and second current of the second heating wire at each constant temperature interval are collected to calculate its second resistance value. Finally, based on the second resistance value and second temperature of the second heating wire at each constant temperature interval, the second resistance-temperature mapping curve of the second heating wire is calibrated. Thus, by using a temperature-sensing wafer to more efficiently measure the temperature of the edge region surface of the heating plate, the calibration efficiency is improved.

[0171] Here, the first resistance-temperature mapping curve is represented as:

[0172]

[0173] in, The first temperature of the first heating wire. The first resistance value of the first heating wire. , and The fitting coefficients for the first resistance-temperature mapping curve, and / or

[0174] The second resistance-temperature mapping curve is represented as follows:

[0175]

[0176] in, The second temperature is the second temperature of the second heating wire. This is the second resistance value of the second heating wire. , and The fitting coefficients are those for the second resistance-temperature mapping curve.

[0177] Finally, the controller can execute step S803: in response to the operating status indication that the semiconductor processing equipment has been calibrated by the heating wire resistance-temperature curve, adopt the second control mode, measure the resistance of the heating wire in the heating plate, and combine the heating wire resistance-temperature curve to measure the temperature of the heating plate and control the temperature.

[0178] Specifically, the controller can first execute step S8031: measuring the first resistance of the first heating wire. Then, the controller can execute step S8032: determining the first temperature of the central region based on the first resistance and the first resistance-temperature mapping curve. The controller can then execute step S8033: determining the first power output to the first heating wire based on the difference between the first temperature and the first target temperature of the central region.

[0179] Then, the controller can execute either step S8032 or step S8033. Specifically, step S8032: In response to the operating status indicating that the current heating is based on the second control mode, the first sub-control mode is adopted, and the second power supplied to the second heating wire located in the edge area of ​​the heating plate is determined according to the first power and the preset control ratio. Here, the control ratio is (0.8, 1). Step S8033: In response to the operating status indicating that the current heating is not based on the second control mode, the second sub-control mode is adopted, the second resistance of the second heating wire is measured, and the second temperature of the edge area is determined by combining the corresponding second resistance-temperature mapping curve; and the second power output to the second heating wire is determined according to the difference between the second temperature and the second target temperature of the edge area.

[0180] Therefore, by executing step S8032 or step S8033, the controller enables the second control mode to switch between the first sub-control mode and the second sub-control mode.

[0181] Finally, the controller can also execute step S8034: in the second sub-control mode, determine whether the difference between the second temperature and the first temperature is within a preset temperature difference threshold, for example: -15℃~5℃; in response to the difference exceeding the temperature difference threshold, switch back to the first sub-control mode and re-determine the second power supplied to the second heating wire according to the first power and the preset control ratio.

[0182] Furthermore, in some embodiments of the present invention, in order to avoid temperature control failure caused by a single control mode malfunction, the present invention constructs an anomaly judgment mechanism while meeting the process temperature requirements under various operating conditions, thereby achieving precise monitoring and dynamic adjustment of parameters such as heating plate temperature, slope, and current.

[0183] In some embodiments, the temperature control method can measure the temperature of the heating plate and its rate of change, as well as the output power to the heating wire in the heating plate, in a second control mode to determine whether the second control mode is abnormal. Then, in response to the determination that the second control mode is abnormal, the method switches to a first control mode, where temperature is measured via thermocouples to control the temperature of the heating plate.

[0184] Accordingly, after calibrating the heating wire resistance-temperature curve, the temperature control method also measures the heating plate temperature and its slope of change in the first control mode, as well as the output power to the heating wire in the heating plate, to determine whether the first control mode is abnormal. Then, in response to the determination that the first control mode is abnormal, it switches to the second control mode, and uses the resistance of the heating wire and the heating wire resistance-temperature curve to measure and control the temperature of the heating plate.

[0185] Furthermore, the present invention also includes a monitoring device for the temperature of the heating plate, comprising a first voltage and current sampling circuit, a second voltage and current sampling circuit, and a controller.

