Substrate support, electrostatic chuck, plasma processing apparatus, and method for manufacturing electrostatic chuck

Abstract

The purpose of the present invention is to provide a technique capable of quickly controlling a temperature of a substrate and a substrate support. This substrate support is provided with: a base having a flow path through which a temperature control medium flows; a support part disposed on the base, the support part having a front surface that supports the substrate and a rear surface; and a heat flux sensor disposed on the rear surface of the support part.

Description

Substrate support, electrostatic chuck, plasma processing apparatus, and method for manufacturing electrostatic chuck

[0001] SUMMARY Exemplary embodiments of the present disclosure relate to a substrate support, an electrostatic chuck, a plasma processing apparatus, and a method for manufacturing an electrostatic chuck.

[0002] Japanese Patent Application Laid-Open No. 2003-144992 discloses a technique for providing a plasma processing apparatus having a temperature sensor disposed on a stage that supports a substrate.

[0003] Japanese Patent Application Laid-Open No. 2018-206805

[0004] The present disclosure provides techniques that allow rapid temperature control of a substrate or substrate support.

[0005] In one exemplary embodiment of the present disclosure, the substrate support comprises a base including a flow path through which a temperature control medium flows, a support portion disposed on the base, the support portion including a front surface for supporting the substrate and a back surface, and a heat flux sensor disposed on the back surface of the support portion.

[0006] According to one exemplary embodiment of the present disclosure, a technique can be provided that allows for rapid temperature control of a substrate or a substrate support.

[0007] FIG. 1 is a diagram for explaining an example of the configuration of a plasma processing system. FIG. 2 is a diagram for explaining an example of the configuration of a plasma processing apparatus. FIG. 3 is a diagram for explaining an example of the configuration of a processing circuit. FIG. 4 is a diagram for explaining an example of the configuration of a substrate support part. FIG. 5 is a diagram for explaining an example of divided regions of an electrostatic chuck. FIG. 6 is a diagram for explaining an example of the arrangement of heaters in an electrostatic chuck. FIG. 7 is a diagram for explaining an example of the configuration of a heat flux sensor on the back surface of a ceramic member. FIG. 8 is a diagram for explaining an example of a heat flux sensor. FIG. 9 is a flowchart showing an example of a method for manufacturing an electrostatic chuck.

[0008] Hereinafter, each embodiment of the present disclosure will be described.

[0009] In one exemplary embodiment, a substrate support is provided, comprising: a base including a flow path through which a temperature control medium flows; a support disposed on the base, the support including a front surface for supporting a substrate and a back surface; and a heat flux sensor disposed on the back surface of the support.

[0010] In one exemplary embodiment, an adhesive layer is disposed between the base and the support.

[0011] In one exemplary embodiment, the heat flux sensor is a magneto-thermoelectric element.

[0012] In one exemplary embodiment, the heat flux sensor is a magneto-thermoelectric element that utilizes the anomalous Nernst effect.

[0013] In one exemplary embodiment, the heat flux sensor has a thickness in the range of 0.1 μm to 10 μm.

[0014] In one exemplary embodiment, the heat flux sensor is formed by processing the back surface of the support.

[0015] In one exemplary embodiment, the support includes a substrate chuck electrode.

[0016] In one exemplary embodiment, the support includes a heater.

[0017] In one exemplary embodiment, the support includes multiple heaters, with one or more heat flux sensors positioned for each heater.

[0018] In one exemplary embodiment, an electrostatic chuck for holding a substrate is provided, the electrostatic chuck comprising: a dielectric including a front surface for supporting the substrate and a back surface; a substrate chucking electrode disposed within the dielectric; and a heat flux sensor disposed on the back surface of the dielectric.

[0019] In one exemplary embodiment, the heat flux sensor is a magneto-thermoelectric element.

[0020] In one exemplary embodiment, the heat flux sensor is a magneto-thermoelectric element that utilizes the anomalous Nernst effect.

[0021] In one exemplary embodiment, the heat flux sensor has a thickness in the range of 0.1 μm to 10 μm.

[0022] In one exemplary embodiment, the heat flux sensor is formed by processing the backside of a dielectric.

[0023] In one exemplary embodiment, the dielectric includes a heater.

[0024] In one exemplary embodiment, the dielectric includes multiple heaters, with one or more heat flux sensors positioned for each heater.

[0025] In one exemplary embodiment, a plasma processing apparatus is provided, comprising: a chamber; a substrate support disposed within the chamber; a gas supply unit configured to supply a processing gas into the chamber; and a plasma generation unit configured to generate plasma from the processing gas within the chamber, wherein the substrate support comprises a base including a flow path through which a temperature control medium flows; a support disposed on the base, the support including a front surface that supports the substrate and a back surface; and a heat flux sensor disposed on the back surface of the support.

