Substrate processing apparatus and electrostatic chuck

Abstract

The electrostatic chuck includes a chuck body portion having an upper surface, at least one first gas supply path, and at least one second gas supply path. A plurality of protrusions, a first annular groove, a second annular groove surrounding the first annular groove, and an annular intermediate groove disposed between the first annular groove and the second annular groove and shallower than the first annular groove and the second annular groove are formed on the upper surface. The first annular groove communicates with the at least one first gas supply path via at least one first gas supply hole, and the second annular groove communicates with the at least one second gas supply path via at least one second gas supply hole.

Description

Technical Field

[0001] The present invention relates to a substrate processing apparatus and an electrostatic chuck. Background Art

[0002] Patent Document 1 discloses that an electrostatic chuck includes a plurality of sealing bands located on the surface of the chuck. The plurality of sealing bands can contact the substrate to form a seal between adjacent cooling bands.

[0003] Patent Document 2 discloses that an outer peripheral ring that annularly surrounds the outermost periphery is provided on the substrate holding surface of the electrostatic chuck. The outer peripheral ring can contact the substrate when the substrate is placed on the substrate holding surface.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2020-512692

[0007] Patent Document 2: Japanese Patent Application Laid-Open No. 2006-257495 Summary of the Invention

[0008] Technical Problem to be Solved by the Invention

[0009] The technology of the present invention can appropriately control the temperature of the substrate and improve the uniformity of plasma processing within the plane of the substrate.

[0010] Means for Solving the Technical Problem

[0011] A substrate processing apparatus according to one aspect of the present invention includes: a substrate processing chamber; a substrate support portion disposed in the substrate processing chamber and having at least one first gas supply path and at least one second gas supply path, the substrate support portion having a base and an electrostatic chuck disposed on the base and having an upper surface on which a plurality of protrusions, a first annular groove, a second annular groove surrounding the first annular groove, and an annular intermediate groove disposed between the first annular groove and the second annular groove and shallower than the first annular groove and the second annular groove are formed, the first annular groove communicating with the at least one first gas supply path through at least one first gas supply hole, the second annular groove communicating with the at least one second gas supply path through at least one second gas supply hole; at least one first control valve capable of controlling the flow rate or pressure of the gas supplied through the at least one first gas supply path; and at least one second control valve capable of controlling the flow rate or pressure of the gas supplied through the at least one second gas supply path.

[0012] Advantages of the Invention

[0013] By adopting the present invention, the temperature of the substrate can be appropriately controlled, and the uniformity of plasma treatment within the plane of the substrate can be improved. Description of the Drawings

[0014] Figure 1 is an explanatory diagram schematically showing the structure of a plasma processing system.

[0015] Figure 2 is a longitudinal sectional view showing an outline of the structure of a plasma processing apparatus.

[0016] Figure 3 is a plan view showing an outline of the structure of an electrostatic chuck according to the first embodiment.

[0017] Figure 4 is a longitudinal sectional view showing an outline of the structure of an electrostatic chuck according to the first embodiment.

[0018] Figure 5 is a sectional perspective view showing an outline of the structure of an electrostatic chuck according to the first embodiment and an explanatory diagram showing the pressure distribution in a heat transfer space.

[0019] Figure 6 is a plan view showing an outline of the structure of an electrostatic chuck according to a modified example of the first embodiment.

[0020] Figure 7 is a plan view showing an outline of the structure of an electrostatic chuck according to the second embodiment.

[0021] Figure 8 is a plan view showing an outline of the structure of an electrostatic chuck according to the second embodiment.

[0022] Figure 9 is a plan view showing an outline of the structure of an electrostatic chuck according to a comparative example.

[0023] Figure 10 is an explanatory diagram showing the effect of the electrostatic chuck according to the second embodiment.

[0024] Figure 11 is a plan view showing an outline of the structure of an electrostatic chuck according to the third embodiment.

[0025] Figure 12 is a sectional perspective view showing an outline of the structure of an electrostatic chuck according to the third embodiment.

[0026] Figure 13 is an explanatory diagram showing an example of physical property values of a porous member according to the third embodiment. Detailed Description of the Invention

[0027] In the manufacturing process of semiconductor devices, for example, a semiconductor substrate (hereinafter referred to as "substrate") is subjected to plasma processing in a plasma processing apparatus. In the plasma processing apparatus, plasma is generated by exciting a processing gas inside a chamber, and the substrate supported by an electrostatic chuck is processed using this plasma.

[0028] In plasma processing, in order to improve the in-plane uniformity of the plasma processing of the substrate, it is required to appropriately control the temperature of the substrate to be processed. Therefore, for example, a heat transfer gas such as helium is supplied to the space between the back surface of the substrate and the front surface of the electrostatic chuck, and the temperature of the substrate is controlled by controlling the pressure of this heat transfer gas.

[0029] In addition, in recent years, in order to cope with further high-precision temperature control of the substrate, the space between the back surface of the above-mentioned substrate and the front surface of the electrostatic chuck is divided into a plurality of regions, and a pressure difference of the heat transfer gas is provided between the regions to control the temperature of the substrate for each region. Conventionally, in order to control the pressure of the heat transfer gas for each region, for example, a partition member that is in direct contact with the back surface of the substrate and is called a so-called sealing band is provided on the front surface of the electrostatic chuck. For example, a structure in which a plurality of sealing bands are provided on the front surface of the electrostatic chuck is disclosed in the above-mentioned Patent Document 1. In addition, the above-mentioned Patent Document 2 discloses that an inner peripheral ring can be provided on the front surface of the electrostatic chuck inside the outermost peripheral ring.

[0030] However, since the sealing band is in direct contact with the back surface of the substrate, the contact portion becomes a local temperature singularity. Specifically, heat transfer occurs between the contact portion and the substrate, and the temperature of the substrate at the contact portion decreases. The temperature singularity of the substrate affects the rate of plasma processing, and as a result, there is a case where the plasma processing cannot be performed uniformly in the plane of the substrate. Therefore, there is room for improvement in conventional plasma processing.

[0031] The technology of the present invention has been completed in view of the above circumstances, and can appropriately control the temperature of the substrate and improve the uniformity of plasma processing in the plane of the substrate. Hereinafter, the plasma processing apparatus and the electrostatic chuck of the present embodiment will be described with reference to the drawings. In addition, in this specification and the drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and repeated description is omitted.

[0032] <Plasma Processing System>

[0033] First, a plasma processing system according to an embodiment will be described. Figure 1 This is a diagram for explaining a structural example of a plasma processing system.

[0034] In one embodiment, a 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 as a substrate processing chamber, a substrate support portion 11, and a plasma generation portion 12. The plasma processing chamber 10 has a plasma processing space. In addition, the plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas discharge port for discharging gas from the plasma processing space. The gas supply port is connected to a gas supply portion 20 described later, and the gas discharge port is connected to an exhaust system 40 described later. The substrate support portion 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0035] The plasma generation portion 12 can generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), ECR plasma (Electron-Cyclotron-Resonance Plasma), helicon wave plasma (HWP), surface wave plasma (SWP), or the like. In addition, various types of plasma generation portions including an AC (Alternating Current) plasma generation portion and a DC (Direct Current) plasma generation portion may be used. In one embodiment, the AC signal (AC electric power) used in the AC plasma generation portion has a frequency in the range of 100 kHz to 10 GHz. Therefore, the AC signal includes an RF (Radio Frequency) signal and a microwave signal. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0036] The control unit 2 can process computer-executable commands for causing the plasma processing apparatus 1 to execute various processes described in the present invention. The control unit 2 can control each element of the plasma processing apparatus 1 to execute 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 can be implemented by a computer 2a, for example. The processing unit 2a1 can read a program from the storage unit 2a2 and execute various control actions by executing the read program. The program may be pre-stored in the storage unit 2a2 or may be obtained via a medium when needed. The obtained program is stored in the storage unit 2a2 and read and executed by the processing unit 2a1 from the storage unit 2a2. 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 RAM (Random Access Memory), a ROM (Read Only Memory), an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 can communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

[0037] <Plasma Processing Apparatus>

[0038] Next, a structural example of a capacitively coupled plasma processing apparatus, which is an example of the plasma processing apparatus 1, will be described. Figure 2 It is a diagram for explaining a structural example of a capacitively coupled plasma processing apparatus.

