Substrate processing device and substrate temperature control method

Abstract

An acquisition unit according to the present invention periodically acquires: the temperature of a stage on which a substrate is placed; the temperature of a cooling mechanism which is provided on the stage and which cools the stage; and a heat generation amount of a heating mechanism that is provided between the cooling mechanism and a placement surface of the stage on which the substrate is placed and that heats the stage. A prediction unit uses a calculation formula which predicts the temperature of the substrate from the heat generation amount of the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time derivative of the temperature of the stage, and the time derivative of the temperature of the cooling mechanism, so as to predict the temperature of the substrate from the heat generation amount of the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time derivative of the temperature of the stage, and the time derivative of the temperature of the cooling mechanism which have been acquired from the acquisition unit. A heat generation control unit controls the heat generation amount of the heating mechanism such that the temperature of the substrate predicted by the prediction unit becomes a prescribed temperature.

Description

Substrate processing apparatus and substrate temperature control method

[0001] The present disclosure relates to a substrate processing apparatus and a substrate temperature control method.

[0002] JP-A-2003-129999 discloses a plasma processing apparatus including: a processing chamber whose interior is evacuated to a reduced pressure; a sample stage provided in the processing chamber and having a sample mounting surface on which a substrate to be processed is placed; a plasma generating device for generating plasma in the processing chamber; a heat transfer gas supply system for supplying a gas for heat transfer to the sample mounting surface; and a coolant passage provided in the sample stage through which a coolant circulates; the sample stage has a heater layer provided between the sample mounting surface and the coolant passage, and the heater layer is divided into a plurality of regions in a radial direction of the sample mounting surface; temperature monitors provided in the sample stage near the heater layer and at positions corresponding to each divided region of the heater layer; and a temperature control device that estimates temperatures at positions corresponding to each divided region of the substrate to be processed placed on the sample mounting surface based on temperature information from each temperature monitor, and controls power supply to the heater layer in each divided region in accordance with the estimated temperature values.

[0003] JP 2008-177285 A

[0004] The present disclosure provides techniques for accurately controlling the temperature of a substrate.

[0005] A substrate processing apparatus according to one aspect of the present disclosure includes a stage, a chamber, a cooling mechanism, a heating mechanism, a measurement unit, an acquisition unit, a prediction unit, and a heat generation control unit. The stage is configured to receive a substrate. The chamber includes a stage mounted therein, and a heat source that inputs heat to the substrate mounted on the stage is provided. The cooling mechanism is configured to cool the stage. The heating mechanism is configured between the stage mounting surface on which the substrate is mounted and the cooling mechanism, and is capable of controlling the amount of heat generated, thereby heating the stage. The measurement unit measures the temperature of the stage. The acquisition unit periodically acquires the amount of heat generated by the heating mechanism, the temperature of the stage, and the temperature of the cooling mechanism. The prediction unit predicts the temperature of the substrate from the amount of heat generated by the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time derivative of the temperature of the stage, and the time derivative of the temperature of the cooling mechanism, all acquired by the acquisition unit, using a calculation formula for predicting the temperature of the substrate from the amount of heat generated by the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time derivative of the temperature of the stage, and the time derivative of the temperature of the cooling mechanism. The heat generation control unit controls the amount of heat generated by the heating mechanism so that the temperature of the substrate predicted by the prediction unit becomes a predetermined temperature.

[0006] According to the present disclosure, the temperature of the substrate can be controlled with high precision.

[0007] Fig. 1 is a diagram for explaining an example of the configuration of a capacitively coupled plasma processing apparatus. Fig. 2 is a plan view showing an example of the configuration of an electrostatic chuck according to an embodiment. Fig. 3 is a cross-sectional view showing an example of the configuration of an electrostatic chuck according to an embodiment. Fig. 4 is a block diagram showing a schematic configuration of a control unit according to an embodiment. Fig. 5 is a diagram showing an example of a thermal circuit representing a substrate and a main body according to an embodiment. Fig. 6 is a flowchart showing an example of the flow of a substrate temperature control process according to an embodiment.

[0008] Hereinafter, embodiments of the substrate processing apparatus and the substrate temperature control method disclosed in the present application will be described in detail with reference to the drawings. However, the substrate processing apparatus and the substrate temperature control method disclosed are not limited to the embodiments.

[0009] There are known substrate processing apparatuses that perform heat treatments such as plasma processing and ashing on substrates such as semiconductor wafers (hereinafter also referred to as "wafers"), etc. Some of these substrate processing apparatuses are provided with a heater on a mounting section for mounting the substrate and a flow path through which a coolant flows, and control the temperature of the mounting section by heating with the heater and cooling with the coolant flowing through the flow path, thereby controlling the temperature of the substrate.

[0010] However, in a substrate processing apparatus, heat is input to the substrate from heat sources such as plasma and heated components in the chamber, and it may not be possible to accurately control the temperature of the substrate.

[0011] Therefore, in substrate processing apparatuses, a technique for controlling the temperature of the substrate with high precision is desired.

[0012] [Embodiment] [Apparatus Configuration] An example of a substrate processing apparatus according to the present disclosure will be described. In the embodiment described below, the substrate processing apparatus according to the present disclosure will be described as a plasma processing system having a system configuration for performing plasma processing.

[0013] An example of the configuration of a plasma processing system will be described below: Fig. 1 is a diagram for explaining an example of the configuration of a capacitively coupled plasma processing apparatus.

[0014] The plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a controller 100. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 has at least one gas inlet for supplying at least one processing gas to the plasma processing space 10s and at least one gas outlet for exhausting gas from the plasma processing space 10s. The plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0015] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region 111a for supporting a substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. Therefore, the central region 111a is also called a substrate support surface for supporting the substrate W, and the annular region 111b is also called a ring support surface for supporting the ring assembly 112.

[0016] In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 can function as a lower electrode. The electrostatic chuck 1111 is disposed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Note that the annular region 111b may also be provided by another member surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. Furthermore, at least one RF / DC electrode coupled to an RF (Radio Frequency) power supply 31 and / or a DC (Direct Current) power supply 32 (described later) may be disposed within the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or a DC signal (described later) is supplied to the at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as multiple lower electrodes. Furthermore, the electrostatic electrode 1111b may function as a lower electrode. Therefore, the substrate support 11 includes at least one lower electrode.

[0017] The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one cover ring. The edge rings are formed of a conductive or insulating material, and the cover rings are formed of an insulating material.

[0018] The substrate support 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow path 1110a, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path 1110a. In one embodiment, the flow path 1110a is formed in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. The flow path 1110a has pipes 14a connected to both ends and is connected to the chiller unit 14 via the pipes 14a. The chiller unit 14 stores a coolant, such as brine, and supplies the stored coolant to one of the pipes 14a. The coolant supplied from the chiller unit 14 is supplied to the flow path 1110a via one pipe 14a, flows from one end of the flow path 1110a to the other end, and returns to the chiller unit 14 via the other pipe 14a. The chiller unit 14 is configured to be able to change the temperature of the coolant stored therein. The chiller unit 14 also has a built-in temperature sensor that can measure the temperature of the coolant being supplied. The chiller unit 14 changes the temperature of the coolant stored therein under control of the control unit 100. The chiller unit 14 also outputs the coolant temperature measured by the temperature sensor to the control unit 100. The plasma processing apparatus 1 is configured to be able to control the temperature of the main body 111 by circulating the temperature-controlled coolant from the chiller unit 14 through the flow path 1110a to cool the coolant while heating it with a heater. In the embodiment, the main body 111 corresponds to the stage of the present disclosure. In the embodiment, the central region 111a corresponds to the mounting surface of the present disclosure. In addition, in the embodiment, the coolant, the flow path 1110a, etc. correspond to the cooling mechanism of the present disclosure.