[0026] In one exemplary embodiment, the support further comprises a controller, the controller configured to control the output of the heater based on the heat flux measured by the heat flux sensor.

[0027] In one exemplary embodiment, a method for manufacturing an electrostatic chuck is provided, the method including forming a dielectric having a front surface for supporting a substrate and a back surface, with a substrate chucking electrode disposed within the dielectric, and forming a heat flux sensor on the back surface of the dielectric.

[0028] Hereinafter, each embodiment of the present disclosure will be described in detail with reference to the drawings. In each drawing, the same or similar elements are designated by the same reference numerals, and redundant explanations will be omitted. Unless otherwise specified, the positional relationships, such as up, down, left, and right, will be described based on the positional relationships shown in the drawings. The dimensional ratios in the drawings do not represent actual ratios, and the actual ratios are not limited to the ratios shown in the drawings.

[0029] <An example of a plasma processing system>

[0030] FIG. 1 is a diagram illustrating an exemplary configuration of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing system is an example of a substrate processing system, and the plasma processing apparatus 1 is an example of a substrate processing apparatus. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 (described later), and the gas exhaust port is connected to an exhaust system 40 (described later). The substrate support 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0031] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma generated in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), surface wave plasma (SWP), or the like. Various types of plasma generators may be used, including alternating current (AC) plasma generators and direct current (DC) plasma generators. In one embodiment, the AC signal (AC power) used in the AC plasma generator has a frequency in the range of 100 kHz to 10 GHz. Thus, AC signals include radio frequency (RF) signals and microwave signals. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0032] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform various processes described herein. In one embodiment, part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The control unit 2 may be implemented by, for example, a computer 2a. The processing unit 2a1 may be configured to read a program from the storage unit 2a2 and execute the read program to perform various control operations. This program may be stored in the storage unit 2a2 in advance or may be acquired via a medium when needed. The acquired program is stored in the storage unit 2a2 and read from the storage unit 2a2 by the processing unit 2a1 for execution. The medium may be various storage media readable by the computer 2a or a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). The storage unit 2a2 may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0033] The following describes a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 2 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus.

[0034] The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 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 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0035] 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.

[0036] 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 power supply 31 and / or a DC power supply 32, which will be 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, which will be 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.

[0037] 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.

[0038] 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 passage 1110a, or a combination thereof. A heat transfer fluid such as brine or a gas flows through the flow passage 1110a. In one embodiment, the flow passage 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 substrate support 11 may also include a heat transfer gas supply configured to supply a heat transfer gas to a gap between the backside of the substrate W and the central region 111a.

[0039] 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.

[0040] 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 at least one flow modulation device that modulates or pulses the flow rate of the at least one process gas.

[0041] 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 processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of the plasma generation unit 12. 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.

[0042] 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.

[0043] 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.

[0044] 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 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.

[0045] In various embodiments, 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.

[0046] 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.

[0047] <Configuration Example of Control Unit> Figure 3 illustrates a processing circuit 130 that controls all control processes, statements, or blocks of the flowcharts in this specification on a computer. These control processes, statements, or blocks represent modules, segments, or portions of code containing one or more executable instructions for implementing specific logical functions or steps of the processes. Those skilled in the art will understand that alternative implementations are within the scope of the exemplary embodiments of the present disclosure, and that functions may be performed in a different order from that shown or described, such as substantially simultaneously or in reverse order, depending on the functionality involved. The various elements, features, and processes described herein may be used independently of each other or combined in various ways. All conceivable combinations and subcombinations are within the scope of the present disclosure.

[0048] In one embodiment, processing circuitry 130 may include a CPU 1200 that performs one or more of the control processes described above and / or below. Process data and instructions may be stored in memory 1202. These process data and instructions may be stored on a storage medium disk 1204, such as a hard disk drive (HDD) or a portable storage medium, or may be stored remotely. Furthermore, the claimed disclosure is not limited by the form of computer-readable medium on which instructions for processes according to the disclosure are stored. For example, these instructions may be stored on a CD, DVD, flash memory, RAM, ROM, PROM, EPROM, EEPROM, hard disk, or any other information processing device, such as a server or computer, with which processing circuitry 130 communicates.

[0049] Furthermore, the claimed disclosure may be provided as a utility application, a background daemon, a component of an operating system, or a combination thereof, and may execute in conjunction with CPU 1200 and an operating system known to those skilled in the art, such as Microsoft Windows, UNIX, Solaris, LINUX, Apple MAC-OS, etc.

