MODEL-BASED CONTROL METHOD, MODEL-BASED CONTROL SYSTEM, AND PROGRAM
By adopting a model-based control method in the semiconductor manufacturing process, using the weighted average temperature and multi-input multi-output state space model, the problem of slow temperature distribution adjustment speed is solved, and faster and more accurate temperature control is achieved.
Patent Information
- Application Number
- JP2022008643
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-01-24
- Publication Date
- 2025-04-18
- Estimated Expiration
- 2042-01-24
AI Technical Summary
In the semiconductor manufacturing process, with the increase in the demand for precision control, especially high-precision control of the temperature distribution of the base plate, it is difficult for the prior art to quickly and effectively adjust the temperature distribution to the target temperature distribution.
Using a model-based control method, the temperature distribution is controlled using a weighted average temperature and a multi-input multi-output state space model by obtaining temperature control data for each independently controllable region.
This achieves a faster adjustment of the temperature distribution to the target temperature distribution, improving the efficiency and accuracy of temperature control.
Smart Images

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Abstract
Description
[Technical field]
[0001] The present disclosure relates to a model-based control method, a model-based control system, and a program. [Background technology]
[0002] In recent semiconductor manufacturing processes, there is a demand for even higher precision control as features become finer. In particular, it is important to control the temperature distribution of the substrate being processed in the manufacturing process with high precision. In order to control the temperature distribution of the substrate with high precision, it is conceivable to divide the stage on which the substrate is placed into multiple regions and control the temperature of each region independently. However, as the number of regions on the stage that can be independently temperature-controlled increases, each region becomes smaller, making it difficult to provide both heaters and temperature sensors in all regions.
[0003] To avoid this, a technique is known in which the temperature of each area of a stage that can be controlled independently is estimated from the relationship between the resistance value and temperature of a heater provided in each area of the stage (see, for example, Patent Document 1 below). The resistance value of the heater is calculated from the measured values of the voltage and current supplied to the heater. This eliminates the need to provide a temperature sensor in addition to the heater in each area of the stage, and allows the stage to be provided with more areas that can be controlled independently. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] Patent Publication No. 2021-9769 Summary of the Invention [Problem to be solved by the invention]
[0005] The present disclosure provides a technique that can more quickly bring the temperature distribution of a temperature control member closer to a target temperature distribution. [Means for solving the problem]
[0006] A model-based control method according to an embodiment of the present disclosure includes steps a), b), c), d), and e). In step a), temperature control data is obtained, including data on the temperature of each zone in a temperature control member provided in a processing device and having a plurality of zones whose temperatures can be controlled individually. In step b), for each zone, the temperature of the other zones is identified, which is a weighted average of the temperatures of the other zones by a weighting coefficient determined according to the magnitude of heat transfer between the other zones. In step c), parameters of a multi-input single-output state space model are identified for each zone using the identified temperatures of the other zones and the temperature control data. In step d), a multi-input multi-output state space model is created by assigning the identified parameters of the multi-input single-output state space model to each element of the multi-input multi-output state space model. In step e), the temperature of each zone of the temperature control member is controlled using the multi-input multi-output state space model. Effect of the Invention
[0007] According to the present disclosure, the temperature distribution of the temperature control member can be made to approach the target temperature distribution more quickly. [Brief description of the drawings]
[0008] [Figure 1] FIG. 1 is a diagram showing an example of a configuration of a substrate processing system. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing an example of the substrate processing apparatus. [Diagram 3] FIG. 3 is a top view illustrating an example of an electrostatic chuck and an edge ring. [Figure 4] FIG. 4 is a diagram illustrating an example of a heater control circuit. [Diagram 5] FIG. 5 is a diagram illustrating an example of a control device included in the substrate processing apparatus according to the first embodiment. [Figure 6A] FIG. 6A is a diagram showing an example of temperature control condition data. [Figure 6B] FIG. 6B is a diagram showing an example of the temperature control data. [Figure 7] FIG. 7 is a diagram illustrating an example of a model data generating device. [Figure 8] FIG. 8 is a flowchart illustrating an example of processing performed by the model data generating device. [Figure 9] FIG. 9 is a diagram for explaining an example of a method for determining a weighting coefficient. [Figure 10] FIG. 10 is a flow chart showing an example of a process performed by the substrate processing apparatus. [Figure 11] FIG. 11 is a diagram showing an example of temperature changes in each zone in the temperature control of the comparative example. [Figure 12] FIG. 12 is a diagram showing the zones to be evaluated. [Figure 13] FIG. 13 is a diagram showing an example of temperature changes in each zone in the temperature control of this embodiment. [Figure 14] FIG. 14 is a diagram illustrating an example of a control device included in the substrate processing apparatus according to the second embodiment. [Figure 15] FIG. 15 is a diagram illustrating an example of a procedure for updating the coefficients of the model data. [Figure 16] FIG. 16 is a diagram illustrating an example of the effect of adaptive control. [Figure 17] FIG. 17 is a flowchart illustrating an example of a procedure for managing model data using adaptive control. [Figure 18] FIG. 18 is a diagram for explaining an example of a method for determining weighting coefficients when zones made of different materials are included. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0009] Hereinafter, embodiments of the model-based control method, the model-based control system, and the program disclosed in the present application will be described in detail with reference to the drawings. Note that the disclosed model-based control method, the model-based control system, and the program are not limited to the embodiments.
[0010] Incidentally, when controlling the temperature distribution of a stage having multiple regions that can be independently temperature controlled, the power supplied to the heaters provided in each region is controlled so that the temperature of each region becomes a target temperature. The power supplied to the heaters provided in each region is often controlled by so-called PID (Proportional-Integral-Differential) control, in which the control amount is determined based on the deviation between the control result and the target value.
[0011] In PID control, as the control result approaches the target value, the deviation between the control result and the target value becomes smaller, and the control amount becomes smaller. Therefore, it takes a long time for the control result to stabilize near the target value. In addition, when controlling the temperature distribution of the stage, the temperature of each area of the stage is affected by the temperature of other areas, so it is difficult to stabilize the temperature of each area by simply controlling the power supplied to the heater based on the temperature of the area where the heater is provided. Therefore, it takes a long time to bring the temperature of each area closer to the target value.
[0012] Therefore, the present disclosure provides a technique that can more quickly bring the temperature distribution of a temperature control member such as a heater closer to a target temperature distribution.
[0013] (First embodiment) [Configuration of substrate processing system 1] 1 is a system configuration diagram showing an example of the configuration of a substrate processing system 1. The substrate processing system 1 includes a substrate processing apparatus 10 and a model data creation device 20. The substrate processing apparatus 10 and the model data creation device 20 are connected via a communication network N such as a LAN (Local Area Network). The substrate processing system 1 is an example of a model-based control system.
[0014] The substrate processing apparatus 10 has a stage on which a substrate is placed. The stage has a plurality of zones. The temperature of each zone can be controlled individually. The substrate processing apparatus 10 measures temperature data of each zone of the stage on which a substrate is placed under various processing conditions. Then, the measured temperature data of each zone is transmitted to the model data creation apparatus 20 via the communication network N as temperature control data.