[0019] Here, the configuration of the electrostatic chuck 1111 of the substrate support part 11 will be described. Fig. 2 is a plan view showing an example of the configuration of the electrostatic chuck 1111 according to the embodiment. Fig. 3 is a cross-sectional view showing an example of the configuration of the electrostatic chuck 1111 according to the embodiment.

[0020] 2 shows a plan view of the upper surface of the electrostatic chuck 1111. The upper surface of the electrostatic chuck 1111 is divided into a central region 111a and an annular region 111b. The central region 111a is a region that is approximately circular in plan view. A substrate W is placed on the upper surface of the central region 111a. The diameter of the central region 111a is approximately the same as that of the substrate W or is slightly smaller than the diameter of the substrate W. The annular region 111b is a region that surrounds the central region 111a and extends in a substantially annular shape. In one embodiment, the upper surface of the annular region 111b is located at a lower position than the upper surface of the central region 111a.

[0021] The central region 111a is divided into multiple areas A1 to A14. Hereinafter, the areas A1 to A14 will be referred to collectively as area A when they are not distinguished from one another. Each area A is a division of the central region 111a and constitutes a part of the central region 111a. For example, as shown in FIG. 2, the central region 111a is divided into a circular area A1 at its center. The central region 111a is further divided into multiple concentric annular regions from the circular area A1, and each of the multiple annular regions is divided circumferentially into multiple arc-shaped areas A2 to A14. The arc-shaped areas A2 to A14 have smaller angular widths closer to the periphery. The flow path 1110a is formed within the base 1110 so as to pass under all of the areas A. Note that the method of dividing the areas A shown in FIG. 2 is merely an example and is not limited thereto. For example, the central region 111a may be divided so that the radial width of the arc-shaped area A narrows toward the outer periphery. The central region 111a may also be divided into areas A, each of which is concentrically spaced at a fixed angle from the center. The central region 111a may also be divided into areas A in a lattice pattern. To precisely control the temperature distribution in the central region 111a, the central region 111a may be divided into more areas A. For example, the central region 111a may be divided into 100 or more areas A. While the division method for areas A shown in FIG. 2 illustrates a case in which the annular region 111b is not divided, this is not limiting. The annular region 111b may also be divided into multiple areas A. For example, the annular region 111b may be divided into multiple arc-shaped areas A in the circumferential direction.

[0022] The electrostatic chuck 1111 has a heater HT and a temperature sensor TS provided in each area A. FIG. 3 schematically shows a partial cross section of two areas A of the electrostatic chuck 1111. An electrostatic electrode 1111b is disposed within the ceramic member 1111a. A heater HT and a temperature sensor TS are also disposed within the ceramic member 1111a for each area A. The heater HT generates heat when power is supplied to heat the area A. In the embodiment, the heater HT corresponds to the heating mechanism of the present disclosure. In the embodiment, the temperature sensor TS corresponds to the measurement unit of the present disclosure.

[0023] Returning to Fig. 1, each heater HT is connected to a heater power supply 60. Each temperature sensor TS is connected to a temperature detection unit 61. Note that Fig. 1 omits some of the wiring connecting each heater HT to the heater power supply 60 and each temperature sensor TS to the temperature detection unit 61.

[0024] The heater power supply 60 supplies power to each heater HT. The heater power supply 60 is capable of adjusting the power supplied to each heater HT. For example, the heater power supply 60 performs PWM (Pulse Width Modulation) control of the power supplied to each heater HT. PWM control controls the output power by periodically switching the heater on and off within one cycle. The heater power supply 60 is configured to supply a predetermined amount of power to each heater HT and controls the power supplied to each heater HT by changing the ratio of the on period (duty ratio) within one cycle. The heater power supply 60 adjusts the power supplied to each heater HT based on control data input from the control unit 100. The amount of heat generated by each heater HT can be controlled by PWM control of the power supplied. Each heater HT generates heat using the power supplied from the heater power supply 60 and heats the area A.

[0025] The temperature detection unit 61 measures the resistance value of each temperature sensor TS, and detects the temperature of each temperature sensor TS arranged in each area A based on the measured resistance value.

[0026] The temperature sensors TS may be made of a material whose resistance changes with temperature. For example, the temperature sensors TS may be thermistors. Alternatively, the temperature sensors TS may be thin films made of any of the following materials: tungsten, nickel, molybdenum, copper, silver, platinum, and aluminum. The temperature detection unit 61 may measure the current and voltage of the power supplied to each temperature sensor TS, calculate the resistance of each temperature sensor TS from the measured current and voltage, and detect the temperature of the main body 111 of each area A based on the calculated resistance.

[0027] The showerhead 13 is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The process gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the multiple gas inlets 13c. The showerhead 13 also includes at least one upper electrode. In addition to the showerhead 13, the gas inlet may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0028] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one process gas from a corresponding gas source 21 to the showerhead 13 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include one or more flow modulation devices to modulate or pulse the flow rate of the at least one process gas.

[0029] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power) to at least one lower electrode and / or at least one upper electrode. This generates a plasma from at least one process gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of a plasma generating unit configured to generate a plasma from one or more process gases in the plasma processing chamber 10. Furthermore, by supplying a bias RF signal to the at least one lower electrode, a bias potential is generated on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0030] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to at least one lower electrode and / or at least one upper electrode via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generating unit 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to at least one lower electrode and / or at least one upper electrode.

[0031] The second RF generator 31b is coupled to at least one lower electrode via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0032] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to the at least one lower electrode and configured to generate a first DC signal. The generated first bias DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to the at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the at least one upper electrode.

[0033] In various embodiments, at least one of the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generator for generating the sequence of voltage pulses from the DC signal is connected between the first DC generator 32a and at least one lower electrode. Thus, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. When the second DC generator 32b and the waveform generator constitute a voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulses may have either positive or negative polarity. Furthermore, the sequence of voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses within one period. The first and second DC generating units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided instead of the second RF generating unit 31b.

[0034] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is regulated by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0035] The operation of the plasma processing apparatus 1 configured as described above is controlled in an integrated manner by a control unit 100. The control unit 100 is, for example, a computer, and controls each unit of the plasma processing apparatus 1. The operation of the plasma processing apparatus 1 is controlled in an integrated manner by the control unit 100. The control unit 100 controls the plasma processing apparatus 1 to execute various processes described in this disclosure.

[0036] [Configuration of Control Unit] Next, the control unit 100 will be described. Fig. 4 is a block diagram showing a schematic configuration of the control unit 100 according to the embodiment. The control unit 100 includes an external interface 101, a user interface 102, a storage unit 103, and a process controller 104.

[0037] The external interface 101 is capable of communicating with each part of the plasma processing apparatus 1 and inputs and outputs various data. The user interface 102 is composed of a keyboard through which a process manager inputs commands to manage the plasma processing apparatus 1, a display that visualizes and displays the operating status of the plasma processing apparatus 1, and the like.