[0050] In one embodiment, the hardware elements making up processing circuitry 130 may be realized by various circuit elements. Furthermore, each function of the above-described embodiments may be performed by circuitry including one or more processing circuits. A processing circuit includes a specific programmed processing unit, such as processing unit (CPU) 1200. A processing circuit also includes devices such as application specific integrated circuits (ASICs) or conventional circuit components configured to perform the described functions.

[0051] In one embodiment, the processing circuitry 130 may include a CPU 1200 that performs the processes described above. The processing circuitry 130 may be a general-purpose computer or a specialized machine. In one embodiment, the processing circuitry 130 may function as a specialized machine if the processing unit 1200 is programmed to perform backscatter removal from fog using spatial and temporal modulation.

[0052] Alternatively or additionally, CPU 1200 may be implemented on an FPGA, ASIC, PLD, or may use discrete logic circuitry, as will be appreciated by those skilled in the art. Furthermore, CPU 1200 may be implemented as multiple processing units that cooperate to perform the instructions of the processes of the present disclosure described above in parallel.

[0053] The processing circuit 130 may also include a network controller 1206, such as an Intel Ethernet PRO network interface card from Intel Corporation of America, for interfacing with a network 1228. As can be appreciated, the network 1228 may be a public network such as the Internet, a private network such as a LAN or WAN, or any combination thereof, and may also include subordinate networks such as PSTN or ISDN. The network 1228 may also be wired, such as an Ethernet network, or wireless, such as a cellular network including EDGE, 3G, and 4G wireless cellular systems. The wireless network may also be Wi-Fi, Bluetooth, or any other known form of wireless communication.

[0054] The processing circuitry 130 may further include a display device controller 1208, such as a graphics card or graphics adapter, for interfacing with a display device 1210, such as a monitor. A general-purpose I / O interface 1212 may interface with a keyboard and / or mouse 1214 and a touch panel 1216, which may be integral with or separate from the display device 1210. The general-purpose I / O interface may also be connected to various peripheral devices 1218, such as printers and scanners.

[0055] The general purpose storage controller 1224 may be connected to the storage media disk 1204 via a communications bus 1226, such as ISA, EISA, VESA, PCI, etc., to interconnect all components of the processing circuitry 130. The general features and functions of the display device 1210, keyboard and / or mouse 1214, and the display device controller 1208, storage controller 1224, network controller 1206, audio controller, and general purpose I / O interface 1212 are not described herein for the sake of brevity, as they are well known.

[0056] The exemplary circuit elements described in this disclosure may be substituted with other elements and may have different structures than the examples described herein. Additionally, circuits configured to implement the features described herein may be implemented in multiple circuit units (e.g., chips) or these features may be combined as circuits in a single chipset.

[0057] The functions and features described herein may also be performed by various distributed components in a system. For example, these functions may be performed by one or more processing devices, where the processing devices are distributed across multiple components communicating over a network. Distributed components may include various human interface and communication devices (e.g., display monitors, smartphones, tablets, personal digital assistants (PDAs)), as well as one or more client and server machines that can share processing. The network may be a private network, such as a LAN or WAN, or a public network, such as the Internet. Input to the system may be received directly by a user or remotely as a real-time or batch process. Furthermore, portions of the embodiments may be implemented on modules or hardware other than those described above. Accordingly, other embodiments are within the scope of the claims.

[0058] 4 is a diagram for explaining a configuration example of the substrate support part 11. In one embodiment, the substrate support part 11 includes a base 1110, an electrostatic chuck 1111, a heat flux sensor 200, and an adhesive layer 201. The substrate support part 11 may be an example of a substrate support.

[0059] The base 1110 may have a substantially cylindrical shape and may be made of metal, a metal matrix composite (MMC), or ceramics.

[0060] The base 1110 may include a flow path 1110a through which a temperature control medium flows. The flow path 1110a may be disposed inside the base 1110. The flow path 1110a is connected to a medium supply unit 251 provided outside the chamber 10 via a connection flow path 250. The medium supply unit 251 may be configured to supply a temperature control coolant adjusted to a set temperature to the flow path 1110a through the connection flow path 250 and return the temperature control coolant that has passed through the flow path 1110a to the medium supply unit 251 through the connection flow path 250. The base 1110 may be configured to discharge heat input from the electrostatic chuck 1111 by the temperature control medium flowing through the flow path 1110a, thereby cooling the electrostatic chuck 1111 and the substrate W. The temperature control medium may be a gas or a liquid.

[0061] The electrostatic chuck 1111 may include a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. The ceramic member 1111a may be an example of a dielectric material.