[0015] The substrate processing apparatus 10 receives model data, which will be described later, from the model data creation device 20 via the communication network N. The substrate processing apparatus 10 controls the temperature of each zone of the stage using the model data received from the model data creation device 20. The substrate processing apparatus 10 then performs processing, such as etching, on the substrate placed on the stage.
[0016] The model data creating device 20 receives temperature control data from the substrate processing apparatus 10 via the communication network N, and creates model data using the received temperature control data. The procedure for creating the model data will be described later. Then, the model data creating device 20 transmits the created model data to the substrate processing apparatus 10 via the communication network N.
[0017] [Structure of the substrate processing apparatus 10] Fig. 2 is a schematic cross-sectional view showing an example of the substrate processing apparatus 10. Fig. 2 shows a capacitively coupled parallel plate plasma etching apparatus as an example of the substrate processing apparatus 10. The substrate processing apparatus 10 includes a control apparatus 100 and an apparatus main body 110.
[0018] The apparatus body 110 includes a processing vessel 112 formed into a substantially cylindrical shape from, for example, aluminum, etc. The surface of the processing vessel 112 is anodized. The processing vessel 112 is grounded.
[0019] A stage 116 is provided within the processing vessel 112. The stage 116 holds the substrate W on its upper surface by suction, and controls the temperature of the substrate W. Note that, in this embodiment, the substrate W is a substantially disk-shaped substrate for manufacturing a semiconductor device, but the disclosed technology is not limited to this. In another embodiment, the substrate W may be a shape other than a substantially disk-shaped shape, such as a rectangular plate. In another embodiment, the substrate W may be a substrate for manufacturing a device other than a semiconductor device, such as an FPD (Flat Panel Display) substrate.
[0020] The stage 116 has an electrostatic chuck 118 and a base 120. A substrate W to be processed is placed on the upper surface of the electrostatic chuck 118. The base 120 is formed in a substantially disk shape from a conductive member such as aluminum. The base 120 also functions as a lower electrode. The base 120 is supported by a support 114. The support 114 is a substantially cylindrical member extending upward from the bottom of the processing vessel 112.
[0021] A radio frequency (RF) power supply HFS is electrically connected to the base 120 via a matching unit MU1. The RF power supply HFS generates RF power for generating plasma and supplies the generated RF power to the base 120. The frequency of the RF power for generating plasma is within a range of 27 to 100 MHz, and is 40 MHz in one example. The matching unit MU1 has a circuit for matching the output impedance of the RF power supply HFS with the input impedance of the load side (for example, the base 120 side).
[0022] Further, an RF power supply LFS is electrically connected to the base 120 via a matching unit MU2. The RF power supply LFS generates RF power (RF bias power) for attracting ions into the substrate W, and supplies the generated RF bias power to the base 120. The frequency of the RF bias power is within a range of 400 kHz to 13.56 MHz, and is a frequency of 3 MHz in one example. The matching unit MU2 has a circuit for matching the output impedance of the RF power supply LFS with the input impedance of the load side (for example, the base 120 side).
[0023] An electrostatic chuck 118 is disposed on the base 120. The electrostatic chuck 118 attracts the substrate W by electrostatic force and holds the substrate W on the upper surface of the electrostatic chuck 118. The electrostatic chuck 118 has an electrode E1 in a main body formed of, for example, ceramic. A DC power supply 122 is electrically connected to the electrode E1 via a switch SW1. The electrode E1 generates an electrostatic force on the surface of the electrostatic chuck 118 by a DC voltage supplied from the DC power supply 122.
[0024] An annular edge ring ER is disposed on the upper surface of the base 120 around the electrostatic chuck 118 so as to surround the substrate W. The edge ring ER improves the uniformity of the plasma processing on the substrate W. The edge ring ER is made of a material, such as silicon or quartz, that is appropriately selected depending on the plasma processing to be performed. The edge ring ER is also called a focus ring.
[0025] Further, the electrostatic chuck 118 is provided with a plurality of heaters HT. In this embodiment, the upper surface of the electrostatic chuck 118 is divided into a plurality of zones Z, for example, as shown in Fig. 3. In the example of Fig. 3, the upper surface of the electrostatic chuck 118 is divided into, for example, 15 zones Z. Note that the number of zones Z is not limited to 15, and may be more than 15 or less than 15. Furthermore, the method of dividing the zones Z is not limited to the example of Fig. 3, and may be a division method such as a lattice shape, a concentric circle shape, a radial shape, or a combination thereof.
[0026] In this embodiment, one heater HT is provided for each zone Z. As another embodiment, two or more heaters HT may be provided for each zone Z, and the number of heaters HT may differ between the zones Z. In this embodiment, a heater HT is also provided on the lower surface of the edge ring ER. That is, in this embodiment, a total of 16 heaters HT are provided in the electrostatic chuck 118 and the edge ring ER. In this embodiment, the edge ring ER is also treated as one zone Z. Therefore, in this embodiment, a total of 16 zones Z are provided in the electrostatic chuck 118 and the edge ring ER. The electrostatic chuck 118 and the edge ring ER are examples of a temperature control member. In this embodiment, the temperature control member is the electrostatic chuck 118 that has multiple zones that can be individually temperature controlled and controls the temperature distribution of the substrate W, but the disclosed technology is not limited to this. The temperature control member may be a member other than the electrostatic chuck 118 as long as it has multiple zones that can be individually temperature controlled.
[0027] A heater control circuit 160 is connected to each heater HT. Each heater HT generates heat by power individually supplied from the heater control circuit 160, and heats the corresponding zone Z. FIG. 4 is a diagram showing an example of the heater control circuit 160. The heater control circuit 160 has a plurality of control blocks 161-1 to 161-n and a measurement unit 165. Note that, hereinafter, the plurality of control blocks 161-1 to 161-n will be referred to collectively as control block 161 without distinguishing between them.
[0028] The control block 161 is provided for each heater HT provided in each zone Z, and supplies power to the corresponding heater HT. The control block 161 has an ammeter 163, a voltmeter 164, and a switch SW2.
[0029] The switch SW2 is turned on and off under control of the control device 100. As a result, the power supplied from the power source 166 to the corresponding heater HT is adjusted to a power corresponding to the on and off duty ratio of the switch SW2. The ammeter 163 measures the current supplied from the power source 166 to the corresponding heater HT, and outputs the measured current value to the measurement unit 165. The voltmeter 164 measures the voltage supplied from the power source 166 to the corresponding heater HT, and outputs the measured voltage value to the measurement unit 165.
[0030] The measurement unit 165 measures the resistance value of each heater HT based on the measured current and voltage values output from each control block 161. Then, the measurement unit 165 outputs data on the measured resistance value for each heater HT to the control device 100.
[0031] 2, the explanation will be continued. A flow path 124 is formed inside the base 120. A coolant is supplied to the flow path 124 from a chiller unit (not shown) provided outside the processing vessel 112 via a pipe 126a. The coolant supplied to the flow path 124 is returned to the chiller unit via a pipe 126b. The temperature of the coolant is controlled by the chiller unit.