[0038] The storage unit 103 stores a control program (software) and various programs for implementing various processes executed in the plasma processing apparatus 1 under the control of the process controller 104. The storage unit 103 also stores various data used by the programs executed by the process controller 104. For example, the storage unit 103 stores a recipe in which processing condition data and the like are stored, and prediction model data 110. The programs and data may be stored in a computer-readable computer recording medium (e.g., a hard disk, an optical disk such as a DVD, a flexible disk, a semiconductor memory, etc.). The programs and data may also be transmitted as needed from another device, for example, via a dedicated line, for online use.

[0039] The prediction model data 110 is data storing a prediction model for predicting the temperature of the substrate W from the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the coolant, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the coolant. In this embodiment, the prediction model is a calculation formula for predicting the temperature of the substrate W in each area A from the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the coolant, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the coolant in each area A. Details of the prediction model will be described later.

[0040] The process controller 104 includes a processor, such as a CPU (Central Processing Unit) and an MPU (Micro Processing Unit), and controls each component of the plasma processing apparatus 1. The process controller 104 has an internal memory for storing programs and data, reads a control program stored in the storage unit 103, and executes the processing of the read control program. The process controller 104 functions as various processing units when the control program runs. For example, the process controller 104 has the functions of a plasma control unit 120, an acquisition unit 121, a correction unit 122, a prediction unit 123, and a heat generation control unit 124. Note that this embodiment describes an example in which the process controller 104 has the functions of the plasma control unit 120, the acquisition unit 121, the correction unit 122, the prediction unit 123, and the heat generation control unit 124. However, the functions of the plasma control unit 120, the acquisition unit 121, the correction unit 122, the prediction unit 123, and the heat generation control unit 124 may be distributed among multiple controllers.

[0041] The plasma control unit 120 controls each part of the plasma processing apparatus 1 and controls the plasma processing.

[0042] The acquisition unit 121 periodically acquires the heat generation amount of each heater HT, the temperature of the main body 111, and the temperature of the refrigerant. In this embodiment, the acquisition unit 121 periodically acquires the temperature of the refrigerant, the heat generation amount of the heater HT for each area A, and the temperature of the main body 111.

[0043] The correction unit 122 and the prediction unit 123 will be described in detail later.

[0044] The heat generation control unit 124 controls the heater power supply 60 via the external interface 101 to control the heat generation amount of each heater HT. For example, the heat generation control unit 124 outputs control data specifying the power to be supplied to each heater HT to the heater power supply 60, thereby controlling the heat generation amount of each heater HT. In this embodiment, the heat generation control unit 124 outputs control data specifying the duty ratio of each heater HT to the heater power supply 60. The heater power supply 60 supplies power to each heater HT at the specified duty ratio based on the control data. The heater HT generates heat at an amount corresponding to the supplied power. For example, if the heater power supply 60 is capable of supplying 100 W of power per unit time to one heater HT and the duty ratio is specified as 20%, the heater power supply 60 controls the duty ratio of the power supplied to the heater HT to 20%, thereby supplying 20 W of power per unit time to the heater HT. In this case, the heater HT generates heat at an amount of 20 W per unit time.

[0045] Next, the flow of the plasma processing will be briefly described.

[0046] The substrate W is carried into the plasma processing chamber 10 through a loading / unloading port (not shown) by a transport mechanism such as a transport arm, and placed on the central region 111 a of the substrate support 11 .

[0047] The plasma control unit 120 controls the plasma processing. For example, the plasma control unit 120 controls the exhaust system 40 to evacuate the plasma processing chamber 10 to a predetermined vacuum level. The plasma control unit 120 controls the gas supply unit 20 to introduce a processing gas from the gas supply unit 20 into the plasma processing space 10s. The plasma control unit 120 controls the power supply 30 to supply a source RF signal and a bias RF signal from the first RF generation unit 31a and the second RF generation unit 31b in accordance with the introduction of the processing gas, thereby generating plasma in the plasma processing chamber 10.

[0048] In plasma processing, the progress of the processing changes depending on the temperature of the substrate W. For example, in plasma etching, the etching progress rate changes depending on the temperature of the substrate W. Therefore, the plasma processing apparatus 1 may be configured to control the temperature of the substrate W by detecting the temperature of the main body 111 with the temperature sensor TS and performing feedback control so that the main body 111 reaches a predetermined temperature by heating with the heater HT and cooling with a refrigerant.

[0049] However, heat input to the substrate W may occur from a heat source that appears within the plasma processing chamber 10. A heat source is a source that supplies heat to the substrate W. Components or spaces within the plasma processing chamber 10 that have a temperature higher than that of the substrate W serve as heat sources. Heat sources appear within the plasma processing chamber 10. For example, plasma generated within the plasma processing chamber 10 during plasma processing serves as a heat source. During plasma processing, heat input to the substrate W occurs from the plasma. Furthermore, components within the plasma processing chamber 10 serve as heat sources when they are heated by the plasma or the like and reach a temperature higher than that of the substrate W. Heat input to the substrate W occurs due to radiation from heated components within the plasma processing chamber 10. As such, the plasma processing apparatus 1 may experience heat input to the substrate W from heat sources such as plasma and heated components within the plasma processing chamber 10, making it difficult to accurately control the temperature of the substrate W.

[0050] Therefore, the plasma processing apparatus 1 according to this embodiment controls the temperature of the substrate W as follows.

[0051] The acquisition unit 121 periodically acquires the heat generation amount of each heater HT, the temperature of the main body 111, and the temperature of the coolant. In this embodiment, the acquisition unit 121 periodically acquires the temperature of the coolant, the heat generation amount of the heater HT in each area A, and the temperature of the main body 111.

[0052] For example, the acquisition unit 121 acquires the temperature of each temperature sensor TS arranged in each area A from the temperature detection unit 61 via the external interface 101 as the temperature of the main body 111 of each area A. The acquisition unit 121 also acquires the temperature of the refrigerant from the chiller unit 14 via the external interface 101. The refrigerant temperature may also be acquired from a thermometer installed in the pipe 14a.

[0053] The acquisition unit 121 also acquires the heat generation amount of the heater HT in each area A from the heat generation control unit 124. For example, the acquisition unit 121 acquires the power supplied to the heater HT in each area A controlled by the heat generation control unit 124 from the heat generation control unit 124. The acquisition unit 121 identifies the acquired power supplied to the heater HT in each area A as the heat generation amount of the heater HT in each area A. In this embodiment, the acquisition unit 121 acquires the duty ratio of the heater HT in each area A controlled by the heat generation control unit 124 from the heat generation control unit 124. The acquisition unit 121 calculates the power supplied to the heater HT in each area A from the duty ratio of the heater HT in each area A and the power that the heater power supply 60 can supply to the heater HT in each area A. For example, if the duty ratio is 20% and the heater power supply 60 can supply 100 W of power per unit time to the heater HT in area A, the acquiring unit 121 determines the power supply to the heater HT as 20 W per unit time. The acquiring unit 121 determines the determined 20 W per unit time as the heat generation amount of the heater HT.

[0054] The correction unit 122 corrects the refrigerant temperature acquired by the acquisition unit 121 to the refrigerant temperature in each area A along the flow path 1110a.