[0186] The first voltage and current sampling circuit is connected to the first heating wire located in the center area of ​​the heating plate. The second voltage and current sampling circuit is connected to the second heating wire located in the edge area of ​​the heating plate. This heating plate temperature monitoring device can perform heating plate temperature monitoring methods, thereby avoiding the need for additional thermocouples. It can determine the temperature data of the center area and the edge area in real time and accurately, thus avoiding the risk of heating plate breakage due to abnormal local parameters or excessive temperature difference, and significantly improving the operating stability and service life of the heating plate under high temperature conditions.

[0187] Please refer to Figure 13 , Figure 13 A flowchart illustrating a method for monitoring the temperature of a heating plate according to some embodiments of the present invention is shown.

[0188] like Figure 13 As shown, the controller of the heating plate temperature monitoring device can first execute step S901: at multiple times, acquire the first voltage and first current at both ends of the first heating wire located in the central region of the heating plate, and the second voltage and second current at both ends of the second heating wire located in the edge region of the heating plate.

[0189] Then, the controller can execute step S902: using a pre-trained abnormal alarm model, perform temperature anomaly analysis on the first voltage, first current, second voltage and second current at multiple times to determine whether to output an alarm signal.

[0190] Specifically, the controller can execute step S9021: Based on the first voltage and first current at multiple moments, determine the first resistance of the first heating wire at each moment, and combine this with a pre-calibrated first resistance-temperature mapping curve to determine the first temperature of the central region at each moment; based on the second voltage and second current at multiple moments, determine the second resistance of the second heating wire at each moment, and combine this with a pre-calibrated second resistance-temperature mapping curve to determine the second temperature of the edge region at each moment; calculate the difference between the first and second temperatures at each moment, and compare it with a preset inner and outer ring temperature difference threshold to determine whether to output a first alarm signal indicating that the inner and outer ring temperature difference is too large. Here, the inner and outer ring temperature difference threshold can be between -5℃ and 15℃.

[0191] Subsequently, the controller can execute step S9022: comparing the first temperature of the central region at each time moment and the second temperature of the edge region at each time moment with preset temperature thresholds (e.g., 600℃~800℃) to determine whether to output a second alarm signal indicating that the temperature of the central region is too high and / or a second alarm signal indicating that the temperature of the edge region is too high. In some embodiments, based on the first temperature of the central region at each time moment, a first temperature change rate is determined, and the first temperature change rate is compared with preset change rate thresholds (e.g., 5℃ / min~10℃ / min and -5℃ / min~-10℃ / min) to determine whether to output a third alarm signal indicating that the temperature change rate of the central region is too high.

[0192] Here, the controller can also collect the third temperature of the central area at each time through thermocouples located in the central area of ​​the heating plate; and perform redundant temperature anomaly analysis on the third temperature through an anomaly alarm model to determine whether to output a second alarm signal indicating that the temperature of the central area is too high and / or a third alarm signal indicating that the temperature change rate of the central area is too large.

[0193] In some embodiments, a second temperature change rate is determined based on the second temperature of the edge region at each time point, and the second temperature change rate is compared with a preset change rate threshold to determine whether to output a fourth alarm signal indicating that the temperature change rate of the edge region is too large.

[0194] In some embodiments, the first current and the second current at each time are compared with preset current thresholds (e.g., 15A~25A) to determine whether to output a fifth alarm signal indicating that the current in the central region is too large and / or a sixth alarm signal indicating that the current in the edge region is too large.

[0195] Those skilled in the art will understand that the controller can perform the above-mentioned temperature anomaly analyses individually or synchronously, as well as output the corresponding first to sixth alarm signals, in order to improve the sensitivity and accuracy of temperature anomaly judgment.

[0196] Furthermore, the temperature difference threshold between the inner and outer rings, the temperature threshold, the rate of change threshold, and / or the current threshold are dynamically determined by the abnormal alarm model based on historical data.

[0197] Please refer to Figure 14 , Figure 14 A flowchart illustrating the training process of an anomaly alarm model according to some embodiments of the present invention is shown.

