A method for temperature control of a heating plate, a heating plate, and a semiconductor device.

Abstract

This application provides a temperature control method for a heating plate, a heating plate, and a semiconductor device. The heating plate includes multiple temperature-adjustable zones, each including a metal circuit. The method includes: sampling the temperature of each temperature-adjustable zone multiple times during multiple first fixed time periods in the process, and sampling the temperature of each temperature-adjustable zone again during a second fixed time period after the process ends, obtaining multiple sampled temperature values ​​for each temperature-adjustable zone. The sampled temperature values ​​and set temperature values ​​are calculated and analyzed to obtain a corrected temperature value for each temperature-adjustable zone. The correspondence between the corrected temperature value of each temperature-adjustable zone and the current value of the metal circuit when the corrected temperature value is applied is obtained. This allows control of the actual temperature value of each temperature-adjustable zone based on the correspondence and the current value of the metal circuit when the corrected temperature value is applied. The actual temperature value obtained after applying the corrected temperature value approaches the set temperature value, achieving accurate temperature control of each temperature-adjustable zone of the heating plate.

Description

Technical Field

[0001] This invention relates to the field of semiconductors, and in particular to a method for temperature control of a heating plate, a heating plate, and a semiconductor device. Background Technology

[0002] With the development of semiconductor-related technologies, the manufacturing processes of semiconductor devices and chips are also developing rapidly.

[0003] In the manufacturing process of semiconductor devices, heating plates are typically used. The device to be manufactured is placed on the heating plate, and the heating plate heats the device to improve its performance.

[0004] However, the current heating plate suffers from inaccurate temperature control. Summary of the Invention

[0005] In view of this, the purpose of this application is to provide a temperature control method for a heating plate, a heating plate, and a semiconductor device, which can improve the accuracy of temperature control of the heating plate.

[0006] This application provides a temperature control method for a heating plate, the heating plate comprising multiple temperature-adjusting zones, each temperature-adjusting zone including a metal circuit; the method includes:

[0007] Multiple temperature samples are taken for each temperature-controlled region during multiple first fixed time periods in the process, and temperature samples are taken for each temperature-controlled region during a second fixed time period after the process is completed, to obtain multiple sampled temperature values ​​for each temperature-controlled region.

[0008] The sampled temperature value and the set temperature value are calculated and analyzed to obtain the corrected temperature value for each temperature control zone. The set temperature value is a preset temperature value for each temperature control zone.

[0009] Obtain the correspondence between the corrected temperature value of each temperature-adjusting zone and the current value of the metal circuit when the corrected temperature value is applied;

[0010] The actual temperature value of each temperature-adjusting zone is controlled according to the correspondence and the current value of the metal circuit when the corrected temperature value is implemented, and the difference between the actual temperature value and the set temperature value is less than a first threshold.

[0011] Optionally, the correspondence between obtaining the corrected temperature value of each of the temperature-adjusting zones and the current value of the metal circuit when implementing the corrected temperature value includes:

[0012] Obtain a temperature-impedance curve between the corrected temperature value of each temperature-controlled zone and the impedance value of the metal circuit when the corrected temperature value is applied;

[0013] The calculation formulas for obtaining the impedance value of the metal circuit and the current value of the metal circuit when implementing the correction temperature value in each of the temperature control zones;

[0014] The corresponding relationship between the corrected temperature value of each temperature-adjustment zone and the current value of the metal circuit when the corrected temperature value is applied is obtained based on the temperature-impedance curve and the calculation formula.

[0015] Optionally, the method further includes:

[0016] The process conditions for a complete process are preset, including the process time period and the set temperature value for each temperature control zone;

[0017] The sampled temperature value includes a first temperature value and a second temperature value;

[0018] The process of sampling temperature multiple times for each temperature-controlled region during multiple first fixed time periods in the process, and sampling temperature for each temperature-controlled region during a second fixed time period after the process is completed, to obtain multiple sampled temperature values ​​for each temperature-controlled region, includes:

[0019] During the process, the set temperature value is applied to each of the temperature control zones during the process time period. Multiple first fixed time periods are set, and temperature sampling is performed multiple times for each of the temperature control zones during the multiple first fixed time periods to obtain multiple first temperature values ​​for each of the temperature control zones.

[0020] After the process time period ends, a second fixed time period is set, and temperature sampling is performed on each of the temperature-adjusting zones during the second fixed time period to obtain a second temperature value for each of the temperature-adjusting zones.