[0032] An upper electrode 130 is provided in the processing vessel 112. The upper electrode 130 is disposed above the stage 116 so as to face the base 120. In this embodiment, the base 120 and the upper electrode 130 are disposed so as to be substantially parallel to each other.
[0033] The upper electrode 130 is supported on the upper part of the processing vessel 112 via an insulating shielding member 132. The upper electrode 130 includes an electrode plate 134 and a support 136. The electrode plate 134 faces the processing space S between the stage 116 and the upper electrode 130, and has a plurality of gas discharge ports 134a. The electrode plate 134 may be made of a low-resistance conductor or semiconductor that generates little Joule heat.
[0034] The support 136 is formed of a conductive material such as aluminum, and detachably supports the electrode plate 134 from above. The support 136 may have a water-cooled structure. A gas diffusion chamber 136a is provided inside the support 136. A plurality of gas flow ports 136b that communicate with the gas discharge port 134a extend downward from the gas diffusion chamber 136a. The support 136 is also provided with a gas inlet 136c that introduces gas into the gas diffusion chamber 136a. A pipe 138 is connected to the gas inlet 136c.
[0035] A gas source group 140 is connected to the pipe 138 via a valve group 142 and a flow rate controller group 144. The valve group 142 has a plurality of opening and closing valves. The flow rate controller group 144 has a plurality of flow rate controllers such as mass flow controllers. The gas source group 140 has gas sources for a plurality of types of gases required for plasma processing. The plurality of gas sources in the gas source group 140 are connected to the pipe 138 via the corresponding opening and closing valves and corresponding mass flow controllers.
[0036] 2, one or more gases from one or more selected gas sources among a plurality of gas sources included in a gas source group 140 are supplied to a pipe 138. The gas supplied to the pipe 138 diffuses in the gas diffusion chamber 136a and is discharged in a shower-like manner into the processing space S through the gas circulation port 136b and the gas discharge port 134a.
[0037] A ground conductor 112a is provided above the upper electrode 130 so as to cover the upper electrode 130. The ground conductor 112a is made of metal and has a substantially cylindrical shape, and is grounded via the processing vessel 112.
[0038] A deposit shield 146 is detachably provided in the processing vessel 112 along the inner wall of the processing vessel 112. The deposit shield 146 is also provided on the outer periphery of the support portion 114. The deposit shield 146 is formed, for example, by coating an aluminum material with ceramics such as Y2O3, and prevents etching by-products (so-called deposits) from adhering to the wall surface inside the processing vessel 112.
[0039] An exhaust plate 148 formed by, for example, coating an aluminum material with ceramics such as Y2O3 is provided between the support 114 and the inner wall of the processing vessel 112 at the bottom side of the processing vessel 112. An exhaust port 112e is provided below the exhaust plate 148. An exhaust device 150 is connected to the exhaust port 112e via an exhaust pipe 152. The exhaust device 150 has a vacuum pump such as a turbo molecular pump, and can reduce the pressure inside the processing vessel 112 to a desired vacuum level. An opening 112g is formed in the side wall of the processing vessel 112 for loading and unloading the substrate W. The opening 112g is opened and closed by a gate valve 154.
[0040] The operation of the apparatus main body 110 configured as described above is generally controlled by a control device 100 configured as shown in Fig. 5. The control device 100 is realized by, for example, a computer. Fig. 5 is a diagram showing an example of the control device 100 included in the substrate processing apparatus 10 in the first embodiment.
[0041] The control device 100 includes a communication I / F (interface) 101, a user I / F 102, a control unit 103, and a storage unit 104. The control unit 103 is an example of a second control unit.
[0042] The communication I / F 101 communicates with the apparatus main body 110. The communication I / F 101 also communicates with the model data creation apparatus 20 via a communication network N. The user I / F 102 provides an interface for a user of the substrate processing apparatus 10 to operate the substrate processing apparatus 10.
[0043] The storage unit 104 includes a RAM (Random Access Memory), a ROM (Read Only Memory), an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a combination of these. The storage unit 104 stores a correspondence table 1040, model data 1041, and a recipe 1042. The correspondence table 1040 is data showing the correspondence between the resistance value and temperature of the heater HT. The model data 1041 is model data showing the temperature change of the heater HT in each zone Z created by the model data creating device 20. The recipe 1042 is data including processing conditions for the substrate W, etc. The storage unit 104 also stores programs, etc.
[0044] The control unit 103 has a processor such as a CPU (Central Processing Unit) or a DSP (Digital Signal Processor). The control unit 103 executes a program stored in the storage unit 104 to realize the functions of a data collection unit 1030, a temperature control unit 1031, and a recipe execution unit 1032.
[0045] The data collection unit 1030 controls the device body 110 in response to an instruction from the model data creation device 20, and collects data on the resistance value of the heater HT provided in each zone Z under a plurality of processing conditions. The plurality of processing conditions are described in, for example, temperature control condition data shown in FIG. 6A. FIG. 6A is a diagram showing an example of temperature control condition data. The temperature control condition data exemplified in FIG. 6A includes the initial temperature of each zone, the set temperature of each zone, the power supply voltage of the power supply 166 that supplies power to the heater HT of the corresponding zone, the temperature of the coolant (chiller temperature) controlled by the chiller unit, and the like. In the temperature control condition data exemplified in FIG. 6A, n represents the number of zones, m represents the number of temperature control conditions, and SP (Set Point) represents a set value or a target value.
[0046] Then, the data collecting unit 1030 refers to the correspondence table 1040 in the storage unit 104 to identify the temperature corresponding to the collected resistance value. Then, the data collecting unit 1030 creates temperature control data including data on the temperature of each zone Z for each processing condition. For example, when PID control is performed to acquire data for modeling, control is performed while feeding back the resistance-converted temperature. Specifically, the resistance value is converted to a temperature, and the manipulated variable is determined based on the deviation between the temperature and a reference value. Note that when acquiring data by inputting a predetermined manipulated variable such as an impulse response or a step response, it is also possible to collect only the resistance values and then convert them into temperatures all at once.
[0047] The temperature of each zone Z may be acquired via the substrate W placed on the electrostatic chuck 118. The temperature distribution of the substrate W placed on the electrostatic chuck 118 can be measured by, for example, a temperature sensor using infrared rays or an optical fiber. By measuring the temperature distribution of the substrate W, the temperature of the zone Z corresponding to the region of the substrate W can be estimated.
[0048] Fig. 6B is a diagram showing an example of temperature control data. The temperature of each zone Z, the operation amount of each zone, the power supply voltage, and the chiller temperature are associated with each other in the temperature control data shown in Fig. 6B. Then, the data collecting unit 1030 transmits the generated temperature control data to the model data generating device 20 via the communication I / F 101.
[0049] When the temperature control unit 1031 receives model data from the model data creating device 20, it stores the received model data in the storage unit 104. Furthermore, when the recipe executing unit 1032 executes a recipe 1042, the temperature control unit 1031 uses the model data 1041 to specify the power to be supplied to the heater HT provided in each zone Z. Then, the temperature control unit 1031 controls the switch SW2 of the corresponding heater control circuit 160 so that the specified power is supplied to each heater HT.