[0039] 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. In addition, the plasma processing apparatus 1 includes a substrate support portion 11 and a gas introduction portion. The gas introduction portion can introduce at least one processing gas into the plasma processing chamber 10. The gas introduction portion includes a shower head 13. The substrate support portion 11 is disposed in the plasma processing chamber 10. The shower head 13 is disposed above the substrate support portion 11. In one embodiment, the shower head 13 constitutes at least a part of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13, the side wall 10a of the plasma processing chamber 10, and the substrate support portion 11. The plasma processing chamber 10 is grounded. The shower head 13 and the substrate support portion 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0040] The substrate support portion 11 includes a support main body portion 111 and a ring assembly 112. The upper surface of the support main body portion 111 has: a substrate support surface 111a as a central region for supporting the substrate W; and a ring support surface 111b as a ring-shaped region for supporting the ring assembly 112. A wafer is an example of the substrate W. The ring support surface 111b of the support main body portion 111 surrounds the substrate support surface 111a of the support main body portion 111 in a plan view. The substrate W is disposed on the substrate support surface 111a of the support main body portion 111, and the ring assembly 112 is disposed on the ring support surface 111b of the support main body portion 111 so as to surround the substrate W on the substrate support surface 111a of the support main body portion 111.

[0041] In one embodiment, the support main body portion 111 includes a base 113 and an electrostatic chuck 114. The base 113 includes a conductive member. The conductive member of the base 113 can function as a lower electrode. The electrostatic chuck 114 is disposed on the base 113. The electrostatic chuck 114 includes a chuck main body portion 200 and an electrostatic electrode 201 disposed within the chuck main body portion 200. The chuck main body portion 200 has a substrate support surface 111a. In one embodiment, the chuck main body portion 200 further has an annular support surface 111b. Alternatively, other components surrounding the electrostatic chuck 114, such as an annular electrostatic chuck or an annular insulating member, may have the annular support surface 111b. In this case, the annular assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 114 and the annular insulating member. Additionally, at least one RF / DC electrode coupled to an RF power supply 31 and / or a DC power supply 32 described later may be disposed within the chuck main body portion 200. 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 referred to as a bias electrode. Further, the conductive member of the base 113 and the at least one RF / DC electrode may function as a plurality of lower electrodes. Additionally, the electrostatic electrode 201 may function as a lower electrode. Accordingly, the substrate support portion 11 includes at least one lower electrode.

[0042] The annular 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 material or an insulating material, and the cover ring is formed of an insulating material.

[0043] In addition, the substrate support portion 11 may include a temperature adjustment module for adjusting at least one of the electrostatic chuck 114, the annular assembly 112, and the substrate W to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow path 120, or a combination thereof. A heat transfer fluid such as brine or gas may flow through the flow path 120. In one embodiment, the flow path 120 is formed within the base 113, and one or more heaters are disposed within the chuck main body portion 200 of the electrostatic chuck 114. Additionally, the substrate support portion 11 may include a heat transfer gas supply portion for supplying a heat transfer gas to a gap between the back surface of the substrate W and the substrate support surface 111a.

[0044] The showerhead 13 can introduce at least one processing 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 a plurality of gas introduction ports 13c. The processing gas supplied to the gas supply port 13a can be introduced into the plasma processing space 10s from the plurality of gas introduction ports 13c through the gas diffusion chamber 13b. In addition, the showerhead 13 includes at least one upper electrode. Furthermore, in addition to the showerhead 13, the gas introduction unit may further include one or more side gas injectors (SGI: Side Gas Injector) installed in one or more openings formed in the side wall 10a.

[0045] 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 can supply at least one processing gas from the respective corresponding gas source 21 to the showerhead 13 via the respective corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Moreover, the gas supply unit 20 may include at least one flow modulation device for modulating or pulsing the flow rate of at least one processing gas.

[0046] 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 can supply at least one RF signal (RF electric power) to at least one lower electrode and / or at least one upper electrode. Thereby, plasma can be formed 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. In addition, by supplying a bias RF signal to at least one lower electrode, a bias potential can be generated on the substrate W, and the ion component in the formed plasma can be attracted to the substrate W.

[0047] In one embodiment, the RF power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation 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 can generate a source RF signal (source RF electric 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 generation unit 31a may be able to generate a plurality of 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.

[0048] The second RF generation unit 31b is coupled to at least one lower electrode via at least one impedance matching circuit and can generate a bias RF signal (bias RF electric 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, it may be that the second RF generation unit 31b can generate a plurality of bias RF signals having different frequencies. The one or more generated bias RF signals are supplied to at least one lower electrode. Additionally, in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0049] Additionally, the power supply 30 may include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generation unit 32a and a second DC generation unit 32b. In one embodiment, the first DC generation unit 32a is connected to at least one lower electrode and can generate a first DC signal. The generated first DC signal is applied to at least one lower electrode. In one embodiment, the second DC generation unit 32b is connected to at least one upper electrode and can generate a second DC signal. The generated second DC signal is applied to at least one upper electrode.

[0050] In various embodiments, the first DC signal and the second DC signal 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 pulse may have a pulse waveform in the shape of a rectangle, trapezoid, triangle, or a combination thereof. In one embodiment, a waveform generation unit for generating a sequence of voltage pulses from the DC signal is connected between the first DC generation unit 32a and at least one lower electrode. Thus, the first DC generation unit 32a and the waveform generation unit constitute a voltage pulse generation unit. When the second DC generation unit 32b and the waveform generation unit constitute a voltage pulse generation unit, the voltage pulse generation unit is connected to at least one upper electrode. The voltage pulse may have a positive polarity or a negative polarity. Additionally, the sequence of voltage pulses may include one or more positive-polarity voltage pulses and one or more negative-polarity voltage pulses within one cycle. Additionally, it may be that in addition to the RF power supply 31, the first DC generation unit 32a and the second DC generation unit 32b are provided, or it may be that the first DC generation unit 32a is provided in place of the second RF generation unit 31b.

[0051] The exhaust system 40 can be connected, for example, to a gas outlet 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 can be regulated by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0052] <Plasma Processing Method>

[0053] Next, the plasma processing performed using the plasma processing system configured as described above will be described. As the plasma processing, for example, an etching process or a film forming process is performed.

[0054] First, the substrate W is fed into the interior of the plasma processing chamber 10, and the substrate W is placed on the electrostatic chuck 114. Then, by applying a DC voltage to the electrostatic electrode 201 of the electrostatic chuck 114, the substrate W is electrostatically adsorbed and held on the electrostatic chuck 114 by Coulomb force. At this time, the substrate W is adjusted to a desired temperature. In addition, after the substrate W is fed, the interior of the plasma processing chamber 10 is decompressed to a desired degree of vacuum using the exhaust system 40.

[0055] Next, a processing gas is supplied from the gas supply unit 20 to the plasma processing space 10s via the shower head 13. In addition, a source RF electric power for plasma generation is supplied to the conductive member of the substrate support portion 11 and / or the conductive member of the shower head 13 by the first RF generation unit 31a of the RF power supply 31. Thus, the processing gas can be excited to generate plasma. At this time, a bias RF signal for ion attraction can be supplied by the second RF generation unit 31b. Thus, the plasma processing can be performed on the substrate W by the action of the generated plasma.

[0056] <First Embodiment>

[0057] Next, the structure of the electrostatic chuck 114 of the first embodiment will be described. Figure 3 is a plan view showing an outline of the structure of the electrostatic chuck 114. Figure 4 is a longitudinal sectional view showing an outline of the structure of the electrostatic chuck 114. In addition, in Figure 4 C represents the center line of the electrostatic chuck 114.

[0058] As Figure 3 and Figure 4As shown, the electrostatic chuck 114 has a chuck body portion 200. The chuck body portion 200 is made of a dielectric, for example, formed of a ceramic such as alumina (Al2O3). The electrostatic chuck 114 has a substantially disc shape. Inside the chuck body portion 200, an electrostatic electrode 201 connected to the first DC generation unit 32a is provided, for example. By applying a DC voltage from the first DC generation unit 32a to the electrostatic electrode 201, a Coulomb force is generated, and the electrostatic chuck 114 can adsorb the substrate W. In addition, a heater (not shown) may be provided inside the chuck body portion 200.

[0059] The upper surface of the chuck body portion 200 has a substrate support surface 111a for supporting the substrate W. The substrate support surface 111a is formed, for example, as a circle having a diameter smaller than that of the supported substrate W. Thus, when the substrate W is supported by the substrate support surface 111a, the outer peripheral portion of the substrate W protrudes outward from the end of the substrate support surface 111a.

