Substrate support and substrate treatment device

Abstract

Disclosed is a substrate support comprising: a base; an electrostatic chuck; at least one protrusion; and an adhesive. The base includes a first body. The first body has an upper surface. The electrostatic chuck includes a second body. The second body has a lower surface and has a thickness of 0.5-1.0 mm. The electrostatic chuck is disposed on the base. The at least one protrusion protrudes from one of the upper surface of the first body and the lower surface of the second body toward the other of the upper surface of the first body and the lower surface of the second body. The at least one protrusion defines a gap between the upper surface of the first body and the lower surface of the second body. The adhesive bonds the electrostatic chuck to the base. The adhesive is disposed in the gap.

Description

Substrate support and substrate processing apparatus

[0001] SUMMARY Exemplary embodiments of the present disclosure relate to a substrate support and a substrate processing apparatus.

[0002] A plasma processing apparatus is used for plasma processing of a substrate. The plasma processing apparatus includes a chamber and a substrate support. The substrate support is disposed in the chamber. Patent Document 1 listed below discloses a substrate support including a base, an electrostatic chuck, and an adhesive. The adhesive is positioned between the base and the electrostatic chuck and adheres the electrostatic chuck to the base.

[0003] Japanese Patent Application Laid-Open No. 2008-251854

[0004] The present disclosure provides techniques for reducing the temperature difference between the base and the electrostatic chuck.

[0005] In one exemplary embodiment, a substrate support is provided. The substrate support includes a base, an electrostatic chuck, at least one protrusion, and an adhesive. The base includes a first body portion. The first body portion has an upper surface. The electrostatic chuck includes a second body portion. The second body portion has a lower surface and has a thickness of 0.5 mm or more and 1.0 mm or less. The second body portion is configured to hold a substrate disposed thereon. The electrostatic chuck is disposed on the base. The at least one protrusion protrudes from one of the upper surface of the first body portion and the lower surface of the second body portion toward the other of the upper surface of the first body portion and the lower surface of the second body portion. The at least one protrusion defines a gap between the upper surface of the first body portion and the lower surface of the second body portion. The adhesive bonds the electrostatic chuck to the base. The adhesive is disposed in the gap.

[0006] According to one exemplary embodiment, the temperature difference between the pedestal and the electrostatic chuck is reduced.

[0007] Fig. 1 is a diagram for explaining an example of the configuration of a plasma processing system. Fig. 2 is a diagram for explaining an example of the configuration of a capacitively coupled plasma processing apparatus. Fig. 3 is an enlarged cross-sectional view of a substrate support according to one exemplary embodiment. Fig. 4 is a partial enlarged projection view in the vertical direction of a base according to one exemplary embodiment. Fig. 5 is an enlarged cross-sectional view of a substrate support according to another exemplary embodiment. Fig. 6 is an enlarged cross-sectional view of a substrate support according to yet another exemplary embodiment.

[0008] Various exemplary embodiments will be described in detail below with reference to the drawings, in which the same or equivalent parts are designated by the same reference numerals.

[0009] FIG. 1 is a diagram illustrating an exemplary configuration of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing system is an example of a substrate processing system, and the plasma processing apparatus 1 is an example of a substrate processing apparatus. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 (described later), and the gas exhaust port is connected to an exhaust system 40 (described later). The substrate support 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0010] 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). Various types of plasma generators may be used, including alternating current (AC) plasma generators and direct current (DC) plasma generators. In one embodiment, the AC signal (AC power) used in the AC plasma generator has a frequency in the range of 100 kHz to 10 GHz. Thus, AC signals include radio frequency (RF) signals and microwave signals. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0011] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform various processes described herein. In one embodiment, part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The control unit 2 may be implemented by, for example, a computer 2a. The processing unit 2a1 may be configured to read a program from the storage unit 2a2 and execute the read program to perform various control operations. This program may be stored in the storage unit 2a2 in advance or may be acquired via a medium when needed. The acquired program is stored in the storage unit 2a2 and read from the storage unit 2a2 by the processing unit 2a1 for execution. The medium may be various storage media readable by the computer 2a or a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). The storage unit 2a2 may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0012] The following describes a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 2 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus.

