JP7623083B2 - Substrate support and plasma processing apparatus - Google Patents

Description

The present disclosure relates to a substrate support and a plasma processing apparatus.

For example, Patent Document 1 proposes a power supply mechanism that supplies power to a heater electrode arranged on a substrate support part on which a substrate is placed. The inner wall of a through hole in the base of the substrate support part is covered by a sleeve, and a power supply mechanism is provided inside the sleeve. The power supply mechanism has a contact and wiring that are connected to the heater electrode. A second portion of the wiring supports the first portion such that the first portion of the wiring is bent between the contact and the second portion.

JP 2016-27601 A

If the power supply section does not have good heat dissipation properties, it is prone to temperature singularities.

This disclosure provides technology that can improve heat dissipation in the power supply section of the substrate support.

According to one aspect of the present disclosure, a substrate support is provided that includes an electrostatic chuck for placing a substrate thereon, a base supporting the electrostatic chuck, a first power supply terminal electrically connected to an electrode in the electrostatic chuck, a second power supply terminal disposed within a through hole in the base at a distance from the first power supply terminal, a flexible power supply line electrically connecting the first power supply terminal and the second power supply terminal, and a heat transfer member provided between the second power supply terminal and the base.

According to one aspect, it is possible to improve the heat dissipation in the power supply section of the substrate support part.

FIG. 1 illustrates an example of a plasma processing system according to an embodiment. 1 is a schematic cross-sectional view showing an example of a plasma processing apparatus according to an embodiment; 3 is a schematic cross-sectional view showing an example of a main part of a substrate support part in the plasma processing apparatus of FIG. 2 . FIG. 4 is an enlarged cross-sectional view of a power supply portion and its vicinity of the substrate support portion according to the embodiment. 6A and 6B are diagrams for explaining the effect of a power supply part of a substrate support part according to an embodiment. 13A and 13B are diagrams illustrating modified examples of a power supply unit of a substrate support unit according to an embodiment.

Below, a description will be given of a mode for carrying out the present disclosure with reference to the drawings. In each drawing, the same components are given the same reference numerals, and duplicate descriptions may be omitted.

[Plasma Processing System]
First, a plasma processing system according to an embodiment will be described with reference to FIG. 1. FIG. 1 is a diagram showing an example of a plasma processing system according to an embodiment. In the embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support unit 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 unit 11 is disposed in the plasma processing space, and has a substrate support surface for supporting a substrate.

The plasma generating unit 12 is configured to 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), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), or surface wave plasma (SWP). Also, various types of plasma generating units may be used, including AC (Alternating Current) plasma generating units and DC (Direct Current) plasma generating units. In one embodiment, the AC signal (AC power) used in the AC plasma generating unit has a frequency in the range of 100 kHz to 10 GHz. Thus, AC signals include RF (Radio Frequency) signals and microwave signals. In one embodiment, the RF signal has a frequency in the range of 200 kHz to 150 MHz.

The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform the various steps described in this disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform the various steps described herein. In one embodiment, a part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 may include, for example, a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a memory unit 2a2, and a communication interface 2a3. The processing unit 2a1 may be configured to perform various control operations based on a program stored in the memory unit 2a2. The memory unit 2a2 may include a RAM (Random Access Memory), a ROM (Read Only Memory), a HDD (Hard Disk Drive), an SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing device 1 via a communication line such as a LAN (Local Area Network).

[Plasma Processing System]
Next, a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1 will be described with reference to Fig. 2. Fig. 2 is a schematic cross-sectional view showing an example of the plasma processing apparatus 1 according to an embodiment.

The 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 processing gas into the plasma processing chamber 10. The gas inlet includes a shower head 13. The substrate support 11 is disposed in the plasma processing chamber 10. The shower head 13 is disposed above the substrate support 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, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The sidewall 10a is grounded. The shower head 13 and the substrate support 11 are electrically insulated from the plasma processing chamber 10 housing.