[0021] The step of controlling the actual temperature value of each temperature-adjusting zone based on the correspondence and the current value of the metal circuit when implementing the corrected temperature value includes:

[0022] Under the stated process conditions, the actual temperature value of each temperature-adjusting zone is controlled according to the corresponding relationship and the current value of the metal circuit when the corrected temperature value is implemented.

[0023] Optionally, the first fixed time period is the time period during which the electrostatic chuck power supply and the radio frequency power supply are turned off, and the second fixed time period is the time period after the electrostatic chuck power supply and the radio frequency power supply are turned off.

[0024] Optionally, the first fixed time period and the second fixed time period are less than or equal to 1 second.

[0025] Optionally, the actual temperature value and the set temperature value are equal.

[0026] Optionally, the method further includes:

[0027] The process conditions are repeated N times consecutively, and each temperature control region under the process conditions is sampled repeatedly N times, where N is a natural number greater than 2.

[0028] Optionally, the multiple temperature samplings performed on each of the temperature-controlled zones during multiple first fixed time periods in the process, and the temperature sampling performed on each of the temperature-controlled zones during a second fixed time period after the process is completed, to obtain multiple sampled temperature values ​​for each of the temperature-controlled zones, include:

[0029] During the process, the temperature of each temperature-controlled area is sampled M times during M first fixed time periods, and the temperature of each temperature-controlled area is sampled once during the second fixed time period after the process ends, so as to obtain M+1 sampled temperature values ​​for each temperature-controlled area, where M is a natural number greater than 50.

[0030] Optionally, the intervals between the multiple first fixed time periods are the same, and the interval between the last first fixed time period and the second fixed time period is the same as the interval between two adjacent first fixed time periods.

[0031] This application provides a heating plate, which includes multiple temperature-adjusting zones, each temperature-adjusting zone including a metal circuit, and the distance between the metal circuit and the heating surface of the heating plate is less than a second threshold.

[0032] The actual temperature value of the heating plate can be controlled using any of the methods described above.

[0033] Optionally, the range of the second threshold is 0.1 mm to 2 mm.

[0034] Optionally, the number of temperature-regulating zones is at least greater than 20.

[0035] This application provides a semiconductor device, characterized in that the semiconductor device includes an electrostatic chuck, a radio frequency generator, and the heating plate described above.

[0036] This application provides a temperature control method for a heating plate. The heating plate includes multiple temperature-adjustable zones, each containing a metal circuit. This means the temperature of the temperature-adjustable zone can be adjusted using the metal circuit. The method includes: sampling the temperature of each temperature-adjustable zone multiple times during multiple first fixed time periods in the process, and sampling the temperature of each temperature-adjustable zone again during a second fixed time period after the process ends, obtaining multiple sampled temperature values ​​for each temperature-adjustable zone. This provides the sampled temperature values ​​for each temperature-adjustable zone of the heating plate from the start to the end of the process. Then, the sampled temperature values ​​and set temperature values ​​are calculated and analyzed to obtain a corrected temperature value for each temperature-adjustable zone. The set temperature value is a pre-set temperature value for each temperature-adjustable zone; that is, to achieve the set temperature value, the temperature actually applied to the heating plate is the corrected temperature value. The correspondence between the calibrated temperature value and the current value of the metal circuit when the calibrated temperature value is applied is obtained for each temperature-controlled zone. This allows for control of the actual temperature value of each zone based on this correspondence and the current value of the metal circuit when the calibrated temperature value is applied. The difference between the actual temperature value and the set temperature value is less than a first threshold. In other words, the actual temperature value of each temperature-controlled zone within the heating plate can be controlled by setting the current value of the metal circuit when the calibrated temperature value is applied. The actual temperature value is obtained by applying the calibrated temperature value, and the actual temperature value obtained after applying the calibrated temperature value approaches the set temperature value, thereby achieving accurate temperature control of each temperature-controlled zone of the heating plate and improving the accuracy of temperature control. Furthermore, accurate temperature control of each temperature-controlled zone can achieve better process results and improve the uniformity of the coating. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 A schematic flowchart of a temperature control method for a heating plate provided in an embodiment of this application is shown;

[0039] Figure 2 The diagram shows a top view of a heating plate according to an embodiment of this application. Detailed Implementation

[0040] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0041] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0042] This application is described in detail with reference to the schematic diagrams. When detailing the embodiments of this application, for ease of explanation, the cross-sectional views illustrating the structure may be partially enlarged, not according to general proportions. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of this application. In actual manufacturing, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0043] With the development of semiconductor-related technologies, the manufacturing processes of semiconductor devices and chips are also developing rapidly.