[0013] The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0014] The substrate support 11 includes a main body 5 and a ring assembly 112. The main body 5 has a central region 5a for supporting a substrate W and an annular region 5b for supporting the ring assembly 112. A wafer is an example of a substrate W. The annular region 5b of the main body 5 surrounds the central region 5a of the main body 5 in a plan view. The substrate W is disposed on the central region 5a of the main body 5, and the ring assembly 112 is disposed on the annular region 5b of the main body 5 so as to surround the substrate W on the central region 5a of the main body 5. Therefore, the central region 5a is also called a substrate support surface for supporting the substrate W, and the annular region 5b is also called a ring support surface for supporting the ring assembly 112.

[0015] In one embodiment, the main body 5 includes a base 50 and an electrostatic chuck 51. The base 50 includes a conductive member. The conductive member of the base 50 may function as a lower electrode. The electrostatic chuck 51 is disposed on the base 50. The electrostatic chuck 51 includes a ceramic member 51a and an electrostatic electrode 51b disposed within the ceramic member 51a. The ceramic member 51a has a central region 5a. In one embodiment, the ceramic member 51a also has an annular region 5b. Note that another member surrounding the electrostatic chuck 51, such as the annular electrostatic chuck or an annular insulating member, may also have the annular region 5b. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 51 and the annular insulating member. Furthermore, at least one RF / DC electrode coupled to an RF power source 31 and / or a DC power source 32 (described later) may be disposed within the ceramic member 51a. 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 at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. The conductive member of the base 50 and at least one RF / DC electrode may function as multiple lower electrodes. Alternatively, the electrostatic electrode 51b may function as the lower electrode. Therefore, the substrate support 11 includes at least one lower electrode.

[0016] The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one cover ring. The edge rings are formed of a conductive or insulating material, and the cover rings are formed of an insulating material.

[0017] The substrate support 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 51, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow passage 50a, or a combination thereof. A heat transfer fluid such as brine or a gas flows through the flow passage 50a. In one embodiment, the flow passage 50a is formed in the base 50, and one or more heaters are disposed in the ceramic member 51a of the electrostatic chuck 51. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas to a gap between the back surface of the substrate W and the central region 5a.

[0018] The showerhead 13 is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The process gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the multiple gas inlets 13c. The showerhead 13 also includes at least one upper electrode. In addition to the showerhead 13, the gas inlet may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0019] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one process gas from a corresponding gas source 21 to the showerhead 13 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include at least one flow modulation device that modulates or pulses the flow rate of the at least one process gas.

[0020] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power) to at least one lower electrode and / or at least one upper electrode. This generates a plasma from at least one processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of the plasma generation unit 12. Furthermore, by supplying a bias RF signal to the at least one lower electrode, a bias potential is generated on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0021] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to at least one lower electrode and / or at least one upper electrode via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generating unit 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to at least one lower electrode and / or at least one upper electrode.

[0022] The second RF generator 31b is coupled to at least one lower electrode via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0023] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to the at least one lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to the at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the at least one upper electrode.

[0024] In various embodiments, the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generator for generating the sequence of voltage pulses from the DC signal is connected between the first DC generator 32a and at least one lower electrode. Thus, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. When the second DC generator 32b and the waveform generator constitute a voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulses may have either positive or negative polarity. Furthermore, the sequence of voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses within one period. The first and second DC generating units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided instead of the second RF generating unit 31b.

[0025] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is regulated by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0026] 3 is an enlarged cross-sectional view of a substrate support according to an exemplary embodiment. As described above, the main body 5 is an example of a substrate support. The main body 5 includes a base 50, an electrostatic chuck 51, at least one protrusion, and an adhesive 52.

[0027] The base 50 includes a first main body 500. The first main body 500 has a substantially cylindrical shape. The first main body 500 has an upper surface 501 and a side surface. In the example shown in FIG. 3 , the upper surface 501 of the first main body 500 forms a part of the upper surface of the base 50. The side surface of the first main body 500 forms the side surface of the base 50. The first main body 500 provides a flow path 50a therein. In one example, the base 50 is formed from a metal including aluminum. The thermal conductivity of the base 50 may be 200 W / m·K or more. The first main body 500 is electrically conductive.

[0028] The first body 500 may be electrically connected to the plasma generating unit 12 to function as a lower electrode. The plasma generating unit 12 may be configured to supply source high frequency power to the base 50 to generate plasma in the chamber 10. The above-mentioned source RF signal is an example of source high frequency power. The plasma processing apparatus 1 may further include a bias power supply. The above-mentioned second RF generating unit 31b is an example of a bias power supply. The second RF generating unit 31b is electrically connected to the base 50 and configured to supply an electrical bias to the base 50 to attract ions from the plasma in the chamber 10.