The substrate support 11 includes a base 122 and an electrostatic chuck 111. The substrate support 11 further includes a ring assembly 112. The electrostatic chuck 111 has a central region (substrate support surface) 111a for placing a substrate W, such as a wafer, and an annular region (ring support surface) 111b for placing the ring assembly 112. The annular region 111b of the electrostatic chuck 111 surrounds the central region 111a of the electrostatic chuck 111 in a planar view. The substrate W is disposed on the central region 111a of the electrostatic chuck 111, and the ring assembly 112 is disposed on the annular region 111b of the electrostatic chuck 111 so as to surround the substrate W on the central region 111a of the electrostatic chuck 111. In one embodiment, the base 122 includes a conductive member. The conductive member of the base 122 functions as a lower electrode. The base 122 supports the electrostatic chuck 111, and the electrostatic chuck 111 is disposed on the base 122. The upper surface of the electrostatic chuck 111 has a substrate support surface 111a. The ring assembly 112 includes one or more annular members. At least one of the one or more annular members is an edge ring. Although not shown, the substrate support 11 may include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 111, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow path 123, or a combination thereof. A heat exchange medium flows through the flow path 123. The heat exchange medium is a liquid or a gas. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface 111a. In one embodiment, the flow path 123 is formed in the base 122, but is not limited thereto.

The shower head 13 is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The shower head 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The processing 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 shower head 13 also includes a conductive member. The conductive member of the shower head 13 functions as an upper electrode. In addition to the shower head 13, the gas introduction unit may include one or more side gas injectors (SGIs) attached to one or more openings formed in the side wall 10a.

The gas supply 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply 20 is configured to supply at least one process gas from a respective gas source 21 through a respective flow controller 22 to the showerhead 13. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply 20 may include at least one flow modulation device that modulates or pulses the flow rate of the at least one process gas.

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), such as a source RF signal and a bias RF signal, to the conductive member of the substrate support 11 and/or the conductive member of the showerhead 13. This causes a plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Thus, the RF power supply 31 can function as at least a part of the plasma generating unit 12. In addition, by supplying a bias RF signal to the conductive member of the substrate support 11, a bias potential is generated on the substrate W, and ion components in the formed plasma can be attracted to the substrate W.

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 the conductive member of the substrate support 11 and/or the conductive member of the shower head 13 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 13 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 the conductive member of the substrate support 11 and/or the conductive member of the shower head 13. The second RF generating unit 31b is coupled to the conductive member of the substrate support 11 via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). In one embodiment, the bias RF signal has a lower frequency than the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 400 kHz to 13.56 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated bias RF signal or signals are provided to the conductive members of the substrate support 11. Also, in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

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 a conductive member of the substrate support 11 and configured to generate a first DC signal. The generated first DC signal is applied to the conductive member of the substrate support 11. In one embodiment, the first DC signal may be applied to another electrode, such as an electrode in an electrostatic chuck. In one embodiment, the second DC generator 32b is connected to a conductive member of the showerhead 13 and configured to generate a second DC signal. The generated second DC signal is applied to the conductive member of the showerhead 13. In various embodiments, the first and second DC signals may be pulsed. The first and second DC generating units 32a and 32b may be provided in addition to the RF power source 31, or the first DC generating unit 32a may be provided in place of the second RF generating unit 31b.

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 adjusted by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[Substrate support part]
Next, the configuration of the substrate support part 11 will be described with reference to Fig. 3. Fig. 3 is a schematic cross-sectional view showing a main part of the substrate support part 11 in the plasma processing apparatus 1 of Fig. 2. The substrate support part 11 has a base 122, an electrostatic chuck 111 on the base 122, and a ring assembly 112 on a ring support surface 111b on the outer periphery of the electrostatic chuck 111. The base 122 is substantially cylindrical and is formed of a conductive member such as aluminum.

A flow path 123 formed inside the base 122 is located below the substrate W and the ring assembly 112, is connected to a chiller unit (not shown), and circulates a heat exchange medium controlled to a desired temperature by the chiller unit. The base 122 functions to absorb heat from the substrate W and the ring assembly 112 by the heat exchange medium circulating through the flow path 123. The electrostatic chuck 111 is, for example, substantially cylindrical, and is formed of an insulating member such as ceramics. For example, the electrostatic chuck 111 is a sintered body of alumina (Al ₂ O ₃ ) ceramics. Note that the electrostatic chuck 111 is not limited to an alumina ceramic sintered body. For example, the electrostatic chuck 111 may be a sintered body containing at least one material selected from the group consisting of alumina, yttria (Y ₂ O ₃ ), silicon carbide (SiC), aluminum nitride (AlN), and silicon nitride (Si ₃ N ₄ ).