[0044] In the manufacturing process of semiconductor devices, heating plates are commonly used. A heating plate includes heating circuitry. The device to be manufactured is placed on the heating plate, and the heating circuitry in the heating plate heats the device to improve its performance.

[0045] To improve the heating uniformity of a heating plate, it can be divided into multiple temperature-controlled zones, with each zone individually temperature-controlled. When using the heating plate, the temperature of each zone needs to be measured to determine the actual temperature of the heating plate. This can be achieved using a resistance temperature detector (RTD). An resistance temperature detector is a temperature measuring device that measures temperature by detecting the impedance of a metallic material. Once the power supply voltage of the heating plate is determined, if the voltage value Vm and the current value Ahn flowing through the heating circuit can be obtained, the impedance value Rn of the heating circuit can be deduced. Therefore, the actual temperature value Tn of the heating plate can be estimated using the impedance value Rn.

[0046] However, in actual manufacturing processes, the voltage of the heating plate is close to 1 kV, and the circuitry of the electrostatic chuck (ESC) and the radio frequency (RF) generator overlaps, which causes interference to the impedance temperature detector and makes temperature measurement difficult. Since the measured temperature value of the heating plate may be inaccurate, the temperature control of the heating plate will also be inaccurate.

[0047] Based on this, this application provides a temperature control method for a heating plate. The heating plate includes multiple temperature-adjustable zones, each including a metal circuit. This means the temperature of the temperature-adjustable zone can be adjusted using the metal circuit. The method includes: sampling the temperature of each temperature-adjustable zone multiple times during multiple first fixed time periods in the process, and sampling the temperature of each temperature-adjustable zone again during a second fixed time period after the process ends, obtaining multiple sampled temperature values ​​for each temperature-adjustable zone. This provides the sampled temperature values ​​for each temperature-adjustable zone of the heating plate from the start to the end of the process. Then, the sampled temperature values ​​and set temperature values ​​are calculated and analyzed to obtain a corrected temperature value for each temperature-adjustable zone. The set temperature value is a pre-set temperature value for each temperature-adjustable zone; that is, to achieve the set temperature value, the temperature actually applied to the heating plate is the corrected temperature value. The correspondence between the calibrated temperature value and the current value of the metal circuit when the calibrated temperature value is applied is obtained for each temperature-controlled zone. This allows for control of the actual temperature value of each zone based on this correspondence and the current value of the metal circuit when the calibrated temperature value is applied. The difference between the actual temperature value and the set temperature value is less than a first threshold. In other words, the actual temperature value of each temperature-controlled zone within the heating plate can be controlled by setting the current value of the metal circuit when the calibrated temperature value is applied. The actual temperature value is obtained by applying the calibrated temperature value, and the actual temperature value obtained after applying the calibrated temperature value approaches the set temperature value, thereby achieving accurate temperature control of each temperature-controlled zone of the heating plate and improving the accuracy of temperature control. Furthermore, accurate temperature control of each temperature-controlled zone can achieve better process results and improve the uniformity of the coating.

[0048] To better understand the technical solution and effects of this application, the specific embodiments will be described in detail below with reference to the accompanying drawings.

[0049] See Figure 1 The figure is a schematic flowchart of a temperature control method for a heating plate provided in an embodiment of this application.

[0050] The heating plate provided in this embodiment of the application refers to... Figure 2As shown, the system includes multiple temperature-regulating regions 110, and the area difference between these regions is less than a target threshold. The target threshold can be the actual area difference or a proportional relationship, such as a target percentage difference in area between the multiple temperature-regulating regions. The target percentage could be 5%. In other words, the areas of the multiple temperature-regulating regions 110 are approximately equal, meaning the temperature regulation layer 100 is divided into multiple temperature-regulating regions 110 with approximately equal areas. This allows for individual temperature regulation of a specific temperature-regulating region 110.

[0051] The number of temperature control zones 110 can be determined based on the precision of temperature adjustment and the area of ​​the heating plate. Specifically, the number of temperature control zones 110 can be at least greater than 20. The more temperature control zones 110 there are, the smaller the area of ​​each temperature control zone 110 will be for the same heating plate area, resulting in finer temperature adjustment and allowing for more precise temperature control of each area of ​​the heating plate. For example, the number of temperature control zones 110 could be 81.