[0060] The substrate support surface 111a of the chuck body portion 200 has: a plurality of substrate contact portions 210 as protrusions; and an outer peripheral contact portion 211 as an outer peripheral protrusion. The substrate contact portions 210 are points having a cylindrical shape and are provided protruding from the substrate support surface 111a. The plurality of substrate contact portions 210 are provided inside the outer peripheral contact portion 211. The outer peripheral contact portion 211 protrudes from the substrate support surface 111a at the outermost peripheral portion of the substrate support surface 111a and is provided in a ring shape. That is, the outer peripheral contact portion 211 is arranged so as to surround (enclose) the first annular groove 220a, the second annular groove 220b, and the intermediate groove 240 described later. The plurality of substrate contact portions 210 and the outer peripheral contact portion 211 are formed to have the same height and flat upper surfaces and can contact the substrate W when the substrate W is supported by the electrostatic chuck 114. Therefore, the substrate W can be supported by the plurality of substrate contact portions 210 and the outer peripheral contact portion 211.

[0061] At least one annular groove 220 is formed in the substrate support surface 111a of the chuck body portion 200, and in this embodiment, two annular grooves 220a and 220b are formed. The annular grooves 220a and 220b are each recessed from the substrate support surface 111a to form a ring shape, and in this embodiment, they are formed as circular rings. The annular grooves 220a and 220b are arranged in order from the inside to the outside in the radial direction, and the second annular groove 220b is arranged so as to surround the first annular groove 220a. The center positions of the annular grooves 220a and 220b in a top view are the same as the center position of the substrate support surface 111a, that is, the annular grooves 220a and 220b are arranged on concentric circles.

[0062] The annular grooves 220a and 220b each have a rectangular shape when viewed in cross-section. The cross-sectional shapes of the annular grooves 220a and 220b are the same. In the following description, the annular grooves 220a and 220b are sometimes collectively referred to as the annular groove 220.

[0063] As Figure 5 shown, the depth D1 of the annular groove 220 (the depth from the substrate support surface 111a to the bottom of the annular groove 220) is greater than or equal to the height H1 of the substrate contact portion 210 (the height from the substrate support surface 111a to the upper surface of the substrate contact portion 210). In addition, the depth D2 of the annular groove 220 (the depth from the upper surface of the substrate contact portion 210 to the bottom of the annular groove 220) is more than twice the height H1 of the substrate contact portion 210. For example, the height H1 of the substrate contact portion 210 is 5 μm to 20 μm, and the depth D2 of the annular groove 220 is 10 μm to 40 μm.

[0064] The upper limit values of the depths D1 and D2 of the annular groove 220 are not particularly limited. For example, the annular groove 220 may extend vertically downward such that its bottom does not reach the electrostatic electrode 201 and is located slightly above the upper surface of the electrostatic electrode 201. In addition, for example, the depth D1 of the annular groove 220 may be less than or equal to half of the distance H2 from the upper surface of the substrate contact portion 210 to the upper surface of the electrostatic electrode 201.

[0065] The width E1 of the annular groove 220 is, for example, 0.3 mm to 10 mm. In addition, the width E1 of the annular groove 220 is not particularly limited.

[0066] As Figure 3 and Figure 4As shown, at least one first heat transfer gas supply hole 230a serving as a first gas supply hole is formed in the first annular groove 220a. The first heat transfer gas supply hole 230a is formed to penetrate the chuck body portion 200 from the bottom of the first annular groove 220a. At least one first heat transfer gas supply path 231a serving as a first gas supply path is connected to the first heat transfer gas supply hole 230a, and the first heat transfer gas supply path 231a communicates with the heat transfer gas supply source 232. In the first heat transfer gas supply path 231a, at least one first control valve 233a and a first pressure gauge 234a are provided starting from the heat transfer gas supply source 232 side. The opening degree of the first control valve 233a can be controlled so that the pressure detected by the first pressure gauge 234a becomes the required pressure. Thus, the first control valve 233a can control the flow rate or pressure of the heat transfer gas supplied from the heat transfer gas supply source 232 via the first heat transfer gas supply path 231a. Additionally, the first control valve 233a and the first pressure gauge 234a may be integrally provided. The heat transfer gas supplied from the heat transfer gas supply source 232 can be supplied to the first annular groove 220a via the first heat transfer gas supply path 231a and the first heat transfer gas supply hole 230a, and diffuses in the circumferential direction along the first annular groove 220a. Additionally, the heat transfer gas can also be supplied to the space (hereinafter referred to as "heat transfer space") between the back surface of the substrate W and the substrate support surface 111a.

[0067] At least one second heat transfer gas supply hole 230b serving as a second gas supply hole is formed in the second annular groove 220b. The second heat transfer gas supply hole 230b is formed to penetrate the chuck body portion 200 from the bottom of the second annular groove 220b. At least one second heat transfer gas supply path 231b serving as a second gas supply path is connected to the second heat transfer gas supply hole 230b, and the second heat transfer gas supply path 231b communicates with the heat transfer gas supply source 232. In the second heat transfer gas supply path 231b, at least one second control valve 233b and a second pressure gauge 234b are provided starting from the heat transfer gas supply source 232 side. The second control valve 233b and the second pressure gauge 234b respectively have the same structure as the first control valve 233a and the first pressure gauge 234a, and the second control valve 233b can control the flow rate or pressure of the heat transfer gas. Similarly to the first annular groove 220a, the heat transfer gas supplied from the heat transfer gas supply source 232 via the second heat transfer gas supply path 231b and the second heat transfer gas supply hole 230b can diffuse in the circumferential direction along the second annular groove 220b, and can also be supplied to the heat transfer space.

[0068] In addition, in the present embodiment, the heat transfer gas supply paths 231a and 231b merge and communicate with a common heat transfer gas supply source 232, but they may also communicate with separate heat transfer gas supply sources respectively. Further, in the present embodiment, control valves 233a and 233b are used to control the flow rate or pressure of the heat transfer gas supplied from the heat transfer gas supply holes 230a and 230b. However, in addition to this, the flow rate or pressure of the heat transfer gas may also be controlled by changing the diameters of the heat transfer gas supply holes 230a and 230b. Further, as the heat transfer gas (backside gas), helium gas can be used, for example. Further, in the following description, the heat transfer gas supply holes 230a and 230b may be collectively referred to as the heat transfer gas supply hole 230, the heat transfer gas supply paths 231a and 231b may be collectively referred to as the heat transfer gas supply path 231, the control valves 233a and 233b may be collectively referred to as the control valve 233, and the pressure gauges 234a and 234b may be collectively referred to as the pressure gauge 234.

[0069] On the substrate support surface 111a of the chuck body portion 200, an intermediate groove 240 that functions as a pressure adjustment groove is formed as described later. The intermediate groove 240 is recessed from the substrate support surface 111a and formed in a ring shape, and is formed in a circular ring shape in the present embodiment. The intermediate groove 240 is disposed between the first annular groove 220a and the second annular groove 220b. The center position of the intermediate groove 240 in a plan view is the same as the center position of the substrate support surface 111a, that is, the annular grooves 220a and 220b and the intermediate groove 240 are disposed on concentric circles.

[0070] The intermediate groove 240 has a rectangular shape when viewed in cross section. As Figure 5 shown, the depth D3 of the intermediate groove 240 (the depth from the upper surface of the substrate contact portion 210 to the bottom of the intermediate groove 240) is smaller than the depth D2 of the annular groove 220 (the depth from the upper surface of the substrate contact portion 210 to the bottom of the annular groove 220). For example, the height H1 of the substrate contact portion 210 is 5 μm to 20 μm, and the depth D3 of the intermediate groove 240 is 10 μm to 30 μm.

[0071] The width E2 of the intermediate groove 240 is equal to or greater than the width E1 of the annular groove 220. For example, the width E2 of the intermediate groove 240 is 10 mm to 50 mm. In addition, the width E2 of the intermediate groove 240 is not particularly limited.

[0072] As Figure 3 and Figure 4As shown, the substrate support surface 111a is divided into seven regions R1 to R7 by the annular grooves 220a, 220b and the intermediate groove 240. The first region R1 is a circular region radially inside the first annular groove 220a. The second region R2 is an annular region in which the first annular groove 220a is formed. The third region R3 is an annular region between the first annular groove 220a and the intermediate groove 240. The fourth region R4 is an annular region in which the intermediate groove 240 is formed. The fifth region R5 is an annular region between the intermediate groove 240 and the second annular groove 220b. The sixth region R6 is an annular region in which the second annular groove 220b is formed. The seventh region R7 is an annular region between the second annular groove 220b and the outer peripheral contact portion 211. The above-described plurality of substrate contact portions 210 are arranged in each of the regions R1, R3, R5, and R7.