[0050] The recipe execution unit 1032 controls each unit of the apparatus main body 110 based on the recipe 1042 to execute processing on the substrate W.
[0051] [Configuration of model data creation device 20] 7 is a diagram showing an example of a model data creation device 20. The model data creation device 20 is realized by, for example, a computer. The model data creation device 20 has a communication I / F 21, a user I / F 22, a control unit 23, and a storage unit 24. The control unit 23 is an example of a first control unit. The communication I / F 21 is an example of an output unit.
[0052] The communication I / F 21 communicates with the substrate processing apparatus 10 via the communication network N. The user I / F 22 provides an interface for a user of the model data creating apparatus 20 to operate the model data creating apparatus 20.
[0053] The storage unit 24 includes a RAM, a ROM, a HDD, an SSD, or a combination thereof. The storage unit 24 stores temperature control data 240 and a weighting factor 241. The temperature control data 240 includes data of the temperature of each zone Z measured under various conditions in the substrate processing apparatus 10. The weighting factor 241 is data used for creating model data. The weighting factor 241 will be described in detail later. The storage unit 24 also stores programs and the like in addition to the above.
[0054] The control unit 23 has a processor such as a CPU, a DSP, etc. The control unit 23 executes a program stored in the storage unit 24 to realize the functions of a data collection unit 230 and a model data creation unit 231.
[0055] The data collection unit 230 instructs the substrate processing apparatus 10 to create temperature control data via the communication I / F 21. Then, the data collection unit 230 receives the temperature control data from the substrate processing apparatus 10 via the communication I / F 21, and stores the received temperature control data in the storage unit 24.
[0056] The model data creation unit 231 creates model data that models temperature changes of the plurality of heaters HT by referring to the temperature control data 240 and the weighting coefficient 241. Then, the model data creation unit 231 transmits the created model data to the substrate processing apparatus 10 via the communication I / F 21.
[0057] [Processing of model data creation device 20] Fig. 8 is a flowchart showing an example of the process of the model data creation device 20. The process shown in Fig. 8 is realized by the control unit 23 reading a program from the storage unit 24 and executing the read program. The process shown in Fig. 8 and Fig. 10 described later is an example of a model-based control method.
[0058] First, the data collecting unit 230 instructs the substrate processing apparatus 10 to collect temperature control data, and receives the temperature control data from the substrate processing apparatus 10 (S100). Then, the data collecting unit 230 stores the received temperature control data in the storage unit 24. Step S100 is an example of the process a).
[0059] Next, the model data creation unit 231 initializes the value of a variable i to 1 (S101). Then, the i-th zone Z is selected (S102). Then, the model data creation unit 231 calculates a weighted average of the temperatures of the zones Z other than the i-th zone Z (S103). Step S103 is an example of the process b).
[0060] Here, in this embodiment, the temperature of each zone Z is expressed using a discretized state equation. In the following, a case where an ARX (Auto-Regressive eXogenous) model is used as an example of the discretized state equation will be described. In the following, data of the ARX model may be described as model data. The ARX model is an example of a regression model. In addition, the regression model is an example of a state space model that outputs (specifies) parameters of a multiple-input single-output, and the coefficients of the regression model are an example of parameters of a multiple-input single-output state space model. The temperature x(t) of each zone Z is expressed, for example, as in the following formula (1) using the ARX model.
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[0061] In the above formula (1), x i (t) represents the temperature of the i-th zone Z. u i v(t) represents the manipulated variable of the power supplied to the heater HT of the i-th zone Z. v(t) represents the magnitude of the power supply voltage supplied to the heater HT of each zone Z. z(t) represents the temperature of the coolant supplied to the flow path 124 inside the base 120 from a chiller unit (not shown). i represents the autoregressive coefficient for the i-th zone Z, and b i represents the coefficient of temperature of zone Z different from the i-th zone Z. c i represents the coefficient of the manipulated variable of the power supplied to the heater HT of the i-th zone Z, and d i represents the coefficient of the cross term between the power supply voltage supplied to the heater HT of the i-th zone Z and the magnitude of the manipulated variable. e i represents the coefficient of the coolant temperature affecting the i-th zone Z, and f i represents the constant term for the i-th zone Z.
[0062] In step S103, in the above (1), the term expressed by the following formula (2) is calculated as a weighted average of the temperatures of the zones Z other than the i-th zone Z.
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[0063] In the above formula (2), w ij is a positive weighting coefficient that represents the magnitude of heat transfer between the i-th zone Z and a j-th zone Z that is different from the i-th zone Z and sums up to 1. In this embodiment, the weighting coefficient w is determined based on the area of the boundary surface between adjacent zones Z. Specifically, for example, as shown in FIG. 9, when the second to fourth zones Z2 to Z4 are adjacent to the periphery of the first zone Z1 and the area of the boundary surface between zone Z1 and zones Z2 to Z4 is the same, the weighting coefficient w ij , w 12 =w 13 =w 14 9, it is assumed that the materials of the zones Z1 to Z4 are the same. In addition, when the thickness of the boundary surface between the zone Z1 and the zones Z2 to Z4 is the same, the weighting coefficient w 12 , w 13 , and w 14 corresponds to the length of the boundary between zone Z1 and the second to fourth zones Z in the surface direction of electrostatic chuck 118.
[0064] In this embodiment, the weighting coefficient w between non-adjacent zones Z is regarded as 0. This makes it possible to reduce the amount of calculation by the model data creation unit 231. ij is uniquely determined once the arrangement of each zone Z is determined. Therefore, in this embodiment, the weighting coefficient w ij is calculated in advance and stored in the storage unit 24 before the processing illustrated in FIG.
[0065] Furthermore, in this embodiment, the weighting coefficients w are positive values whose sum is 1. This makes it possible to suppress the influence of multicollinearity when identifying coefficients in a regression model, and to identify coefficients in the regression model with high accuracy.
[0066] Next, the model data creation unit 231 calculates the coefficient a of the ARX model expressed in (1) above. i ~f iStep S104 is an example of step c). In step S104, the temperature control data is used to train an ARX model by a regression algorithm, and the coefficient a of the ARX model is determined. i ~f i The coefficients of the regression model are determined using a regression algorithm such as, for example, Ordinary Least Squares regression (OLS), Lasso, Ridge, or ElasticNet.
[0067] Next, the model data creation unit 231 calculates the weighting coefficient w ij Depending on the coefficient b i to each zone Z other than the i-th zone (S105). In step S105, the coefficient b i b i w ij It becomes.
[0068] Next, the model data creation unit 231 calculates the weighting coefficient w ij The coefficient b assigned to each zone Z other than the i-th zone according to i to the elements of the matrix (S106). Steps S105 and S106 are an example of the process d).
[0069] Then, the model data creation unit 231 determines whether or not the value of the variable i has reached the value of the constant n indicating the number of zones Z (S107). If the value of the variable i has not reached the value of the constant n (S107: No), the model data creation unit 231 increments the value of the variable i by 1 (S108) and executes the process shown in step S102 again.