[0052] Each temperature control zone 110 is provided with at least one metal circuit 111. The temperature of the temperature control zone 110 corresponding to the metal circuit 111 can be adjusted by using the metal circuit 111, thereby realizing temperature control of each temperature control zone 110 in the heating plate.

[0053] The temperature control method for the heating plate provided in this embodiment includes the following steps:

[0054] S101, the temperature of each temperature-controlled area is sampled multiple times during multiple first fixed time periods in the process, and the temperature of each temperature-controlled area is sampled again during a second fixed time period after the process is completed, so as to obtain multiple sampled temperature values ​​for each temperature-controlled area.

[0055] In the embodiments of this application, process conditions for a complete process can be preset, and then the process conditions can be executed. Under these process conditions, temperature samples can be taken multiple times for each temperature-controlled area. This process may not be the actual process, but a test process before the actual process.

[0056] Process conditions can include the process time period and the set temperature value for each temperature-controlled zone. The set temperature value for each temperature-controlled zone can be a pre-set temperature value for that zone, i.e., the desired temperature to which each zone is heated or the desired temperature to be reached. The process time period can be the duration for which each temperature-controlled zone maintains that set temperature value. Thus, pre-setting process conditions can mean pre-setting the process time period for each process and the set temperature value for each temperature-controlled zone.

[0057] As an example, the process conditions are preset to a set temperature of 500°C for each temperature-controlled zone, and the process time is 30 minutes (min), meaning that each temperature-controlled zone of the heating plate is maintained at 500°C for approximately 30 minutes.

[0058] When conducting each test process using the process conditions, multiple temperature samples can be taken for each temperature-controlled area during multiple first fixed time periods in the process, and temperature samples can also be taken for each temperature-controlled area during a second fixed time period after the process ends, so as to obtain the sampled temperature value of each temperature-controlled area.

[0059] The sampled temperature value may include a first temperature value and a second temperature value, wherein the first temperature value may be a temperature value sampled during the process, and the second temperature value may be a temperature value sampled after the process.

[0060] Specifically, during the testing process, a set temperature value is applied to each temperature-controlled zone during the process time period. Multiple first fixed time periods are set, and temperature samples are taken multiple times for each temperature-controlled zone during these first fixed time periods to obtain multiple first temperature values ​​for each temperature-controlled zone. After the process time period ends, a second fixed time period is set, and temperature samples are taken for each temperature-controlled zone during this second fixed time period to obtain a second temperature value for each temperature-controlled zone.

[0061] In the actual temperature sampling process, temperature sampling can be performed once for each temperature-controlled area during the second fixed time period and each first fixed time period, or multiple times for each temperature-controlled area.

[0062] As one possible implementation, M first fixed time periods can be set during the testing process, and the temperature of each temperature-controlled area can be sampled once during each of the M first fixed time periods, thereby achieving M temperature samplings for each temperature-controlled area during the M first fixed time periods.

[0063] During a fixed time period after the completion of the testing process, temperature samples are taken once for each temperature-controlled zone. This results in a total of M+1 sampled temperature values ​​for each temperature-controlled zone from the start to the end of the testing process, where M can be a natural number greater than 50. In other words, a large number of temperature samples are taken multiple times for each temperature-controlled zone to facilitate subsequent processing of the sampled temperature values. For example, 100 samples can be taken for each temperature-controlled zone, resulting in 100 sampled temperature values.

[0064] In practical applications, to increase the amount of temperature sampling data, the same process can be repeated continuously, that is, the test process can be repeated N times, the same process conditions can be repeated N times, and sampling can be performed on each temperature-controlled area under the same process conditions N times. Here, N can be a natural number greater than 2. For example, N can be 25, that is, the same process conditions can be repeated 25 times, the same process can be repeated 25 times, and sampling can be performed on each temperature-controlled area under the same process conditions in each of the 25 test processes.

[0065] In the embodiments of this application, during the testing process, both the electrostatic chuck power supply and the radio frequency (RF) power supply affect temperature sampling. To avoid the influence of the electrostatic chuck power supply and RF power supply on temperature sampling, the first fixed time period can be the period during which the electrostatic chuck power supply and RF power supply are turned off. That is, temperature sampling can be performed during the period when the electrostatic chuck power supply and RF power supply are turned off during the testing process. This allows for temperature sampling of each temperature-adjustable area, avoiding the influence of the electrostatic chuck power supply and RF power supply on temperature sampling. The first fixed time period is less than or equal to 1 second, meaning the period during which the electrostatic chuck power supply and RF power supply are turned off is less than or equal to 1 second. Within this 1 second, the temperature of the heating plate will not change significantly. Therefore, it is necessary to sample the temperature of each temperature-adjustable area within 1 second to obtain the first temperature value.