[0029] The electrostatic chuck 51 is disposed on the base 50. The electrostatic chuck 51 includes a second body portion 510. The second body portion 510 has a generally circular disk shape. The second body portion 510 has an upper surface and a lower surface 511. The upper surface of the second body portion 510 constitutes the upper surface of the electrostatic chuck 51. The second body portion 510 is configured to hold a substrate W disposed thereon. The upper surface of the second body portion 510 may include a central region 5a and an annular region 5b. In the example shown in FIG. 3 , the lower surface 511 of the second body portion 510 constitutes the lower surface of the electrostatic chuck 51. In one example, the thermal conductivity of the second body portion 510 is 64 W / m·K or less, or 32 W / m·K or less. In one embodiment, the electrostatic chuck 51 may include an electrostatic electrode 51b. The electrostatic electrode 51b is disposed within the second body portion 510.

[0030] In one embodiment, the second body portion 510 may have a thickness of 0.5 mm or more and 1.0 mm or less. In one example, the minimum thickness between the upper surface (central region 5 a) of the second body portion 510 and the lower surface 511 of the second body portion 510 is 0.5 mm or more and 1.0 mm or less. The smaller the thickness of the second body portion 510, the closer the distance between the base 50 and the substrate W placed on the electrostatic chuck 51. As a result, the efficiency of the source RF power and the electrical bias applied to the substrate W using the base 50 as the lower electrode is improved. Note that the electrostatic chuck 51 does not necessarily have to include a lower electrode. The electrostatic chuck 51 does not necessarily have to include a heater.

[0031] As shown in Fig. 3 , in one embodiment, the main body 5 includes at least one protrusion protruding from the upper surface 501 of the first main body 500 toward the lower surface 511 of the second main body 510. In the example shown in Fig. 3 , the at least one protrusion includes a plurality of protrusions 53. An example in which the at least one protrusion includes a plurality of protrusions 53 will be described below. The surfaces of the plurality of protrusions 53 form part of the upper surface of the base 50. In the main body 5, the upper surface of the base 50 is formed by the upper surface 501 of the first main body 500 and the surfaces of the plurality of protrusions 53.

[0032] 4 is a partial enlarged vertical projection view of a base according to an exemplary embodiment. As shown in FIG. 4 , each of the multiple protrusions 53 has a circular shape in the vertical direction. Each of the multiple protrusions 53 may have a cylindrical shape including a side surface and a circular upper surface. The multiple protrusions 53 may be formed integrally with the base 50. When the multiple protrusions 53 are formed integrally with the base 50, the electrical distance between the base 50 and the substrate W placed on the electrostatic chuck 51 is shortened. As a result, the efficiency of the source RF power and the electrical bias applied to the substrate W using the base 50 as a lower electrode is improved.

[0033] In one embodiment, the distance from the upper surface 501 of the first body portion 500 to the tip of at least one of the protrusions may be 0.1 mm or more and 1.5 mm or less. In the example shown in FIG. 3 , the maximum distance from the upper surface 501 of the first body portion 500 to the tip of one of the plurality of protrusions 53 is 0.1 mm or more and 1.5 mm or less. The distance from the upper surface 501 of the first body portion 500 to the tip of each of the plurality of protrusions 53 may be within a range of 0.1 mm or more and 1.5 mm or less. The smaller the distance from the upper surface 501 of the first body portion 500 to the tip of each of the plurality of protrusions 53, the thinner the adhesive disposed in the gap defined by the plurality of protrusions 53. As a result, the temperature difference between the base 50 and the electrostatic chuck 51 is reduced.

[0034] In one embodiment, each of the plurality of protrusions 53 may have a shortest distance d between its side surface and the side surface of another protrusion located closest to it among the plurality of protrusions 53, the shortest distance being 1.0 mm or more and 5.0 mm or less. In one example, each of the plurality of protrusions 53 is cylindrical with a circular upper surface having a diameter of 1.0 mm or less, and the center-to-center distance of the cylindrical shapes of the plurality of protrusions 53 is 5.0 mm or more. In this case, the shortest distance d between the side surfaces of the plurality of protrusions 53 is 4.0 mm or more.