[0062] The ceramic member 1111a may have a substantially cylindrical shape. The ceramic member 1111a may include a front surface 300 that supports the substrate W and a back surface 301 that is disposed on the opposite side of the front surface 300. In one embodiment, the front surface 300 may include a horizontal surface 310, a plurality of protrusions 311, and a seal band 312. The plurality of protrusions 311 and the seal band 312 may protrude upward from the horizontal surface 310. The seal band 312 may be configured in an annular shape to surround the protrusions 311. The seal band 312 may be disposed on the outer periphery of the front surface 300. The protrusions 311 and the seal band 312 may be configured to contact the back surface of the substrate W when the substrate W is electrostatically chucked. A gas outlet may be formed in the horizontal surface 310. The gas outlet may be connected to a heat transfer gas supply unit disposed outside the chamber 10. The heat transfer gas supply unit may be configured to supply a heat transfer gas from a gas outlet into a space formed between the substrate W and the horizontal surface 310, thereby controlling the temperature of the substrate W.

[0063] The electrostatic electrode 1111b may be disposed directly below the surface 300 within the ceramic member 1111a. The electrostatic electrode 1111b may be electrically connected to a DC power supply 350. When a DC voltage from the DC power supply 350 is applied to the electrostatic electrode 1111b, an electrostatic attractive force (Coulomb force) may be generated between the ceramic member 1111a and the substrate W. The substrate W may be attracted to the ceramic member 1111a by the electrostatic attractive force and adsorbed and held on the ceramic member 1111a. The ceramic member 1111a may be an example of a support portion.

[0064] The electrostatic chuck 1111 may further include a heater 360 disposed within the ceramic member 1111a. The heater 360 may be disposed below the electrostatic electrode 1111b within the ceramic member 1111a. In one embodiment, as shown in FIG. 5 , the ceramic member 1111a may be divided into a plurality of divided regions 370 in a plan view, and a heater 360 may be disposed in each of the plurality of divided regions 370. The plurality of divided regions 370 may be divided into a plurality of concentric regions centered on the central axis C1 of the ceramic member 1111a, and each of the concentric regions may be further divided into a plurality of regions in the circumferential direction. That is, the divided region 370 may be divided into a plurality of regions in the radial and circumferential directions. Alternatively, the plurality of divided regions 370 may be formed by dividing the ceramic member 1111a into a grid pattern in a plan view.

[0065] As shown in FIG. 6 , the surface 300 of the ceramic component 1111a may be further divided into a plurality of divided regions 370. The plurality of divided regions 370 may include a central zone 370a including the central axis C1 of the ceramic component 1111a and a plurality of zones 370b arranged in the circumferential direction within the plurality of regions arranged in the radial direction relative to the central axis C1. The plurality of divided regions 370 may be formed by finely dividing the ceramic component 1111a vertically and horizontally into a grid pattern. The number of divided regions 370 may be 50 or more, 100 or more, or 150 or more. One heater 360 may be arranged in each divided region 370, or multiple heaters 360 may be arranged in each divided region 370. The divided regions 370 and heaters 360 may be arranged in multiple rows in the vertical direction. The number and arrangement of the divided regions 370 and heaters 360 in each row may differ from each other. The number of divided regions 370 and heaters 360 may be selected arbitrarily. The ceramic member 1111a may not be divided into multiple regions, but may be a single region.

[0066] 4, the heaters 360 may be electrically connected to a power source 380. The power source 380 may be configured to supply power to the heaters 360 to cause the heaters 360 to generate heat. The power source 380 may be configured to supply a predetermined amount of power to each of the plurality of heaters 360 to cause each heater 360 to generate heat at a predetermined amount.

[0067] The heat flux sensor 200 may be disposed on the rear surface 301 of the ceramic member 1111a. The heat flux sensor 200 may be capable of detecting a heat flux passing through the rear surface 301 of the ceramic member 1111a in the vertical direction. As shown in FIGS. 4 and 7 , a plurality of heat flux sensors 200 may be disposed on the rear surface 301.

[0068] The heat flux sensor 200 may be a magneto-thermoelectric element. In one embodiment, as shown in FIG. 8 , the heat flux sensor 200 may be a magneto-thermoelectric element utilizing the anomalous Nernst effect. The heat flux sensor 200 may be a device that generates a voltage Vq that varies in response to the heat flux Fq, and may generate the voltage Vq in a direction perpendicular to the direction of the heat flux Fq. The heat flux sensor 200 may have a vertical thickness in the range of 0.1 μm to 10 μm.

[0069] The heat flux sensor 200 shown in FIGS. 4 and 7 may be formed by processing the rear surface 301 of the ceramic member 1111a. The processing may include processing the rear surface itself and processing using the rear surface as a base. In one embodiment, the heat flux sensor 200 may be formed by depositing a topological material on the rear surface of the ceramic member 1111a using a film deposition technique, and then forming the topological material film into a predetermined pattern using an etching technique. The film deposition technique may be a sputtering technique. The heat flux sensor 200 may be manufactured elsewhere and attached to the rear surface 301 of the ceramic member 1111a.

