Electrostatic chuck and substrate processing apparatus

Abstract

To provide an electrostatic chuck and a substrate processing apparatus that suppress residual adhesion of a substrate.SOLUTION: An electrostatic chuck includes a dielectric and an electrode provided inside the dielectric, and the dielectric has a first main surface, a contact support portion that protrudes beyond the first main surface and contacts the back surface of a substrate to support the substrate, and a groove portion that is provided between the first main surface and the contact support portion so as to surround the contact support portion.SELECTED DRAWING: Figure 6

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a holding device provided with a ceramic member having a recess and a plurality of protrusions (a peripheral seal band and columnar protrusions) formed on an adsorption surface.

[0003] Patent Document 2 discloses that residual charges accumulate on the surface of the electrostatic chuck, causing the substrate to be residually attracted. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-129632 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-149935 Summary of the Invention [Problem to be solved by the invention]

[0005] In one aspect, the present disclosure provides an electrostatic chuck and a substrate processing apparatus that suppress residual adhesion of a substrate. [Means for solving the problem]

[0006] In order to solve the above problem, according to one aspect, there is provided an electrostatic chuck comprising a dielectric and an electrode provided inside the dielectric, wherein the dielectric has a first main surface, a contact support portion that protrudes beyond the first main surface and contacts a back surface of a substrate to support the substrate, and a groove portion that is provided between the first main surface and the contact support portion so as to surround the contact support portion. [Effects of the Invention]

[0007] According to one aspect, it is possible to provide an electrostatic chuck and a substrate processing apparatus that suppress residual adhesion of a substrate. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is an example of a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus. [Figure 2] FIG. 1 is an example of a plan view of an electrostatic chuck according to an embodiment. [Figure 3] 2 is an example of an AA cross-sectional view of an electrostatic chuck according to an embodiment. [Figure 4] FIG. 10 is a plan view of an electrostatic chuck according to a reference example. [Figure 5] FIG. 10 is an example of a BB cross-sectional view of an electrostatic chuck according to a reference example. [Figure 6] FIG. 2 is an example of a partially enlarged cross-sectional view illustrating a substrate holding state in an electrostatic chuck according to an embodiment. [Figure 7] FIG. 10 is an example of a partially enlarged cross-sectional view showing a substrate holding state in the electrostatic chuck according to the reference example. [Figure 8] FIG. 10 is another example of a partially enlarged cross-sectional view illustrating a substrate holding state in the electrostatic chuck according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0010] An example of the configuration of a plasma processing system will be described below: Fig. 1 is an example of a diagram for explaining an example of the configuration of a capacitively coupled plasma processing apparatus (substrate processing apparatus) 1.

[0011] The plasma processing system includes a capacitively coupled plasma processing device 1 and a controller 2. The capacitively coupled plasma processing device 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing device 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 has at least one gas inlet for supplying at least one process gas to the plasma processing space 10s and at least one gas outlet for exhausting gas from the plasma processing space 10s. The plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support 11 are electrically isolated from the plasma processing chamber 10 enclosure.

[0012] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region 111a for supporting a substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. Therefore, the central region 111a is also called a substrate support surface for supporting the substrate W, and the annular region 111b is also called a ring support surface for supporting the ring assembly 112.

[0013] In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 can function as a lower electrode. The electrostatic chuck 1111 is disposed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Note that the annular region 111b may also be provided by another member surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. Furthermore, at least one RF / DC electrode coupled to an RF (Radio Frequency) power supply 31 and / or a DC (Direct Current) power supply 32 (described later) may be disposed within the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or a DC signal (described later) is supplied to the at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as multiple lower electrodes. Alternatively, the electrostatic electrode 1111b may function as the lower electrode. Therefore, the substrate support 11 includes at least one lower electrode.

[0014] 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.

[0015] The substrate support 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow path 1110a, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path 1110a. In one embodiment, the flow path 1110a is formed in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. The substrate support 11 may also include a heat transfer gas supply unit 15 configured to supply a heat transfer gas to a gap between the back surface of the substrate W and the central region 111a. The heat transfer gas supply unit 15 supplies a heat transfer gas, such as He gas, through the flow path 14 between the back surface of the substrate W placed on the electrostatic chuck 1111 and a first main surface (recessed surface 121 described below) of the electrostatic chuck 1111.