[0035] In one embodiment, the ratio of the projected area of ​​the plurality of protrusions 53 in the vertical direction to the projected area of ​​the base 50 in the vertical direction is 10% or less. In the example shown in FIG. 4 , each of the plurality of protrusions 53 has a cylindrical shape including a circular upper surface with a diameter of 1.0 mm or less. The center-to-center distance of each of the cylindrical shapes of the plurality of protrusions 53 is 5.0 mm or more. In this case, the shortest distance d between each side surface of the plurality of protrusions 53 is 4.0 mm or more, and the ratio of the projected area of ​​the plurality of protrusions 53 in the vertical direction to the projected area of ​​the base 50 in the vertical direction is 9.1% or less.

[0036] The plurality of protrusions 53 define a gap between the upper surface 501 of the first body portion 500 and the lower surface 511 of the second body portion 510. The adhesive 52 is disposed in the gap between the upper surface 501 and the lower surface 511. The adhesive 52 bonds the electrostatic chuck 51 to the base 50. The adhesive 52 secures the upper surface 501 of the first body portion 500 and the lower surface 511 of the second body portion 510 to each other. The electrostatic chuck 51 is secured to the base 50 by the adhesive 52. In one example, the thermal conductivity of the adhesive 52 is 2.8 W / m·K or less, or 1.4 W / m·K or less. The thermal conductivity of the adhesive 52 may be 1 / 100 or less of the thermal conductivity of the base 50.

[0037] The main body 5 (substrate support) has a plurality of protrusions 53 protruding from an upper surface 501 of the first main body 500 toward a lower surface 511 of the second main body 510. The tip of each of the plurality of protrusions 53 is closer to the lower surface 511 of the second main body 510 than the upper surface 501 of the first main body 500 and the lower surface 511 of the second main body 510. The distance between the tip of each of the plurality of protrusions 53 and the lower surface 511 of the second main body 510 is smaller than the distance between the upper surface 501 of the first main body 500 and the lower surface 511 of the second main body 510. Therefore, the thermal resistance between the tip of each of the plurality of protrusions 53 and the lower surface 511 of the second main body 510 is smaller than the thermal resistance between the upper surface 501 of the first main body 500 and the lower surface 511 of the second main body 510. As a result, the substrate support (main body 5 ) reduces the temperature difference between the base 50 and the electrostatic chuck 51 .

[0038] The smaller the thickness of the second body portion 510, the smaller the temperature difference between the base 50 and the electrostatic chuck 51. Since the second body portion 510 has a thickness of 0.5 mm or more and 1.0 mm or less, the temperature difference between the base 50 and the electrostatic chuck 51 can be more easily reduced than with a conventional substrate support. In a first comparative experiment, a comparative substrate support that did not have at least one protrusion and had a second body portion having a thickness of 4.6 mm had a temperature difference of 21.6°C between the upper surface of the base and the upper surface of the electrostatic chuck. In a second comparative experiment, a comparative substrate support that did not have multiple protrusions 53 and had a second body portion having a thickness of 1.2 mm had a temperature difference of 11.0°C between the upper surface of the base and the upper surface of the electrostatic chuck. In an experiment according to the present disclosure, in a substrate support having a plurality of protrusions 53 and a second main body portion 510 having a thickness of 1.0 mm, the temperature difference between the upper surface 501 of the first main body portion 500 of the base 50 and the upper surface of the electrostatic chuck 51 was 5.7°C.

[0039] In the main body 5, each of the plurality of protrusions 53 has a shortest distance d between its side surface and the side surface of the nearest other protrusion among the plurality of protrusions 53, the shortest distance d being 1.0 mm or more and 5.0 mm or less. In this case, the pitch between the plurality of protrusions is 5.0 mm or less, thereby suppressing temperature variations on the electrostatic chuck 51. In a third comparative experiment, when the plurality of protrusions 53 each had a shortest distance d of 15 mm and the pitch between the plurality of protrusions was 15 mm, the temperature variations on the electrostatic chuck 51 were 13°C or more. In a fourth comparative experiment, when the plurality of protrusions 53 each had a shortest distance d of 10 mm and the pitch between the plurality of protrusions was 10 mm, the temperature variations on the electrostatic chuck 51 were 11°C or more. In experiments according to the present disclosure, when the plurality of protrusions 53 each had a shortest distance d of 4 mm and the pitch between the plurality of protrusions was 4 mm, the temperature variations on the electrostatic chuck 51 were 8°C or less.