[0070] As shown in FIG. 4 , the heat flux sensor 200 may be electrically connected to a sensor control unit 390 disposed outside the ceramic member 1111a. The sensor control unit 390 may be included in the control unit 2 or may be controlled by the control unit 2. In one embodiment, as shown in FIG. 7 , a wiring 400 connected to the heat flux sensor 200 may be formed on the rear surface 301 of the ceramic member 1111a. The wiring 400 may extend from the heat flux sensor 200 to the outer edge of the rear surface 301 of the ceramic member 1111a and have a terminal 400a on a side surface of the ceramic member 1111a. The terminal 400a of the wiring 400 may be electrically connected to the sensor control unit 390 via a lead wire 401. The wiring 400 may be formed together with the heat flux sensor 200 by processing the rear surface 301 of the ceramic member 1111a. In one embodiment, the wiring 400 may be formed by depositing a wiring material on the rear surface of the ceramic member 1111a using a film deposition technique and then etching the film into a predetermined pattern. The film deposition technique may be sputtering. The wiring 400 may be manufactured elsewhere and attached to the rear surface 301 of the ceramic member 1111a.

[0071] In one embodiment, the heat flux sensors 200 may be arranged at positions corresponding to the respective divided regions 370 of the ceramic member 1111a in a plan view. One heat flux sensor 200 may be arranged for each divided region 370, or multiple heat flux sensors 200 may be arranged for each divided region 370. The heat flux sensors 200 may be arranged to correspond to each heater 360. One heat flux sensor 200 may be arranged for each heater 360, or multiple heat flux sensors 200 may be arranged for each heater 360.

[0072] As shown in FIG. 4 , the adhesive layer 201 may be interposed between the base 1110 and the electrostatic chuck 1111. The adhesive layer 201 may have a thickness greater than the vertical thickness of the heat flux sensor 200 and may be configured to cover the heat flux sensor 200 without any gaps. The heat flux sensor 200 may be disposed within the adhesive layer 201 and may not be in contact with the base 1110. The adhesive layer 201 may be made of a material that is electrically insulating and highly thermally conductive. In one example, the adhesive layer 201 may be made primarily of silicone or acrylic. The adhesive layer 201 may have a core material made of a film such as polyimide. The adhesive layer 201 may be made of silicone or acrylic mixed with at least one of alumina particles, aluminum nitride particles, and other substances as a filler to improve thermal conductivity.

[0073] 9 is a flowchart illustrating an example of a method for manufacturing an electrostatic chuck 1111. In one embodiment, the method for manufacturing the electrostatic chuck 1111 may include a step ST1 of forming a ceramic member 1111 a and a step ST2 of forming a heat flux sensor 200 on a back surface of the ceramic member 1111 a.

[0074] In step ST1, protrusions 311 and seal bands 312 may be formed on the surface 300 of the ceramic member 1111a. An electrostatic electrode 1111b and a heater 360 may be formed inside the ceramic member 1111a.

[0075] In step ST2, first, a film of a topological material that serves as a material for generating the anomalous Nernst effect may be formed on the rear surface of the ceramic member 1111a. The film formation may be performed by sputtering. Next, the film of the topological material may be shaped into a predetermined pattern using an etching technique. In one embodiment, a mask with openings may be formed on the film of the topological material, and the film of the topological material may be shaped into a predetermined pattern (such as a dot pattern or a line-and-space pattern) by plasma etching or wet etching. Note that steps ST1 and ST2 may be performed in this order or in the reverse order. Step TS2 may include a step of forming conductive wiring that connects the formed / patterned topological material. After step TS2, a step of processing the ceramic member 1111a may be included.

[0076] <Example of Plasma Processing Method> The plasma processing method performed in the plasma processing apparatus 1 includes an etching process that uses plasma to etch a film on the substrate W. In one embodiment, the plasma processing method is executed by the control unit 2 in the plasma processing apparatus 1.

[0077] First, as shown in Fig. 2, the substrate W is carried into the chamber 10 and placed on the substrate support part 11. The substrate W is attracted and held by the electrostatic chuck 1111 as shown in Fig. 4. At this time, the substrate W is placed on the ceramic member 1111a, and the back surface of the substrate W contacts the protrusions 311 and the seal band 312. A DC voltage is applied to the electrostatic electrode 1111b, generating an electrostatic attractive force between the electrostatic chuck 1111 and the substrate W, and the substrate W is attracted to the electrostatic chuck 1111.