The substrate support surface 111a of the electrostatic chuck 111 is circular and contacts the back surface of the substrate W to support the disk-shaped substrate W. The ring support surface 111b of the electrostatic chuck 111 is annular and contacts the back surface of the ring assembly 112 to support the annular ring assembly 112.

The electrostatic chuck 111 is formed integrally with a central portion 111c having a substrate support surface 111a as its upper surface and a peripheral portion 111d having a ring support surface 111b as its upper surface. The height of the central portion 111c of the electrostatic chuck 111 is greater than the height of the peripheral portion 111d.

An electrode 230 is embedded in the center 111c of the electrostatic chuck 111, and an electrode 231 is embedded in the outer periphery 111d. The electrodes 230 and 231 may be RF electrodes for applying an RF signal (RF power) from the RF power source 31, or may be DC electrodes for applying a DC signal (DC power) from the DC power source 32. The electrodes 230 and 231 may be chucking electrodes for electrostatically chucking the substrate W and the ring assembly 112, or may be heater electrodes for heating the substrate W and the ring assembly 112.

The ring assembly 112 is disposed around the substrate W. The ring assembly 112 is substantially annular and is made of, for example, Si (silicon) or SiC. A convex portion that protrudes radially inward is formed on the inner surface of the ring assembly 112. In other words, the inner diameter of the lower side of the inner surface of the ring assembly 112 is smaller than the inner diameter of the upper side.

Power supply units 200a, 200b, and 200c are electrically connected to an electrode 230 in the electrostatic chuck 111 below the substrate W and an electrode 231 in the electrostatic chuck 111 below the ring assembly 112. In the following, heater electrodes will be described as an example of the electrodes 230 and 231. The electrodes 230 and 231 are sprayed heater electrodes formed by a thermal spraying method. The electrodes 230 and 231 function as heating elements for heating the substrate W and the ring assembly 112. The electrodes 230 and 231 are, for example, metal films.

When power is supplied to the electrode 230 from the heater power supply 14 shown in FIG. 1, the power is supplied to the electrode 230 via the power supply unit 200b arranged below the electrode 230.

Similarly, when power is supplied to the electrode 231 from the heater power supply 14, power is supplied to the electrode 231 via the power supply units 200a and 200c that are arranged at intervals on the lower part of the electrode 231. The configurations of the power supply units 200a, 200b, and 200c are the same. Hereinafter, the power supply units 200a, 200b, and 200c are collectively referred to as the power supply unit 200.

The power supply unit 200 provided below the electrode 230 is shown as power supply unit 200b in FIG. 3, but the number of power supply units 200 may be at least one. Similarly, the power supply unit 200 provided below the electrode 231 is shown as power supply units 200a and 200c in FIG. 3, but the number of power supply units 200 may be at least one.

The power supply unit 200 will be described with reference to FIG. 4. FIG. 4 is an enlarged cross-sectional view of the power supply unit 200a of the substrate support unit 11 according to one embodiment, as an example of the power supply unit 200. As shown in FIG. 4, a through hole HL is formed in the base 122 located below the electrode 231 of the outer periphery 111d of the electrostatic chuck 111, penetrating from the back surface 122a to the upper surface 122b of the base 122. The inner wall of the through hole HL is covered by a cylindrical sleeve 204. The sleeve 204 is formed of an insulating material such as alumina. The sleeve 204 has a step portion 204b that protrudes to the outer periphery at the upper part.

A power supply unit 200a electrically connected to the electrode 231 is provided in the through hole HL. The power supply unit 200a has a first power supply terminal 201, a second power supply terminal 202, a power supply line 203, and an adhesive 205. The adhesive 205 is an example of a heat transfer member provided between the second power supply terminal 202 and the base 122.