[0070] On the other hand, if the value of the variable i reaches the value of the constant n (S107: Yes), the model data creation unit 231 transmits the model data including the matrix to which the elements have been added in step S106 to the substrate processing apparatus 10 via the communication I / F 21 (S109). Then, the model data creation apparatus 20 ends the process shown in this flowchart.
[0071] The model data transmitted to the substrate processing apparatus 10 in step S109 is expressed, for example, as in the following equation (3): The model data in this embodiment is an example of a multi-input multi-output state space model.
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[0072] In the above formula (3), the matrix x(t+1) is expressed, for example, as in the following formula (4).
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[0073] Moreover, in the above formula (3), the matrix A is expressed, for example, as in the following formula (5).
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[0074] In addition, in the above formula (3), the matrix B is expressed, for example, as in the following formula (6).
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[0075] In addition, in the above formula (3), the matrix C is expressed, for example, as in the following formula (7).
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[0076] [Processing in the substrate processing apparatus 10] Fig. 10 is a flow chart showing an example of a process of the substrate processing apparatus 10. The process shown in Fig. 10 is realized by the control unit 103 of the control device 100 reading a program from the storage unit 104 and executing the read program. The process shown in Fig. 10 is an example of step e).
[0077] First, the data collecting unit 1030 judges whether or not the model data creating device 20 has instructed the data collecting unit 1030 to create temperature control data via the communication I / F 101 (S200). If the data collecting unit 1030 has instructed the data collecting unit 1030 to create temperature control data (S200: Yes), the data collecting unit 1030 sets processing conditions and measures the temperature of each zone Z (S201). In step S201, the data collecting unit 1030 controls the device body 110 and collects data on the resistance value of the heater HT provided in each zone Z under a plurality of processing conditions. Then, the data collecting unit 1030 refers to the correspondence table 1040 in the storage unit 104 and identifies the temperature corresponding to the collected resistance value. Then, the data collecting unit 1030 creates temperature control data including the temperature data of each zone Z for each processing condition.
[0078] Next, the data collecting unit 1030 transmits the temperature control data created in step S201 to the model data creating device 20 via the communication I / F 101 (S202). Then, the process shown in step S200 is executed again.
[0079] On the other hand, if the creation of temperature control data has not been instructed (S200: No), the temperature control unit 1031 determines whether or not model data has been received from the model data creation device 20 via the communication I / F 101 (S203). If model data has been received (S203: Yes), the temperature control unit 1031 stores the received model data in the storage unit 104 (S204). Then, the process shown in step S200 is executed again.
[0080] On the other hand, if the model data has not been received (S203: No), the temperature control unit 1031 and the recipe execution unit 1032 determine whether or not an instruction to execute a recipe has been given by a user of the substrate processing apparatus 10 via the user I / F 102 (S205). If an instruction to execute a recipe has been given (S205: Yes), the temperature control unit 1031 uses the model data 1041 in the storage unit 104 to specify the power supplied to the heater HT provided in each zone Z as the manipulated variable (S206).
[0081] In step S206, the temperature control unit 1031 specifies the temperature of each zone Z that will result in a temperature distribution specified by the recipe 1042 in the storage unit 104. Then, the temperature control unit 1031 specifies the power to be supplied to the heater HT of each zone Z as a manipulated variable using the model data 1041 in the storage unit 104, with the specified temperature as a target value. The temperature control unit 1031 specifies the power to be supplied to the heater HT of each zone Z using the model data 1041, for example, by a method such as an optimal regulator or model predictive control. Then, the temperature control unit 1031 controls the switch SW2 of the corresponding heater control circuit 160 so that the specified power is supplied to each heater HT.
[0082] Next, the recipe execution unit 1032 controls each unit of the apparatus main body 110 in accordance with the recipe 1042 to process the substrate W (S207).
[0083] On the other hand, if execution of the recipe has not been instructed (S205: No), the recipe execution unit 1032 determines whether or not to end the process (S208). If the process is not to be ended (S208: No), the process shown in step S200 is executed again. On the other hand, if the process is to be ended by an instruction from the user of the substrate processing apparatus 10 via the user I / F 102 (S208: Yes), the process shown in this flowchart ends.
[0084] [Simulation results] Here, the advantages of the temperature control method in this embodiment will be described. Fig. 11 is a diagram showing an example of temperature change in each zone Z in temperature control in the comparative example. In the comparative example, the power supplied to the heater HT in each zone Z was controlled by PID. Fig. 11 shows temperature changes in four zones (Z1, Z6, Z10, and Z13) among the multiple zones Z, in which the temperature difference became relatively large as shown in Fig. 12. In the example of Fig. 11, the temperature of each zone Z was controlled to be 90°C.
[0085] 11, when the temperature of each zone Z is controlled individually by PID, the temperature of each zone Z is not yet sufficiently stable 200 msec after the start of control. Also, in the comparative example of FIG. 11, even in the process in which the temperature of each zone Z changes, there is a large difference in the rate of change of the temperature of each zone Z, and the temperature difference between each zone Z is large. Therefore, if processing of the substrate W is started before the temperature of the substrate W stabilizes at the target temperature, the temperature distribution of the substrate W varies greatly, and the uniformity of processing of the substrate W may be deteriorated.
[0086] In contrast, when the model-based temperature control method according to this embodiment is used, the temperature change in each zone Z is, for example, as shown in Fig. 13. Fig. 13 is a diagram showing an example of the temperature change in each zone Z in the temperature control of this embodiment. Fig. 13 also shows the temperature changes in the four zones (Z1, Z6, Z10, and Z13) shown in Fig. 12, but since the temperature changes in each zone Z are almost the same, the trajectories of the temperature changes almost overlap.
[0087] As shown in FIG. 13, when the temperature of each zone Z is controlled at 4° C. / sec by the model-based control in this embodiment, the temperature of each zone Z can be sufficiently stabilized at the target temperature in 200 msec from the start of control. Therefore, according to the temperature control method of this embodiment, the temperature distribution of the electrostatic chuck 118 and the edge ring ER can be more quickly brought closer to the target temperature distribution. In addition, in the example of FIG. 13, even in the process in which the temperature of each zone Z changes, the difference in the rate of change of the temperature of each zone Z is small, and the temperature difference between each zone Z is small. Therefore, even if the processing of the substrate W is started before the temperature of the substrate W is stabilized at the target temperature, the variation in the temperature distribution of the substrate W is small, and the uniformity of the processing of the substrate W can be improved. Note that, as shown in FIG. 13, it is also possible to realize a temperature change with an arbitrary gradient, such as 3° C. / sec and 2° C. / sec, by precisely specifying the temperature on the way to the final target temperature as the target temperature.
[0088] The first embodiment has been described above. As described above, the model-based control method in this embodiment includes steps a), b), c), d), and e). In step a), temperature control data including data on the temperature of each zone Z in a temperature control member provided in the substrate processing apparatus 10 and having a plurality of zones Z whose temperatures can be controlled individually is acquired. In step b), for each zone Z, the temperature of the other zones Z weighted and averaged by a weighting coefficient w determined according to the magnitude of heat transfer between the other zones Z is identified. In step c), parameters of a multi-input single-output state space model are identified for each zone Z using the identified temperatures of the other zones and the temperature control data. In step d), model data is created by assigning the identified parameters of the multi-input single-output state space model to each element of model data, which is an example of a multi-input multi-output state space model. In step e), the model data is used to control the temperature of each zone Z of the temperature control member. This allows the temperature distribution of the temperature control member to approach a target temperature distribution more quickly.