[0016] The showerhead 13 is configured to 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 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 showerhead 13 also includes at least one upper electrode. In addition to the showerhead 13, the gas introduction unit may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0017] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one process gas from a corresponding gas source 21 to the showerhead 13 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include one or more flow modulation devices to modulate or pulse the flow rate of the at least one process gas.

[0018] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power) to at least one lower electrode and / or at least one upper electrode. This generates a plasma from at least one process gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of a plasma generating unit configured to generate a plasma from one or more process gases in the plasma processing chamber 10. In addition, 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.

[0019] 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.

[0020] The second RF generating unit 31b is coupled to at least one lower electrode via at least one impedance matching circuit and 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 generating unit 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.

[0021] 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 at least one lower electrode and configured to generate a first DC signal. The generated first bias DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to 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.

[0022] In various embodiments, at least one of the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generator for generating a 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.

[0023] 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 regulating valve regulates the pressure in the plasma processing space 10s. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0024] The controller 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The controller 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 controller 2 may be included in the plasma processing apparatus 1. The controller 2 may include a processor 2a1, a storage unit 2a2, and a communication interface 2a3. The controller 2 may be implemented by, for example, a computer 2a. The processor 2a1 may be configured to read a program from the storage unit 2a2 and execute the read program to perform various control operations. The 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 processor 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 processor 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).

[0025] Next, the electrostatic chuck 1111 will be further described with reference to Figures 2 and 3. Figure 2 is an example of a plan view of the electrostatic chuck 1111 according to an embodiment. Figure 3 is an example of an AA cross-sectional view of the electrostatic chuck 1111 according to an embodiment.

[0026] The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b. The ceramic member 1111a is made of a dielectric material. The electrostatic electrode 1111b is disposed within the ceramic member 1111a.

[0027] The central region 111a of the electrostatic chuck 1111 has a recessed surface (first main surface) 121, dots 122, and a seal band 123.

[0028] The recessed surface 121 is a surface that is dug deeper than the upper surfaces of the dots 122 (the surface on which the substrate W is placed) and the upper surface of the seal band 123 (the surface on which the substrate W is placed). The recessed surface 121 is a surface that faces the back surface of the substrate W while being spaced apart from it when the substrate W is placed on the electrostatic chuck 1111 (see FIG. 6, which will be described later). The surface of the recessed surface 121 is a processed surface that has been subjected to blasting and polishing. The surface of the recessed surface 121 is a processed surface having an arithmetic mean roughness Ra of 0.1 (μm), for example.

[0029] The electrostatic chuck 1111 also has a flow path 141 and an opening 142. The flow path 141 is formed to penetrate the electrostatic chuck 1111, and a heat transfer gas is supplied from a heat transfer gas supply unit 15 (see FIG. 1) via a flow path 14 (see FIG. 1). The opening 142 is formed in the recessed surface 121.

[0030] In the central region 111a of the electrostatic chuck 1111, dots 122 and a seal band 123 are formed as contact support portions that protrude from the recessed surface 121.

[0031] The dots 122 are formed in a generally cylindrical shape protruding from the recessed surface 121. When the electrostatic chuck 1111 is viewed from above (see FIG. 2), a plurality of dots 122 are formed in an area inside a ring-shaped seal band 123 formed on the periphery of the central region 111a. When the substrate W is placed on the electrostatic chuck 1111 (see FIG. 6, which will be described later), the upper surfaces of the dots 122 come into contact with the back surface of the substrate W, supporting the inner area of ​​the substrate W. The upper surfaces of the dots 122 are processed surfaces that have been subjected to a polishing process. The upper surfaces of the dots 122 are processed surfaces having an arithmetic mean roughness Ra of, for example, 0.01 (μm).

[0032] The seal band 123 is formed in a ring shape, protruding from the recessed surface 121 and following the outer periphery of the central region 111a. When the substrate W is placed on the electrostatic chuck 1111 (see FIG. 6 described later), the upper surface of the seal band 123 comes into contact with the back surface of the substrate W, supporting the outer region of the substrate W. The upper surface of the seal band 123 is a processed surface that has been subjected to a polishing process. The upper surface of the seal band 123 is a processed surface having an arithmetic mean roughness Ra of, for example, 0.01 (μm).

[0033] Furthermore, when the substrate W is placed on the electrostatic chuck 1111 (see FIG. 6 described later), the seal band 123 forms a space (gap) with the back surface of the substrate W, the recessed surface 121 of the electrostatic chuck 1111, and the inner peripheral surface of the seal band 123. The heat transfer gas supplied from the heat transfer gas supply unit 15 is supplied to this space through the flow paths 14 and 141 and from openings 142 formed in the recessed surface 121.