[0040] A substrate support according to another exemplary embodiment will be described below. The substrate support (main body 5A) according to another exemplary embodiment will be described below from the viewpoint of differences from the substrate support (main body 5) shown in FIG. 3, and duplicated descriptions will be omitted as appropriate.

[0041] Fig. 5 is an enlarged cross-sectional view of a substrate support according to another exemplary embodiment. In the example shown in Fig. 5, an upper surface 501 of a first body portion 500 constitutes an upper surface of a base 50. A lower surface 511 of a second body portion 510 constitutes a part of a lower surface of an electrostatic chuck 51. The body portion 5A includes at least one protrusion protruding from the lower surface 511 of the second body portion 510 toward the upper surface 501 of the first body portion 500. In the example shown in Fig. 5, the at least one protrusion includes a plurality of protrusions 53 adjacent to each other.

[0042] In one embodiment, the distance from the lower surface 511 of the second main body portion 510 to the tip of at least one of the protrusions may be 0.1 mm or more and 1.5 mm or less. In the example shown in FIG. 5 , the maximum distance from the lower surface 511 of the second main body portion 510 to the tip of one of the plurality of protrusions 53 is 0.1 mm or more and 1.5 mm or less. The distance from the lower surface 511 of the second main body portion 510 to the tip of each of the plurality of protrusions 53 may be within a range of 0.1 mm or more and 1.5 mm or less. Note that, in the plurality of protrusions 53 included in the main body portion 5A, each of the plurality of protrusions 53 may have a shortest distance d between its side surface and the side surface of the other protrusion that is closest to it among the plurality of protrusions 53, which may be 1.0 mm or more and 5.0 mm or less.

[0043] The substrate support (main body portion 5A) includes a plurality of protrusions 53 protruding from a lower surface 511 of the second main body portion 510 toward an upper surface 501 of the first main body portion 500. The tip of each of the plurality of protrusions 53 is closer to the upper surface 501 of the first main body portion 500 than the lower surface 511 of the second main body portion 510 and the upper surface 501 of the first main body portion 500. The distance between the tip of each of the plurality of protrusions 53 and the upper surface 501 of the first main body portion 500 is smaller than the distance between the lower surface 511 of the second main body portion 510 and the upper surface 501 of the first main body portion 500. Therefore, the thermal resistance between the tip of each of the plurality of protrusions 53 and the upper surface 501 of the first main body portion 500 is smaller than the thermal resistance between the lower surface 511 of the second main body portion 510 and the upper surface 501 of the first main body portion 500. As a result, the substrate support (main body portion 5A) reduces the temperature difference between the base 50 and the electrostatic chuck 51.

[0044] A substrate support according to yet another exemplary embodiment will be described below. The substrate support (main body 5B) according to yet another exemplary embodiment will be described below from the perspective of differences from the substrate support (main body 5) shown in FIG. 3, and duplicated descriptions will be omitted as appropriate.

[0045] FIG. 6 is an enlarged cross-sectional view of a substrate support according to another exemplary embodiment. As shown in FIG. 6 , in one embodiment, the main body portion 5B includes a heat-conductive layer 54. The heat-conductive layer 54 is disposed between the lower surface 511 of the second main body portion 510 and the plurality of protrusions 53. The heat-conductive layer 54 is formed of metal. In one example, the heat-conductive layer 54 is a metal film formed on the surface of a dielectric member. The heat-conductive layer 54 may be formed by sputtering, vapor deposition, or cold spraying. The thermal conductivity of the heat-conductive layer 54 is higher than that of the dielectric member. In one example, the thermal conductivity of the heat-conductive layer 54 is 100 W / m·K or greater. In the main body portion 5B, the adhesive 52 bonds the electrostatic chuck 51 to the base 50 via the heat-conductive layer 54. The adhesive 52 fixes the upper surface 501 of the first main body portion 500 and the heat-conductive layer 54 to each other.

[0046] In the substrate support (main body portion 5B), a heat transfer layer 54 is disposed between the lower surface 511 of the second main body portion 510 and the plurality of protrusions 53. The thermal conductivity of the heat transfer layer 54 is higher than the thermal conductivity of the second main body portion 510. Therefore, the thermal resistance between the tip of each of the plurality of protrusions 53 and the heat transfer layer 54 is even smaller. As a result, the substrate support (main body portion 5B) further reduces the temperature difference between the base 50 and the electrostatic chuck 51.