The first power supply terminal 201 is electrically connected to the electrode 231. The first power supply terminal 201 has a first partial terminal 201a and a second partial terminal 201b. The first partial terminal 201a is embedded in the electrostatic chuck 111, its upper surface is in contact with the electrode 231, its lower surface faces the lower surface 111e of the electrostatic chuck 111, and is joined to the second partial terminal 201b by brazing.

The second partial terminal 201b protrudes into the through hole HL beyond the lower surface 111e of the electrostatic chuck 111. The second partial terminal 201b is electrically connected to the second power supply terminal 202 via a power supply line 203 in the through hole HL. The second power supply terminal 202 is cylindrical and has a recess 202a inside.

The first partial terminal 201a and the second partial terminal 201b are made of a conductive material. Examples of conductive materials include conductive ceramics and copper, and examples of conductive ceramics include aluminum nitride.

The second power supply terminal 202 is disposed in the through hole HL at a distance from the first power supply terminal 201. The adhesive 205 is provided between the second power supply terminal 202 and the base 122. In this embodiment, the sleeve 204 in the base 122 and the second power supply terminal 202 are in contact with each other via the adhesive 205. In other words, the adhesive 205 is not filled in the entire through hole HL, but is applied to the outer periphery of the second partial terminal 201b provided at the bottom of the through hole HL and between the base 122 (sleeve 204). The adhesive is not filled in the space U in which the power supply line 203 is disposed above the through hole HL. As a result, in order to dissipate heat from the power supply unit 200a, the contact area between the second power supply terminal 202 and the base 122 via the adhesive 205 can be maintained, and heat can be released from the second power supply terminal 202 to the base 122 side, thereby improving heat dissipation.

The power supply line 203 electrically connects the first power supply terminal 201 and the second power supply terminal 202 and has flexibility. This makes it possible to reduce stress generated in the first power supply terminal 201 and the second power supply terminal 202.

[effect]
The above effects will be described with reference to Fig. 5. Fig. 5 is a diagram for explaining the effects of power supply unit 200 of substrate support unit 11 according to one embodiment. Fig. 5(a) shows the state of power supply unit 200b electrically connected to electrode 230 arranged below substrate W when heat is input. Fig. 5(b) shows the state of power supply unit 200b when heated. Fig. 5(c) shows the state of power supply unit 200b when cooled. Power supply unit 200b is an example of power supply unit 200, and the same effects can be obtained for power supply unit 200a and power supply unit 200c having the same configuration.

First, the heat dissipation effect of the power supply unit 200 will be described with reference to FIG. 5(a), and then the stress suppression effect on the power supply unit 200 due to thermal stress will be described with reference to FIGS. 5(b) and (c).

As shown in FIG. 5(a), the heat generated by the electrode 230 and the heat input from the plasma pass through the substrate W and the electrostatic chuck 111 and are received by the first power supply terminal 201 of the power supply unit 200b. The heat received by the first power supply terminal 201 can be dissipated to the base 122 from the adhesive 205 on the outer periphery of the second power supply terminal 202 via the power supply line 203 and the second power supply terminal 202.

The adhesive 205 may be, for example, a silicone-based, epoxy-based, or acrylic-based adhesive. The adhesive 205 has a thermal resistivity of, for example, 14 K/W to 50 K/W. As shown in FIG. 4, the inner diameter φ1 of the adhesive 205, i.e., the outer diameter of the second power supply terminal 202, is 6 mm, and the outer diameter φ2 of the adhesive 205, i.e., the inner diameter of the sleeve 204, is 9 mm.

In this manner, in this embodiment, the adhesive 205 is filled between the second power supply terminal 202 and the base 122 over the entire outer periphery to ensure a sufficient contact area between the second power supply terminal 202 and the base 122, and a material with low thermal resistance is used for the adhesive 205, thereby improving heat dissipation. This improvement in the heat dissipation of the power supply unit 200 makes it possible to prevent the power supply unit 200a from becoming a temperature singularity of the substrate W. This makes it possible to prevent a decrease in the temperature uniformity of the substrate W.