[0198] like Figure 14As shown, during the training of the abnormal alarm model, the controller can first execute step S1001: acquire historical temperature data under normal operating conditions of the heating plate, as well as historical abnormal threshold data of the heating plate when abnormal occurs, in order to construct a training sample set. The historical temperature data is the first temperature curve with respect to time, and the historical abnormal threshold data includes historical inner and outer ring temperature difference threshold, historical temperature threshold, historical rate of change threshold, and historical current threshold.

[0199] Then, the controller can execute step S1002: construct the abnormal alarm model to be trained, and input the historical temperature data from the training sample set into the abnormal alarm model one by one to obtain the abnormal threshold prediction value of its output.

[0200] Here, the predicted anomaly thresholds include predicted thresholds for the temperature difference between the inner and outer rings, the temperature threshold, the rate of change threshold, and the current threshold. The steps for constructing the anomaly alarm model to be trained may include: using a time series analysis algorithm (e.g., the ARIMA model) module and a machine learning regression algorithm (e.g., a random forest) module to construct the anomaly alarm model.

[0201] Optionally, the training sample set can be preprocessed beforehand. For example, outliers can be removed from the historical temperature data and historical outlier threshold data in the training sample set. Alternatively, the historical temperature data and historical outlier threshold data in the training sample set can be augmented. Another example is the standardization of the historical temperature data and historical outlier threshold data in the training sample set using Min-Max standardization or Z-Score standardization methods.

[0202] Finally, the controller can execute step S1003: determine the first loss function value of the anomaly alarm model based on the difference between each anomaly threshold prediction value and its corresponding historical anomaly threshold data, and correct the learning parameters of the anomaly alarm model accordingly until the first loss function value is less than the preset loss threshold.

[0203] Furthermore, training the anomaly alarm model also includes real-time data feedback and updating the model's learning parameters.

[0204] Specifically, the controller can first count the number of temperature adjustments performed on the heating plate. This temperature adjustment includes heating and / or cooling. Then, in response to completing a preset number of temperature adjustments (e.g., 100 times), the temperature data and abnormal threshold data involved in each adjustment are added to the training sample set. The abnormal threshold data is determined based on positive human feedback received for each alarm signal (e.g., shutting down the heating plate). Next, the temperature data added to the training sample set is input one by one into the abnormal alarm model to obtain its output abnormal threshold prediction value. Finally, based on the difference between each abnormal threshold prediction value and the corresponding abnormal threshold data added to the training sample set, the second loss function value of the abnormal alarm model is determined, and the learning parameters of the abnormal alarm are adjusted accordingly until the second loss function value is less than a preset loss threshold.

[0205] For example, if the difference between the predicted anomaly threshold and the corresponding anomaly threshold data added to the training sample set exceeds 5% for three consecutive times, the model parameters will be updated.

[0206] Furthermore, this application also fully utilizes the advantages of both models by selecting the corresponding model for temperature calculation in different scenarios.

[0207] Please refer to Figure 9 , Figure 9 This is a flowchart of another method for temperature control of a wafer heating plate according to an embodiment of the present invention.

[0208] The following combination Figure 9 The overall temperature control process of this application is explained.

[0209] 1. The driver is connected to the heating plate, and the voltage and current are automatically calibrated.

[0210] 2. The heating plate is subjected to a constant rate heating experiment. Data is collected at 10 Hz, including voltage and current. The resistance is calculated in real time according to Ohm's law. At the same time, the voltage, current, resistance, power, temperature of each zone of the heating plate, and ambient temperature are recorded in the data table.

[0211] 3. Systematically identify the resistance, power, surface temperature of each zone of the heating plate, and ambient temperature in the data table.

[0212] 4. Identify the relationship between input resistance, power, ambient temperature and the surface temperature output of each zone of the heating plate, such as a linear relationship, select the optimal relationship, and establish a mathematical model.

[0213] 5. At the same time, a resistance temperature meter model is also established based on the collected data. The resistance temperature meter model is switched to be used as needed according to the actual situation. The temperature calculated based on the model can also be used as a reference value.

