Substrate temperature modeling

Abstract

A method and controller for processing a substrate are described herein. In one example, a method of processing a substrate disposed on a substrate support disposed on a cooling base includes obtaining a temperature value at a bottom of the substrate support, obtaining a temperature value associated with the cooling base, determining a substrate temperature, and processing the substrate while the substrate is disposed on the substrate support. The determined substrate temperature is based on a thermal resistivity characteristic of the substrate support, the temperature value of the bottom of the substrate support, and the temperature value associated with the cooling base.

Description

background Technical Field

[0001] Embodiments of this disclosure generally relate to a method and system for substrate temperature modeling for processing operations within a semiconductor processing chamber. Background Technology

[0002] Semiconductor chamber processing substrates are used in a wide variety of applications, including the manufacture of integrated devices and microdevices. The quality of the resulting substrates can be temperature-dependent. For example, many process formulations require starting or stopping operations after a target substrate temperature has been achieved. Failure to operate at a known substrate temperature can lead to poor production quality. However, obtaining accurate substrate temperature continues to be a challenge in this field. Many applications approximate the substrate temperature by measuring the temperatures of components in adjacent chambers within the chamber. This temperature estimation method can result in inaccurate substrate temperatures and lead to product waste, poor uniformity, low yield, process drift, and longer production downtime for resolving quality issues.

[0003] Therefore, it is necessary to improve the substrate temperature modeling within the processing chamber. Summary of the Invention

[0004] This document describes a method and controller for processing a substrate. In one example, a method for processing a substrate disposed on a substrate support on a cooling substrate includes obtaining a temperature value at the bottom of the substrate support, obtaining a temperature value associated with the cooling substrate, determining a substrate temperature, and processing the substrate while it is disposed on the substrate support. The determined substrate temperature is based on the thermal resistivity characteristics of the substrate support, the temperature value at the bottom of the substrate support, and the temperature value associated with the cooling substrate.

[0005] In another example, a non-transitory computer-readable medium has stored instructions that, when executed by a processor, cause a process to perform a method of processing a substrate disposed on a substrate support on a cooled substrate. The method includes obtaining a temperature value at the bottom of the substrate support, obtaining a temperature value associated with the cooled substrate, determining a substrate temperature, and processing the substrate while it is disposed on the substrate support. The determined substrate temperature is based on the thermal resistivity characteristics of the substrate support, the temperature value at the bottom of the substrate support, and the temperature value associated with the cooled substrate.

[0006] In another example, a controller stores a non-transitory computer-readable medium having stored instructions that, when executed by a processor, cause the processor to perform a method of processing a substrate disposed on a substrate support on a cooled substrate. The method includes obtaining a temperature value at the bottom of the substrate support, obtaining a temperature value associated with the cooled substrate, determining a substrate temperature, and processing the substrate while it is disposed on the substrate support. The determined substrate temperature is based on the thermal resistivity characteristics of the substrate support, the temperature value at the bottom of the substrate support, and the temperature value associated with the cooled substrate. Attached Figure Description

[0007] To gain a more detailed understanding of the features described above in this disclosure, a more specific description of the disclosure, which has been briefly summarized above, can be obtained by referring to the embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings are merely illustrative of embodiments of this disclosure and are not intended to limit its scope, as this disclosure may allow for other equivalent and effective embodiments.

[0008] Figure 1 This is a schematic cross-sectional side view of a processing chamber according to an embodiment of the present disclosure.

[0009] Figure 2 This is a schematic cross-sectional side view of a measuring chamber according to an embodiment of the present disclosure.

[0010] Figure 3 This is from one embodiment of the present disclosure. Figure 1 A cross-sectional view of the substrate support assembly.

[0011] Figure 4 This is an exemplary block diagram of a method for substrate temperature modeling according to embodiments of the present disclosure.

[0012] Figure 5 This is an exemplary block diagram of a method for performing process maintenance based on the thermal resistivity characteristics of a substrate support, according to embodiments of the present disclosure.