The lower the thermal resistivity of the adhesive 205, the better the thermal conduction from the second power supply terminal 202 to the base 122, which is preferable. Therefore, in order to reduce the thermal resistance between the second power supply terminal 202 and the base 122, the adhesive 205 is made thinner or the length over which the adhesive 205 is applied is increased. This can reduce the thermal resistance. For example, by increasing the cylindrical length of the second power supply terminal 202 and increasing the surface area, the length over which the adhesive 205 is applied can be increased, and the thermal resistance can be reduced.

In the power supply unit 200 according to this embodiment, in addition to the heat dissipation effect described above, the flexibility of the power supply line 203 shown in Figs. 5(b) and (c) can be used to suppress the occurrence of shear, compression, and tension. This effect will be described next.

The power supply line 203 electrically connects the first power supply terminal 201 and the second power supply terminal 202, and is flexible. The power supply line 203 is a twisted wire made by twisting together multiple conductors, and is made of a flexible conductive material that can be bent, making it deformable. The first power supply terminal 201 is connected to one end of the power supply line 203 on the surface opposite to the surface connected to the electrode 231. The second power supply terminal 202 is connected to the other end of the power supply line 203 on the top surface.

The space U in which the power supply line 203 exists is an atmospheric space. In other words, the space U in the through hole HL in which the power supply line 203 exists between the first power supply terminal 201 and the second power supply terminal 202 is not filled with adhesive.

The power supply line 203 can therefore deform in response to temperature changes in the space U between the first power supply terminal 201 and the second power supply terminal 202. Power supplied from the heater power supply 14 is supplied to the electrode 230 via the power supply line, the second power supply terminal 202, the power supply line 203, and the first power supply terminal 201. The electrode 230 generates heat due to the supplied power, and the power supply section 200b and its surroundings are heated.

The power supply unit 200b and its surroundings are heated by heat input from the plasma. The surroundings around the power supply unit 200b are made of materials with different linear expansion coefficients: the electrostatic chuck 111 is made of ceramics, and the base 122 is made of aluminum.

For this reason, during heating as shown in FIG. 5(b), since the electrostatic chuck 111 has a relatively smaller thermal expansion than the base 122, a shear force is applied to the first partial terminal 201a of the first power supply terminal 201 in the direction indicated by the inward arrow. On the other hand, since the base 122 has a relatively larger thermal expansion than the electrostatic chuck 111, a shear force is applied to the second partial terminal 201b of the first power supply terminal 201 in the direction indicated by the opposite outward arrow.

As a result, a force acts in the shear direction at the interface A between the first partial terminal 201a and the second partial terminal 201b, generating stress. When a force acts in the shear direction in this manner, peeling occurs at the interface A where the first partial terminal 201a and the second partial terminal 201b are brazed, and the electrical connection between the first power supply terminal 201 and the electrode 231 is severed.

During cooling as shown in FIG. 5(c), due to the difference in the linear expansion coefficient between the electrostatic chuck 111 and the base 122, the first partial terminal 201a is subjected to a shearing force in the direction indicated by the outward arrow, and the second partial terminal 201b is subjected to a shearing force in the opposite direction indicated by the inward arrow.

In contrast, the configuration of the power supply unit 200 according to this embodiment allows the flexibility of the power supply line 203 to absorb the difference in displacement of the electrostatic chuck 111 and the base 122 due to thermal expansion. In other words, the flexible power supply line 203 is not subjected to the shear force.

If the space U in which the power supply line 203 exists is filled with adhesive, excessive thermal stress will be generated in the power supply line 203 due to heat input from the plasma, etc., and the thermal stress applied to the first power supply terminal 201 cannot be absorbed, which may result in poor connection or damage to the power supply unit 200. However, in this embodiment, the power supply line 203 is flexible, and the space U is not filled with adhesive. Therefore, the power supply line 203 can freely deform in response to the thermal stress, thereby absorbing the thermal stress. This makes it possible to avoid poor electrical connection or damage to the power supply unit 200.