[0034] In the central region 111a of the electrostatic chuck 1111, grooves 124 and 125 are formed by digging down from the recessed surface 121.

[0035] The grooves 124 are formed so as to surround the dots 122. In other words, the grooves 124 are formed between the upper surfaces of the dots 122 and the recessed surface 121. The grooves 124 are also formed directly above the electrostatic electrodes 1111b.

[0036] The groove 125 is formed so as to surround the inner periphery of the seal band 123. In other words, the groove 124 is formed between the upper surface of the dot 122 and the recessed surface 121. The groove 125 is also formed directly above the electrostatic electrode 1111b.

[0037] The electrostatic chuck 1111 has a plurality of contact support portions (dots 122, seal bands 123), and the grooves 124, 125 are provided corresponding to each of the plurality of contact support portions (dots 122, seal bands 123). The plurality of grooves 124, 125 are provided continuously so as to surround the contact support portions. However, the grooves 124, 125 may be provided discretely. In other words, a single contact support portion 122, 123 may be provided so as to be surrounded by a plurality of grooves 124, 125.

[0038] The bottom surfaces of the grooves 124 and 125 are formed at positions closer to the electrostatic electrode 1111b than the recessed surface 121. The bottom surfaces of the grooves 124 and 125 are formed at positions closer to the electrostatic electrode 1111b than the contact surfaces (top surfaces of the dots 122 and the seal band 123) on which the substrate W is placed. The recessed surface 121 is formed at a position closer to the electrostatic electrode 1111b than the contact surfaces (top surfaces of the dots 122 and the seal band 123) on which the substrate W is placed.

[0039] The width of the grooves 124, 125 is preferably, for example, 5 μm or more and 150 μm or less. By making the width of the grooves 124, 125 150 μm or less, a large area of ​​the carved surface 121 that contributes to the chucking force when electrostatically chucking the substrate W can be ensured. Furthermore, by making the width of the grooves 124, 125 5 μm or more, the formation of the grooves 124, 125 can be facilitated. The grooves 124, 125 are formed by, for example, groove cutting using a laser.

[0040] In addition, the area of ​​the grooves 124 and 125 is preferably 10% or less of the area of ​​the dug surface 121 in plan view (see FIG. 2).

[0041] Furthermore, the width of groove 125 is preferably wider than the width of groove 124. Specifically, the width of groove 125 is preferably 1.5 times wider than the width of groove 124 or more.

[0042] The depth of the grooves 124, 125 is preferably at least twice the roughness of the dug surface 121. The depth of the grooves 124, 125 is preferably, for example, 10 μm or more and 100 μm or less.

[0043] Next, an electrostatic chuck 1111C according to a reference example will be described with reference to Fig. 4 and Fig. 5. Fig. 4 is an example of a plan view of the electrostatic chuck 1111C according to the reference example. Fig. 5 is an example of a B-B cross-sectional view of the electrostatic chuck 1111C according to the reference example.

[0044] The electrostatic chuck 1111C according to the reference example has a central region 111a including a recessed surface 121, dots 122, and a seal band 123. That is, it is different in that it does not have grooves 124 and 125. The other configurations are similar, and therefore, redundant explanations will be omitted.

[0045] Next, the electrostatic chuck 1111 according to one embodiment will be further described in comparison with an electrostatic chuck 1111C according to a reference example. Fig. 6 is an example of a partially enlarged cross-sectional view showing a substrate holding state in the electrostatic chuck 1111 according to one embodiment. Fig. 7 is an example of a partially enlarged cross-sectional view showing a substrate holding state in the electrostatic chuck 1111 according to the reference example.

[0046] When attracting the substrate W, an attraction voltage (e.g., 2.5 kV) is applied to the electrostatic electrode 1111b to induce an electric charge on the substrate W. A Coulomb force is generated by the potential difference between the induced electric charge on the substrate W and the electrostatic electrode 1111b, and the substrate W is electrostatically attracted to the electrostatic chuck 1111 (1111C). In addition, the attraction is released by stopping the application of the attraction voltage to the electrostatic electrode 1111b.

[0047] Here, a film of reaction by-products may be formed on the surface of the electrostatic chuck 1111 (1111C) when the substrate W is processed. If the insulating properties of the reaction by-product film are low, in a high-temperature process or a long-term process, electric charges 200 leak from the contact surface on which the substrate W is placed (the upper surfaces of the dots 122 and the seal band 123), as shown by the arrows in Figures 6 and 7, and the electric charges 200 move downward due to the attraction voltage applied to the electrostatic electrode 1111b and the self-bias voltage of the plasma.