[0013] For ease of understanding, the same reference numerals have been used to identify common elements in the figures where possible. It is contemplated that elements and features of one embodiment may be advantageously incorporated into other embodiments without further description. Detailed Implementation

[0014] This disclosure relates to a method and system for substrate temperature modeling for processing operations within a semiconductor processing chamber. In various embodiments, the substrate temperature model can be used to obtain an accurate temperature of the substrate through various temperature measurements and the thermal resistivity characteristics of the substrate support. In one or more embodiments, the substrate temperature model uses readings from temperature probes within the substrate support. In one or more embodiments, the substrate temperature model uses temperature readings from a temperature-regulating fluid flowing within the substrate support. In one or more embodiments, the substrate temperature model uses a heater duty cycle of a heater disposed within the substrate support.

[0015] The modeled substrate temperature enables process feedback readings, improved closed-loop control of process operations (such as, but not limited to, etching rate, ellipticity measurement of features, selectivity, etching depth in high aspect ratio features), chamber-to-chamber matching by adjusting cell-to-cell variations, calibration (such as, but not limited to, detection of component bonding, thermal pads, and / or heater changes), preventative maintenance, and instantaneous temperature modeling and control. Thus, the methods and systems disclosed below accurately model substrate temperatures, thereby improving production quality, achieving accurate processing parameters, producing uniformity in process operation within a single chamber, achieving chamber-to-chamber uniformity, improving calibration, and enabling substrate temperature-based process control.

[0016] Figure 1 This is a schematic cross-sectional view of an exemplary plasma processing chamber 100, shown as an etching chamber, having a substrate support assembly 106. The processing chamber 100 is used for performing... Figure 4 An exemplary chamber for the method described herein. The substrate support assembly 106 can be used in other types of plasma processing chambers, such as plasma processing chambers, annealing chambers, physical vapor deposition chambers, chemical vapor deposition chambers, and ion implantation chambers, as well as other systems in which the ability to uniformly maintain a surface or workpiece (such as a substrate) at a low-temperature processing temperature is desired.

[0017] The processing chamber 100 includes a chamber body 102 having chamber sidewalls 144 enclosing an internal volume 104, a chamber bottom 126, and a removably coupled cover 128. The chamber cover 128 is coupled to a gas panel 136 to allow gas to be supplied into the internal volume 104 through the injection device 146. In some instances, the gas panel 136 supplies plasma, purification, cleaning, treatment, and / or additive gases to the internal volume 104. The chamber cover 128 also supports an RF coil 130. The RF coil 130 can be energized by an RF power supply 134. The RF power supply 134 provides RF power to the RF coil 130 via a matching circuit 132. In some instances, the RF matching circuit 132 adjusts the RF power to a suitable impedance to improve performance in the RF coil 130. In some instances, the energized RF coil 130 excites plasma gas to generate plasma within the internal volume 104. The process gas, along with any process byproducts, is removed from the internal volume 104 through an exhaust port 148 formed in the chamber sidewall 144 or chamber bottom 126 of the chamber body 102. The exhaust port 148 is coupled to a pumping system 124, which includes a throttle valve and a pump for controlling the vacuum level within the internal volume 104.

[0018] A substrate support assembly 106 is disposed within an internal volume 104. The substrate support assembly 106 is configured to receive, support, and process a substrate thereon. In some embodiments, the substrate support assembly 106 includes an electrostatic chuck 108 (also referred to as a substrate support) having a bottom 150 and a cooling substrate 110. The electrostatic chuck 108 is configured to generate electrostatic forces to position a substrate (not shown) thereon. The electrostatic chuck 108 includes clamping electrodes 114 that are supplied with bias power from a clamping electrode power supply 120 to generate the electrostatic forces for substrate positioning. The cooling substrate 110 is configured to remove thermal energy from the substrate support assembly 106. In some embodiments, the processing chamber 100 may be a cryogenic chamber configured to reduce the temperature within the internal volume 104 to less than 0 degrees Celsius, such as 0 degrees Celsius to -90 degrees Celsius.

[0019] In some instances, the electrostatic chuck 108 may include a heater 112. The heater 112 generates heat to regulate the temperature of the substrate support assembly 106. The heater 112 is coupled to a heater power supply 118. In some instances, the heater power supply 118 supplies current to the heater 112 to generate resistive heat to regulate the temperature of the substrate support assembly 106. Conversely, the cooling substrate 110 is configured to allow a temperature-regulating fluid to flow therein. The cooling substrate 110 is coupled to a heat exchanger 116 to regulate the temperature-regulating fluid. In one instance, the heat exchanger 116 may add or remove heat from the temperature-regulating fluid outside the chamber body 102 to regulate the fluid for heat exchange within the cooling substrate 110 inside the chamber body 102.