[0055] The prediction unit 123 predicts the temperature of the substrate W in each area A using a prediction model for predicting the temperature of the substrate W.

[0056] The prediction model will now be described. The prediction model can be expressed as a mathematical model that calculates the temperature of the substrate W in each area A by multiplying the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the coolant, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the coolant in each area A and in that area A and all other areas A by coefficients and adding them up. For example, the prediction model can be expressed as a calculation formula such as the following formula (1) using a thermal network method or a polynomial approximation model.

[0057]

[0058] Here, n is a number assigned to each area A in order. １ ~T ｎ is the temperature of the substrate W in the area A numbered 1 to n. １ ~p ｎ is the heat generation amount of the heater HT in the area A numbered 1 to n. １ ~T' ｎ is the temperature of the main body 111 in the area A numbered 1 to n. １ ~T” ｎ is the temperature of the refrigerant in area A numbered 1 to n. １,１ ~a ｎ,ｎ is the heat generation amount p of the heater HT １ ~p ｎ is the coefficient for b １,１ ~b ｎ,ｎ is the temperature T′ of the main body 111 １ ~T' ｎ is the coefficient for １,１ ~c ｎ,ｎ is the temperature T′ of the main body 111 １ ~T' ｎ is the coefficient for the time derivative of d １,１ ~d ｎ,ｎ is the refrigerant temperature T １ ~T” ｎ is the coefficient for １,１ ~e ｎ,ｎ is the refrigerant temperature T １ ~T” ｎ is the coefficient for the time derivative of

[0059] The heat flow in the portions related to the substrate W and the main body 111 can be expressed as a thermal circuit by the thermal network method. Fig. 5 is a diagram showing an example of a thermal circuit representing the substrate W and the main body 111 according to the embodiment.

[0060] In the thermal circuit shown in Figure 5, the substrates W in areas A numbered 1 to n are represented as nodes #1 to #n, the main body 111 in areas A numbered 1 to n are represented as nodes #n+1 to #2n, and the coolant in the flow path 1110a is represented as nodes #2n+1 to #3n. The coolant flows through the flow path 1110a. Heat transferred to the coolant flows away along with the coolant. For this reason, nodes #2n+1 to #3n are represented as constant potential points using ground symbols.

[0061] In the plasma processing apparatus 1, heat is transferred between the substrate W and the main body 111 and between the main body 111 and the coolant in the flow path 1110a according to the temperature difference for each area A. In the thermal circuit shown in Fig. 5, the thermal resistance between the substrate W and the main body 111 is represented as thermal resistance R1, and the thermal resistance between the main body 111 and the coolant in the flow path 1110a is represented as thermal resistance R2.

[0062] Furthermore, in the plasma processing apparatus 1, heat is transferred between the areas A of the substrate W and the main body 111 according to the temperature difference. In the thermal circuit shown in Fig. 5, the thermal resistance between the areas A of the substrate W is represented as thermal resistance R3, and the thermal resistance between the areas A of the main body 111 is represented as thermal resistance R4.

[0063] In addition, in the plasma processing apparatus 1, a heater HT is provided in the main body 111 for each area A, and the heat generated by the heater HT is transferred to the main body 111. In the thermal circuit shown in Fig. 5, a variable heat source P1 representing a heater HT is connected to each of nodes #n+1 to #2n representing the main body 111.

[0064] Furthermore, in the plasma processing apparatus 1, heat is input to the substrate W from a heat source such as plasma or heated components in the plasma processing chamber 10 for each area A. In the thermal circuit shown in Fig. 5, the heat source for each area A numbered 1 to n is represented as a variable heat source P2. Note that the thermal circuit shown in Fig. 5 illustrates a state in which no heat is input to each area A from the variable heat source P2, and illustrates a separated state in which the variable heat source P2 for each area A and nodes #1 to #n are separated in terms of the circuit. When heat input from the variable heat source P2 to each area A is taken into consideration, the variable heat source P2 for each area A and nodes #1 to #n are connected in terms of the circuit.

[0065] For nodes #1 to #3n, the simultaneous equations of heat balance can be expressed as the following equations (2-1) to (2-3n).

[0066]

[0067] Here, Q is the heat input (W) at each node. For example, Q １ is the heat input to node #1. G is the thermal conductivity (W / K) between each node. For example, G １,ｉ is the thermal conductivity of node #1 and node #i. T is the temperature (degC) of each node. For example, T １ is the temperature of node #1. t is time (sec). C is the heat capacity of each node. For example, C １ is the heat capacity of node #1.

[0068] The left side of each equation of the simultaneous equations of heat balance is calculated by multiplying the temperature difference between nodes #1 to #3n by the thermal conductivity G for each node, where i is 1 to 3n, to find the sum, and then adding the sum to the heat input Q. For example, the left side of equation (2-1) is calculated by multiplying the temperature difference between nodes #1 to #3n (T ｉ -T １ ) and thermal conductivity G １,ｉ Multiply by to get the sum, and the heat input Q １ and the sum is added.

[0069] Note that equations (2-1) to (2-3n) are expressed as equations that include terms for heat transfer between all nodes #1 to #3n. For nodes between which heat transfer is not taken into consideration, the thermal conductivity G between the nodes is set to, for example, zero. For example, for nodes not connected by the thermal circuit shown in FIG. 5, the thermal conductivity G between the nodes is set to, for example, zero.

[0070] For example, the simultaneous equations for the heat balance of node #1 shown in FIG. 5 can be expressed as the following equation (3).

[0071]

[0072] The above equation (1) can be obtained from the simultaneous equations of the heat balance of nodes #1 to #3n. In addition, the above equation (1) can be obtained in the same way when a polynomial approximation model is used.

[0073] Coefficient a in Equation (1) １,１ ~a ｎ,ｎ , b １,１ ~b ｎ,ｎ , c １,１ ~c ｎ,ｎ , d １,１ ~d ｎ,ｎ , e １,１ ~e ｎ,ｎ The values ​​of can be determined by performing fitting using fitting data. The fitting data is generated by the plasma processing apparatus 1 by determining the relationships among the temperature of the substrate W in each area A, the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the coolant, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the coolant.

[0074] For example, when generating fitting data, a substrate W is placed in the central region 111a of the substrate support 11. When generating fitting data, the process controller 104 controls the heater power supply 60 to cause each heater HT to generate heat while circulating a coolant from the chiller unit 14 through the flow path 1110a for cooling without generating plasma. The process controller 104 measures the temperature of the substrate W in each area A, the heat generation amount of the heater HT, the temperature of the main body 111, and the temperature of the coolant. The temperature of the substrate W in each area A is measured, for example, by using a temperature sensor such as an infrared camera disposed in the plasma processing chamber 10. The temperature of the substrate W in each area A is also measured, for example, by using a sensor substrate configured to measure temperature. The process controller 104 periodically measures the temperature of the substrate W in each area A, the heat generation amount of the heater HT, the temperature of the main body 111, and the temperature of the coolant, including during transitional periods when the temperatures are changing, for a variety of patterns by changing the temperature of the coolant and the heat generation amount of each heater HT. The process controller 104 generates fitting data that stores the measured time, the temperature of the substrate W in each area A, the heat generation amount of the heater HT, the temperature of the main body 111, and the temperature of the coolant.