[0214] 6. Convert the obtained mathematical model into a corresponding control algorithm, and use the algorithm to calculate the temperature of the heating plate in that area based on the real-time collected resistance, power, and ambient temperature (T1).

[0215] 7. Based on the preset standards and the actual heating plate conditions, switch between the mathematical model or the resistance thermometer model to calculate the temperature. You can use a single method or a combination of both methods for reference and temperature control.

[0216] 8. Based on the temperature calculated for that zone of the heating plate, perform PID control to control the temperature of each zone of the heating plate to rise at the set rate / set power until the specified target value is reached.

[0217] The temperature control algorithm mainly functions to reflect the temperature of each zone by calculating the real-time resistance based on the real-time voltage and current, and to control the temperature of each zone in real time so that the temperature reaches the target value. The purpose of calibrating the voltage and current parameters is to accurately calibrate the output voltage and current of the driver so that the subsequent temperature control can be calculated accurately.

[0218] Please refer to Figures 15-16 , Figure 15 This is a schematic diagram of the hardware connection when calibrating the output voltage and current of the driver according to an embodiment of the present invention. Figure 16 This is a flowchart illustrating the calibration of the driver output voltage and current according to an embodiment of the present invention.

[0219] When calibrating voltage and current, the driver output needs to be calibrated first. Figure 15 This diagram illustrates the hardware connections for calibrating the driver's output voltage and current. A high-precision voltmeter and a high-precision ammeter are used to measure the voltage and current from the driver output to the rated resistor, respectively. Figure 16 As shown, the driver, host computer, rated resistor, high-precision voltmeter, and high-precision ammeter are connected respectively. The host computer sends a command to start calibrating the voltage and current to the driver. The driver outputs power from 0W for 2 minutes. During this time, the host computer reads the data from the high-precision voltmeter and ammeter, as well as the original values ​​of the voltage and current channels actually acquired by the driver's ADC. The driver increases the output by 100W each time, until it reaches 3kW, with each constant power output lasting 2 minutes. The host computer reads the data from the high-precision voltmeter and ammeter, as well as the original values ​​of the voltage and current channels actually acquired by the driver's ADC for each constant power interval. After the acquisition is completed, the read values ​​and actual values ​​are calculated and a mapping relationship is established. The calculation results are stored in the corresponding driver, completing the driver output voltage and current calibration.

[0220] Please refer to Figures 17-18 , Figure 17 This is a schematic diagram of the hardware connection of the thermocouple sensor in the calibration process according to an embodiment of the present invention. Figure 18This is a flowchart of the calibration of the thermocouple sensor and the voltage acquisition process according to an embodiment of the present invention.

[0221] Thermistor heating elements actually use thermocouple sensors, such as... Figure 17 and Figure 18 As shown, thermocouple sensors generate different voltages (mV values) at different temperatures, so the temperature acquisition module is calibrated using mV values. Calculations are performed based on the different mV values ​​acquired by the ADC and the set value, thereby calibrating the acquired values ​​against the set value to make the calculated temperature more accurate.

[0222] First, during the calibration process, the host computer software can directly connect to the driver via the communication interface. A temperature acquisition module calibration command is sent to the driver. At this time, the driver enters the calibration mode and sends an output voltage command to the signal generator, with the output ranging from 0mV to 55mV, increasing by 5mV each time. For each constant voltage output interval, the actual ADC acquisition value within that 5-minute period is recorded and averaged. The set output value is also recorded. This continues until the maximum set mV value is reached. Finally, the actual acquisition value and the set value for each interval are linearly interpolated to obtain the optimal acquisition result. The mathematical correspondence is written into the driver's memory, thus completing the driver's temperature acquisition module calibration. The accurate temperature can then be calculated from the mV value generated by the TC thermocouple sensor.

[0223] This invention improves the accuracy and real-time performance of temperature control by combining mathematical models or resistance thermometer models for model optimization and selection, enabling real-time temperature control and feedback. These innovations make this solution highly reliable and efficient in practical applications.