[0020] Controller 122 is configured to receive data or input from sensor readings from multiple sensors and to send or output commands to various processing chamber components or devices. Controller 122 is equipped with or communicates with a system model (not shown) of processing chamber 100. The system model is a program configured to estimate parameters within processing chamber 100, such as gas flow rate, gas pressure, processing temperature, component rotation position, heating distribution, and / or cleaning conditions, throughout the processing and / or cleaning operation. Controller 122 is further configured to store readings and calculations. Readings and calculations include previous sensor readings, such as any previous sensor readings within processing chamber 100. Readings and calculations further include calculated values ​​stored after sensor readings are measured by controller 122 and run through the system model. Thus, controller 122 is configured to retrieve stored readings and calculations, and to save readings and calculations for future use. Maintaining previous readings and calculations allows controller 122 to adjust the system model over time to reflect a more accurate version of processing chamber 100.

[0021] The controller 122 can monitor, estimate optimization parameters, adjust start-up operations, generate alarms on the display, stop operations, start chamber downtime cycles, delay subsequent iterations of operations, start cleaning operations, stop cleaning operations, adjust heating power, and / or otherwise adjust process formulations.

[0022] Controller 122 includes a central processing unit (CPU) 142 (e.g., a processor), instruction-containing memory 138, and support circuitry 140 for the CPU 142. Controller 190 controls various items directly or via other computers and / or controllers. In one or more instances, controller 122 is communicatively coupled to at least heat exchanger 116, heater power supply 118, clamping electrode bias power supply 120, RF power supply 134, gas panel 136, pumping system 124, and auxiliary chamber components (not shown) within chamber body 102.

[0023] Figure 2 This is a schematic cross-sectional view of the measurement chamber 200. The measurement chamber 200 includes a chamber body 202 having a chamber bottom 226 disposed below a chamber sidewall 244. A chamber cover 228 is removably coupled to the chamber sidewall 244 of the chamber body 202 to define a processing volume 204 in which a removable test substrate support assembly 206 is disposed. The test substrate support assembly 206 is a functional component that is removable to be transferred to and positioned within the processing chamber 100. For example, the measurement chamber 200 is configured to receive the test substrate support assembly 206 (such as from...). Figure 1 The substrate support assembly 106 is used to perform analysis on the substrate support assembly 106 before or after processing. A measurement chamber 200 is advantageous because it can be a portable chamber configured for transport from one region to another (such as from an area near processing chamber 100 to another area near another processing chamber). In some instances, the measurement chamber 200 is used as a test chamber to measure specific data from components within it.

[0024] See back Figure 2 The chamber cover 228 has an observation port 212 that provides a line of sight to the sensing device 220 for measuring the temperature of the top surface 210 of the test substrate support assembly 206. The sensing device 220 is capable of achieving accurate temperature determination of the top surface 210 of the test substrate support assembly 206. The sensing device 220 may be an optical probe for sensing the temperature of the top surface 210. In some instances, the sensing device 220 is an optical probe, such as a non-contact etalon sensor, as disclosed in Patent No. 11,280,686 B2 and U.S. Patent Application No. 20230102821A1, which are incorporated herein by reference. In some instances, the sensing device 220 is communicatively coupled to a controller 222. In those instances, the temperature readings obtained from the sensing device 220 are stored in the controller 222 for use in calculations described later. Figure 1Compared to the controller 122 described herein, controller 222 can be a standalone controller 222. Furthermore, controller 222 can communicate with controller 122. In other instances, controller 222 is... Figure 1 Controller 122.

[0025] The measurement chamber 200 may also include a connector 214 configured to couple the test substrate support assembly 206 to at least the heater power supply 218 and the heat exchanger 216, similar to... Figure 1 The configuration. In some instances, Figure 1 The heater power supply 118 and heat exchanger 116 are coupled to connector 214.