[0047] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and modifications may be made. Furthermore, elements in different embodiments may be combined to form other embodiments.

[0048] The substrate support may include at least one convex portion protruding from one of the upper surface 501 of the first body portion 500 and the lower surface 511 of the second body portion 510 toward the other of the upper surface 501 of the first body portion 500 and the lower surface 511 of the second body portion 510. The substrate support may include both at least one convex portion protruding from the upper surface 501 of the first body portion 500 toward the lower surface 511 of the second body portion 510 and at least one convex portion protruding from the lower surface 511 of the second body portion 510 toward the upper surface 501 of the first body portion 500.

[0049] Each of the plurality of protrusions 53 may have a truncated cone shape including a side surface and a circular upper surface, which improves the efficiency of heat exchange on the upper surface of each of the plurality of protrusions 53 and ensures a gap in which the adhesive 52 is disposed.

[0050] The at least one protrusion may be a single protrusion. In one example, the single protrusion may define a groove as a gap between the upper surface 501 of the first body portion 500 and the lower surface 511 of the second body portion 510. In the vertical direction, the groove may have a spiral shape or a radial shape.

[0051] As described above, the heat transfer layer 54 may be disposed between at least one protrusion protruding from the upper surface 501 of the first body portion 500 toward the lower surface 511 of the second body portion 510 and the lower surface 511 of the second body portion 510. In this case, the heat transfer layer 54 may cover the lower surface 511 of the second body portion 510. The heat transfer layer 54 may be disposed between at least one protrusion protruding from the lower surface 511 of the second body portion 510 toward the upper surface 501 of the first body portion 500 and the upper surface 501 of the first body portion 500. In this case, the heat transfer layer 54 may cover only the tip of the at least one protrusion. The heat transfer layer 54 may cover the surface of the at least one protrusion and the lower surface 511 of the second body portion 510. The heat transfer layer 54 may be disposed along the lower surface of the electrostatic chuck 51.

[0052] Various exemplary embodiments included in the present disclosure are now described in [E1] to [E11] below.

[0053] [E1] A substrate support comprising: a base including a first body portion having an upper surface; an electrostatic chuck disposed on the base, the electrostatic chuck including a second body portion having a lower surface and a thickness of 0.5 mm or more and 1.0 mm or less, the second body portion being configured to hold a substrate disposed thereon; at least one protrusion protruding from one of the upper surface of the first body portion and the lower surface of the second body portion toward the other of the upper surface of the first body portion and the lower surface of the second body portion, the at least one protrusion defining a gap between the upper surface of the first body portion and the lower surface of the second body portion; and an adhesive disposed in the gap, bonding the electrostatic chuck to the base. [E2] A substrate support comprising: a base including a first body portion having an upper surface, an electrostatic chuck including a second body portion having a lower surface and configured to hold a substrate disposed thereon, the electrostatic chuck being disposed on the base, at least one protrusion protruding from one of the upper surface of the first body portion and the lower surface of the second body portion toward the other of the upper surface of the first body portion and the lower surface of the second body portion, the at least one protrusion defining a gap between the upper surface of the first body portion and the lower surface of the second body portion, a heat transfer layer having a thermal conductivity higher than that of the second body portion and disposed between the other of the upper surface of the first body portion and the lower surface of the second body portion and the at least one protrusion, and an adhesive disposed in the gap and bonding the electrostatic chuck to the base. [E3] The substrate support according to E1 or E2, wherein the at least one protrusion protrudes from the upper surface of the first body portion toward the lower surface of the second body portion. [E4] The substrate support according to E1 or 2, wherein the at least one protrusion protrudes from the lower surface of the second main body portion toward the upper surface of the first main body portion. [E5] The substrate support according to any one of E1 to E4, wherein a distance from one of the upper surface of the first main body portion or the lower surface of the second main body portion to a tip of the at least one protrusion is 0.1 mm or more and 1.5 mm or less.[E6] The substrate support according to any one of E1 to E5, wherein the at least one protrusion includes a plurality of protrusions, and each of the plurality of protrusions has a shortest distance between its side surface and a side surface of another protrusion among the plurality of protrusions that is closest to it, the shortest distance being 1.0 mm or more and 5.0 mm or less. [E7] The substrate support according to any one of E1 to E6, wherein a ratio of a projected area of ​​the at least one protrusion in the vertical direction to a projected area of ​​the base in the vertical direction is 10% or less. [E8] The substrate support according to any one of E1 to E7, wherein the electrostatic chuck has an electrostatic electrode, and the electrostatic electrode is disposed within the second main body portion. [E9] A substrate processing apparatus comprising: a chamber; the substrate support according to any one of E1 to E8, disposed within the chamber; and a plasma generation unit configured to generate plasma within the chamber. [E10] The substrate processing apparatus of E9, wherein the plasma generating unit is configured to supply source radio frequency power to the base to generate the plasma in the chamber. [E11] The substrate processing apparatus of E9 or E10, further comprising a bias power supply electrically connected to the base and configured to supply an electrical bias to the base to attract ions from the plasma in the chamber.