[0073] For example, when the pressures of the heat transfer gases supplied from the heat transfer gas supply holes 230a and 230b are different, the pressure in the heat transfer space can be controlled for each of the seven regions R1 to R7. Figure 5 is an explanatory diagram showing the pressures in the heat transfer spaces of the regions R1 to R7 when the pressure P2 of the heat transfer gas from the second heat transfer gas supply hole 230b is higher than the pressure P1 of the heat transfer gas from the first heat transfer gas supply hole 230a. In addition, in Figure 5 the figure, the vertical axis represents the pressure in the heat transfer space, and the horizontal axis represents the radial position in a specific direction of the substrate W.

[0074] The heat transfer gas diffuses from the first heat transfer gas supply hole 230a into the heat transfer spaces radially inside the first annular groove 220a, that is, the heat transfer spaces of the first region R1 and the second region R2. Then, the pressures in the heat transfer spaces of these first region R1 and second region R2 become substantially the same as the pressure P1 of the heat transfer gas from the first heat transfer gas supply hole 230a.

[0075] The heat transfer gas diffuses from the second heat transfer gas supply hole 230b into the heat transfer spaces radially outside the second annular groove 220b, that is, the heat transfer spaces of the sixth region R6 and the seventh region R7. Then, the pressures in the heat transfer spaces of these sixth region R6 and seventh region R7 become substantially the same as the pressure P2 of the heat transfer gas from the second heat transfer gas supply hole 230b.

[0076] As described above, the heat transfer gas diffuses circumferentially along the first annular groove 220a, and the heat transfer gas diffuses circumferentially along the second annular groove 220b. A pressure difference is generated due to a decrease in gas conductance in the heat transfer space between the heat transfer spaces of regions R3 to R5 between the first annular groove 220a and the second annular groove 220b and the heat transfer spaces of regions R1 and R2 on the radially inner side. Similarly, a pressure difference is also generated due to a decrease in gas conductance in the heat transfer space between the heat transfer spaces of regions R3 to R5 and the heat transfer spaces of regions R6 and R7 on the radially outer side. That is, the pressure in the heat transfer space of regions R3 to R5 changes from P2 to P1 from the radially outer side toward the inner side.

[0077] An intermediate groove 240 is formed in the fourth region R4. By using this intermediate groove 240, the radial change (hereinafter referred to as "pressure gradient") of the pressure in the heat transfer space is small or becomes substantially constant. That is, in regions R3 to R5, from the radially outer side toward the inner side, the pressure gradient is large in the heat transfer space of the fifth region R5, the pressure gradient is small in the heat transfer space of the fourth region R4, and the pressure gradient is large in the heat transfer space of the third region R3.

[0078] As described above, according to the present embodiment, a pressure difference can be generated between the heat transfer spaces of regions R3 to R5 and the heat transfer spaces of regions R1 and R2, and a pressure difference can also be generated between the heat transfer spaces of regions R3 to R5 and the heat transfer spaces of regions R6 and R7. As a result, the pressure in the heat transfer spaces of regions R1 to R7 can be controlled, and thus the temperature of the substrate W can be controlled for each of regions R1 to R7. At this time, by forming the annular grooves 220a and 220b, the above-described pressure difference can be generated without contacting the substrate W. Therefore, local temperature singularities generated in the case where the sealing tape contacts the substrate as in the past do not occur. Therefore, according to the present embodiment, the temperature controllability of the substrate W can be improved, and the uniformity of plasma processing within the substrate surface can be improved.

[0079] In addition, as described above according to the present embodiment, when the substrate support surface 111a is divided into regions R1 to R7, it does not contact the substrate W. Therefore, it does not change in shape due to consumption like the conventional sealing tape. Therefore, temporal changes are less likely to occur, and the pressure in the heat transfer spaces of regions R1 to R7 can be appropriately controlled.

[0080] Here, when the intermediate groove 240 is not formed in the regions R3 to R5, the pressure in the heat transfer space of the regions R3 to R5 will have a certain pressure gradient from the radially outer side to the inner side. Regarding this point, according to the present embodiment, since the intermediate groove 240 is formed in the fourth region R4 among the regions R3 to R5, the flow of the heat transfer gas can be changed in the intermediate groove 240, and the pressure gradient in the heat transfer space in the fourth region R4 can be reduced. Therefore, the radial pressure distribution in the heat transfer space can be controlled more precisely. As a result, the temperature controllability of the substrate W can be further improved, and the uniformity of plasma processing within the substrate surface can be further improved.

[0081] In the simulation, as a comparative example, when the intermediate groove 240 is not formed in the regions R3 to R5, the pressure gradient in the heat transfer space in the regions R3 to R5 cannot be controlled. On the other hand, as an example, when the position of the intermediate groove 240 is changed and set in the regions R3 to R5, even when the pressure conditions of the heat transfer gas supplied from the heat transfer gas supply holes 230a and 230b are the same, the pressure gradient in the heat transfer space can be controlled according to the position of the intermediate groove 240.

[0082] Moreover, in the regions R3 to R5, it is not necessary to form the annular grooves 220 similar to the annular grooves 220a and 220b. Therefore, supply systems such as the heat transfer gas supply paths 231, the control valves 233, and the pressure gauges 234 for supplying the heat transfer gas to the annular grooves 220 are not required. Therefore, the temperature controllability of the substrate W can be improved by forming a simple structure such as the intermediate groove 240.

[0083] In addition, the pressure gradient in the heat transfer space of the fourth region R4 can be controlled by the depth D3 of the intermediate groove 240. For example, when the depth D3 of the intermediate groove 240 is large, the pressure gradient in the heat transfer space of the fourth region R4 becomes small. On the other hand, for example, when the depth D3 of the intermediate groove 240 is small, the pressure gradient in the heat transfer space of the fourth region R4 becomes large. Then, the pressure gradient in the heat transfer space of the fourth region R4 can be determined according to the specifications required for the substrate W, and the depth D3 of the intermediate groove 240 can be determined.

[0084] In addition, it is known that when the depth D3 of the intermediate groove 240 is about half of the depth D2 of the annular groove 220 as in the present embodiment, the effect of the intermediate groove 240 described above, that is, the effect of being able to control the pressure gradient in the heat transfer space of the fourth region R4 to be small enough, can be exerted.

[0085] In addition, in the present embodiment, the depth D3 of the intermediate groove 240 is smaller than the depth D2 of the annular groove 220, but the depth D3 of the intermediate groove 240 may be the same as the depth D2 of the annular groove 220. In this case, the above-described effect, that is, the effect of controlling the pressure gradient of the heat transfer space in the fourth region R4, can also be achieved. In addition, the upper limit value of the depth D3 of the intermediate groove 240 is not particularly limited, but when the depth D3 is too large, abnormal discharge may occur. Therefore, it is preferable that the depth D3 is such that such abnormal discharge can be suppressed.

[0086] In addition, the pressure gradient of the heat transfer space in the fourth region R4 is also affected by the width E2 of the intermediate groove 240. For example, when the width E2 of the intermediate groove 240 is small, the pressure gradient of the heat transfer space in the fourth region R4 becomes large. On the other hand, for example, when the width E2 of the intermediate groove 240 is large, the pressure gradient of the heat transfer space in the fourth region R4 becomes small.

[0087] In addition, according to the present embodiment, since the heat transfer gas diffuses in the circumferential direction in the annular grooves 220a and 220b, the circumferential temperature uniformity of the substrate W can also be improved.

[0088] In addition, according to the present embodiment, since the outer peripheral contact portion 211 that contacts the substrate W is provided at the outermost peripheral portion of the substrate support surface 111a, even if the heat transfer gas is supplied to the heat transfer space radially inside the outer peripheral contact portion 211, it is possible to suppress the outflow of the heat transfer gas to the outside of the heat transfer space.

[0089] <Modification Example of the First Embodiment>

[0090] In the electrostatic chuck 114 of the above-described embodiment, it may be as shown in Figure 5 such that the substrate contact portion 210 is provided in the intermediate groove 240. In this case, even when, for example, the width E2 of the intermediate groove 240 is large, the substrate W can be appropriately supported by the substrate contact portion 210.

[0091] On the substrate support surface 111a of the electrostatic chuck 114 of the above-described embodiment, the circular intermediate groove 240 is formed between the first annular groove 220a and the second annular groove 220b, but the number, arrangement, and shape of the intermediate grooves 240 are not limited thereto.

[0092] For example, it may be as shown in Figure 6As shown, on the substrate support surface 111a, a first intermediate groove 240a is formed between the first annular groove 220a and the second annular groove 220b, and a second intermediate groove 240b is formed radially outside the second annular groove 220b. Alternatively, on the substrate support surface 111a, an intermediate groove 240 may not be formed between the first annular groove 220a and the second annular groove 220b, and only an annular intermediate groove 240 may be formed radially outside the second annular groove 220b. In other words, the intermediate groove 240 may be formed on the inner peripheral side of the annular groove 220 or on the outer peripheral side.