[0026] During operation, the measurement chamber 200 can adjust the temperature of the test substrate support assembly 206 to measure calibration data. This is advantageous because calibration data in a controlled environment, such as the measurement chamber 200, can be compared with data from the processing chamber 100 during real-time operation.

[0027] Figure 3 This is an unfolded cross-sectional view of the substrate support assembly 106. The substrate support assembly 106 includes an electrostatic chuck 108 bonded to a backplate 308 via a bonding layer 326. The backplate 308 is coupled to a cooling substrate 110 via a thermal pad 310. The electrostatic chuck 108 includes a heater 112 disposed between an upper heater ceramic 302 and a lower heater ceramic 304. The upper heater ceramic 302 is disposed above the heater 112. The lower heater ceramic 304 is disposed below the heater 112. The electrostatic chuck 108 has a top surface 318. In some embodiments, the electrostatic chuck 108 has a mesa 306 disposed on the top surface 318. In some embodiments, the mesa 306 may be a single layer. In other embodiments, the mesa 306 may be structured to have a grating 320 for suspending a substrate 316 above the top surface 318. In such examples, the grating 320 may be configured to support the substrate 316 through the respective substrate contact points 322 of the grating 320. The contact points 322 of the grating 320 may be spaced apart, thereby creating a void space 324 between the gratings 320 and between the substrate 316 and the top surface 318. In some examples, gas is supplied to the void space 324 through a back-side gas supply pipe 314.

[0028] The bonding layer 326 contains a temperature sensing probe 312 disposed therein. The temperature sensing probe 312 is configured to measure the temperature of the bottom 150 of the electrostatic chuck 108. Although not shown, the temperature sensing probe 312 is coupled to the controller 122.

[0029] In operation, controller 122 can activate heater 112 to heat substrate support assembly 106 to achieve a desired temperature for substrate 316. Heater 112 provides thermal energy that radiates to upper heater ceramic 302 and lower heater ceramic 304 to heat electrostatic chuck 108. The thermal energy radiated across lower heater ceramic 304 creates a heat distribution across lower heater ceramic 304. Temperature sensing probe 312, adjacent to lower heater ceramic 304 of electrostatic chuck 108, is positioned to sense the thermal energy from lower heater ceramic 304, thereby providing a temperature value for the electrostatic chuck at least affected by heater 112. Alternatively, plasma from the internal volume 104 of processing chamber 100 can also apply thermal energy downwards to substrate support assembly 106 and ultimately to bottom 150. In that example, temperature sensing probe 312 will measure the temperature value of the thermal effect of the plasma at least through electrostatic chuck 108. In some instances, the temperature sensing probe 312 can obtain the temperature value at the bottom 150 of both the heater 112 and the thermal energy of the plasma.

[0030] Conversely, controller 122 may activate cooling substrate 110 to cool substrate support assembly 106 to achieve a desired temperature for substrate 316. As mentioned above, cooling substrate 110 is configured to allow flow of temperature-regulating fluid conditioned in heat exchanger 116. The temperature-regulating fluid can be cooled to a low temperature and, depending on the desired temperature of substrate 316, provides thermal energy to substrate support assembly 106 to balance or overcome thermal energy from, for example, heater 112 and plasma.

[0031] Figure 4 This is a block diagram illustrating a method 400 for modeling substrate temperature. (Executable) Figure 4 Method 400 is used for calibration and real-time calculation. Figure 1 and / or Figure 2 The substrate temperature within the cavity. Method 400 includes operations 402, 404, 406, and 408.

[0032] Operation 402 is an operation for obtaining the temperature value at the bottom of the substrate support. As discussed above, when various heat energies are applied to the substrate support assembly 106, the temperature sensing probe 312 can be used to obtain the temperature of the electrostatic chuck 108.