[0089] Here, when controlling the temperature distribution of the stage, the temperature of each zone of the stage is affected by the temperature of the other zones. Therefore, when individually estimating the effect of thermal interference that the temperature of each zone has on the temperature of the adjacent zone, experimental data in which temperature control was performed with a huge number of combinations is required, which is not feasible. In contrast, the model-based control method of this embodiment estimates the temperature of each zone using a regression model, so that the temperature of each zone can be accurately controlled even with a small amount of experimental data.
[0090] In the above embodiment, the weighting coefficient w of each zone Z is determined based on the area of the boundary surface with other adjacent zones Z or the length of the boundary, and the weighting coefficient w for other non-adjacent zones Z is 0. Here, as the number of zones increases, the number of parameters that can be included in the explanatory variables increases, but it is necessary to exclude parameters that are not related to each other. In the above embodiment, the weighting coefficient w for other non-adjacent zones Z is set to 0, so that the number of explanatory variables can be reduced. This makes it possible to reduce the amount of calculation required when creating model data.
[0091] In the above embodiment, the temperature control member is the stage 116 on which the substrate W is placed and which controls the temperature of the substrate W. This allows the temperature distribution of the substrate W during processing to more quickly approach the target temperature distribution.
[0092] Furthermore, in the above embodiment, the multi-input multi-output state space model includes a term indicating the temperature of the refrigerant controlled by the chiller unit that cools the multiple zones Z, and a term indicating the magnitude of the power supply voltage supplied to the heater HT that heats the multiple zones Z. This makes it possible to perform reproducible control even when there are changes in the refrigerant temperature and power supply voltage, and to perform control along a specified temperature change trajectory.
[0093] In the above embodiment, the state space model with multiple inputs and single outputs is an ARX model, which allows the state of a temperature control member having multiple zones Z to be modeled with high accuracy.
[0094] In the above embodiment, the parameters of the multi-input single-output state space model are determined using OLS, Lasso, Ridge, or Elastic Net. This allows the coefficients of the regression model to be determined with high accuracy. In particular, the use of Lasso, Ridge, or Elastic Net makes it possible to suppress overlearning.
[0095] In the above embodiment, at least one of the multiple zones is different from the adjacent zones in at least one of the zone shape, boundary surface shape, and material. If the adjacent conditions between the adjacent zones are different, the weight coefficients between the adjacent zones are different, making it even more difficult to prepare experimental data. In contrast, in this embodiment, by using a multi-input multi-output state space model, the temperatures of multiple zones can be accurately estimated with a small amount of experimental data even if the adjacent conditions between the adjacent zones are different.
[0096] Also, in the above embodiment, temperature control data including the temperature of each zone is acquired via a substrate placed on the temperature control member.
[0097] In the above embodiment, the weighting coefficients are positive values whose sum is 1. When modeling is performed using data obtained by simultaneously controlling the temperature of a plurality of zones, a high correlation occurs between the zones, and the coefficients of the model are not determined correctly due to the influence of multicollinearity. In contrast, in the model-based control method of the present embodiment, modeling is performed using weighting coefficients whose sum is 1. This makes it possible to prevent the correlation between the zones Z in terms of temperature from becoming excessively high, and to suppress the influence of multicollinearity.
[0098] The substrate processing system 1 in the above embodiment is a model-based control system, and includes a substrate processing apparatus 10 and a model data creating device 20. The model data creating device 20 includes a control unit 23 configured to create a state space model, and a communication I / F 21 configured to output the state space model to the substrate processing apparatus 10. The substrate processing apparatus 10 includes a temperature control member configured to have a plurality of zones Z whose temperatures can be controlled individually, a storage unit 104 configured to acquire and store the state space model created by the model data creating device 20, and a control unit 103 configured to control the temperature of each zone Z of the temperature control member using the state space model stored in the storage unit 104. The control unit 23 of the model data creating device 20 executes steps a), b), c), and d). In step a), temperature control data including data on the temperature of each zone Z measured in the temperature control member is acquired. In step b), the weighted average temperature of the other zones Z is identified using a weighting coefficient w determined according to the magnitude of heat transfer between each zone Z and the other zones Z, the weighting coefficient w being a positive weighting coefficient whose sum is 1. In step c), a regression model using the identified temperatures of the other zones Z is trained using temperature control data for each zone Z, and coefficients of the regression model are identified. In step d), model data is created by assigning the identified coefficients of the regression model to each element of model data, which is an example of a multi-input, multi-output state space model. High control performance is achieved by creating model data and using the model-based control. This allows the substrate processing apparatus 10 to more quickly bring the temperature distribution of the temperature control member closer to the target temperature distribution.
[0099] The program in the above-described embodiment is a program that causes a computer to execute steps a), b), c), and d). In step a), temperature control data is acquired, including data on the temperature of each zone Z, measured in a temperature control member provided in the substrate processing apparatus 10 and having a plurality of zones Z each capable of being individually temperature-controlled. In step b), a weighted average temperature of the other zones Z is identified for each zone Z using a weighting coefficient w determined according to the magnitude of heat transfer between the zones Z and the other zones Z, the weighting coefficient w being a positive weighting coefficient w whose sum is 1. In step c), a regression model using the identified temperatures of the other zones Z is trained using the temperature control data for each zone Z, and coefficients of the regression model are identified. In step d), model data is created by assigning the coefficients of the identified regression model to each element of model data, which is an example of a multi-input multi-output state space model. The substrate processing apparatus 10 can more quickly bring the temperature distribution of the temperature control member closer to a target temperature distribution by controlling the temperature distribution of the temperature control member using the model data created by the computer.
[0100] Second embodiment In the second embodiment, the temperature distribution of each zone Z after temperature control is performed using the model data during operation of the substrate processing apparatus 10 is measured, and the coefficients of the model data are updated based on the measurement results. This allows the model data to be corrected in accordance with the characteristics of the actual substrate processing apparatus 10, improving the accuracy of temperature control. In addition, since the coefficients of the model data are corrected following the aging of the substrate processing apparatus 10 due to wear and tear of parts, etc., it is possible to suppress deterioration in the accuracy of the control of the temperature distribution of each zone Z associated with the aging of the substrate processing apparatus 10. The following mainly describes the points that are different from the first embodiment.
[0101] 14 is a diagram showing an example of the control device 100 included in the substrate processing apparatus 10 according to the second embodiment. In this embodiment, the control unit 103 executes a program stored in the storage unit 104 to further realize the function of a model data update unit 1033. The model data update unit 1033 updates the coefficients of the model data by adaptive control. The adaptive control is a control that removes model errors by updating a model based on the residual between a predicted value and an actual measurement value while the actual device is operating.
