Electrostatic chuck and substrate processing device

Abstract

The invention provides an electrostatic chuck capable of suppressing residual adsorption of a substrate and a substrate processing apparatus. The electrostatic chuck includes a dielectric body and an electrode provided inside the dielectric body. The dielectric body has: a first main surface; a contact support part protruding from the first main surface and supporting the substrate by being in contact with the back surface of the substrate; and a groove portion provided between the first main surface and the contact support portion so as to surround the contact support portion.

Description

Technical Field

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

[0002] Patent Document 1 discloses a holding device including a ceramic member having a concave portion and a plurality of convex portions (an outer peripheral seal ring and a columnar convex portion) formed on a suction surface.

[0003] Patent Document 2 discloses that electric charges remain on the surface of an electrostatic chuck, and a substrate is attracted by the residual charges.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent document 1: Japanese Patent Application Publication No. 2020-129632.

[0007] Patent Document 2: Japanese Patent Application Publication No. 2013-149935. Summary of the invention

[0008] Technical problem to be solved by the invention

[0009] In one aspect, the present invention provides an electrostatic chuck and a substrate processing apparatus that suppress residual adsorption of a substrate.

[0010] Technical means for solving technical problems

[0011] In order to solve the above-mentioned technical problems, according to one method, an electrostatic chuck is provided, which includes a dielectric and an electrode arranged inside the dielectric, wherein the dielectric has: a first main surface; a contact support portion, which protrudes more than the first main surface and contacts with the back side of a substrate to support the substrate; and a groove portion, which is arranged between the first main surface and the contact support portion in a manner surrounding the contact support portion.

[0012] Effects of the Invention

[0013] According to one aspect, it is possible to provide an electrostatic chuck and a substrate processing apparatus that suppress residual adsorption of a substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is an example of a diagram for explaining a configuration example of a capacitive coupling type plasma processing apparatus.

[0015] Figure 2 An example of a top view of an electrostatic chuck according to an embodiment.

[0016] Figure 3 This is an example of an AA cross-sectional view of an electrostatic chuck according to one embodiment.

[0017] Figure 4 This is an example of a top view of an electrostatic chuck of a reference example.

[0018] Figure 5 This is an example of a BB cross-sectional view of the electrostatic chuck of the reference example.

[0019] Figure 6 This is an example of a partially enlarged cross-sectional view showing a substrate holding state of an electrostatic chuck according to an embodiment.

[0020] Figure 7 This is an example of a partially enlarged cross-sectional view showing a substrate holding state of an electrostatic chuck according to a reference example.

[0021] Figure 8 Another example of a partially enlarged cross-sectional view showing a substrate holding state of the electrostatic chuck according to one embodiment. DETAILED DESCRIPTION

[0022] Hereinafter, the mode for implementing the present invention will be described with reference to the drawings. In each of the drawings, the same components are denoted by the same reference numerals and overlapping descriptions are omitted.

[0023] Hereinafter, a configuration example of a plasma processing system will be described. Figure 1 This is an example of a diagram for explaining a configuration example of a capacitive coupling type plasma processing apparatus (substrate processing apparatus) 1.

[0024] The plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a control unit 2. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. In addition, the plasma processing apparatus 1 includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit is configured to be able to introduce at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a showerhead 13. The substrate support unit 11 is disposed in the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support unit 11. In one embodiment, the showerhead 13 constitutes 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, the sidewall 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 has: at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s; and at least one gas exhaust port for exhausting gas from the plasma processing space. 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 .

[0025] The substrate support portion 11 includes a main body 111 and a ring assembly 112. The main body 111 has: a central area 111a for supporting a substrate W; and an annular area 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. The annular area 111b of the main body 111 surrounds the central area 111a of the main body 111 when viewed from above. The substrate W is arranged on the central area 111a of the main body 111, and the ring assembly 112 is arranged on the annular area 111b of the main body 111 in a manner of surrounding the substrate W on the central area 111a of the main body 111. Therefore, the central area 111a is also referred to as a substrate support surface for supporting the substrate W, and the annular area 111b is also referred to as a ring support surface for supporting the ring assembly 112.