[0033] The temperature sensing probe 312 can be various types of temperature sensing devices, including but not limited to a resistance temperature detector (RTD) or a thermocouple. In some instances, the temperature sensing probe 312 can be embedded within the bonding layer 326. In some instances, the temperature sensing probe 312 can be configured to make direct physical contact with the bottom 150 of the electrostatic chuck 108 for accurate measurement. In some instances, the temperature sensing probe 312 can be configured to be closer to the cooling substrate 110 than the bottom 150 of the electrostatic chuck 108 to measure the temperature distribution of the bonding layer together with the electrostatic chuck 108 measurement. Although the temperature sensing probe 312 is depicted as a single point of measurement unit, the temperature sensing probe 312 can include multiple sensing points. In some instances, the temperature sensing probe 312 can be an elongated sensing device to capture temperature measurements across the length of the bottom 150 of the electrostatic chuck 108. In some instances, as represented by the temperature sensing probe 312, multiple temperature sensing probes can be used to measure the temperature at multiple points along the surface of the bottom 150 of the electrostatic chuck 108.

[0034] Temperature sensing probe 312 is configured to provide temperature measurements from approximately -100 degrees Celsius to approximately 400 degrees Celsius. In some instances, as discussed above, temperature sensing probe 312 is configured to relay the measured temperature to controller 122. In some instances, controller 122 may calculate the average temperature measured by multiple probes across the bottom 150 of electrostatic chuck 108.

[0035] Operation 404 is an operation for obtaining a temperature value associated with the cooling substrate 110. As discussed above, the cooling substrate 110 can provide thermal energy to regulate the temperature of the substrate support assembly 106.

[0036] In some instances, the cooling substrate 110 includes flow paths within which a temperature-regulating fluid flows to provide heat to the substrate support assembly 106. The temperature-regulating fluid can be regulated by an external heat exchanger 116. In some instances, the heat exchanger 116 may be a plate heat exchanger, a shell-and-tube heat exchanger, or the like, capable of regulating the temperature-regulating fluid to temperatures from about -100 degrees Celsius to about 400 degrees Celsius.

[0037] In some instances, the temperature of the cooling substrate can be measured directly from the temperature-regulated fluid entering chambers 100, 200. In other instances, the temperature can be obtained from a temperature sensing device (not shown) positioned between the outlet of heat exchanger 116 and the inlet of cooling substrate 110. In some instances, the temperature can be obtained from a temperature sensing device (not shown) positioned between the outlet of cooling substrate 110 and the inlet of heat exchanger 116 for steady-state measurement. In other instances, the temperature of cooling substrate 110 can be obtained from a temperature element disposed within cooling substrate 110, similar to temperature sensing probe 312. In some instances, the temperature of cooling substrate 110 can be obtained from measuring the temperature-regulated fluid flowing toward cooling substrate 110 within heat exchanger 116 (such as on a fluid conduit coupling heat exchanger 116 and cooling substrate 110).

[0038] The temperature associated with the cooling substrate 110 obtained from the method described above is provided to the controller 122. In some instances, the controller 122 may calculate an average temperature in instances where multiple temperatures associated with the cooling substrate 110 are measured.

[0039] Operation 406 is an operation for determining the substrate temperature based on the thermal resistivity characteristics of the electrostatic chuck 108, the temperature value at the bottom of the substrate support, and the temperature value associated with the cooling substrate 110.

[0040] As mentioned above, the temperature value at the bottom of the substrate support (or electrostatic chuck) is provided to, for example, controller 122 as an input to Equation 1 shown below. Similarly, the temperature value associated with the cooling substrate 110 is provided to, for example, controller 122 as an input to Equation 1 shown below.

[0041] The temperature of substrate 316 can be calculated using Equation 1. Equation 1 is used to accurately model the temperature of substrate 316 within a temperature range of about 0.1 degrees Celsius to about 5 degrees Celsius (such as about 1 degree Celsius to about 4 degrees Celsius, such as about 1 degree Celsius to about 3 degrees Celsius, such as about 2.8 degrees Celsius below the actual substrate temperature).

[0042] - - Equation 1

[0043] in: T w =Temperature of substrate 316 [Klvin] T pr =Temperature of probe 312 [Klver] R top =Thermal resistance [K / W] spanning the substrate 316, mesa 306, and upper heater ceramic 302 R c2 =Thermal resistance of the lower heater ceramic 304 [K / W] R b =Thermal resistance across bonding layer 326 and backplate 308 [K / W] T cb =Cooling substrate temperature 110 [Klver] q = Total heat transfer rate generated by RF power 134 and heater 112 [W] See back Figure 3 The figure shows the thermal resistivity in Equation 1. top It is a combination of thermal resistances spanning the substrate 316, the mesa 306, and the upper heater ceramic 302. c2 R is the thermal resistance of the 304 ceramic in the lower heater. b This is the thermal resistance spanning the bonding layer 326 and the backplate 308. For ease of understanding, this can be achieved by using a measurement chamber (such as one capable of accurately measuring the temperature of the substrate 316)... Figure 2 The thermal resistivity is calculated by performing a calibration operation within the measurement chamber.