[0093] Alternatively, on the substrate support surface 111a, a plurality of intermediate grooves 240 may be formed between the first annular groove 220a and the second annular groove 220b. Similarly, on the substrate support surface 111a, a plurality of intermediate grooves 240 may be formed radially outside the second annular groove 220b. As described above, any number and configuration of the intermediate grooves 240 can achieve the same effect as the above-described embodiment, that is, the pressure gradient of the heat transfer space in the region where the intermediate groove 240 is formed can be controlled.

[0094] In the above-described embodiment, the intermediate groove 240 has a rectangular shape when viewed in cross section, but the cross-sectional shape of the intermediate groove 240 is not limited thereto. For example, the intermediate groove 240 may have a pentagonal shape when viewed in cross section, and the bottom of the intermediate groove 240 may protrude in the vertical direction. Alternatively, the bottom surface of the intermediate groove 240 may protrude and bend in the vertical direction. In either case, the effect of the intermediate groove 240 described above can be obtained.

[0095] In the above-described embodiment, the intermediate groove 240 is formed in an annular shape, but the planar shape of the intermediate groove 240 is not limited thereto, as long as it is annular. The intermediate groove 240 may also be a polygonal shape or a center-asymmetric shape different from the center position of the substrate support surface 111a. In either case, the effect of the intermediate groove 240 described above can be obtained.

[0096] In the above-described embodiment, the intermediate groove 240 is a continuous ring, but it may be partially discontinuous. In this case, it may be discontinuous at one place or at multiple places of the intermediate groove 240. As described above, the intermediate groove 240 may be composed of a plurality of segments divided in the circumferential direction, and as long as the intermediate groove 240 is formed in an annular shape as a whole, the effect of the intermediate groove 240 described above can be obtained.

[0097] In the substrate support surface 111a of the above-described embodiment, a first annular groove 220a and a second annular groove 220b are formed, but the number, configuration, and shape of the annular grooves 220 are not limited thereto.

[0098] <Second Embodiment>

[0099] Next, the structure of the electrostatic chuck 114 of the second embodiment will be described. In the second embodiment, the arrangement of the plurality of heat transfer gas supply holes 230 in the plurality of annular grooves 220 is optimized.

[0100] Figure 7 An example is shown in which two annular grooves 220, i.e., a first annular groove 220a and a second annular groove 220b, are formed on the substrate support surface 111a. In addition, in Figure 7 , for ease of explanation, the illustration of the substrate contact portion 210 is omitted. The first annular groove 220a and the second annular groove 220b are arranged in order from the inside to the outside in the radial direction and are arranged in a concentric circle pattern. In the first annular groove 220a, a plurality of, for example, six first heat transfer gas supply holes 230a1 to 230a6 are formed at equal intervals in the circumferential direction. In the second annular groove 220b, a plurality of, for example, six second heat transfer gas supply holes 230b1 to 230b6 are formed at equal intervals in the circumferential direction.

[0101] The first heat transfer gas supply holes 230a are arranged at positions equidistant from two second heat transfer gas supply holes 230b arranged adjacent to each other in the circumferential direction. For example, the first heat transfer gas supply hole 230a1 is arranged at a position at an equal distance L1 from the second heat transfer gas supply hole 230b1 and the second heat transfer gas supply hole 230b2 arranged adjacent to each other in the circumferential direction. Similarly, the second heat transfer gas supply holes 230b are arranged at positions equidistant from two first heat transfer gas supply holes 230a arranged adjacent to each other in the circumferential direction. In addition, in the following description, the arrangement of the heat transfer gas supply holes 230a and 230b like this may be referred to as an equidistant arrangement. In this case, the six first heat transfer gas supply holes 230a1 to 230a6 and the six second heat transfer gas supply holes 230b1 to 230b6 are arranged in a so-called staggered pattern.

[0102] In addition, Figure 8 An example is shown in which three annular grooves 220, i.e., a first annular groove 220a, a second annular groove 220b, and a third annular groove 220c, are formed on the substrate support surface 111a. In addition, in Figure 8In order to facilitate the description, the illustration of the substrate contact portion 210 is also omitted. The first annular groove 220a, the second annular groove 220b, and the third annular groove 220c are arranged in order from the inside to the outside in the radial direction, and are arranged in a concentric circle shape. In the first annular groove 220a, a plurality of, for example, six first heat transfer gas supply holes 230a1 to 230a6 are formed at equal intervals in the circumferential direction. In the second annular groove 220b, a plurality of, for example, six second heat transfer gas supply holes 230b1 to 230b6 are formed at equal intervals in the circumferential direction. In the third annular groove 220c, a plurality of, for example, six third heat transfer gas supply holes 230c1 to 230c6 are formed at equal intervals in the circumferential direction.

[0103] The first heat transfer gas supply holes 230a are arranged at positions equidistant from two second heat transfer gas supply holes 230b arranged adjacent to each other in the circumferential direction. For example, the first heat transfer gas supply hole 230a1 is arranged at a position equidistant from the second heat transfer gas supply hole 230b1 and the second heat transfer gas supply hole 230b2 arranged adjacent to each other in the circumferential direction by an equal distance L2. Similarly, the second heat transfer gas supply holes 230b are arranged at positions equidistant from two first heat transfer gas supply holes 230a arranged adjacent to each other in the circumferential direction.

[0104] The second heat transfer gas supply holes 230b are arranged at positions equidistant from two third heat transfer gas supply holes 230c arranged adjacent to each other in the circumferential direction. For example, the second heat transfer gas supply hole 230b1 is arranged at a position equidistant from the third heat transfer gas supply hole 230c1 and the third heat transfer gas supply hole 230c2 arranged adjacent to each other in the circumferential direction by an equal distance L3. Similarly, the third heat transfer gas supply holes 230c are arranged at positions equidistant from two second heat transfer gas supply holes 230b arranged adjacent to each other in the circumferential direction.

[0105] As described above, the heat transfer gas supply holes 230a, 230b, and 230c are arranged at equal distances. In this case, the six first heat transfer gas supply holes 230a1 to 230a6, the six second heat transfer gas supply holes 230b1 to 230b6, and the six third heat transfer gas supply holes 230c1 to 230c6 are arranged in a so-called staggered shape.

[0106] Here, Figure 9 the comparative example shown is used to illustrate the effects of the present embodiment. In addition, in Figure 9 order to facilitate the description, the illustration of the substrate contact portion 210 is also omitted. In Figure 9 the example shown, compared with Figure 8Similarly, three annular grooves 220, i.e., a first annular groove 220a, a second annular groove 220b, and a third annular groove 220c, are formed on the substrate support surface 111a. However, the heat transfer gas supply holes 230a, 230b, and 230c are not arranged at equal intervals. For example, the distance L21 between the first heat transfer gas supply hole 230a1 and the second heat transfer gas supply hole 230b1 is different from the distance L22 between the first heat transfer gas supply hole 230a1 and the second heat transfer gas supply hole 230b2, and the distance L21 is less than the distance L22. Additionally, for example, the distance L31 between the second heat transfer gas supply hole 230b1 and the third heat transfer gas supply hole 230c1 is different from the distance L32 between the second heat transfer gas supply hole 230b1 and the third heat transfer gas supply hole 230c2, and the distance L31 is less than the distance L32. Furthermore, the arrangement of the heat transfer gas supply holes 230a, 230b, and 230c like this is sometimes referred to as a non-equidistant arrangement.

[0107] In Figure 9 In the example shown, since the distance L21 between the first heat transfer gas supply hole 230a1 and the second heat transfer gas supply hole 230b1 is small, the heat transfer gas flows more easily between the first heat transfer gas supply hole 230a1 and the second heat transfer gas supply hole 230b1 than between the first heat transfer gas supply hole 230a1 and the second heat transfer gas supply hole 230b2. Therefore, it is difficult to generate a pressure difference between the heat transfer space in the region radially inside the annular groove 220a and the heat transfer space in the region between the annular grooves 220a and 220b. Similarly, since the distance L31 between the second heat transfer gas supply hole 230b1 and the third heat transfer gas supply hole 230c1 is small, the heat transfer gas flows more easily between the second heat transfer gas supply hole 230b1 and the third heat transfer gas supply hole 230c1 than between the second heat transfer gas supply hole 230b1 and the third heat transfer gas supply hole 230c2. Therefore, it is difficult to generate a pressure difference between the heat transfer space in the region between the annular grooves 220a and 220b and the heat transfer space in the region between the annular grooves 220b and 220c. As a result, there are cases where the pressure in the heat transfer space of the substrate support surface 111a cannot be properly controlled.