[Modification]
Modifications of the power supply unit 200 of the substrate support unit according to an embodiment will be described with reference to Fig. 6, taking power supply unit 200a as an example. Fig. 6 is a diagram showing modifications 1 to 3 of the power supply unit 200a of the substrate support unit according to an embodiment. Fig. 6(a) shows modification 1 of the power supply unit 200a, Fig. 6(b) shows modification 2 of the power supply unit 200a, and Fig. 6(c) shows modification 3 of the power supply unit 200a.

The power supply unit 200a in modified example 1 shown in FIG. 6(a) has a ring-shaped partition 206 that separates the adhesive 205 from the area (space U) in which the power supply line 203 is provided. The adhesive 205 and the partition 206 are an example of a heat transfer member provided between the second power supply terminal 202 and the base 122.

The partition 206 functions as a stopper to prevent the adhesive 205 from filling the space U when the adhesive 205 is filled between the second power supply terminal 202 and the sleeve 204 by turning the paper of FIG. 6(a) upside down. At the same time, the partition 206 also serves the purpose of fixing the position of the second power supply terminal 202 at a desired position. That is, first, the partition 206 is abutted against the step portion 204c of the sleeve 204, and the partition 206 is fixed with adhesive. Next, the second power supply terminal 202 is fitted into the ring-shaped partition 206, and the position of the second power supply terminal 202 is fixed. After this, the adhesive 205 is poured between the second power supply terminal 202 and the sleeve 204.

The partition 206 is preferably made of an insulating material that can withstand heat treatment at approximately 150°C to 200°C, such as Poly Ether Ether Ketone (PEEK). The partition 206 may be made of insulating ceramics or resin.

In the second modification of the power supply unit 200a shown in FIG. 6(b), a cylinder 207 made of a metal or a highly heat-conductive insulating material is inserted between the second power supply terminal 202 and the base 122. The cylinder 207 is an example of a heat transfer member provided between the second power supply terminal 202 and the base 122. When the cylinder 207 is made of a metal, it is preferably a metal with high thermal conductivity such as copper or aluminum. When the cylinder 207 is made of a highly heat-conductive insulating material, it is preferably an insulator with high thermal conductivity such as aluminum nitride.

Adhesives 205a and 205b are provided between the cylinder 207 and the second power supply terminal 202, and between the cylinder 207 and the sleeve 204, respectively. In the second modification, the adhesives 205a and 205b can be made thinner. This can further reduce the thermal resistance caused by the adhesive. In addition, the thermal conductivity can be increased by forming the cylinder 207 from a metal or a highly heat-conductive insulating material. This can improve the heat dissipation from the second power supply terminal 202 to the base 122. Note that in the power supply unit 200 according to the second modification, the partition 206 of the first modification may be provided between the cylinder 207 and the space U above it, or the partition 206 may be omitted.

In the third modification of the power supply unit 200a shown in FIG. 6(c), a cylinder 208 having a refrigerant flow path 208a for cooling the inside of the through hole HL is provided between the second power supply terminal 202 and the base 122. The cylinder 208 is provided between the second power supply terminal 202 and the base 122, and is an example of a heat transfer member having a cooling mechanism for cooling the inside of the through hole in the base.

Cylinder 208 has a configuration in which a space is provided inside cylinder 207 of variant 2, and may be formed from a metal such as aluminum, or a highly heat-conductive insulating material such as aluminum nitride.

A supply line capable of circulating a refrigerant at a desired temperature supplied from a chiller unit 209 is connected to the refrigerant flow path 208a. This allows the heat extraction performance of the power supply unit 200 to be further improved by the refrigerant circulating through the refrigerant flow path 208a of the cylinder 208.

The refrigerant flow path 208a is an example of a cooling mechanism that cools the inside of the through hole HL in the base 122. The refrigerant may be a gas or a liquid. The refrigerant may be circulated from the refrigerant flow path 208a to the inside of the space U. The space U may also be filled with liquid instead of air. The inside of the adhesive 205 may be left as a space, and this space may be used as the refrigerant flow path 208a. Instead of the adhesive 205 below the ring-shaped partition 206, the space below the partition 206 may be used as the refrigerant flow path 208a.