[0066] Specifically, a set temperature value can be applied to each temperature-controlled zone during the test process time period. The test process includes multiple periods when the electrostatic chuck power supply and RF power supply are turned off. Temperature sampling can be performed on each temperature-controlled zone during each period when the electrostatic chuck power supply and RF power supply are turned off to obtain multiple first temperature values ​​for each temperature-controlled zone.

[0067] As an example, a set temperature of 500℃ is applied to each temperature-controlled zone for approximately 30 minutes. During the test process, within one second of the electrostatic chuck power supply and RF power supply being turned off, the temperature of each temperature-controlled zone is sampled to obtain a first temperature value. Multiple one-second power-off periods for the electrostatic chuck power supply and RF power supply are set during the test process to achieve multiple temperature samples for each temperature-controlled zone, obtaining multiple first temperature values. After the test process ends, i.e., after the process time period ends, the electrostatic chuck power supply and RF power supply can be turned off. The second fixed time period can be the time period after the electrostatic chuck power supply and RF power supply are turned off. The second fixed time period is relatively short so that temperature sampling can be performed before the temperature value of each temperature-controlled zone of the heating plate changes. At this time, since the electrostatic chuck power supply and RF power supply have been turned off, the influence of the electrostatic chuck power supply and RF power supply on the temperature sampling can be avoided. The second fixed time can be less than or equal to one second.

[0068] Specifically, after the process time period of the test process ends, the temperature of each temperature-controlled area is sampled during the second fixed time period after the electrostatic chuck power supply and the radio frequency power supply are turned off, so as to obtain the second temperature value of each temperature-controlled area.

[0069] As an example, within 1 second after the electrostatic chuck power supply and RF power supply are turned off, the temperature of each temperature-controlled zone is sampled to obtain a second temperature value for each temperature-controlled zone.

[0070] Therefore, it can be seen that a large number of temperature samples can be taken from each temperature control zone during and after each test process, and the selected sampling time points can avoid the influence of electrostatic chuck power supply and RF power supply.

[0071] In the embodiments of this application, the intervals between multiple first fixed time periods are the same, and the interval between the last first fixed time period and the second fixed time period is the same as the interval between two adjacent first fixed time periods, thus achieving uniform sampling during the testing process.

[0072] S102 calculates and analyzes the sampled temperature value and the set temperature value to obtain the corrected temperature value for each temperature control zone.

[0073] In the embodiments of this application, after obtaining multiple sampled temperature values, the sampled temperature values ​​can be analyzed and temperature correction can be performed to obtain the corrected temperature value for each temperature adjustment zone.

[0074] Specifically, the sampled temperature value and the set temperature value can be calculated and analyzed to obtain the corrected temperature value for each temperature control zone.

[0075] By calculating and analyzing the set temperature value and the sampled temperature values, a corrected temperature value is obtained. The corrected temperature value is the temperature value that needs to be implemented after adjustment; that is, the corrected temperature value is the actual temperature value that should be applied. After the corrected temperature value is implemented, the actual temperature value of the heating plate should approach the set temperature value. In this way, the corrected temperature value can be used as the implementation value in subsequent steps, so that when the heating plate is heated, the actual temperature value of the heating plate can approach or reach the set temperature value.

[0076] As an example, the set temperature value can be 550℃, the sampled temperature value can be 500℃, and the corrected temperature value can be 600℃. After implementing the corrected temperature value, the actual temperature value of the heating plate will approach 550℃.

[0077] S103, obtain the correspondence between the corrected temperature value of each temperature control zone and the current value of the metal circuit when the corrected temperature value is implemented.

[0078] In the embodiments of this application, after performing temperature calculation and analysis to obtain the corrected temperature value, the corresponding relationship between the corrected temperature value of each temperature adjustment zone and the current value of the metal circuit when the corrected temperature value is implemented can be obtained. In this way, the corrected temperature value of each temperature adjustment zone can be controlled by controlling the current value flowing through the metal circuit, so that the actual temperature value of the temperature adjustment zone approaches the set temperature value, and finally the accurate control of the actual temperature value is achieved.