[0224] Please refer to Figure 19 , Figure 19 This is a structural block diagram of the temperature control device for the wafer heating plate according to an embodiment of the present invention.

[0225] This invention also provides a temperature control device for a wafer heating plate, such as... Figure 19 As shown, it includes:

[0226] The parameter acquisition module 1301 is used to acquire preset temperature control parameters and resistance parameters of the thermistor heating element set inside the target heating zone in the heating plate.

[0227] The real-time temperature acquisition module 1302 is used to select, according to preset standards, to acquire the real-time temperature of the target heating zone based on resistance parameters and a pre-built resistance temperature meter model, or to acquire the real-time temperature based on resistance parameters, preset temperature control parameters and a pre-built mathematical model. The input of the mathematical model is resistance parameters and preset temperature control parameters, and the output is the real-time temperature. The mathematical model is constructed by using a system identification method.

[0228] The heating power adjustment module 1303 is used to adjust the heating power of the target heating zone according to the real-time temperature so that the real-time temperature reaches the target temperature.

[0229] The temperature control device for the wafer heating plate of this invention obtains preset temperature control parameters and the resistance parameters of the thermistor heating element located inside the target heating area in the heating plate. According to preset standards, it selects to obtain the real-time temperature of the target heating area based on the resistance parameters and a pre-built resistance temperature table model, or based on the resistance parameters, preset temperature control parameters, and a pre-built mathematical model. The mathematical model is input to the resistance parameters and preset temperature control parameters, and outputs the real-time temperature. The mathematical model is constructed using a system identification method, which can obtain accurate real-time temperature. Then, the heating power of the target heating area is adjusted according to the real-time temperature to make the real-time temperature reach the target temperature. By selecting two models to obtain the real-time temperature according to the actual situation, it can adapt to complex temperature changes and thus improve control accuracy.

[0230] Furthermore, the temperature control device for the wafer heating plate also includes:

[0231] The group parameter acquisition module is used to acquire several groups of surface temperatures of the target heating zone, as well as the resistance parameters and preset temperature control parameters of each group of surface temperatures;

[0232] The system identification module is used to systematically identify the resistance parameters, preset temperature control parameters and surface temperature, and obtain the target mathematical relationship between the resistance parameters and preset temperature control parameters of the target heating zone and the surface temperature.

[0233] The mathematical model building module is used to build mathematical models based on target mathematical relationships.

[0234] Furthermore, the group parameter acquisition module includes:

[0235] The parameter calibration module is used to calibrate the voltage and current parameters collected from the target heating zone;

[0236] The heating control module is used to control the heating plate to heat up at a constant rate and to collect the surface temperature of the target heating area at different times.

[0237] The data acquisition module is used to collect the voltage parameters, current parameters, and preset temperature control parameters of the target heating zone after calibration at different surface temperatures;

[0238] The resistance calculation module is used to calculate resistance parameters based on voltage and current parameters.

[0239] Furthermore, the system identification module includes:

[0240] The mathematical relationship acquisition module is used to identify the resistance parameters, preset temperature control parameters and surface temperature, and obtain several initial mathematical relationships between the resistance parameters and preset temperature control parameters of the target heating area and the surface temperature.

[0241] The optimal model verification module is used to verify the prediction error of the initial mathematical relation and take the initial mathematical relation with the smallest prediction error as the target mathematical relation.

[0242] Furthermore, the mathematical model adopts a multi-input single-output model, and the preset temperature control parameters include power parameters.

[0243] Furthermore, the preset temperature control parameters also include ambient temperature.

[0244] Furthermore, the temperature control device for the wafer heating plate also includes:

[0245] The mapping relationship acquisition module is used to obtain the mapping relationship between resistance parameters and surface temperature based on several sets of surface temperatures and the resistance parameters at each set of surface temperatures.

[0246] The table model acquisition module is used to construct a resistance temperature table model based on the mapping relationship.