[0108] Regarding this point, when as in the present embodiment Figure 8When the arrangement of the heat transfer gas supply holes 230a and 230b is an equidistant arrangement as shown, the distance L2 between the heat transfer gas supply holes 230a and 230b can be increased. Therefore, the pressure difference can be increased between the heat transfer space in the region radially inside the annular groove 220a and the heat transfer space in the region between the annular grooves 220a and 220b. Similarly, when the arrangement of the heat transfer gas supply holes 230b and 230c is an equidistant arrangement, the distance L3 between the heat transfer gas supply holes 230b and 230c can be increased. Therefore, the pressure difference can be increased between the heat transfer space in the region between the annular grooves 220a and 220b and the heat transfer space in the region between the annular grooves 220b and 220c. Therefore, the pressure in the heat transfer space of the substrate support surface 111a can be appropriately controlled.

[0109] Next, the results of verifying the effects of the present embodiment will be described. Figure 10 The embodiment shown in (a) of Figure 8 is the case where the arrangement of the heat transfer gas supply holes 230a, 230b, and 230c shown is an equidistant arrangement, Figure 10 and the comparative example shown in (b) of Figure 9 is the case where the arrangement of the heat transfer gas supply holes 230a, 230b, and 230c shown is a non-equidistant arrangement. Moreover, in the embodiment and the comparative example, the pressure P2 of the heat transfer gas supplied from the second heat transfer gas supply hole 230b is greater than the pressure P1 of the heat transfer gas supplied from each of the first heat transfer gas supply hole 230a and the third heat transfer gas supply hole 230c. In addition, in Figure 10 the figure of, the vertical axis represents the pressure in the heat transfer space, and the horizontal axis represents the radial position in a specific direction of the substrate W.

[0110] In this case, as Figure 10 shown in (b) of, in the case of non-equidistant arrangement, the peak of the pressure in the heat transfer space is located at a position shifted toward the third annular groove 220c side from the second annular groove 220b. This pressure distribution in the heat transfer space is different from the pressure of the heat transfer gas supplied from the heat transfer gas supply holes 230a, 230b, and 230c. Therefore, in the case of non-equidistant arrangement, the pressure in the heat transfer space cannot be appropriately controlled.

[0111] Regarding this point, as Figure 10 shown in (a) of, in the case of equidistant arrangement, the peak of the pressure in the heat transfer space is located at the position of the second annular groove 220b. This pressure distribution in the heat transfer space is the same as the pressure of the heat transfer gas supplied from the heat transfer gas supply holes 230a, 230b, and 230c. Therefore, in the case of equidistant arrangement, the pressure in the heat transfer space can be appropriately controlled. As a result, the temperature of the substrate W can be appropriately controlled.

[0112] In addition, inFigure 7 and Figure 8 In the example shown in Figure 8 , the heat transfer gas supply holes 230 are arranged at equal intervals, but the arrangement of the heat transfer gas supply holes 230 is not limited thereto. For example, as long as the minimum distance between the heat transfer gas supply holes 230 of the radially adjacent annular grooves 220 is equal to or greater than a predetermined threshold value, the effects of the present embodiment described above can be obtained, and the pressure in the heat transfer space can be appropriately controlled. This threshold value can be determined according to the specifications required for the substrate W, as long as the pressure difference between regions is such that the temperature of the substrate W can be appropriately controlled.

[0113] In addition, in Figure 7 and Figure 8 In the example shown in Figure 8 , the heat transfer gas supply holes 230 are arranged in a staggered pattern, but the arrangement of the heat transfer gas supply holes 230 is not limited thereto. For example, when the number of the first heat transfer gas supply holes 230a formed in the first annular groove 220a is different from the number of the second heat transfer gas supply holes 230b formed in the second annular groove 220b, the arrangement of the heat transfer gas supply holes 230a and 230b may not be in a staggered pattern. As described above, as long as the heat transfer gas supply holes 230a and 230b are arranged at equal intervals, or the minimum distance between the heat transfer gas supply holes 230a and 230b is equal to or greater than a predetermined threshold value.

[0114] In addition, in Figure 7 and Figure 8 In the example shown in Figure 8 , two and three annular grooves 220 are respectively formed in the substrate support surface 111a, but the number of the annular grooves 220 is not limited thereto. For example, four or more annular grooves 220 may be provided in the substrate support surface 111a.

[0115] In addition, in Figure 7 and Figure 8 In the example shown in Figure 8 , the intermediate groove 240 is not formed between the annular grooves 220, but it may be formed with the intermediate groove 240 as shown in the first embodiment. In this case, the pressure in the heat transfer space can be more appropriately controlled.

[0116] <Third Embodiment>

[0117] Next, the structure of the electrostatic chuck 114 of the third embodiment will be described. In the third embodiment, a porous member is provided inside the annular groove 220.

[0118] As Figure 11 and Figure 12As shown, inside each of the three annular grooves 220, namely the first annular groove 220a, the second annular groove 220b, and the third annular groove 220c, which are provided on the substrate support surface 111a, a first porous member 300a, a second porous member 300b, and a third porous member 300c are provided. The porous members 300a, 300b, and 300c each extend in the circumferential direction and are arranged in an annular shape. In addition, the annular grooves 220a, 220b, and 220c are respectively the same as Figure 8 the annular grooves 220a, 220b, and 220c shown. In addition, in the following description, the porous members 300a, 300b, and 300c may sometimes be collectively referred to as the porous member 300.

[0119] The upper surfaces of the porous members 300a, 300b, and 300c are each lower than the upper surface of the substrate contact portion 210. That is, when the substrate W is supported by the electrostatic chuck 114, the porous members 300a, 300b, and 300c do not contact the substrate W.

[0120] As Figure 12 shown, a first annular lower groove 310a and a second annular lower groove 310b are formed below the first porous member 300a and the second porous member 300b, respectively. Although not shown, a third annular lower groove 310c is also formed below the third porous member 300c. The annular lower grooves 310a, 310b, and 310c each have the same shape as the annular grooves 220a, 220b, and 220c and are formed in an annular shape. In addition, in each of the annular lower grooves 310a, 310b, and 310c, heat transfer gas supply holes 230a, 230b, and 230c as Figure 8 shown are formed.

[0121] According to the present embodiment, since the first porous member 300a is arranged to extend in the circumferential direction, the pressure of the heat transfer gas flowing in the first annular lower groove 310a below the first porous member 300a becomes uniform in the circumferential direction. Similarly, the pressure of the heat transfer gas flowing in the annular lower grooves 310b and 310c below the porous members 300b and 300c also becomes uniform in the circumferential direction.

[0122] In this case, for example, as Figure 12As shown, between the heat transfer space between the porous members 300a and 300b and the heat transfer space radially inside the porous member 300a, the gas conductance in the heat transfer space becomes low, and a pressure difference is generated. Thus, when the pressure P2 of the heat transfer gas from the second heat transfer gas supply hole 230b is higher than the pressure P1 of the heat transfer gas from the first heat transfer gas supply hole 230a, the pressure in the heat transfer space between the porous members 300a and 300b changes from P2 to P1 from the radially outer side to the inner side. Therefore, according to the present embodiment, even without the annular grooves 220a, 220b, 220c, by providing the porous members 300a, 300b, 300c, a pressure distribution similar to the pressure distribution of the heat transfer space obtained by the annular grooves 220a, 220b, 220c can be obtained.

[0123] In addition, by providing the porous members 300a, 300b, 300c in the annular grooves 220a, 220b, 220c respectively, a secondary effect of suppressing abnormal discharge can also be obtained.

[0124] Here, it can be seen that when the porosity of the porous member 300 is 45% to 75%, the above-described effect, that is, the effect that the pressure of the heat transfer gas becomes uniform in the circumferential direction, can be obtained. In addition, for example, there is a case where the electrostatic chuck 114 is dry-cleaned using plasma in a state where the substrate W is not supported on the electrostatic chuck 114. In this case, since the porous member 300 is exposed to the plasma, the porous member 300 preferably uses a material having plasma resistance. Therefore, in view of the above situation, the porous member 300 can use, for example, Figure 10 the porous materials A to D shown. In addition, Figure 13 The porous materials A to D shown are an example, and a porous body of a resin such as polytetrafluoroethylene (PTFE) can also be used.