[0079] Specifically, a temperature-impedance curve can be obtained between the corrected temperature value and the impedance value of the metal circuit when the corrected temperature value is applied for each temperature control zone. The calculation formulas for the impedance value and current value of the metal circuit when the corrected temperature value is applied for each temperature control zone can be obtained. Based on the temperature-impedance curve and the calculation formulas, the correspondence between the corrected temperature value and the current value of the metal circuit when the corrected temperature value is applied for each temperature control zone can be derived.

[0080] In other words, after obtaining the corrected temperature value for each temperature control zone, the impedance value corresponding to the corrected temperature value can be obtained from the temperature-impedance curve. The current value can be obtained from the impedance value, and then the correspondence between the corrected temperature value and the current value can be obtained. Subsequently, the corrected temperature value applied to each temperature control zone can be directly controlled by controlling the current value.

[0081] S104 controls the actual temperature value of each temperature-controlled zone based on the corresponding relationship and the current value of the metal circuit when implementing the corrected temperature value.

[0082] In the embodiments of this application, after obtaining the correspondence between the corrected temperature value of each temperature-adjusting zone and the current value of the metal circuit when the corrected temperature value is applied, the corrected temperature value applied to each temperature-adjusting zone can be controlled according to the correspondence and the current value of the metal circuit when the corrected temperature value is applied. When the corrected temperature value is applied to each temperature-adjusting zone, the actual temperature value of the heating plate is obtained. After calculating and analyzing the above-mentioned sampled temperature value and set temperature value, the corrected temperature value is obtained. When the corrected temperature value is applied to each temperature-adjusting zone, the actual temperature value of the heating plate approaches the set temperature value.

[0083] In other words, the actual temperature of each temperature-controlled zone can be controlled by setting the current value of the metal circuit when implementing the correction temperature value. The actual temperature value is obtained by applying the correction temperature value, and the actual temperature value obtained after applying the correction temperature value approaches the set temperature value, thereby achieving accurate temperature control of each temperature-controlled zone of the heating plate and improving the temperature control accuracy of the heating plate. In addition, accurate temperature control of each temperature-controlled zone can achieve better process results and improve the uniformity of the coating.

[0084] In the embodiments of this application, the absolute value of the difference between the actual temperature value and the set temperature value is less than a first threshold, meaning that there may be an error between the actual temperature value and the set temperature value, but this error is within an acceptable range. The first threshold can be determined according to the specific process. For example, the first threshold can be 1% of the set temperature value, or it can be 1℃, meaning that the actual temperature value and the set temperature value differ by 1℃.

[0085] When the number of sampled temperature values ​​is large, and the calculation and analysis of the sampled and set temperature values ​​are relatively accurate, the actual temperature value can be made closer to the set temperature value. By controlling the current value of the metal circuit, the correction temperature value applied to each temperature-controlled zone can be controlled, ultimately achieving an actual temperature value in each temperature-controlled zone that approaches or reaches the set temperature value. In other words, after applying the correction temperature value, the actual temperature value of each temperature-controlled zone ideally reaches the set temperature value, or ideally, the actual temperature value of each temperature-controlled zone equals the set temperature value, thus achieving stable and optimal control of the heating plate temperature.

[0086] In the embodiments of this application, when controlling the actual temperature value of the temperature-adjusting zone using the current value in the actual process, the same process conditions are used in the testing process and when sampling the temperature of the heating plate, so as to ultimately achieve precise control of the heating plate temperature. This ensures that under each fixed process condition, after the temperature of the heating plate is calibrated, the current value for adjusting each temperature-adjusting zone of the heating plate to the set temperature value is fixed.

[0087] The temperature control method for the heating plate provided in this application differs from existing temperature control methods for heating plates. Existing dual-zone heating plates adjust the temperature of two zones separately using closed-loop control. A preset temperature value is first input, and during the actual process, the temperature of each zone is measured by a temperature measuring device. A temperature command is then input, and temperature adjustment is executed through closed-loop control.

[0088] The temperature control method for the heating plate provided in this application adopts an open-loop control approach. Before the formal process, a test process is performed, involving a series of temperature data acquisitions, calculations, and analyses to obtain the required correction temperature value, ultimately yielding a directly adjustable and controllable current value. Based on different process requirements, the corresponding required current value can be obtained. During the actual execution of the formal process, directly executing the set current value will bring the actual temperature of the heating plate close to the set temperature value, achieving uniform temperature control in each temperature-adjusted zone and thus precise temperature control of the heating plate.