[0075] The temperature of the refrigerant in each area A may be the temperature of the refrigerant measured by the chiller unit 14.

[0076] Here, the temperature of the refrigerant flowing through the flow path 1110a gradually increases due to heat input from the base 1110. Therefore, the temperature of the refrigerant in each area A of the fitting data may be corrected to correspond to the temperature increase along the flow path 1110a. For example, the amount of temperature increase of the refrigerant when the refrigerant passes through the flow path 1110a is calculated. Also, the total length from one end of the flow path 1110a where the refrigerant flows in to the other end where the refrigerant flows out is calculated. Also, the length of the flow path 1110a to each area A is calculated. The length of the flow path 1110a to each area A is measured from one end along the flow path 1110a. The total length of the flow path 1110a and the length of the flow path 1110a to each area A may be calculated from the design data of the base 1110, or the base 1110 may be actually measured. In correcting the refrigerant temperature, the amount of increase in refrigerant temperature for each area A is calculated by multiplying the amount of increase in refrigerant temperature over the entire length of flow path 1110a by the ratio of the length of flow path 1110a up to area A to the entire length of flow path 1110a. In correcting the refrigerant temperature, the amount of increase in refrigerant temperature calculated for each area A is added to the refrigerant temperature measured by a thermometer installed in chiller unit 14 or piping 14a to calculate the refrigerant temperature for each area A. Note that the amount of increase in refrigerant temperature for each area A may be determined by simulation or the like.

[0077] By fitting the equation (1) using such fitting data, the coefficient a １,１ ~a ｎ,ｎ , b １,１ ~b ｎ,ｎ , c １,１ ~c ｎ,ｎ , d １,１ ~d ｎ,ｎ , e １,１ ~e ｎ,ｎ can each specify an appropriate value.

[0078] The prediction model data 110 includes the coefficient a １,１ ~a ｎ,ｎ , b １,１ ~b ｎ,ｎ , c １,１ ~c ｎ,ｎ , d １,１ ~d ｎ,ｎ , e １,１ ~e ｎ,ｎThe formula (1) in which the specified values ​​are set is stored.

[0079] The acquisition unit 121 periodically acquires the heat generation amount of each heater HT, the temperature of the main body 111, and the temperature of the coolant. In this embodiment, the acquisition unit 121 periodically acquires the coolant temperature, the heat generation amount of the heater HT, and the temperature of the main body 111 for each area A. The period at which the acquisition unit 121 acquires the coolant temperature, the heat generation amount of the heater HT, and the temperature of the main body 111 may be any period at which the time derivative of the temperature of the main body 111 and the time derivative of the coolant temperature can be calculated. For example, the period is preferably 0.01 to 0.1 seconds, and more preferably 0.0001 to 0.01 seconds.

[0080] The correction unit 122 corrects the refrigerant temperature acquired by the acquisition unit 121 to the refrigerant temperature in each area A in accordance with the temperature increase along the flow path 1110a. For example, the correction unit 122 calculates the amount of refrigerant temperature increase for each area A by multiplying the amount of refrigerant temperature increase over the entire length of the flow path 1110a by the ratio of the length of the flow path 1110a up to the area A to the entire length of the flow path 1110a. The correction unit 122 then calculates the refrigerant temperature for each area A by adding the calculated amount of refrigerant temperature increase for each area A to the refrigerant temperature measured by a thermometer installed in the chiller unit 14 or the piping 14a. Note that the correction unit 122 may also calculate the refrigerant temperature for each area A by adding the amount of refrigerant temperature increase for each area A obtained by simulation or the like to the refrigerant temperature measured by a thermometer installed in the chiller unit 14 or the piping 14a.

[0081] The prediction unit 123 predicts the temperature of the substrate W for each area A using the prediction model stored in the prediction model data 110. The prediction unit 123 predicts the temperature of the substrate W for each area A using equation (1) from the corrected coolant temperature in each area A, the acquired heat generation amount of the heater HT, the temperature of the main body 111, the time derivative of the temperature of the main body 111, and the time derivative of the coolant temperature for each area A. For example, the prediction unit 123 calculates the temperature of the substrate W in each area A by substituting the coolant temperature, the heat generation amount of the heater HT, the temperature of the main body 111, the time derivative of the temperature of the main body 111, and the time derivative of the coolant temperature for each area A into equation (1). The prediction unit 123 can accurately predict the temperature of the substrate W by using equation (1).

[0082] The heat control unit 124 controls the heat generation amount of the heater HT so that the temperature of the substrate W predicted by the prediction unit 123 becomes a predetermined temperature. A set temperature of the substrate W is set in the heat generation control unit 124. The heat generation control unit 124 controls the heat generation amount of the heater HT so that the temperature of the substrate W predicted by the prediction unit 123 becomes the set temperature. For example, during plasma processing, the set temperature of the substrate W stored in the recipe is set in the heat generation control unit 124 for each area A of the substrate W. The heat generation control unit 124 controls the heat generation amount of the heater HT for each area A so that the temperature of the substrate W becomes the set temperature. For example, the heat generation control unit 124 controls the heater power supply 60 so that the heat generation amount of the heater HT in the area A where the predicted temperature of the substrate W is lower than the set temperature is increased and the heat generation amount of the heater HT in the area A where the predicted temperature of the substrate W is higher than the set temperature is decreased. For example, the heat generation control unit 124 outputs control data to the heater power supply 60 to increase the duty ratio of area A where the predicted temperature of the substrate W is lower than the set temperature, and to decrease the duty ratio of area A where the predicted temperature of the substrate W is higher than the set temperature.

[0083] [Specific Example of Substrate Temperature Control Process Flow] Next, a specific example of the flow of a substrate temperature control process including a substrate temperature control method according to an embodiment will be described. Fig. 6 is a flowchart showing an example of the flow of a substrate temperature control process according to an embodiment. The substrate temperature control process according to the embodiment is performed when plasma processing is started. When plasma processing is started, the heat control unit 124 is set with the set temperature of the substrate W stored in the recipe for each area A of the substrate W.

[0084] The acquiring unit 121 acquires the heat value of the heater HT, the temperature of the main body 111, and the temperature of the coolant (step S10). For example, the acquiring unit 121 acquires the temperature of the coolant, the heat value of the heater HT, and the temperature of the main body 111 for each area A.

[0085] The correcting unit 122 corrects the refrigerant temperature acquired by the acquiring unit 121 to the refrigerant temperature of each area A (step S11).

[0086] The prediction unit 123 predicts the temperature of the substrate W in each area A using the prediction model stored in the prediction model data 110 (step S12). For example, the prediction unit 123 predicts the temperature of the substrate W in each area A from the coolant temperature in each area A corrected using equation (1), the acquired heat generation amount of the heater HT in each area A, the temperature of the main body 111, the time derivative of the temperature of the main body 111, and the time derivative of the coolant temperature.

[0087] The heat control unit 124 controls the heat generation amount of the heater HT for each area A so that the temperature of the substrate W predicted by the prediction unit 123 becomes the set temperature (step S13).

[0088] The heat generation control unit 124 determines whether or not a temperature control stop signal instructing the temperature control to be stopped has been received (step S14). If the temperature control stop signal has not been received (step S14: No), the process proceeds to step S10 described above. If the temperature control stop signal has been received (step S14: Yes), the process ends. The substrate temperature control process continues until the temperature control stop signal is received, even if the plasma process has ended.