[0054] From the foregoing, it will be understood that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the appended claims.

[0055] 1...plasma processing apparatus, 12...plasma generation unit, 10...chamber, 50...base, 500...first main body, 501...upper surface, 51...electrostatic chuck, 510...second main body, 511...lower surface, 51b...electrostatic electrode, 52...adhesive, 53...multiple convex portions, 54...heat transfer layer, d...shortest distance, W...substrate.

Claims

1. A substrate support comprising: a base including a first body having an upper surface; an electrostatic chuck disposed on the base, the second body having a lower surface and a thickness of 0.5 mm or more and 1.0 mm or less, the second body being configured to hold a substrate disposed thereon; at least one protrusion protruding from one of the upper surface of the first body and the lower surface of the second body toward the other of the upper surface of the first body and the lower surface of the second body, the at least one protrusion defining a gap between the upper surface of the first body and the lower surface of the second body; and an adhesive disposed in the gap, bonding the electrostatic chuck to the base.

2. A substrate support comprising: a base including a first body portion having an upper surface; an electrostatic chuck disposed on the base, the electrostatic chuck including a second body portion having a lower surface and configured to hold a substrate disposed thereon; at least one protrusion protruding from one of the upper surface of the first body portion and the lower surface of the second body portion toward the other of the upper surface of the first body portion and the lower surface of the second body portion, the at least one protrusion defining a gap between the upper surface of the first body portion and the lower surface of the second body portion; a heat transfer layer having a thermal conductivity higher than that of the second body portion, the heat transfer layer being disposed between the other of the upper surface of the first body portion and the lower surface of the second body portion and the at least one protrusion; and an adhesive disposed in the gap for adhering the electrostatic chuck to the base.

3. The substrate support according to claim 1 or 2, wherein the at least one protrusion protrudes from the upper surface of the first body portion toward the lower surface of the second body portion.

4. The substrate support according to claim 1 or 2, wherein the at least one protrusion protrudes from the lower surface of the second body portion toward the upper surface of the first body portion.

5. A substrate support according to claim 1 or 2, wherein the distance from either the upper surface of the first main body portion or the lower surface of the second main body portion to the tip of the at least one protrusion is 0.1 mm or more and 1.5 mm or less.

6. A substrate support according to claim 1 or 2, wherein the at least one protrusion includes a plurality of protrusions, and each of the plurality of protrusions has a shortest distance between its side surface and the side surface of another protrusion among the plurality of protrusions that is located nearest thereto of 1.0 mm or more and 5.0 mm or less.

7. The substrate support according to claim 1 or 2, wherein a ratio of a projected area of ​​said at least one convex portion in the vertical direction to a projected area of ​​said base in the vertical direction is 10% or less.

8. The substrate support according to claim 1 or 2, wherein the electrostatic chuck has an electrostatic electrode, and the electrostatic electrode is disposed within the second body portion.

9. A substrate processing apparatus comprising: a chamber; a substrate support according to claim 1 or 2 disposed in the chamber; and a plasma generating unit configured to generate plasma in the chamber.

10. The substrate processing apparatus according to claim 9, wherein the plasma generating unit is configured to supply source high frequency power to the base to generate the plasma in the chamber.

11. The substrate processing apparatus of claim 9, further comprising a bias power supply electrically connected to the pedestal and configured to provide an electrical bias to the pedestal to attract ions from the plasma in the chamber.

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