[0247] Furthermore, the real-time temperature acquisition module includes:

[0248] Temperature control mode acquisition module, used to acquire the temperature control mode of the heating plate;

[0249] The first selection module is used to select the real-time temperature of the target heating zone based on the resistance parameters and a pre-built resistance temperature table model when the temperature control mode is constant temperature control.

[0250] The second selection module is used to obtain the real-time temperature based on the resistance parameters, preset temperature control parameters, and a pre-built mathematical model when the temperature control mode is heating control.

[0251] Please refer to Figure 20 , Figure 20 This is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention.

[0252] This invention also provides a schematic diagram of the structure of a computer device, such as... Figure 20As shown, the computer device includes one or more processors 10, memory 20, and interfaces for connecting the components, including high-speed interfaces and low-speed interfaces. The components communicate with each other via different buses and can be mounted on a common motherboard or otherwise installed as needed. The processors can process instructions executed within the computer device, including instructions stored in or on memory to display graphical information of a GUI on external input / output devices (such as display devices coupled to the interfaces). In some alternative implementations, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple computer devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system). Figure 20 Take a processor 10 as an example.

[0253] Processor 10 may be a central processing unit, a network processor, or a combination thereof. Processor 10 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GDA), or any combination thereof.

[0254] The memory 20 stores instructions executable by at least one processor 10 to cause at least one processor 10 to perform the method shown in the above embodiments.

[0255] The memory 20 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computer device. Furthermore, the memory 20 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, the memory 20 may optionally include memory remotely located relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0256] The memory 20 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory 20 may also include a combination of the above types of memory.

[0257] The computer device also includes an input device 30 and an output device 40. The processor 10, memory 20, input device 30, and output device 40 can be connected via a bus or other means. Figure 20 Taking the example of a connection between China and Israel via a bus.

[0258] Input device 30 can receive input numerical or character information, and generate key signal inputs related to user settings and function control of the computer device, such as a touchscreen, keypad, mouse, trackpad, touchpad, joystick, one or more mouse buttons, trackball, joystick, etc. Output device 40 may include display devices, auxiliary lighting devices (e.g., LEDs), and haptic feedback devices (e.g., vibration motors). The aforementioned display devices include, but are not limited to, liquid crystal displays, light-emitting diodes, displays, and plasma displays. In some alternative embodiments, the display device may be a touchscreen.

[0259] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods shown in the above embodiments.

[0260] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0261] In summary, the temperature control method, heating plate temperature control system, and computer-readable storage medium provided by this invention can be used to avoid the thermal stress risk caused by a single heating mode, thereby improving the operational stability of the heating plate and reducing the risk of fragmentation.

[0262] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and all such modifications and variations fall within the scope of protection.

Claims

1. A temperature control method, characterized in that, Includes the following steps: Obtain the operating status of semiconductor processing equipment; In response to the operating condition indicating that the semiconductor processing equipment has not been calibrated for the heating wire resistance-temperature profile, a first control mode is adopted, and temperature is measured via a thermocouple located in the central region of the heating plate of the semiconductor processing equipment, so as to perform temperature control and heating wire resistance-temperature profile calibration on the heating plate. as well as In response to the operating condition indicating that the semiconductor processing equipment has been calibrated by the heating wire resistance-temperature curve, a second control mode is adopted to measure the resistance of the heating wire in the heating plate and to perform temperature measurement and temperature control on the heating plate in combination with the heating wire resistance-temperature curve.

2. The temperature control method as described in claim 1, characterized in that, The step of measuring temperature via a thermocouple located in the central region of the heating plate of the semiconductor processing equipment to control the temperature of the heating plate and calibrate the heating wire resistance-temperature profile includes: The highest target temperature of the heating plate, the preset temperature rise step size, and the preset constant temperature interval are obtained. The first power supplied to the first heating wire located in the central region is gradually increased, and the first temperature of the central region at different times is collected to control the central region within the range below the highest target temperature. The temperature is kept constant for one temperature interval for each temperature rise step. The first voltage and first current of the first heating wire at each of the said constant temperature intervals are collected to calculate its first resistance value; and Based on the first resistance value and first temperature of the first heating wire at each of the constant temperature intervals, the first resistance-temperature mapping curve is calibrated.