[0089] As a result, the plasma processing apparatus 1 according to the embodiment can accurately control the temperature of each area A of the substrate W to a set temperature.

[0090] In the above embodiment, the prediction model is described as a prediction model that includes, for each area A, a term for heat transfer from the area A and all other areas A. However, this is not limited to this. For example, the prediction model may be a prediction model that includes, for each area A, a term for heat transfer from the area A and some other areas A. The other some areas A may be areas A where heat transfer occurs to the area A, and may be areas A surrounding the area A, or areas A adjacent to the area A.

[0091] In the above embodiment, the temperature of the substrate W is predicted for each area A obtained by dividing the central region 111a of the main body 111, and the heat generation amount of the heater HT is controlled for each area A so that the temperature of the substrate W reaches the set temperature. However, this is not limiting. For example, instead of dividing the central region 111a of the main body 111 into areas A, the temperature of the substrate W may be predicted for the central region 111a as a single area A, and the heat generation amount of the heater HT may be controlled so that the temperature of the substrate W reaches the set temperature.

[0092] In the above embodiment, the thermal circuit representing the substrate W and the main body 111 is shown as having the configuration in Fig. 5 . However, this is not limiting. The thermal circuit representing the substrate W and the main body 111 may have additional nodes in consideration of heat transfer between the temperature sensor TS and the heater HT within the main body 111. For example, the thermal circuit representing the substrate W and the main body 111 may have a circuit configuration in which additional nodes are added between the nodes #1 to #n and the nodes #n+1 to #2n of the thermal circuit of the configuration in Fig. 5 , and the variable heat source P1 representing each heater HT is connected to the added nodes.

[0093] In the above embodiment, the prediction model (Equation (1)) calculated from the fitting data generated in the plasma processing apparatus 1 is stored in the prediction model data 110. However, this is not limiting. The prediction model in the prediction model data 110 may store a prediction model calculated in another plasma processing apparatus. For example, when a plurality of plasma processing apparatuses are operated, the coefficient a １,１ ~a ｎ,ｎ , b １,１ ~b ｎ,ｎ , c １,１ ~c ｎ,ｎ , d １,１ ~d ｎ,ｎ , e １,１ ~e ｎ,ｎ may be specified to determine equation (1), and the determined equation (1) may be used in multiple plasma processing apparatuses. Furthermore, the prediction model in the prediction model data 110 may be provided by the manufacturer of the plasma processing apparatus. The prediction model may be adjustable for individual differences between plasma processing apparatuses. For example, a correction term may be added to equation (1) to absorb individual differences between plasma processing apparatuses. Each plasma processing apparatus 1 may use a prediction model in which the correction term is adjusted according to the individual differences between the plasma processing apparatuses 1. For example, a standard equation (1) is determined for a standard plasma processing apparatus. Each plasma processing apparatus 1 stores equation (1) with the adjusted correction term as a prediction model in the prediction model data 110.

[0094] In the above embodiment, the plasma processing is performed on a semiconductor wafer as the substrate W, but the present invention is not limited to this.

[0095] In the above embodiment, the substrate processing apparatus is described as a plasma processing system that performs a plasma etching process. However, the present invention is not limited to this. The substrate processing apparatus may be any apparatus that produces a heat source that inputs heat to the substrate W. For example, the substrate processing apparatus may be a film formation apparatus that generates plasma to form a film. Furthermore, the substrate processing apparatus may be a heat processing apparatus that performs a heat treatment such as ashing on the substrate W using a heat source such as a light source or heater.

[0096] As described above, the plasma processing system (substrate processing apparatus) according to the embodiment includes the main body 111 (stage), the plasma processing chamber 10 (chamber), a cooling mechanism (coolant, flow path 1110a, etc.), the heater HT (heating mechanism), the temperature sensor TS (measurement unit), the acquisition unit 121, the prediction unit 123, and the heat generation control unit 124. The main body 111 accommodates a substrate W. The plasma processing chamber 10 includes the main body 111 therein, and a heat source that inputs heat to the substrate W placed in the main body 111 emerges. The cooling mechanism is provided in the main body 111 and cools the main body 111. The heater HT is provided between the central region 111a (mounting surface) of the main body 111 on which the substrate W is placed and the cooling mechanism, and is capable of controlling the amount of heat generated by the heater HT, thereby heating the main body 111. The temperature sensor TS measures the temperature of the main body 111. The acquisition unit 121 periodically acquires the heat generation amount of the heater HT, the temperature of the main body 111, and the temperature of the cooling mechanism. The prediction unit 123 predicts the temperature of the substrate W from the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the cooling mechanism, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the cooling mechanism using a calculation formula (e.g., Equation (1)) for predicting the temperature of the substrate W from the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the cooling mechanism acquired by the acquisition unit 121, and the time derivative of the temperature of the main body 111 and the time derivative of the temperature of the cooling mechanism. The heat generation control unit 124 controls the heat generation amount of the heater HT so that the temperature of the substrate W predicted by the prediction unit 123 becomes a predetermined temperature. This allows the plasma processing system according to the embodiment to accurately control the temperature of the substrate W.

[0097] The calculation formula is a prediction model that calculates the temperature of the substrate W by multiplying the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the cooling mechanism, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the cooling mechanism by coefficients and adding them up. As a result, the plasma processing system according to the embodiment can predict the temperature of the substrate W using the prediction model, and therefore can accurately control the temperature of the substrate W.

[0098] The calculation formula is a mathematical model that calculates the temperature of the substrate W by multiplying the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the cooling mechanism, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the cooling mechanism by respective coefficients and adding the results together. The values ​​of the coefficients of the mathematical model are determined using data that has been obtained in advance regarding the relationships between the temperature of the substrate W, the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the cooling mechanism, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the cooling mechanism. As a result, the plasma processing system according to the embodiment can predict the temperature of the substrate W using the mathematical model, thereby enabling accurate control of the temperature of the substrate W.

[0099] Furthermore, the values ​​of the coefficients of the mathematical model are determined by performing fitting using data. As a result, the plasma processing system according to the embodiment can predict the temperature of the substrate W using the mathematical model, and therefore can control the temperature of the substrate W with high accuracy.

[0100] Furthermore, the main body 111 has a central region 111a on which a substrate W is placed, which is divided into a plurality of areas A. A cooling mechanism is provided in each area A of the main body 111. A heater HT is provided in each area A of the main body 111. A temperature sensor TS is provided in each area A of the main body 111 and measures the temperature of the main body 111 for each area A. The acquisition unit 121 periodically acquires the temperature of the cooling mechanism, the heat generation amount of the heater HT, and the temperature of the main body 111 for each area A. The prediction unit 123 uses a calculation formula to predict the temperature of the substrate W in each area A from the temperature of the cooling mechanism acquired by the acquisition unit 121, the heat generation amount of the heater HT and the temperature of the main body 111 for each area A, the time derivative of the temperature of the main body 111 for each area A, and the time derivative of the temperature of the cooling mechanism. As a result, the plasma processing system according to the embodiment can predict the temperature of the substrate W in each area A, thereby enabling accurate control of the temperature of the substrate W in each area A.