As described above, the power supply unit 200 and plasma processing apparatus 1 of this embodiment can improve the heat dissipation performance of the power supply unit 200. In addition, when thermal stress occurs due to the difference in the linear expansion coefficient between the electrostatic chuck 111 and the base 122, the flexibility of the power supply line 203 absorbs the misalignment of each component. This absorbs the thermal stress applied to the first power supply terminal 201, thereby preventing poor connection or damage to the power supply unit 200.

The substrate support and plasma processing apparatus according to the disclosed embodiments should be considered in all respects as illustrative and not restrictive. The embodiments may be modified and improved in various ways without departing from the spirit and scope of the appended claims. The matters described in the above embodiments may be configured in other ways without any inconsistency, and may be combined without any inconsistency.

The plasma processing apparatus disclosed herein can be applied to any type of apparatus, including Atomic Layer Deposition (ALD) apparatus, Capacitively Coupled Plasma (CCP), Inductively Coupled Plasma (ICP), Radial Line Slot Antenna (RLSA), Electron Cyclotron Resonance Plasma (ECR), and Helicon Wave Plasma (HWP).

REFERENCE SIGNS LIST 1 Plasma processing apparatus 2 Control unit 10 Plasma processing chamber 11 Substrate support unit 13 Shower head 21 Gas source 20 Gas supply unit 30 Power supply 31 RF power supply 31a First RF generator 31b Second RF generator 32a First DC generator 32b Second DC generator 40 Exhaust system 111 Electrostatic chuck 112 Ring assembly 122 Base 200 Power supply unit 201 First power supply terminal 202 Second power supply terminal 203 Power supply line 205 Adhesive 206 Partition unit 207 Cylinder

Claims (12)

an electrostatic chuck on which the substrate is placed;
A base supporting the electrostatic chuck;
a first power supply terminal electrically connected to an electrode in the electrostatic chuck;
a cylindrical second power supply terminal disposed in the through hole of the base and spaced apart from the first power supply terminal , the second power supply terminal having a downward recess with its upper surface as a bottom ;
a flexible power supply line electrically connecting a lower surface of the first power supply terminal and the upper surface of the second power supply terminal;
a cylindrical insulating sleeve disposed only on an inner wall of the through hole and containing the second power supply terminal;
a heat transfer member provided between an outer periphery of the second power supply terminal and an inner periphery of the sleeve ;
A substrate support having a The heat transfer member is an adhesive.
The substrate support of claim 1 . The heat transfer member has a partition portion that separates the adhesive from a region in which the power supply line is provided.
The substrate support of claim 2 . The heat transfer member is a metal or a highly heat conductive insulating member.
The substrate support of claim 1 . the through hole in the base between the first power supply terminal and the second power supply terminal is not filled with adhesive;
A substrate support according to any one of claims 1 to 4 . The heat transfer member has a cooling mechanism that cools the inside of the through hole in the base.
A substrate support according to any one of claims 1 to 5 . an electrostatic chuck on which the substrate is placed;
A base supporting the electrostatic chuck;
a first power supply terminal electrically connected to an electrode in the electrostatic chuck;
a cylindrical second power supply terminal disposed in the through hole of the base and spaced apart from the first power supply terminal , the second power supply terminal having a downward recess with its upper surface as a bottom ;
a flexible power supply line electrically connecting a lower surface of the first power supply terminal and the upper surface of the second power supply terminal;
a cylindrical insulating sleeve disposed only on an inner wall of the through hole and containing the second power supply terminal;
a heat transfer member provided between an outer periphery of the second power supply terminal and an inner periphery of the sleeve ,
A plasma processing apparatus comprising a substrate support. The heat transfer member is an adhesive.
The plasma processing apparatus according to claim 7 . The heat transfer member has a partition portion that separates the adhesive from a region in which the power supply line is provided.
The plasma processing apparatus according to claim 8 . The heat transfer member is a metal or a highly heat conductive insulating member.
The plasma processing apparatus according to claim 7 . the through hole in the base between the first power supply terminal and the second power supply terminal is not filled with adhesive;
The plasma processing apparatus according to any one of claims 7 to 10. The heat transfer member has a cooling mechanism that cools the inside of the through hole in the base.
The plasma processing apparatus according to any one of claims 7 to 11.

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