[0044] For example, Figure 3 The substrate support assembly 106 shown can be positioned using the sensing device 220. Figure 2 The temperature of the substrate 316 or the top surface 210 is measured within the measurement chamber. In some instances, the thermal resistivity of the substrate 316 is known and does not need to be measured for R. top The calculation. In other words, the known resistivity of the substrate can be input into the controller 222 to be incorporated into R. top The substrate support assembly 206 is coupled to the heater power supply 218 and the heat exchanger 216 via connector 214. The heater 224 within the substrate support assembly 206 provides heat energy to the substrate support assembly 206 at a known or calibrated rate. In some instances, the heat exchanger 216 provides heat energy to the substrate support assembly 206 at a known or calibrated rate. The temperature of the substrate 316 or top surface 210 is measured by sensing device 220 to provide T in Equation 1. w The value of . Next, equations 2 and 3 can be used by using equation 1 to use the value of each R. c2 and R b The known calibration value (otherwise referred to as the region) determines R. top Thermal resistivity.

[0045] = Equation 2

[0046] in: R b=Thermal resistance across bonding layer 326 and backplate 308 [K / W] T pr =Probe temperature [Klver] T cb =Cooling substrate temperature 110 [Klver] q = heat transfer rate [W] = Equation 3 in: R c2 =Thermal resistance of the lower heater ceramic 304 [K / W] T w =Temperature of substrate 316 [Klvin] T pr =Temperature of probe 312 [Klver] q = Total heat transfer rate generated by heater 224 and exchanger 216 [W] In some instances, multiple calculated values ​​from the above equations can be provided to the model to improve accuracy. For example, in R... top The calibration rate of thermal energy is changed during the calculation. Various scenarios can be executed to provide different data points for any of the thermal resistivity characteristics. These measured or calculated values ​​can be plotted via controller 222 to perform fitting operations, such as polynomial fitting or linear fitting, to obtain the absolute, average, or standard deviation of the dataset. Additionally, the model can extrapolate or interpolate to obtain accurate resistivity R. top R c2 and / or R b As discussed above, the advantage of this method for obtaining such thermal resistivity characteristics is that it eliminates the need for dimensional measurements of the substrate support structure. Instead, the structure is measured to obtain an accurate thermal resistivity. This method enables the measurement of various substrate support structures for analysis, and is not limited to the structures of substrate support assemblies 106 and 206, such as... Figures 1 to 3 As shown in the image.

[0047] Once R is determined top The substrate support assembly 106 is positioned within the processing chamber 100 for processing the substrate. In non-plasma processing operations, the controller 122 is now able to accurately model the temperature of the substrate positioned on the electrostatic chuck 108. In plasma processing operations, the controller 122 is able to accurately model the temperature of the substrate positioned on the electrostatic chuck 108, with adjustments made to account for the thermal energy applied to the substrate support assembly 106 from the plasma. For example, R can be calibrated in the processing chamber 100 using Equation 4. top .

[0048] Equation 4

[0049] in: T w =Temperature of substrate 316 [Klvin] T pr =Temperature of probe 312 [Klver] R top =Thermal resistance [K / W] spanning the substrate 316, mesa 306, and upper heater ceramic 302 R c2 =Thermal resistance of the lower heater ceramic 304 [K / W] R b =Thermal resistance across bonding layer 326 and backplate 308 [K / W] T cb =Cooling substrate temperature 110 [Klver] q = Total heat transfer rate [W] The total heat transfer rate q can be equal to the rate of thermal energy of the plasma minus the known heat transfer rate from the processing operation. Therefore, the temperature of the substrate model takes into account the processing heat energy present in the processing chamber 100 but possibly not in the measurement chamber 200 to obtain the processing R. top Further calibration of the R-conditions for the processing. top The advantage is that the thermal operation of heater 112 can be actively controlled to take into account other thermal energy within the processing chamber 100.