[0101] The calculation formula is a mathematical model that calculates the temperature of the substrate W in each area A by multiplying the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the cooling mechanism, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the cooling mechanism in the area A and other areas A by coefficients and adding the results together. The values ​​of the coefficients of the mathematical model are determined using data that has been obtained in advance regarding the relationships between the temperature of the substrate W in each area A, the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the cooling mechanism, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the cooling mechanism. As a result, the plasma processing system according to the embodiment can predict the temperature of the substrate W in each area A by using the mathematical model, taking heat transfer with other areas A into consideration, and therefore can accurately control the temperature of the substrate W in each area A.

[0102] Furthermore, the values ​​of the coefficients of the mathematical model are determined by performing fitting using data. As a result, the plasma processing system according to the embodiment can predict the temperature of the substrate W in each area A using the mathematical model, and therefore can accurately control the temperature of the substrate W in each area A.

[0103] The calculation formula is a mathematical model that calculates the temperature of the substrate W in each area A by multiplying the heat generation amount of the heater HT, the temperature of the main body 111, the temperature of the cooling mechanism, the time derivative of the temperature of the main body 111, and the time derivative of the temperature of the cooling mechanism in each area A and all other areas A by a coefficient and adding the results together. As a result, the plasma processing system according to the embodiment can predict the temperature of the substrate W in each area A by using the mathematical model, taking into account heat transfer with all other areas A, and therefore can accurately control the temperature of the substrate W in each area A.

[0104] The cooling mechanism is a flow path 1110a formed to pass through all areas A of the main body 111, through which a coolant flows. The correction unit 122 acquires the temperature of the coolant flowing into the flow path 1110a. The plasma processing system according to the embodiment further includes the correction unit 122. The correction unit 122 corrects the coolant temperature acquired by the acquisition unit 121 to the coolant temperature in each area A along the flow path 1110a. The prediction unit 123 uses a calculation formula to predict the temperature of the substrate W in each area A from the coolant temperature in each area A corrected by the correction unit 122, the heat generation amount of the heater HT and the temperature of the main body 111 in each area A acquired by the acquisition unit 121, the temperature of the cooling mechanism in each area A, and the time derivative of the temperature of the main body 111. As a result, the plasma processing system according to the embodiment can predict the temperature of the substrate W in each area A using the coolant temperature in each area A, thereby accurately controlling the temperature of each area A.

[0105] The prediction unit 123 predicts the temperature of the substrate W in the presence of a heat source. The heat source is either plasma or a heated component in the plasma processing chamber 10. This allows the plasma processing system according to the embodiment to predict the temperature of the substrate W receiving heat input from the heat source, thereby enabling accurate control of the temperature of the substrate W receiving heat input from the heat source.

[0106] It should be noted that the disclosed embodiments are illustrative in all respects and should not be considered 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.

[0107] In addition, the following supplementary notes are disclosed regarding the above-described embodiment.

[0108] a heat generation control unit that controls the heat generation amount of the heating mechanism so that the substrate temperature predicted by the prediction unit becomes a predetermined temperature.

[0109] (Supplementary Note 2) The substrate processing apparatus according to Supplementary Note 1, wherein the calculation formula is a prediction model that predicts the temperature of the substrate from the heat generation amount of a heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, a time derivative of the temperature of the stage, and a time derivative of the temperature of the cooling mechanism.

[0110] (Supplementary Note 3) The substrate processing apparatus according to Supplementary Note 1 or 2, wherein the calculation formula is a mathematical model that calculates the temperature of the substrate by multiplying the heat generation amount of the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time derivative of the temperature of the stage, and the time derivative of the temperature of the cooling mechanism by coefficients and adding them up, and the values ​​of the coefficients of the mathematical model are determined using data that has been previously obtained showing the relationship between the temperature of the substrate, the heat generation amount of the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time derivative of the temperature of the stage, and the time derivative of the temperature of the cooling mechanism.

[0111] (Supplementary Note 4) The substrate processing apparatus according to Supplementary Note 3, wherein values ​​of the coefficients of the mathematical model are determined by performing fitting using the data.

[0112] (Supplementary Note 5) The substrate processing apparatus of Supplementary Note 1, wherein the stage has a placement surface divided into a plurality of areas, the cooling mechanism is provided in all areas of the stage, the heating mechanism is provided in each area of ​​the stage, the measurement unit is provided in each area of ​​the stage and measures the temperature of the stage in each area, the acquisition unit periodically acquires the temperature of the cooling mechanism, the heat generation amount of the heating mechanism and the temperature of the stage in each area, and the prediction unit uses the calculation formula to predict the temperature of the substrate in each area from the temperature of the cooling mechanism acquired by the acquisition unit, the heat generation amount of the heating mechanism and the temperature of the stage in each area, a time derivative of the temperature of the stage in each area, and a time derivative of the temperature of the cooling mechanism.

[0113] (Supplementary Note 6) The substrate processing apparatus according to Supplementary Note 3, wherein the calculation formula is a mathematical model that calculates the temperature of the substrate in each area by multiplying the heat generation amount of the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time derivative of the temperature of the stage, and the time derivative of the temperature of the cooling mechanism in the area in question and in other areas by a coefficient and adding the results together, and the values ​​of the coefficients of the mathematical model are determined using data that has been previously obtained showing the relationship between the temperature of the substrate in each area, the heat generation amount of the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time derivative of the temperature of the stage, and the time derivative of the temperature of the cooling mechanism.

[0114] (Supplementary Note 7) The substrate processing apparatus according to Supplementary Note 6, wherein the values ​​of the coefficients of the mathematical model are determined by performing fitting using the data.

[0115] (Supplementary Note 8) The substrate processing apparatus according to Supplementary Note 6 or 7, wherein the calculation formula is a mathematical model that calculates the temperature of the substrate in each area by multiplying the heat generation amount of the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time derivative of the temperature of the stage, and the time derivative of the temperature of the cooling mechanism in that area and all other areas by a coefficient and adding them up.

[0116] (Supplementary Note 9) The substrate processing apparatus according to any one of Supplementary Notes 5 to 8, wherein the cooling mechanism is a flow path through which a coolant flows, the flow path being formed to pass through all areas of the stage, and the acquisition unit acquires the temperature of the coolant flowing into the flow path.

[0117] (Supplementary Note 10) A substrate processing apparatus as described in Supplementary Note 9, further comprising a correction unit that corrects the coolant temperature acquired by the acquisition unit to the coolant temperature in each area along the flow path, and the prediction unit uses the calculation formula to predict the temperature of the substrate in each area from the coolant temperature in each area corrected by the correction unit, the heat generation amount of the heating mechanism and the temperature of the stage in each area acquired by the acquisition unit, and the time derivative of the temperature of the cooling mechanism and the temperature of the stage in each area.

[0118] (Supplementary Note 11) The substrate processing apparatus according to any one of Supplementary Notes 1 to 10, wherein the prediction unit predicts the temperature of the substrate in a state in which the heat source is present.

[0119] (Supplementary Note 12) The substrate processing apparatus according to any one of Supplementary Notes 1 to 11, wherein the heat source is at least one of plasma and a heated component within the chamber.