3. The temperature control method as described in claim 2, characterized in that, The step of measuring temperature via a thermocouple located in the central region of the heating plate of the semiconductor processing equipment to control the temperature of the heating plate and calibrate the heating wire resistance-temperature curve further includes: According to a preset control ratio, a second power is provided synchronously to the second heating wire located in the edge area of ​​the heating plate, along with the first power, wherein the control ratio is (0.8, 1). The second voltage and second current of the second heating wire at each of the constant temperature intervals are collected to calculate its second resistance value; and Based on the second resistance value of the second heating wire at the end of each constant temperature interval and the first temperature at the corresponding constant temperature interval, the second resistance-temperature mapping curve of the second heating wire is calibrated.

4. The temperature control method as described in claim 2, characterized in that, The steps of using the second control mode to measure the resistance of the heating wire in the heating plate and to perform temperature measurement and temperature control of the heating plate based on the heating wire resistance-temperature curve include: Measure the first resistance of the first heating wire; Based on the first resistance and the first resistance-temperature mapping curve, determine the first temperature of the central region; and The first power output to the first heating wire is determined based on the difference between the first temperature and the first target temperature of the central region.

5. The temperature control method as described in claim 4, characterized in that, The step of using the second control mode to measure the resistance of the heating wire in the heating plate and using the heating wire resistance-temperature curve to measure and control the temperature of the heating plate further includes: In response to the operating condition status indicating that the current heating is the first heating based on the second control mode, a first sub-control mode is adopted, and a second power is determined to be provided to the second heating wire located in the edge area of ​​the heating plate according to the first power and a preset control ratio, wherein the control ratio is (0.8, 1).

6. The temperature control method as described in claim 5, characterized in that, The step of using the second control mode to measure the resistance of the heating wire in the heating plate and using the heating wire resistance-temperature curve to measure and control the temperature of the heating plate further includes: In response to the operating condition indicating that the current temperature rise is not based on the second control mode, a second sub-control mode is adopted, the second resistance of the second heating wire is measured, and the second temperature of the edge region is determined by combining the corresponding second resistance-temperature mapping curve; and The second power output to the second heating wire is determined based on the difference between the second temperature and the second target temperature of the edge region.

7. The temperature control method as described in claim 6, characterized in that, It also includes the following steps: In the second sub-control mode, it is determined whether the difference between the second temperature and the first temperature is within a preset temperature difference threshold. In response to the difference exceeding the temperature difference threshold, the system switches back to the first sub-control mode and re-determines the second power supplied to the second heating wire based on the first power and the preset control ratio.

8. The temperature control method as described in claim 1, characterized in that, It also includes the following steps: In the second control mode, the temperature of the heating plate and its rate of change, as well as the output power to the heating wire in the heating plate, are measured to determine whether the second control mode is in an abnormal state. as well as In response to the judgment result that the second control mode is abnormal, the system switches to the first control mode and measures the temperature of the heating plate via the thermocouple.

9. The temperature control method as described in claim 8, characterized in that, It also includes the following steps: After completing the calibration of the heating wire resistance-temperature curve, the temperature of the heating plate and its slope of change, as well as the output power to the heating wire in the heating plate, are measured under the first control mode to determine whether the first control mode is abnormal. as well as In response to the judgment result that the first control mode is abnormal, the system switches to the second control mode, and measures and controls the temperature of the heating plate by means of the resistance of the heating wire and the resistance-temperature curve of the heating wire.

10. A heating plate temperature control system, characterized in that, include: Thermocouple is located in the central area of ​​the heating plate; A voltage and current sampling circuit is connected to the heating wire in the heating plate to measure its resistance; as well as The controller is configured to perform the temperature control method as described in any one of claims 1 to 9.

11. A computer-readable storage medium storing computer instructions thereon, characterized in that, When the computer instructions are executed by the processor, the temperature control method as described in any one of claims 1 to 9 is implemented.

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