[0048] In the electrostatic chuck 1111C shown in FIG. 7, the electric charge 200 leaking from the contact surface (the upper surface of the dots 122 and the upper surface of the seal band 123) on which the substrate W is placed is transferred to the recessed surface 121 that is not in contact with the substrate W by the attraction voltage applied to the electrostatic electrode 1111b, and the electric charge 200 accumulates on the recessed surface 121.

[0049] As a result, a Coulomb force is generated between the charge on the substrate W and the charge 200 accumulated on the recessed surface 121, and there is a risk that electrostatic attraction between the substrate W and the electrostatic chuck 1111C may be maintained (residual attraction may occur) even if the application of an attraction voltage to the electrostatic electrode 1111b is stopped. On the other hand, in order to reduce the charge leaking from the substrate W to the contact support part, it is conceivable to reduce the contact area between the contact support part (the dots 122 and the seal band 123) and the substrate W, but this may result in a decrease in the attraction force to the substrate W and the sealing performance of the heat transfer gas.

[0050] Furthermore, if the attracting voltage is continuously applied to the electrostatic electrode 1111b, the electric charge 200 accumulated on the recessed surface 121 increases, thereby reducing the Coulomb force between the substrate W and the electrostatic chuck 1111C. As a result, even if the attracting voltage is applied to the electrostatic electrode 1111b, the pressure of the heat transfer gas may cause the substrate W to peel off from the electrostatic chuck 1111C.

[0051] 6, electric charges 200 leaking from the contact surfaces (upper surfaces of the dots 122 and the seal band 123) on which the substrate W is placed are moved to the bottom surfaces of the grooves 124 and 125 by the attraction voltage applied to the electrostatic electrode 1111b, and the electric charges 200 accumulate on the bottom surfaces of the grooves 124 and 125. The recessed surface 121 is formed at a position farther away (higher) from the electrostatic electrode 1111b than the bottom surfaces of the grooves 124 and 125. Therefore, the electric charges 200 that have moved to the bottom surfaces of the grooves 124 and 125 are prevented from moving to the recessed surface 121 by the attraction voltage applied to the electrostatic electrode 1111b, etc.

[0052] Here, the Coulomb force is proportional to the area of ​​the surface on which the charge 200 accumulates and inversely proportional to the distance between the back surface of the substrate W and the surface on which the charge 200 accumulates. The surface on which the charge 200 accumulates in the electrostatic chuck 1111 is the bottom surface of the grooves 124 and 125. The surface on which the charge 200 accumulates in the electrostatic chuck 1111C is the recessed surface 121. Therefore, the electrostatic chuck 1111 can reduce the area of ​​the surface on which the charge 200 accumulates and reduce the Coulomb force. Furthermore, the electrostatic chuck 1111 can increase the distance between the back surface of the substrate W and the surface on which the charge 200 accumulates and reduce the Coulomb force. This can reduce the residual chucking force.

[0053] For example, if the area of ​​grooves 124, 125 is 10% of the area of ​​dug surface 121 and the width of grooves 124, 125 is 70 μm, the residual suction force will be approximately 1 / 40 when the depth of grooves 124, 125 (the distance from dug surface 121 to the bottom of grooves 124, 125) is 10 to 20 μm, the residual suction force will be approximately 1 / 45 when the depth of grooves 124, 125 is 20 to 50 μm, and the residual suction force will be approximately 1 / 50 when the depth of grooves 124, 125 is 50 to 100 μm. Furthermore, if the width of grooves 124, 125 is 700 μm, the residual suction force will be approximately 1 / 100 when the depth of grooves 124, 125 is 10 to 20 μm, the residual suction force will be approximately 1 / 110 when the depth of grooves 124, 125 is 20 to 50 μm, and the residual suction force will be approximately 1 / 150 when the depth of grooves 124, 125 is 50 to 100 μm.

[0054] Furthermore, even if the attracting voltage is continuously applied to the electrostatic electrode 1111b and electric charge 200 accumulates on the bottom surfaces of the grooves 124 and 125, the electric charge 200 can be prevented from accumulating on the indented surface 121, and the substrate W can be electrostatically attracted by the indented surface 121. This prevents the substrate W from peeling off from the electrostatic chuck 1111C when the attracting voltage is applied to the electrostatic electrode 1111b. This ensures the pressure of the heat transfer gas, thereby ensuring the cooling performance of the substrate W. Furthermore, the width of the seal band 123 can be ensured, thereby ensuring the sealing performance of the heat transfer gas.