[0050] The exemplary model above illustrates the use of a specific chamber architecture; however, this model can be applied to several different types of chambers with different internal structures to obtain their corresponding thermal resistivity characteristics. For example, other thermal resistivity characteristics can be analyzed and incorporated into the model. In some instances, back-side gas can be supplied to the platform 306 through back-side gas supply pipe 314 to fill the void space 324. The corresponding thermal resistivity characteristics of each back-side gas at different pressures can be analyzed. Thus, the model can be further improved by incorporating additional resistivity of the back-side gas used during processing within the substrate support assembly 106.

[0051] Referring back to operation 406, the temperature of substrate 316 can be determined based on the thermal resistivity characteristics of electrostatic chuck 108, the temperature value at the bottom of substrate support, and the temperature value associated with cooling substrate 110.

[0052] Operation 408 is the operation of processing the substrate set on the substrate support using the substrate temperature determined above.

[0053] Many processing formulations may use specific, customized processing steps / operations that can be altered after the target substrate temperature is reached, or may require a specific substrate temperature to achieve better processing conditions. In some instances, process formulations may require higher substrate temperatures for better processing, such as etching or deposition, necessitating heater 112 to provide heat to the target work. This model provides the substrate temperature in real time to offer better control over heater 112. While heater 112 is used in the examples mentioned, various devices for providing heat can be used for better control. By obtaining an accurate substrate temperature, processing formulations can be precisely controlled to minimize waste and produce higher-quality processed substrates.

[0054] In some instances, operation 408 is improved through the accuracy of the substrate temperature due to the implementable control schemes. For example, closed-loop control can be achieved by incorporating the model discussed above into the control system of the processing chamber 100. In some instances, the cooling substrate 110 can be controlled based on a target substrate temperature, taking into account various thermal energies present within the processing chamber 100 to achieve the target substrate temperature. In some instances, the operation of the heater 112 can be controlled to account for any irregularities that may occur within the processing chamber 100, such as temperature drift of the temperature regulating fluid or plasma density irregularities.

[0055] See now Figure 5 It is a block diagram illustrating a method 500 for performing process maintenance based on thermal resistivity characteristics through operation 510.

[0056] Operation 510 performs process maintenance based on the thermal resistivity characteristics of the substrate support assembly 206. As mentioned above, the thermal resistivity characteristics can be determined for any substrate support assembly 206. Data logs can be recorded, entered, and maintained to provide information about the specific substrate support assembly 206. For example, a data log can be obtained from the calculated resistivity of the substrate support assembly before processing. After a predetermined number of processing cycles, the calculated resistivity can be compared later with the same substrate support assembly to determine if the thermal resistivity characteristics have changed. If the thermal resistivity characteristics have changed, the substrate support may require maintenance. Changes identified in the thermal resistivity characteristics can indicate feature failure, wear, or degradation within the substrate support.

[0057] In some instances, changes in thermal resistivity characteristics within the processing chamber 100 can be obtained by calculating the substrate temperature. For example, changes in substrate temperature during steady-state operation indicate changes in thermal resistivity characteristics. The obtained changes in thermal resistivity characteristics can indicate real-time process drift caused by faulty components within the substrate support.

[0058] Calibration can be performed in real time and by comparing the processed values ​​in the measurement chamber 200. Since the controller 222 can be configured to acquire, store, and evaluate temperature readings from the sensing device 220, the controller 222 can use the processor to establish data trend lines and alert for deviations from the desired process conditions.

[0059] Although the foregoing relates to embodiments of this disclosure, other and further embodiments of this disclosure may be designed without departing from its basic scope, which is defined by the foregoing claims.

Claims

1. A method for processing a substrate on a substrate support disposed on a cooling substrate, the method comprising: Obtain the temperature value at the bottom of the substrate support; Obtain the temperature value associated with the cooling substrate; The substrate temperature is determined based on the following: Thermal resistivity characteristics of the substrate support. The temperature value at the bottom of the substrate support, and The temperature value associated with the cooling substrate; and The substrate is processed when it is disposed on the substrate support.