[0125] In addition, in the present embodiment, the porosity of the porous material used for the porous members 300a, 300b, 300c can be changed. For example, the porosity of the second porous member 300b can be made lower than the porosity of the first porous member 300a. The circumferential length of the second porous member 300b is longer than the circumferential length of the first porous member 300a. Therefore, by reducing the porosity of the second porous member 300b, the amount of the heat transfer gas leaking from the second porous member 300b can be suppressed, and the pressure in the second annular lower groove 310b is likely to become uniform in the circumferential direction. Similarly, for example, the porosity of the third porous member 300c can also be made lower than the porosity of the second porous member 300b.

[0126] In addition, in Figure 11In the example shown, the porous components 300a, 300b, and 300c are provided in all of the three annular grooves 220a, 220b, and 220c. However, it is sufficient to provide the porous component 300 in at least any one of the annular grooves 220. As long as at least one porous component 300 is provided, the above-described effects can be obtained.

[0127] In addition, in Figure 11 the example shown, three annular grooves 220 are formed in the substrate support surface 111a. However, the number of the annular grooves 220 is not limited thereto. For example, two or four or more annular grooves 220 may be formed in the substrate support surface 111a.

[0128] In addition, in Figure 11 the example shown, the intermediate groove 240 is not formed between the annular grooves 220. However, the intermediate groove 240 may be formed as shown in the first embodiment. In this case, the pressure in the heat transfer space can be more appropriately controlled.

[0129] In addition, in Figure 11 the example shown, as shown in the second embodiment, the heat transfer gas supply holes 230a, 230b, and 230c are arranged at equal intervals (staggered arrangement). However, the arrangement of the heat transfer gas supply holes 230a, 230b, and 230c is not limited thereto. Since the pressure of the heat transfer gas can be made uniform in the circumferential direction by the porous components 300a, 300b, and 300c, it is sufficient to form at least one of the heat transfer gas supply holes 230a, 230b, and 230c.

[0130] The embodiments disclosed herein should be considered illustrative rather than restrictive in all respects. The above-described embodiments may be omitted, replaced, or changed in various ways without departing from the appended claims and their gist. For example, the constituent elements of the above-described embodiments may be arbitrarily combined. From such an arbitrary combination, of course, the functions and effects of the respective constituent elements involved in the combination can be obtained, and other functions and other effects obvious to those skilled in the art according to the description of this specification can also be obtained.

[0131] In addition, the effects described in this specification are merely illustrative or exemplary and not restrictive. That is, the technology of the present invention can obtain the above-described effects and other effects obvious to those skilled in the art according to the description of this specification, or the technology of the present invention can obtain other effects obvious to those skilled in the art according to the description of this specification in place of the above-described effects.

[0132] In addition, the following technical solution examples also belong to the technical scope of the present invention.

[0133] (1) A substrate processing apparatus, characterized by comprising:

[0134] A substrate processing chamber;

[0135] A substrate support portion disposed in the substrate processing chamber and having at least one first gas supply path and at least one second gas supply path. The substrate support portion has a base and an electrostatic chuck disposed on the base and having an upper surface. A plurality of protrusions, a first annular groove, a second annular groove surrounding the first annular groove, and an annular intermediate groove disposed between the first annular groove and the second annular groove and shallower than the first annular groove and the second annular groove are formed on the upper surface. The first annular groove communicates with the at least one first gas supply path through at least one first gas supply hole, and the second annular groove communicates with the at least one second gas supply path through at least one second gas supply hole;

[0136] At least one first control valve capable of controlling the flow rate or pressure of the gas supplied through the at least one first gas supply path; and

[0137] At least one second control valve capable of controlling the flow rate or pressure of the gas supplied through the at least one second gas supply path.

[0138] (2) The substrate processing apparatus according to (1) above, characterized in that:

[0139] A plurality of the first gas supply holes are formed in the first annular groove,

[0140] A plurality of the second gas supply holes are formed in the second annular groove,

[0141] The first gas supply holes are formed at positions equidistant from two of the second gas supply holes arranged adjacent to each other in the circumferential direction.

[0142] (3) The substrate processing apparatus according to (1) or (2) above, characterized in that: the width of the intermediate groove is greater than or equal to the widths of the first annular groove and the second annular groove.

[0143] (4) The substrate processing apparatus according to any one of (1) to (3) above, characterized in that: the plurality of protrusions are provided in the intermediate groove.

[0144] (5) The substrate processing apparatus according to any one of (1) to (4) above, characterized in that: the upper surface has an annular outer peripheral protrusion surrounding the first annular groove and the second annular groove.

[0145] (6) The substrate processing apparatus according to any one of (1) to (5) above, characterized in that: a porous member is provided inside at least one of the first annular groove and the second annular groove.

[0146] (7) The substrate processing apparatus according to (6) above, characterized in that:

[0147] An annular lower groove is disposed below the porous member,

[0148] At least one of the at least one first gas supply hole and the at least one second gas supply hole is formed in the annular lower groove.

[0149] (8) The substrate processing apparatus according to (6) or (7) above, characterized in that:

[0150] The porous member is provided inside both the first annular groove and the second annular groove,

[0151] The porosity of the porous member provided inside the second annular groove is lower than the porosity of the porous member provided inside the first annular groove.

[0152] (9) A substrate processing apparatus, characterized by comprising:

[0153] A substrate processing chamber;

[0154] A substrate support portion disposed in the substrate processing chamber and having at least one gas supply path, the substrate support portion having a base and an electrostatic chuck disposed on the base and having an upper surface, on which a plurality of protrusions, an annular groove, and an annular intermediate groove disposed at least one of the radially inner side and the radially outer side of the annular groove and shallower than the annular groove are formed, and the annular groove communicates with the at least one gas supply path through at least one gas supply hole; and

[0155] At least one control valve capable of controlling the flow rate or pressure of the gas supplied through the at least one gas supply path.

[0156] (10) A substrate processing apparatus, characterized by comprising:

[0157] A substrate processing chamber;

[0158] A substrate support disposed in the substrate processing chamber and having at least one first gas supply path and at least one second gas supply path, the substrate support having a base and an electrostatic chuck disposed on the base and having an upper surface, on which a plurality of protrusions, a first annular groove, and a second annular groove surrounding the first annular groove are formed, the first annular groove communicating with the at least one first gas supply path through a plurality of first gas supply holes, and the second annular groove communicating with the at least one second gas supply path through a plurality of second gas supply holes;

[0159] At least one first control valve capable of controlling the flow rate or pressure of the gas supplied through the at least one first gas supply path; and

[0160] At least one second control valve capable of controlling the flow rate or pressure of the gas supplied through the at least one second gas supply path,

[0161] The first gas supply holes are provided at positions equidistant from two of the second gas supply holes arranged adjacent to each other in the circumferential direction.

[0162] (11) A substrate processing apparatus, comprising:

[0163] A substrate processing chamber;

[0164] A substrate support disposed in the substrate processing chamber and having at least one first gas supply path and at least one second gas supply path, the substrate support having a base and an electrostatic chuck disposed on the base and having an upper surface, on which a plurality of protrusions, a first annular groove, and a second annular groove surrounding the first annular groove are formed, the first annular groove communicating with the at least one first gas supply path through a plurality of first gas supply holes, and the second annular groove communicating with the at least one second gas supply path through a plurality of second gas supply holes;

[0165] At least one first control valve capable of controlling the flow rate or pressure of the gas supplied through the at least one first gas supply path; and

[0166] At least one second control valve capable of controlling the flow rate or pressure of the gas supplied through the at least one second gas supply path,

[0167] The minimum distance between the first gas supply holes and the second gas supply holes is equal to or greater than a predetermined threshold value.

[0168] (12) A substrate processing apparatus, comprising:

[0169] A substrate processing chamber;

[0170] A substrate support disposed in the substrate processing chamber, having at least one first gas supply path and at least one second gas supply path, the substrate support having a base and an electrostatic chuck disposed on the base and having an upper surface, the upper surface having a plurality of protrusions, a first annular groove, a second annular groove surrounding the first annular groove, a first porous member disposed inside the first annular groove, and a second porous member disposed inside the second annular groove, the first annular groove communicating with the at least one first gas supply path via at least one first gas supply hole, and the second annular groove communicating with the at least one second gas supply path via at least one second gas supply hole;

[0171] At least one first control valve capable of controlling the flow rate or pressure of the gas supplied via the at least one first gas supply path; and

[0172] At least one second control valve capable of controlling the flow rate or pressure of the gas supplied via the at least one second gas supply path.