[0055] Furthermore, when the substrate W is released from the attraction, a process of reducing the residual attraction force is performed by applying a voltage (e.g., −500 V) opposite to the attraction voltage to the electrostatic electrode 1111b. In the electrostatic chuck 1111 shown in FIG. 6, charges 200 accumulate on the bottom surfaces of the small-area grooves 124 and 125, resulting in a high charge density. Furthermore, the grooves 124 and 125 are provided directly above the electrostatic electrode 1111b. This improves the efficiency of removing the charges 200 when the process of reducing the residual attraction force is performed.

[0056] Furthermore, it is preferable that the width of the groove 125 is wider than the width of the groove 124. This allows charges leaking from the seal band 123, which has a large contact area with the substrate W, to be accumulated in the groove 125.

[0057] Although the electrostatic chuck 1111 has been described as being provided with the grooves 124 and 125, the present invention is not limited to this.

[0058] It is also possible to form only grooves 125 surrounding the inner periphery of seal band 123, and omit grooves 124 surrounding dots 122. For example, when the number of dots 122 is small, in other words, when the sum of the areas of the upper surfaces of the multiple dots 122 in contact with substrate W is sufficiently small compared to the area of ​​the upper surface of seal band 123 in contact with substrate W, the amount of charge leaking from the upper surface of dots 122 is small compared to the amount of charge leaking from the upper surface of seal band 123. In such a configuration, it is also possible to form only grooves 125 surrounding the inner periphery of seal band 123.

[0059] Furthermore, a parallel surface may be provided between the contact surface on which the substrate W is placed (the upper surface of the dots 122, the upper surface of the seal band 123) and the bottom surface of the grooves 124, 125. This parallel surface may be formed at the same height as the recessed surface 121. The area of ​​this parallel surface is formed to be smaller than the area of ​​the recessed surface 121. Even in this configuration, the electric charge 200 leaking from the contact surface on which the substrate W is placed (the upper surface of the dots 122, the upper surface of the seal band 123) moves to the parallel surface due to an attraction voltage applied to the electrostatic electrode 1111b, and further moves to the bottom surface of the grooves 124, 125, where the electric charge 200 accumulates.

[0060] In addition, although the groove 125 is formed so as to surround the inner periphery of the seal band 123 in the above description, the present invention is not limited to this. Fig. 8 is another example of a partially enlarged cross-sectional view showing a substrate holding state in the electrostatic chuck 1111 according to an embodiment. As shown in Fig. 8, the groove 126 may be formed so as to surround the outer periphery of the seal band 123.

[0061] Although the electrostatic chuck 1111 has been described as having a configuration in which the substrate W is attracted by Coulomb force, the present invention is not limited to this configuration and may also be applied to a configuration in which the substrate W is attracted by the Johnson-Rahbek effect. Furthermore, the electrostatic electrode 1111b of the electrostatic chuck 1111 has been described as having a monopolar configuration, but the present invention is not limited to this configuration and may have a multipolar configuration, or may have a monopolar or bipolar configuration.