[0102] 15 is a diagram showing an example of a procedure for updating the coefficients of the model data. First, the recipe execution unit 1032 outputs a target temperature defined in the recipe 1042 in the storage unit 104 to the temperature control unit 1031. The temperature control unit 1031 specifies the power supplied to the heater HT of each zone Z as a manipulated variable using the model data 1041 in the storage unit 104. Then, the temperature control unit 1031 controls the switch SW2 of the heater control circuit 160 according to the specified manipulated variable for each heater HT. The temperature control unit 1031 outputs a predicted value of the temperature for the manipulated variable for each zone Z to the model data update unit 1033.
[0103] The model data update unit 1033 collects data on the resistance value of the heater HT in each zone Z. Then, the model data update unit 1033 refers to the correspondence table 1040 in the storage unit 104, and specifies the temperature corresponding to the resistance value collected for each zone Z as an actual measurement value. The step of specifying the actual measurement value of the temperature for each zone Z is an example of step f). Then, the model data update unit 1033 calculates, for each zone Z, the difference between the specified actual measurement value and the predicted value output from the temperature control unit 1031 as a prediction error. Then, the model data update unit 1033 specifies the coefficients of the updated model data, for example, by using the following equations (8) to (11).
number
number
number
number
[0104] The definitions of the symbols in the above formulas (8) to (11) are as follows:
number
[0105] Then, the model data update unit 1033 updates the coefficients of the model data 1041 in the storage unit 104 with the identified coefficients. The process of updating the coefficients of the model data 1041 is an example of step g). The temperature control unit 1031 identifies the power to be supplied to the heater HT of each zone Z using the model data 1041 with the updated coefficients.
[0106] [Experimental Results] Fig. 16 is a diagram showing an example of the effect of adaptive control. Similar to the simulations of Figs. 11 and 13, Fig. 16 shows temperature changes in four zones (Z1, Z6, Z10, and Z13: see Fig. 12) in which the temperature difference between zones Z becomes relatively large. As shown in Fig. 16, by performing adaptive control, it is possible to suppress the temperature difference between zones Z to less than ±0.2°C compared to the case where adaptive control is not performed. This makes it possible to improve the accuracy of temperature distribution control.
[0107] [Operation of model data using adaptive control] 17 is a flowchart showing an example of a procedure for managing model data using adaptive control. First, reference model data is generated using temperature control data of a plurality of reference substrate processing apparatuses 10 (S300).
[0108] Next, at the mass production site of the substrate processing apparatus 10, a test operation is performed using the reference model data in the substrate processing apparatus 10 before shipment, and the reference model data is updated by adaptive control (S301).
[0109] Next, the updated reference model data is stored as individual model data in the storage unit 104 of the substrate processing apparatus 10 before shipment (S302).
[0110] Next, after the substrate processing apparatus 10 is shipped, the individual model data is used for operation at the manufacturing site of the substrate W, and the individual model data is updated by adaptive control (S303). In step S303, the individual model data before the update is stored in the storage unit 104 separately from the updated individual model data.
[0111] Then, when the operation of the substrate processing apparatus 10 is terminated, the updated individual model data is discarded (S304). Then, when the operation of the substrate processing apparatus 10 is resumed, the process shown in step S303 is executed again.
[0112] In this manner, in this embodiment, each time operation is terminated, the updated individual model data is restored to the individual model data saved at the time of shipment. This makes it possible to prevent deterioration of control performance when the next temperature condition changes significantly due to adaptation to the previous temperature setting by adaptive control. Note that, in order to adapt to part wear, it is possible to execute a program for adaptive control and update the individual model data.
[0113] The second embodiment has been described above. As described above, the model-based control method in this embodiment further includes steps f) and g). In step f), data on the temperature of each zone Z measured during operation of the substrate processing apparatus 10 is acquired. In step g), the coefficients of each element of the state space model are updated by adaptive control based on the error between the temperature predicted using the state space model and the temperature acquired in step f). This makes it possible to reduce the error between the behavior of the actual temperature control member (electrostatic chuck 118 and edge ring ER) and the behavior of the multi-input multi-output state space model. This makes it possible to reduce the influence of individual differences in the temperature control member on the model error. In addition, it becomes possible to update the model due to errors during actual operation.
[0114] (Third embodiment) In the first and second embodiments described above, it is assumed that each zone Z of the temperature control member is made of the same material. In contrast, in this embodiment, when the zone Z of the temperature control member includes a zone Z made of a material different from that of the other zones Z, the ARX model is expressed using a weighting coefficient w according to the magnitude of thermal conduction between the zones Z made of different materials.
[0115] For example, as shown in FIG. 18, zones Z1 to Z3 have a thermal conductivity λ A The zone Z4 is made of material A with thermal conductivity λ B Consider the case where the zone Z1 is formed of material B. In the example of Fig. 18, zones Z2 to Z4 are adjacent to the periphery of zone Z1, and the area of the boundary surface between zone Z1 and zones Z2 to Z4 is the same. Also, in the example of Fig. 18, the thickness of the boundary surface between zone Z1 and zones Z2 to Z4 is the same.
[0116] If the materials of zones Z1 to Z4 are the same, the weighting factor w 12 =w 13 =w 14 = 1 / 3, but since the materials of zones Z1 to Z3 and zone Z4 are different, the weighting coefficient is corrected as shown in the following formula (13).
number
[0117] The third embodiment has been described above. As described above, in the model-based control method in this embodiment, the weighting coefficient of each zone Z is determined based on the magnitude of thermal conduction caused by the difference between the material of the zone Z and the material of other zones Z adjacent to the zone Z. As a result, even if the zones Z of the temperature control member include a zone Z made of a material different from the material of the other zones Z, a weight according to the actual magnitude of thermal conduction between the zones Z can be assigned.
[0118] [others] It should be noted that the technology disclosed in the present application is not limited to the above-described embodiment, and various modifications are possible within the scope of the gist thereof.
[0119] For example, in each of the above-described embodiments, a weighting coefficient w is defined between adjacent zones Z, and the weighting coefficient w is considered to be 0 between non-adjacent zones Z, but the disclosed technology is not limited to this. As another embodiment, a weighting coefficient w may also be assigned between non-adjacent zones Z. The weighting coefficient between non-adjacent zones Z may be determined taking into consideration, for example, the distance between the zones Z and the material of the member interposed between the zones Z.
[0120] In addition, in each of the above-described embodiments, one heater HT is provided in each zone Z, and the temperature of the corresponding zone Z is estimated based on the resistance value of the heater HT, but the disclosed technology is not limited to this. As another embodiment, a temperature sensor for measuring the temperature of the zone Z may be provided for each zone Z. In this case, the distance between the measurement point of the temperature of the zone Z and other zones, and the distance between the measurement point of the temperature of the zone Z and the heating point where the heater HT is provided may be incorporated into the model data as a weight. In addition, when multiple temperature sensors are provided for each zone Z, the distance between the measurement point of the temperature of the zone Z and other zones, and the distance between the measurement point of the temperature of the zone Z and the heating point where the heater HT is provided may be incorporated into the model data as a weight for each measurement point.