[0089] This application provides a temperature control method for a heating plate. The heating plate includes multiple temperature-adjustable zones, each containing a metal circuit. This means the temperature of the temperature-adjustable zone can be adjusted using the metal circuit. The method includes: sampling the temperature of each temperature-adjustable zone multiple times during multiple first fixed time periods in the process, and sampling the temperature of each temperature-adjustable zone again during a second fixed time period after the process ends, obtaining multiple sampled temperature values ​​for each temperature-adjustable zone. This provides the sampled temperature values ​​for each temperature-adjustable zone of the heating plate from the start to the end of the process. Then, the sampled temperature values ​​and set temperature values ​​are calculated and analyzed to obtain a corrected temperature value for each temperature-adjustable zone. The set temperature value is a pre-set temperature value for each temperature-adjustable zone; that is, to achieve the set temperature value, the temperature actually applied to the heating plate is the corrected temperature value. The correspondence between the calibrated temperature value and the current value of the metal circuit when the calibrated temperature value is applied is obtained for each temperature-controlled zone. This allows for control of the actual temperature value of each zone based on this correspondence and the current value of the metal circuit when the calibrated temperature value is applied. The difference between the actual temperature value and the set temperature value is less than a first threshold. In other words, the actual temperature value of each temperature-controlled zone within the heating plate can be controlled by setting the current value of the metal circuit when the calibrated temperature value is applied. The actual temperature value is obtained by applying the calibrated temperature value, and the actual temperature value obtained after applying the calibrated temperature value approaches the set temperature value, thereby achieving accurate temperature control of each temperature-controlled zone of the heating plate and improving the accuracy of temperature control. Furthermore, accurate temperature control of each temperature-controlled zone can achieve better process results and improve the uniformity of the coating.

[0090] Based on the temperature control method for a heating plate provided in the above embodiments, this application also provides a heating plate.

[0091] See Figure 2 The figure is a top view of a heating plate provided in an embodiment of this application.

[0092] The heating plate provided in this embodiment includes multiple temperature-adjustable zones 110, and the number of temperature-adjustable zones 110 can be 81. Each temperature-adjustable zone 110 is provided with at least one metal circuit 111. The temperature of the temperature-adjustable zone 110 corresponding to the metal circuit 111 can be adjusted by using the metal circuit 111, thereby realizing temperature control of each temperature-adjustable zone 110 in the heating plate.

[0093] Specifically, the distance between the metal circuit 111 and the heating surface of the heating plate is less than the second threshold, meaning the distance between the metal circuit 111 and the heating surface of the heating plate is relatively short. This allows for a shorter heat dissipation distance, improving the heating efficiency of the heating plate. The heating surface of the heating plate refers to the side of the device to be manufactured that contacts the heating plate, and the heating surface of the heating plate is used to heat the device to be manufactured.

[0094] In embodiments of this application, the thickness of the heating plate can be 15 mm, and the range of the second threshold can be 0.1 mm to 2 mm. For example, the distance between the metal circuit 111 and the heating surface can be 1.5 mm.

[0095] In existing heating plates, the heating circuit is located in the middle of the heating plate, meaning the distance between the heating circuit and the heating surface is 7.5 mm. However, in this embodiment, the distance between the metal circuit 111 and the heating surface is less than 2 mm, significantly shortening the heating distance and resulting in higher heating efficiency.

[0096] The actual temperature value of the heating plate can be controlled using the method described in the above embodiments.

[0097] Based on the temperature control method for a heating plate provided in the above embodiments, this application also provides a semiconductor device. The semiconductor device includes an electrostatic chuck, a radio frequency generator, and the heating plate described in the above embodiments, and uses the method described in the above embodiments to control the actual temperature value of the heating plate.

[0098] An electrostatic chuck includes an electrostatic chuck power supply, and an RF generator includes an RF power supply.

[0099] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, structural embodiments are basically similar to method embodiments, so they are described more simply; relevant parts can be referred to the descriptions in the method embodiments. The structural embodiments described above are merely illustrative. Those skilled in the art can understand and implement them without creative effort.

[0100] The above description is merely a preferred embodiment of this application. Although this application has disclosed preferred embodiments above, it is not intended to limit this application. Any person skilled in the art can make many possible variations and modifications to the technical solutions of this application using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the technical solutions of this application. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this application without departing from the content of the technical solutions of this application shall still fall within the protection scope of the technical solutions of this application.