2. The method of claim 1, wherein determining the substrate temperature is further based on the temperature value of a backside gas configured to flow below the backside of the substrate.

3. The method of claim 1, wherein the temperature value at the bottom of the substrate support is obtained from a temperature probe disposed on the back side of the electrostatic chuck.

4. The method of claim 1, wherein the temperature value associated with the cooling substrate is obtained from a temperature measuring device coupled to a temperature-regulating fluid configured to flow through the cooling substrate.

5. The method of claim 1, wherein determining the substrate temperature is further based on the heat transfer rate of the substrate support heater.

6. The method of claim 1, wherein the substrate temperature is determined by the following: - - in: T w =The substrate temperature [Klver] T pr =Probe temperature [Klver] for measuring the temperature at the bottom of the substrate support. R top =First thermal resistance [K / W] of the upper heater ceramic spanning the substrate, the platform, and the substrate support. R c2 =Second thermal resistance [K / W] of the lower heater ceramic of the substrate support member R b =Third thermal resistance [K / W] spanning the bonding layer and backplate of the substrate support. T cb =Temperature measurement results of the cooling substrate [Klvin] q = total heat transfer rate [W].

7. The method of claim 1, wherein the substrate temperature is accurate within 2.8 degrees Celsius.

8. The method of claim 1, wherein the substrate support is disposed in an etched or deposited semiconductor chamber.

9. The method of claim 1, wherein the determined substrate temperature is used in closed-loop control to process the substrate.

10. A non-transitory computer-readable medium having stored instructions, which, when executed by a processor, cause the processor to perform a method of processing a substrate on a substrate support disposed on a cooling substrate in a processing chamber, the method comprising: Obtain the temperature value at the bottom of the substrate support; Obtain the temperature value associated with the cooling substrate; The substrate temperature is determined based on the following: Thermal resistivity characteristics of the substrate support. The temperature value at the bottom of the substrate support, and The temperature value associated with the cooling substrate; and The substrate is processed when it is disposed on the substrate support.

11. The non-transitory computer-readable medium of claim 10, wherein determining the substrate temperature is further based on the temperature value of a backside gas configured to flow below the backside of the substrate.

12. The non-transitory computer-readable medium of claim 10, wherein the temperature value at the bottom of the substrate support is obtained from a temperature probe disposed on the back side of the electrostatic chuck.

13. The non-transitory computer-readable medium of claim 10, wherein determining the substrate temperature is further based on the operating value of the substrate support heater.

14. The non-transitory computer-readable medium of claim 10, wherein the substrate support is disposed in an etched or deposited semiconductor chamber.

15. The non-transitory computer-readable medium of claim 10, wherein the determined substrate temperature is used in closed-loop control to process the substrate.

16. A controller for storing a non-transitory computer-readable medium having stored instructions, which, when executed by a processor, cause the processor to perform a method of processing a substrate on a substrate support disposed on a cooling substrate in a processing chamber, the method comprising: Obtain the temperature value at the bottom of the substrate support; Obtain the temperature value associated with the cooling substrate; The substrate temperature is determined based on the following: Thermal resistivity characteristics of the substrate support. The temperature value at the bottom of the substrate support, and The temperature value associated with the cooling substrate; and The substrate is processed when it is disposed on the substrate support.

17. The controller of claim 16, wherein determining the substrate temperature is further based on the temperature value of a backside gas configured to flow below the backside of the substrate.

18. The controller of claim 16, wherein the temperature value at the bottom of the substrate support is obtained from a temperature probe disposed on the back side of the electrostatic chuck.

19. The controller of claim 16, wherein the determination of the substrate temperature is further based on the heat transfer rate of the substrate support heater.

20. The controller of claim 16, wherein the substrate temperature is determined by: - - in: T w =The substrate temperature [Klver] T pr =Probe temperature [Klver] for measuring the temperature at the bottom of the substrate support. R top =First thermal resistance [K / W] of the upper heater ceramic spanning the substrate, the platform, and the substrate support. R c2 =Second thermal resistance [K / W] of the lower heater ceramic of the substrate support member R b =Third thermal resistance [K / W] spanning the bonding layer and backplate of the substrate support. T cb =Temperature measurement results of the cooling substrate [Klvin] q = total heat transfer rate [W].

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