[0078] 2 generates plasma in the plasma processing space 10s. A processing gas is supplied to the shower head 13 by the gas supply unit 20 and then supplied from the shower head 13 to the plasma processing space 10s. The processing gas supplied at this time includes a gas that generates activated species necessary for etching the substrate W.

[0079] One or more RF signals are supplied to the upper electrode and / or the lower electrode from the RF power supply 31. The atmosphere in the plasma processing space 10s is exhausted through the gas exhaust port 10e, and the pressure inside the plasma processing space 10s is reduced. Plasma is generated from the processing gas on the substrate support 11 in the plasma processing space 10s, and the substrate W is etched.

[0080] In the above-described plasma processing, a large amount of heat is generated by the generation of plasma. During the plasma processing, the heat generated by the plasma is also transferred to the substrate W on the substrate support 11. In the base 1110 of the substrate support 11 shown in FIG. 4 , a temperature control medium at a constant temperature flows through the flow path 1110a, and heat Q is transferred from the substrate W through the electrostatic chuck 1111, the adhesive layer 201, and the base 1110 in this order and is then discharged by the temperature control medium. This cools the substrate W and the substrate support 11.

[0081] In the plasma processing, the temperature of the substrate W or the electrostatic chuck 1111 is controlled to a predetermined target temperature. In one embodiment, the power supply 380 supplies power to the heater 360, causing the heater 360 to generate heat and adjust the temperature of the substrate W or the electrostatic chuck 1111.

[0082] In one embodiment, the control unit 2 adjusts the power (voltage, current) supplied from the power supply 380 to the heater 360 based on the heat flux measured by the heat flux sensor 200, thereby controlling the output (heat generation amount) of the heater 360. In one embodiment, the heat flux sensor 200 measures the heat flux Fq of heat Q flowing from the substrate W through the electrostatic chuck 1111 to the base 1110. Based on the value of the heat flux Fq, the control unit 2 estimates the temperature of the substrate W or the electrostatic chuck 1111 in a thermal equilibrium state, and calculates the heat generation amount of the heater 360 required for the substrate W or the electrostatic chuck 1111 to reach a target temperature. The control unit 2 adjusts the power supplied to the heater 360 to control the heat generation amount of the heater 360 (feedforward control).

[0083] The heat generation amount of the heater 360 may be controlled for each divided region 370 of the ceramic member 1111a and for each heater 360. The heat flux may be measured by the heat flux sensor 200 corresponding to each divided region 370, and the heat generation amount of the heater 360 corresponding to each divided region 370 may be controlled based on the heat flux of each divided region 370. The control unit 2 may also estimate the temperature of the substrate W or the electrostatic chuck 1111 based on the heat flux measured by the heat flux sensor 200. The control unit 2 may estimate the amount of heat diffusion in the lateral direction (horizontal direction) from the difference in heat flux between adjacent divided regions 370, and control the heat generation amount of the heater 360 corresponding to each divided region 370.

[0084] According to this exemplary embodiment, the substrate support 11 includes a base 1110 having a flow path 1110a through which a temperature control medium flows, a ceramic member 1111a disposed on the base 1110, and a heat flux sensor 200 disposed on a rear surface 301 of the ceramic member 1111a. By measuring the heat flux at the rear surface 301 of the ceramic member 1111a using the heat flux sensor 200, it is possible to quickly determine the temperatures (heat quantities) of the substrate W and the electrostatic chuck 1111 in a thermal equilibrium state. This allows for quicker temperature control of the substrate W and the electrostatic chuck 1111 than with a temperature feedback control system.

[0085] When a thermal fluctuation occurs, a time lag occurs between the thermal fluctuation and the temperature fluctuation of the substrate or electrostatic chuck 1111 depending on the heat capacity of the substrate, electrostatic chuck 1111, etc. Therefore, when the output of the heater 360 is feedback controlled based on the temperature measured by the temperature sensor, the output of the heater 360 may be excessive or insufficient, and it takes time for the temperature of the substrate or electrostatic chuck 1111 to converge. Therefore, by using the heat flux sensor 200, temperature control can be performed more quickly than when a temperature sensor is used.

[0086] By measuring the heat flux with the heat flux sensor 200, the temperatures of the substrate W and the electrostatic chuck 1111 can be calculated using the known heat capacities of the substrate W and the electrostatic chuck 1111, thereby enabling accurate setting of etching process conditions. Note that in this exemplary embodiment, the heat flux sensor 200 is used to control the heater 360, but it may also be used simply to calculate the temperatures of the substrate W and the electrostatic chuck 1111.

[0087] According to this exemplary embodiment, the heat flux sensor 200 is a magneto-thermoelectric conversion element that utilizes the anomalous Nernst effect, and therefore can detect heat flux even if the thickness of the heat flux sensor 200 is reduced. This allows the heat flux sensor 200 to be made thinner. As a result, the heat flux sensor 200 itself is less likely to disturb the heat flux, making it less likely that an anomalous thermal spot will be formed due to the structure of the sensor, and making it possible to maintain uniformity in the substrate temperature across the surface.