[0120] (Supplementary Note 13) A substrate temperature control method for a substrate processing apparatus having: a stage on which a substrate is placed; a chamber in which the stage is installed and in which a heat source that inputs heat to the substrate placed on the stage appears; a cooling mechanism that is installed on the stage and cools the stage; a heating mechanism that is installed between a mounting surface of the stage on which the substrate is placed and the cooling mechanism and that heats the stage, the heating mechanism being capable of controlling the amount of heat generated; and a measurement unit that measures a temperature of the stage, the method comprising: a) periodically acquiring the amount of heat generated by the heating mechanism, the temperature of the stage, and the temperature of the cooling mechanism; b) predicting the temperature of the substrate from the acquired amount of heat generated by the heating mechanism, the temperature of the stage, and the temperature of the cooling mechanism, as well as the time derivative of the temperature of the stage and the time derivative of the temperature of the cooling mechanism, using a calculation formula that predicts the temperature of the substrate from the amount of heat generated by the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, a time derivative of the temperature of the stage, and a time derivative of the temperature of the cooling mechanism; c) controlling the amount of heat generated by the heating mechanism so that the predicted temperature of the substrate becomes a predetermined temperature.

[0121] 1 Plasma processing apparatus 10 Plasma processing chamber 11 Substrate support 14 Chiller unit 14a Piping 60 Heater power supply 61 Temperature detection unit 100 Control unit 101 External interface 102 User interface 103 Memory unit 104 Process controller 110 Prediction model data 111 Main body 111a Central region 111b Annular region 112 Ring assembly 120 Plasma control unit 121 Acquisition unit 122 Correction unit 123 Prediction unit 124 Heat generation control unit 1110 Base 1110a Flow path 1111 Electrostatic chuck 1111a Ceramic member 1111b Electrostatic electrode A, A1 to A14 Area HT Heater TS Temperature sensor W Substrate

Claims

1. A substrate processing apparatus, comprising: a stage on which a substrate is placed; a chamber provided inside the stage, in which a heat source for heating the substrate placed on the stage appears; a cooling mechanism provided on the stage for cooling the stage; a heating mechanism provided between the placement surface of the stage for placing the substrate and the cooling mechanism, capable of controlling the amount of heat generated, for heating the stage; a measuring unit for measuring the temperature of the stage; an acquisition unit for periodically acquiring the amount of heat generated by the heating mechanism, the temperature of the stage, and the temperature of the cooling mechanism; a prediction unit for predicting the temperature of the substrate from the amount of heat generated by the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time differential of the temperature of the stage, and the time differential of the temperature of the cooling mechanism, using a calculation formula for predicting the temperature of the substrate; and a heat generation control unit for controlling the amount of heat generated by the heating mechanism so that the temperature of the substrate predicted by the prediction unit becomes a predetermined temperature.

2. The substrate processing apparatus according to claim 1, wherein the calculation formula is a prediction model for predicting the temperature of the substrate from the amount of heat generated by the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time differential of the temperature of the stage, and the time differential of the temperature of the cooling mechanism.

3. The substrate processing apparatus according to claim 1, wherein the calculation formula is a mathematical model for calculating the temperature of the substrate by multiplying and adding coefficients to the amount of heat generated by the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time differential of the temperature of the stage, and the time differential of the temperature of the cooling mechanism, respectively, and the values of the coefficients of the mathematical model are determined using data obtained in advance on the relationship between the temperature of the substrate, the amount of heat generated by the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time differential of the temperature of the stage, and the time differential of the temperature of the cooling mechanism.

4. The substrate processing apparatus according to claim 3, wherein the values of the coefficients of the mathematical model are determined by performing fitting using the data.

5. The stage has a placement surface divided into a plurality of areas. The cooling mechanism is provided in all areas of the stage. The heating mechanism is provided for each area of the stage. The measurement unit is provided for each area of the stage, measures the temperature of the stage for each area, the acquisition unit periodically acquires the temperature of the cooling mechanism, the heat generation amount of the heating mechanism in each area, and the temperature of the stage, and the prediction unit uses the calculation formula to calculate the temperature of the substrate in each area from the temperature of the cooling mechanism acquired by the acquisition unit, the heat generation amount of the heating mechanism in each area, the temperature of the stage, the time differential of the temperature of the stage in each area, and the time differential of the temperature of the cooling mechanism. The substrate processing apparatus according to claim 1.

6. The calculation formula is a mathematical model that calculates the temperature of the substrate in each area by multiplying and adding coefficients to the heat generation amount of the heating mechanism in the area and other areas, the temperature of the stage, the temperature of the cooling mechanism, the time differential of the temperature of the stage, and the time differential of the temperature of the cooling mechanism for each area. The value of each coefficient of the mathematical model is determined using data obtained in advance regarding the relationship between the temperature of the substrate in each area, the heat generation amount of the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time differential of the temperature of the stage, and the time differential of the temperature of the cooling mechanism. The substrate processing apparatus according to claim 5.

7. The value of each coefficient of the mathematical model is determined by performing fitting using the data. The substrate processing apparatus according to claim 6.

8. The calculation formula is a mathematical model that calculates the temperature of the substrate in each area by multiplying and adding coefficients to the heat generation amount of the heating mechanism in the area and all other areas, the temperature of the stage, the temperature of the cooling mechanism, the time differential of the temperature of the stage, and the time differential of the temperature of the cooling mechanism for each area. The substrate processing apparatus according to claim 6.

9. The cooling mechanism is a flow path formed to pass through all areas of the stage through which a refrigerant flows. The acquisition unit acquires the temperature of the refrigerant flowing into the flow path. The substrate processing apparatus according to claim 5.

10. The substrate processing apparatus according to claim 9, further comprising a correction unit that corrects the temperature of the refrigerant acquired by the acquisition unit to the temperature of the refrigerant in each area along the flow path, and the prediction unit uses the calculation formula to calculate the temperature of the refrigerant in each area corrected by the correction unit, the heat generation amount of the heating mechanism in each area acquired by the acquisition unit, the temperature of the stage, the temperature of the cooling mechanism in each area, and the time differential of the temperature of the stage to predict the temperature of the substrate in each area.

11. The substrate processing apparatus according to claim 1, wherein the prediction unit predicts the temperature of the substrate in a state where the heat source appears.

12. The substrate processing apparatus according to claim 1, wherein the heat source is at least one of plasma and a heated component in the chamber.

13. A method for controlling the substrate temperature of a substrate processing apparatus, comprising: a stage on which a substrate is placed; a chamber provided inside the stage, in which a heat source for introducing heat into the substrate placed on the stage appears; a cooling mechanism provided on the stage for cooling the stage; a heating mechanism provided between the placement surface of the stage for placing the substrate and the cooling mechanism, capable of controlling the heat generation amount, for heating the stage; and a measurement unit for measuring the temperature of the stage, the method comprising: a) periodically acquiring the heat generation amount of the heating mechanism, the temperature of the stage, and the temperature of the cooling mechanism; b) using a calculation formula for predicting the temperature of the substrate from the heat generation amount of the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time differential of the temperature of the stage, and the time differential of the temperature of the cooling mechanism, and predicting the temperature of the substrate from the acquired heat generation amount of the heating mechanism, the temperature of the stage, the temperature of the cooling mechanism, the time differential of the temperature of the stage, and the time differential of the temperature of the cooling mechanism; and c) controlling the heat generation amount of the heating mechanism so that the predicted temperature of the substrate becomes a predetermined temperature.

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