Claims

1. A method for controlling the temperature of a heating plate, characterized in that, The heating plate includes multiple temperature-adjusting zones, each temperature-adjusting zone including a metal circuit; the method includes: Multiple temperature samples are taken for each temperature-controlled region during multiple first fixed time periods in the process, and temperature samples are taken for each temperature-controlled region during a second fixed time period after the process is completed, to obtain multiple sampled temperature values ​​for each temperature-controlled region; the first fixed time period is the time period during which the electrostatic chuck power supply and the radio frequency power supply are turned off, and the second fixed time period is the time period after the electrostatic chuck power supply and the radio frequency power supply are turned off. The sampled temperature value and the set temperature value are calculated and analyzed to obtain the corrected temperature value for each temperature control zone. The set temperature value is a preset temperature value for each temperature control zone. Obtain a temperature-impedance curve between the corrected temperature value of each temperature-controlled zone and the impedance value of the metal circuit when the corrected temperature value is applied; The calculation formulas for obtaining the impedance value of the metal circuit and the current value of the metal circuit when implementing the correction temperature value in each of the temperature control zones; The corresponding relationship between the corrected temperature value of each temperature-adjustment zone and the current value of the metal circuit when the corrected temperature value is applied is obtained based on the temperature-impedance curve and the calculation formula. The actual temperature value of each temperature-adjusting zone is controlled according to the correspondence and the current value of the metal circuit when the corrected temperature value is implemented. The difference between the actual temperature value and the set temperature value is less than a first threshold. The distance between the metal circuit and the heating surface of the heating plate is less than a second threshold.

2. The method according to claim 1, characterized in that, The method further includes: The process conditions for a complete process are preset, including the process time period and the set temperature value for each temperature control zone; The sampled temperature value includes a first temperature value and a second temperature value; The process of sampling temperature multiple times for each temperature-controlled region during multiple first fixed time periods in the process, and sampling temperature for each temperature-controlled region during a second fixed time period after the process is completed, to obtain multiple sampled temperature values ​​for each temperature-controlled region, includes: During the process, the set temperature value is applied to each of the temperature control zones during the process time period. Multiple first fixed time periods are set, and temperature sampling is performed multiple times for each of the temperature control zones during the multiple first fixed time periods to obtain multiple first temperature values ​​for each of the temperature control zones. After the process time period ends, a second fixed time period is set, and temperature sampling is performed on each of the temperature-adjusting zones during the second fixed time period to obtain a second temperature value for each of the temperature-adjusting zones. The step of controlling the actual temperature value of each temperature-adjusting zone based on the correspondence and the current value of the metal circuit when implementing the corrected temperature value includes: Under the stated process conditions, the actual temperature value of each temperature-adjusting zone is controlled according to the corresponding relationship and the current value of the metal circuit when the corrected temperature value is implemented.

3. The method according to claim 1, characterized in that, The first fixed time period and the second fixed time period are less than or equal to 1 second.

4. The method according to claim 1, characterized in that, The actual temperature value is equal to the set temperature value.

5. The method according to claim 1, characterized in that, The method further includes: The process conditions are repeated N times consecutively, and each temperature control region under the process conditions is sampled repeatedly, where N is a natural number greater than 2.

6. The method according to any one of claims 1-5, characterized in that, The process of sampling temperature multiple times for each temperature-controlled region during multiple first fixed time periods in the process, and sampling temperature for each temperature-controlled region during a second fixed time period after the process is completed, to obtain multiple sampled temperature values ​​for each temperature-controlled region, includes: During the process, the temperature of each temperature-controlled area is sampled M times during M first fixed time periods, and the temperature of each temperature-controlled area is sampled once during the second fixed time period after the process ends, so as to obtain M+1 sampled temperature values ​​for each temperature-controlled area, where M is a natural number greater than 50.

7. The method according to any one of claims 1-5, characterized in that, The intervals between multiple first fixed time periods are the same, and the interval between the last first fixed time period and the second fixed time period is the same as the interval between two adjacent first fixed time periods.

8. A heating plate, characterized in that, The heating plate includes multiple temperature-adjusting zones, each temperature-adjusting zone including a metal circuit, and the distance between the metal circuit and the heating surface of the heating plate is less than a second threshold. The actual temperature value of the heating plate is controlled by the method according to any one of claims 1-7.

9. The heating plate according to claim 8, characterized in that, The second threshold ranges from 0.1 mm to 2 mm.

10. The heating plate according to claim 8, characterized in that, The number of temperature-regulating zones is greater than 20.

11. A semiconductor device, characterized in that, The semiconductor device includes an electrostatic chuck, a radio frequency generator, and a heating plate as described in any one of claims 8-10.

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