[0121] In addition, in each of the above-described embodiments, the electrostatic chuck 118 and the edge ring ER have been described as examples of temperature control members, but the disclosed technology is not limited to this. Members having multiple zones Z whose temperatures can be individually controlled may be members other than the electrostatic chuck 118 and the edge ring ER (for example, the electrode plate 134 of the upper electrode 130, the side wall of the processing vessel 112, etc.).
[0122] In addition, the ARX model in each of the above-mentioned embodiments includes the power supply voltage v(t) and chiller temperature z(t) of the heater HT as explanatory variables, but the disclosed technology is not limited to this. When the power supply voltage v(t) and chiller temperature z(t) are not changed during operation of the substrate processing apparatus 10, the ARX model does not need to include the power supply voltage v(t) and chiller temperature z(t) as explanatory variables. In other forms, the frequency of the RF power, the magnitude of the RF power, the pressure inside the processing vessel 112, the type of gas supplied into the processing vessel 112, the flow rate of the gas supplied into the processing vessel 112, etc. may be added as explanatory variables.
[0123] It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be construed as limiting. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims. [Explanation of symbols]
[0124] E1 electrode ER Edge Ring HFS RF power supply HT Heater LFS RF power supply MU matching box N Communication Network S Processing space SW Switch W substrate Z-Zone 1. Substrate Processing System 10 Substrate processing equipment 100 Control device 101 Communication I / F 102 User Interface 103 Control section 1030 Data Collection Department 1031 Temperature control unit 1032 Recipe Execution Unit 1033 Model Data Update Section 104 Storage section 1040 Compatibility Chart 1041 Model Data 1042 Recipes 110 Device body 112 Processing vessel 112a Grounding conductor 112e Exhaust port 112g opening 116 Stages 114 Support part 118 Electrostatic Chuck 120 Foundation 122 DC power supply 124 Flow Path 126 Piping 130 Upper electrode 132 Insulating shielding material 134 Electrode plate 134a Gas outlet 136 Support 136a Gas diffusion chamber 136b Gas distribution port 136c Gas inlet 138 Piping 140 Gas Source Group 142 Valve Group 144 Flow Controller Group 146 Depot Shield 148 Exhaust plate 150 Exhaust system 152 Exhaust pipe 154 Gate valve 160 Heater control circuit 161 Control Blocks 163 Ammeter 164 Voltmeter 165 Measuring section 166 Power supply 20 Model data creation device 21 Communication I / F 22 User Interface 23 Control Unit 230 Data Collection Department 231 Model Data Creation Department 24 Memory section 240 Temperature Control Data 241 Weighting Factor
Claims
1. a) acquiring temperature control data including data on temperatures of each of a plurality of zones in a temperature control member provided in a processing device and having the plurality of zones whose temperatures can be individually controlled; b) determining, for each of the zones, the temperature of the other zones weighted by a weighting factor determined according to the magnitude of heat transfer between the zones and the other zones; c) for each of the zones, identifying parameters of a multi-input, single-output state space model using the identified temperatures of the other zones and the temperature control data; d) creating a multiple-input, multiple-output state space model by assigning the identified parameters of the multiple-input, single-output state space model to each element of the multiple-input, multiple-output state space model; e) controlling the temperature of each of the zones of the temperature control member using the multiple-input, multiple-output state space model; A model-based control method comprising:
2. f) acquiring temperature data for each of said zones measured during operation of said treatment apparatus; g) updating parameters of each element of the multi-input / multi-output state space model by adaptive control based on an error between a temperature predicted using the multi-input / multi-output state space model and the temperature acquired in step f); The method of claim 1 , further comprising:
3. The weighting factor of each of the zones is determined based on the area or length of a boundary surface between the zones and adjacent zones; 3. The model-based control method according to claim 1, wherein the weighting factor for other non-adjacent zones is zero.
4. 3. The model-based control method according to claim 1, wherein the weighting coefficient for each of the zones is determined based on the magnitude of heat transfer resulting from a difference between a material of the zone and a material of another zone adjacent to the zone.
5. the processing apparatus is a substrate processing apparatus for processing a substrate, The model-based control method according to claim 1 , wherein the temperature control member is a stage on which a substrate is placed and controls a temperature of the substrate.
6. 6. The model-based control method according to claim 1, wherein the multi-input, multi-output state space model includes a term indicating a temperature of a refrigerant controlled by a chiller unit that cools the multiple zones, and a term indicating a magnitude of a power supply voltage supplied to a heater that heats the multiple zones.
7. The model-based control method according to claim 1 , wherein the state space model with multiple inputs and single outputs is an auto-regressive eXogenous (ARX) model.
8. 8. The model-based control method according to claim 1, wherein in the step c), parameters of the multi-input single-output state space model are identified using Ordinary Least Squares regression (OLS), Lasso, Ridge, or ElasticNet.
9. The model-based control method according to claim 1 , wherein at least one of the plurality of zones is different from adjacent zones in at least one of the zone shape, boundary surface shape, and material.
10. the processing apparatus is a substrate processing apparatus for processing a substrate, 10. The method of claim 1, wherein the temperature control data including the temperature of each of the zones is obtained via a substrate mounted on the temperature control member.
11. A model data generating device and a processing device are provided, The model data creation device includes: a first controller configured to generate a state space model; an output section configured to output the state space model to the processing device; having The processing device includes: A temperature control member configured to have a plurality of zones each having a temperature that can be individually controlled; a storage unit configured to acquire and store the state space model created by the model data creation device; a second controller configured to control a temperature of each of the zones of the temperature control member using the state space model stored in the memory; having The first control unit is a) acquiring temperature control data including data on the temperature of each of said zones in said temperature control member; b) determining, for each of the zones, the temperature of the other zones weighted by a weighting factor determined according to the magnitude of heat transfer between the zones and the other zones; c) for each of the zones, identifying parameters of a multi-input, single-output state space model using the identified temperatures of the other zones and the temperature control data; d) creating a multi-input / multi-output state space model by assigning the identified parameters of the multi-input / single-output state space model to each element of the multi-input / multi-output state space model; A model-based control system that performs
12. The second control unit is e) controlling the temperature of each of the zones of the temperature control member using the multi-input, multi-output state space model stored in the memory unit; f) acquiring temperature data for each of said zones measured during operation of said treatment apparatus; g) updating parameters of each element of the multi-input / multi-output state space model by adaptive control based on an error between a temperature predicted using the multi-input / multi-output state space model and the temperature acquired in step f); The model-based control system of claim 11 , further comprising:
13. a) acquiring temperature control data including data on temperatures of each of a plurality of zones in a temperature control member provided in a processing device and having the plurality of zones whose temperatures can be individually controlled; b) determining, for each of the zones, the temperature of the other zones weighted by a weighting factor determined according to the magnitude of heat transfer between the zones and the other zones; c) for each of the zones, identifying parameters of a multi-input, single-output state space model using the identified temperatures of the other zones and the temperature control data; d) creating a multi-input / multi-output state space model by assigning the identified parameters of the multi-input / single-output state space model to each element of the multi-input / multi-output state space model; A program that causes a computer to execute the following.
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