[0088] According to this exemplary embodiment, the heat flux sensor 200 is formed by processing the rear surface 301 of the ceramic member 1111a, and therefore, for example, it is possible to arrange a large number of fine heat flux sensors 200. As a result, even when the ceramic member 1111a has a large number of divided regions 370 each having a heater 360, it is possible to arrange a heat flux sensor for each divided region 370.

[0089] According to this exemplary embodiment, an adhesive layer 201 is disposed between the base 1110 and the ceramic member 1111a, so that even if the heat flux sensor 200 is disposed on the rear surface 301 of the ceramic member 1111a, heat is properly transferred from the ceramic member 1111a to the base 1110.

[0090] According to this exemplary embodiment, the ceramic member 1111a includes the heater 360, and the control unit 2 is configured to control the output of the heater 360 based on the heat flux measured by the heat flux sensor 200. This allows for rapid temperature control of the substrate W and the electrostatic chuck 1111.

[0091] In the above embodiment, an example in which the electrostatic chuck 1111 is used in a capacitively coupled plasma device has been described, but the present invention is not limited to this and may be used in other types of plasma devices. Furthermore, the electrostatic chuck 1111 is not limited to plasma processing devices and may be used in other types of substrate processing devices. The substrate support 11 may not be the electrostatic chuck 1111, but may have a support without a substrate chuck electrode. The heat flux sensor 200 may be a thermoelectric conversion element that utilizes the Seebeck effect.

[0092] Embodiments of the present disclosure further include the following aspects.

[0093] (Supplementary Note 1) A substrate support comprising: a base including a flow path through which a temperature control medium flows; a support portion disposed on the base, the support portion including a front surface for supporting a substrate and a back surface; and a heat flux sensor disposed on the back surface of the support portion.

[0094] (Supplementary Note 2) The substrate support according to Supplementary Note 1, wherein an adhesive layer is disposed between the base and the support.

[0095] (Supplementary Note 3) The substrate support according to Supplementary Note 1 or 2, wherein the heat flux sensor is a magneto-thermoelectric conversion element.

[0096] (Supplementary Note 4) The substrate support according to any one of Supplementary Notes 1 to 3, wherein the heat flux sensor is a magneto-thermoelectric conversion element that utilizes the anomalous Nernst effect.

[0097] (Supplementary Note 5) The substrate support according to any one of Supplementary Notes 1 to 4, wherein the heat flux sensor has a thickness in the range of 0.1 μm to 10 μm.

[0098] (Supplementary Note 6) The substrate support according to any one of Supplementary Notes 1 to 5, wherein the heat flux sensor is formed by processing the rear surface of the support portion.

[0099] (Supplementary Note 7) The substrate support according to any one of Supplementary Notes 1 to 6, wherein the support portion includes a substrate chuck electrode.

[0100] (Supplementary Note 8) The substrate support according to any one of Supplementary Notes 1 to 7, wherein the support includes a heater.

[0101] (Supplementary Note 9) The substrate support according to any one of Supplementary Notes 1 to 8, wherein the support portion includes a plurality of heaters, and one or a plurality of the heat flux sensors are arranged for each of the heaters.

[0102] (Supplementary Note 10) An electrostatic chuck for holding a substrate, comprising: a dielectric body including a front surface for supporting the substrate and a back surface; a substrate chuck electrode disposed within the dielectric body; and a heat flux sensor disposed on the back surface of the dielectric body.

[0103] (Supplementary Note 11) The electrostatic chuck according to Supplementary Note 10, wherein the heat flux sensor is a magneto-thermoelectric conversion element.

[0104] (Supplementary Note 12) The electrostatic chuck according to Supplementary Note 10 or 11, wherein the heat flux sensor is a magneto-thermoelectric conversion element utilizing the anomalous Nernst effect.

[0105] (Supplementary Note 13) The electrostatic chuck according to any one of Supplementary Notes 10 to 12, wherein the heat flux sensor has a thickness in the range of 0.1 μm to 10 μm.

[0106] (Supplementary Note 14) The electrostatic chuck according to any one of Supplementary Notes 10 to 13, wherein the heat flux sensor is formed by processing the back surface of the dielectric body.

[0107] (Supplementary Note 15) The electrostatic chuck according to any one of Supplementary Notes 10 to 14, wherein the dielectric body includes a heater.

[0108] (Supplementary Note 16) The electrostatic chuck according to any one of Supplementary Notes 10 to 15, wherein the dielectric body includes a plurality of heaters, and one or more of the heat flux sensors are arranged for each of the heaters.