[0062] The above-disclosed embodiments include, for example, the following aspects. (Appendix 1) a dielectric; an electrode provided inside the dielectric, The dielectric material is A first principal surface; a contact support portion that protrudes beyond the first main surface and contacts a rear surface of the substrate to support the substrate; a groove portion provided between the first main surface and the contact support portion so as to surround the contact support portion. (Appendix 2) The contact support portion is a seal band formed in an annular shape along the peripheral edge portion of the first main surface. 2. The electrostatic chuck of claim 1. (Appendix 3) The groove portion is provided on the inner peripheral side of the seal band. 3. The electrostatic chuck of claim 2. (Appendix 4) The groove portion is provided on the outer circumferential side of the seal band. 4. The electrostatic chuck of claim 2 or 3. (Appendix 5) The contact support portion is a dot formed in a columnar shape. 5. The electrostatic chuck according to claim 1, wherein the electrostatic chuck is a chuck having a first end and a second end. (Appendix 6) The width of the groove is 5 μm or more and 150 μm or less. 6. An electrostatic chuck according to any one of claims 1 to 5. (Appendix 7) The depth of the groove is 10 μm or more and 100 μm or less. 6. An electrostatic chuck according to any one of claims 1 to 5. (Appendix 8) the electrostatic chuck has a plurality of the contact support portions, The groove portion is provided for each of the plurality of contact support portions. 8. An electrostatic chuck according to any one of claims 1 to 7. (Appendix 9) The groove portion is provided continuously so as to surround the contact support portion. 9. An electrostatic chuck according to any one of claims 1 to 8. (Appendix 10) The groove portions are provided discretely so as to surround the contact support portion. 9. An electrostatic chuck according to any one of claims 1 to 8. (Appendix 11) the electrostatic chuck has a flow path; The opening of the flow channel is formed in the first main surface. 11. An electrostatic chuck according to any one of claims 1 to 10. (Appendix 12) the contact support portion includes a first contact support portion formed in an annular shape along a peripheral edge portion of the first main surface, and a plurality of second contact support portions formed in a columnar shape in an inner region of the first contact support portion, The groove portion includes a first groove surrounding the first contact support portion and a plurality of second grooves provided for each of the plurality of second contact support portions. 2. The electrostatic chuck of claim 1. (Appendix 13) The groove is formed directly above the electrode. 13. The electrostatic chuck according to claim 1, wherein the electrostatic chuck is a (Appendix 14) a bottom surface of the groove is formed at a position closer to the electrode than the first main surface; 14. The electrostatic chuck of claim 13. (Appendix 15) An electrostatic chuck according to any one of Supplementary Note 1 to Supplementary Note 14, Substrate processing equipment.

[0063] The above describes the plasma processing apparatus 1, but the present disclosure is not limited to the above embodiments, etc., and various modifications and improvements are possible within the scope of the gist of the present disclosure described in the claims.

[0064] This application claims priority based on Japanese Patent Application No. 2022-144886, filed on September 12, 2022, the entire contents of which are incorporated herein by reference. [Explanation of symbols]

[0065] 1. Plasma processing equipment (substrate processing equipment) 11 Substrate support 14 Flow path 15 Heat transfer gas supply section 111 Main body 111a Central area 111b Annular Region 1110 Foundation 1111,1111C Electrostatic Chuck 1111a Ceramic components (dielectrics) 1111b Electrostatic electrode (electrode) 112 Ring Assembly 121 Excavation surface (first main surface) 122 dots (contact support part) 123 Seal band (contact support part) 124,125,126 Groove 141 Channel 142 Opening 200 charges

Claims

1. Dielectrics and The dielectric material comprises an electrode provided inside the dielectric, The dielectric is First main surface and, A columnar dot is formed that protrudes from the first main surface and contacts the back surface of the substrate to support the substrate, A seal band formed in an annular shape along the periphery of the first main surface, An opening provided on the first main surface for supplying heat transfer gas to the space between the substrate and the first main surface, The first main surface and the dot have a groove provided between them so as to surround the dot, Electrostatic chuck.

2. The width of the groove is 5 μm or more and 150 μm or less. The electrostatic chuck according to claim 1.

3. The depth of the groove is 10 μm or more and 100 μm or less. The electrostatic chuck according to claim 1.

4. The electrostatic chuck has a plurality of the dots, The groove portion is provided for each of the multiple dots. The electrostatic chuck according to claim 1.

5. Further comprising a second groove surrounding the seal band, The width of the second groove is at least 1.5 times wider than the width of the first groove. The electrostatic chuck according to claim 4.

6. The grooves are provided continuously so as to surround the dots. The electrostatic chuck according to claim 1.

7. The electrostatic chuck has a flow path, The opening of the flow channel is formed on the first main surface. The electrostatic chuck according to claim 1.

8. The groove portion is formed directly above the electrode. The electrostatic chuck according to claim 1.

9. The bottom surface of the groove is formed at a position closer to the electrode than the first main surface. The electrostatic chuck according to claim 8.

10. Between the dot and the groove, a parallel surface is provided. The electrostatic chuck according to claim 1.

11. The parallel surface is formed at the same height as the first main surface. The electrostatic chuck according to claim 10.

12. The area of ​​the parallel surface is smaller than the area of ​​the first main surface. The electrostatic chuck according to claim 11.

13. The charge leaked from the contact surface between the substrate and the dot is moved to the bottom surface of the groove by the adsorption voltage applied to the electrode and is accumulated on the bottom surface of the groove. The electrostatic chuck according to any one of claims 1 to 12.

14. A static chuck according to any one of claims 1 to 12, Circuit board processing equipment.

Images