[0173] (13) An electrostatic chuck, characterized in that:

[0174] It includes a chuck main body having an upper surface, at least one first gas supply path and at least one second gas supply path,

[0175] A plurality of protrusions, a first annular groove, a second annular groove surrounding the first annular groove, and an annular intermediate groove disposed between the first annular groove and the second annular groove and shallower than the first annular groove and the second annular groove are formed on the upper surface,

[0176] The first annular groove communicates with the at least one first gas supply path via at least one first gas supply hole,

[0177] The second annular groove communicates with the at least one second gas supply path via at least one second gas supply hole.

[0178] (14) The electrostatic chuck according to the above (13), characterized in that:

[0179] A plurality of the first gas supply holes are formed in the first annular groove,

[0180] A plurality of the second gas supply holes are formed in the second annular groove,

[0181] The first gas supply holes are formed at positions equidistant from two of the second gas supply holes disposed adjacent to each other in the circumferential direction.

[0182] (15) The electrostatic chuck according to (13) or (14) above, characterized in that: the width of the middle groove is greater than or equal to the width of the first annular groove and the width of the second annular groove.

[0183] (16) The electrostatic chuck according to any one of (13) to (15) above, characterized in that: a plurality of protrusions are provided in the middle groove.

[0184] (17) The electrostatic chuck according to any one of (13) to (16) above, characterized in that: the upper surface has an annular outer peripheral protrusion surrounding the first annular groove and the second annular groove.

[0185] (18) The electrostatic chuck according to any one of (13) to (17) above, characterized in that: a porous member is provided inside at least one of the first annular groove and the second annular groove.

[0186] (19) The electrostatic chuck according to (18) above, characterized in that:

[0187] An annular lower groove is disposed below the porous member,

[0188] At least one of the at least one first gas supply hole and the at least one second gas supply hole is formed in the annular lower groove.

[0189] (20) The electrostatic chuck according to (18) or (19) above, characterized in that:

[0190] The porous member is provided inside both the first annular groove and the second annular groove,

[0191] The porosity of the porous member provided inside the second annular groove is lower than the porosity of the porous member provided inside the first annular groove.

[0192] (21) An electrostatic chuck, characterized in that:

[0193] It includes a chuck body portion having an upper surface and at least one gas supply path,

[0194] A plurality of protrusions, annular grooves, and an annular middle groove disposed at least one of the radially inner side and the radially outer side of the annular groove and shallower than the annular groove are formed on the upper surface,

[0195] The annular groove communicates with the at least one gas supply path via at least one gas supply hole.

[0196] (22) An electrostatic chuck, characterized in that:

[0197] Comprising a chuck body portion having an upper surface, at least one first gas supply path, and at least one second gas supply path,

[0198] On the upper surface, a plurality of protrusions, a first annular groove, and a second annular groove surrounding the first annular groove are formed,

[0199] The first annular groove communicates with the at least one first gas supply path via a plurality of first gas supply holes,

[0200] The second annular groove communicates with the at least one second gas supply path via a plurality of second gas supply holes,

[0201] The first gas supply holes are provided at positions equidistant from two of the second gas supply holes arranged adjacent to each other in the circumferential direction.

[0202] (23) A substrate processing apparatus, characterized in that:

[0203] Comprising a chuck body portion having an upper surface, at least one first gas supply path, and at least one second gas supply path,

[0204] On the upper surface, a plurality of protrusions, a first annular groove, and a second annular groove surrounding the first annular groove are formed,

[0205] The first annular groove communicates with the at least one first gas supply path via a plurality of first gas supply holes,

[0206] The second annular groove communicates with the at least one second gas supply path via a plurality of second gas supply holes,

[0207] The minimum distance between the first gas supply holes and the second gas supply holes is equal to or greater than a predetermined threshold value.

[0208] (24) An electrostatic chuck, characterized in that:

[0209] Comprising a chuck body portion having an upper surface, at least one first gas supply path, and at least one second gas supply path,

[0210] The upper surface has a plurality of protrusions, a first annular groove, a second annular groove surrounding the first annular groove, a first porous member provided inside the first annular groove, and a second porous member provided inside the second annular groove,

[0211] The first annular groove communicates with the at least one first gas supply path via at least one first gas supply hole,

[0212] The second annular groove communicates with the at least one second gas supply path via at least one second gas supply hole.

[0213] Description of Reference Numerals

[0214] 1 Plasma processing apparatus, 10 Plasma processing chamber, 11 Substrate support portion, 111a Substrate support surface, 113 Base, 114 Electrostatic chuck, 210 Substrate contact portion, 220a First annular groove, 220b Second annular groove, 230a First heat transfer gas supply hole, 230b Second heat transfer gas supply hole, 231a First heat transfer gas supply path, 231b Second heat transfer gas supply path, 233a First control valve, 233b Second control valve, 240 Intermediate groove.

Claims

1. A substrate processing apparatus, characterized in that, Comprising: A substrate processing chamber; A substrate support disposed in the substrate processing chamber, having at least one first gas supply path and at least one second gas supply path, the substrate support having a base and an electrostatic chuck disposed on the base and having an upper surface, on which a plurality of protrusions, a first annular groove, a second annular groove surrounding the first annular groove, and an annular intermediate groove disposed between the first annular groove and the second annular groove and shallower than the first annular groove and the second annular groove are formed, the first annular groove communicating with the at least one first gas supply path via at least one first gas supply hole, and the second annular groove communicating with the at least one second gas supply path via at least one second gas supply hole; At least one first control valve capable of controlling the flow rate or pressure of the gas supplied via the at least one first gas supply path; and At least one second control valve capable of controlling the flow rate or pressure of the gas supplied via the at least one second gas supply path.

2. The substrate processing apparatus according to claim 1, wherein: A plurality of the first gas supply holes are formed in the first annular groove, A plurality of the second gas supply holes are formed in the second annular groove, The first gas supply holes are formed at positions equidistant from two of the second gas supply holes arranged adjacent to each other in the circumferential direction.

3. The substrate processing apparatus according to claim 1, wherein: The width of the intermediate groove is greater than or equal to the widths of the first annular groove and the second annular groove.

4. The substrate processing apparatus according to claim 1, wherein: The plurality of protrusions are provided in the intermediate groove.

5. The substrate processing apparatus according to claim 1, wherein: The upper surface has an annular outer peripheral protrusion surrounding the first annular groove and the second annular groove.

6. The substrate processing apparatus according to claim 1, wherein: A porous member is provided inside at least one of the first annular groove and the second annular groove.

7. The substrate processing apparatus according to claim 6, wherein: An annular lower groove is disposed below the porous member, At least one of the at least one first gas supply hole and the at least one second gas supply hole is formed in the annular lower groove.

8. The substrate processing apparatus according to claim 6, wherein: The porous members are provided inside both the first annular groove and the second annular groove, The porosity of the porous member provided inside the second annular groove is lower than the porosity of the porous member provided inside the first annular groove.

9. An electrostatic chuck, characterized in that: It includes a chuck body portion having an upper surface, at least one first gas supply path and at least one second gas supply path, On the upper surface, a plurality of protrusions, a first annular groove, a second annular groove surrounding the first annular groove, and an annular intermediate groove disposed between the first annular groove and the second annular groove and shallower than the first annular groove and the second annular groove are formed. The first annular groove communicates with the at least one first gas supply path via at least one first gas supply hole. The second annular groove communicates with the at least one second gas supply path via at least one second gas supply hole.

10. The electrostatic chuck according to claim 9, wherein: A plurality of the first gas supply holes are formed in the first annular groove. A plurality of the second gas supply holes are formed in the second annular groove. The first gas supply holes are formed at positions equidistant from two of the second gas supply holes disposed adjacent to each other in the circumferential direction.

11. The electrostatic chuck according to claim 9, wherein: The width of the intermediate groove is greater than or equal to the widths of the first annular groove and the second annular groove.

12. The electrostatic chuck according to claim 9, wherein: The plurality of protrusions are provided in the intermediate groove.

13. The electrostatic chuck according to claim 9, wherein: The upper surface has an annular outer peripheral protrusion surrounding the first annular groove and the second annular groove.

14. The electrostatic chuck according to claim 9, wherein: A porous member is provided inside at least one of the first annular groove and the second annular groove.

15. The electrostatic chuck according to claim 14, wherein: An annular lower groove is disposed below the porous member. At least one of the at least one first gas supply hole and the at least one second gas supply hole is formed in the annular lower groove.

16. The electrostatic chuck according to claim 14, wherein: The porous member is provided inside both the first annular groove and the second annular groove. The porosity of the porous member provided inside the second annular groove is lower than the porosity of the porous member provided inside the first annular groove.

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