[0109] (Supplementary Note 17) A plasma processing apparatus comprising: a chamber; a substrate support disposed within the chamber; a gas supply unit configured to supply a processing gas into the chamber; and a plasma generation unit configured to generate plasma from the processing gas within the chamber, wherein the substrate support comprises: a base including a flow path through which a temperature control medium flows; a support unit disposed on the base, the support unit including a front surface and a back surface for supporting a substrate; and a heat flux sensor disposed on the back surface of the support unit.

[0110] (Supplementary Note 18) The plasma processing apparatus according to Supplementary Note 17, further comprising a control unit, wherein the support unit includes a heater, and the control unit is configured to control an output of the heater based on the heat flux measured by the heat flux sensor.

[0111] (Supplementary Note 19) A method for manufacturing an electrostatic chuck, comprising: forming a dielectric having a front surface for supporting a substrate and a back surface, the dielectric having a substrate chuck electrode disposed within the dielectric; and forming a heat flux sensor on the back surface of the dielectric.

[0112] The above embodiments are described for the purpose of explanation and are not intended to limit the scope of the present disclosure. Various modifications can be made to the above embodiments without departing from the scope and spirit of the present disclosure. For example, some components in one embodiment can be added to other embodiments. Also, some components in one embodiment can be replaced with corresponding components in other embodiments.

[0113] 1: Plasma processing apparatus, 2: Control unit, 10: Chamber, 11: Substrate support unit, 1110: Base, 1110a: Flow path, 1111: Electrostatic chuck, 1111a: Ceramic member, 1111b: Electrostatic electrode, 200: Heat flux sensor, 201: Adhesion layer, 360: Heater, W: Substrate

Claims

1. A substrate support comprising: a base including a flow path through which a temperature control medium flows; a support portion disposed on the base, the support portion including a front surface for supporting a substrate and a back surface; and a heat flux sensor disposed on the back surface of the support portion.

2. The substrate support of claim 1, wherein an adhesive layer is disposed between the base and the support.

3. The substrate support of claim 1, wherein the heat flux sensor is a magneto-thermoelectric element.

4. The substrate support of claim 1, wherein the heat flux sensor is a magneto-thermoelectric conversion element utilizing the anomalous Nernst effect.

5. The substrate support of claim 1, wherein the heat flux sensor has a thickness in the range of 0.1 μm to 10 μm.

6. The substrate support of claim 1, wherein the heat flux sensor is formed by processing the rear surface of the support.

7. The substrate support of claim 1, wherein the support comprises a substrate chuck electrode.

8. The substrate support of claim 1, wherein the support includes a heater.

9. The substrate support of claim 1, wherein the support includes a plurality of heaters, and one or more of the heat flux sensors are disposed for each of the heaters.

10. An electrostatic chuck for holding a substrate, comprising: a dielectric body having a front surface for supporting the substrate and a back surface; a substrate chucking electrode disposed within the dielectric body; and a heat flux sensor disposed on the back surface of the dielectric body.

11. The electrostatic chuck according to claim 10, wherein the heat flux sensor is a magneto-thermoelectric conversion element.

12. The electrostatic chuck according to claim 10, wherein the heat flux sensor is a magneto-thermoelectric conversion element that utilizes the anomalous Nernst effect.

13. The electrostatic chuck of claim 10, wherein the heat flux sensor has a thickness in the range of 0.1 μm to 10 μm.

14. The electrostatic chuck according to claim 10, wherein the heat flux sensor is formed by processing the rear surface of the dielectric body.

15. The electrostatic chuck of claim 10, wherein the dielectric includes a heater.

16. The electrostatic chuck according to claim 10, wherein the dielectric body includes a plurality of heaters, and one or more of the heat flux sensors are disposed for each of the heaters.

17. A plasma processing apparatus comprising: a chamber; a substrate support disposed within the chamber; a gas supply unit configured to supply a processing gas into the chamber; and a plasma generation unit configured to generate plasma from the processing gas within the chamber, wherein the substrate support comprises: a base including a flow path through which a temperature control medium flows; a support unit disposed on the base, the support unit including a front surface for supporting a substrate and a back surface; and a heat flux sensor disposed on the back surface of the support unit.

18. The plasma processing apparatus according to claim 17, further comprising a control unit, wherein the support unit includes a heater, and the control unit is configured to control the output of the heater based on the heat flux measured by the heat flux sensor.

19. A method for manufacturing an electrostatic chuck, comprising: forming a dielectric having a front surface for supporting a substrate and a back surface, the dielectric having a substrate chucking electrode disposed within the dielectric; and forming a heat flux sensor on the back surface of the dielectric.

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