[0026] In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive component. The conductive component of the base 1110 can function as a lower electrode (i.e., play a role). The electrostatic chuck 1111 is arranged on the base 1110. The electrostatic chuck 1111 includes a ceramic component 1111a and an electrostatic electrode 1111b arranged in the ceramic component 1111a. The ceramic component 1111a has a central area 111a. In one embodiment, the ceramic component 1111a also has an annular area 111b. In addition, other components surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck and an annular insulating component, may also have an annular area 111b. In this case, the ring assembly 112 can be arranged on the annular electrostatic chuck or the annular insulating component, or on both the electrostatic chuck 1111 and the annular insulating component. In addition, at least one RF / DC electrode coupled to the RF (Radio Frequency) power supply 31 and / or the DC (Direct Current) power supply 32 described later may also be arranged in the ceramic component 1111a. In this case, at least one RF / DC electrode functions as a lower electrode. In the case where the bias RF signal and / or DC signal described later is supplied to at least one RF / DC electrode, the RF / DC electrode is also referred to as a bias electrode. In addition, the conductive components of the base 1110 and at least one RF / DC electrode may also function as multiple lower electrodes. In addition, the electrostatic electrode 1111b may function as a lower electrode. Therefore, the substrate support portion 11 includes at least one lower electrode.

[0027] The ring assembly 112 includes one or more ring-shaped components. In one embodiment, the one or more ring-shaped components include one or more edge rings and at least one cover ring. The edge ring is formed of a conductive material or an insulating material, and the cover ring is formed of an insulating material.

[0028] In addition, the substrate support 11 may also include a temperature adjustment module, which is 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 in the flow path 1110a. In one embodiment, the flow path 1110a is formed in the base 1110, and one or more heaters are arranged in the ceramic component 1111a of the electrostatic chuck 1111. In addition, the substrate support 11 may also include a heat transfer gas supply unit 15, which is configured to supply heat transfer gas to the gap between the back side of the substrate W and the central area 111a. The heat transfer gas supply unit 15 supplies a heat transfer gas such as He gas between the back side of the substrate W placed on the electrostatic chuck 1111 and the first main surface (the lower excavated surface 121 described later) of the electrostatic chuck 1111 via the flow path 14.

[0029] The shower head 13 is configured to be able to introduce at least one processing gas from the gas supply part 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 a plurality of gas introduction ports 13c. The processing gas supplied to the gas supply port 13a is introduced into the plasma processing space 10s from the plurality of gas introduction ports 13c through the gas diffusion chamber 13b. In addition, the shower head 13 includes at least one upper electrode. In addition, in addition to the shower head 13, the gas introduction part may also include one or more side gas injection parts (SGI: Side Gas Injector) installed in one or more openings formed in the side wall 10a.

[0030] The gas supply unit 20 may also 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 processing gas from the corresponding gas source 21 to the shower head 13 via the corresponding flow controller 22. Each flow controller 22 may also include, for example, a mass flow controller or a pressure-controlled flow controller. In addition, the gas supply unit 20 may also include one or more flow modulation devices for modulating or pulsing the flow of at least one processing gas.

[0031] 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. Thus, plasma can be formed from at least one processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of a plasma generating unit configured to generate plasma from one or more processing gases in the plasma processing chamber 10. In addition, by supplying a bias RF signal to at least one lower electrode, a bias potential can be generated on the substrate W, and ion components in the formed plasma can be attracted to the substrate W.

[0032] In one embodiment, the RF power supply 31 includes a first RF generator 31a and a second RF generator 31b. The first RF generator 31a is configured to be coupled with at least one lower electrode and / or at least one upper electrode via at least one impedance matching circuit to generate a generation source RF signal (generation source RF electric power) for plasma generation. In one embodiment, the generation source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generator 31a may also be configured to generate a plurality of generation source RF signals having different frequencies. The generated one or more generation source RF signals are supplied to at least one lower electrode and / or at least one upper electrode.

[0033] The second RF generating unit 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 electric power (i.e., RF power)). The frequency of the bias RF signal may be the same as or different from the frequency of the generating source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the generating source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100kHz to 60MHz. In one embodiment, the second RF generating unit 31b may also be configured to generate a plurality of bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. In addition, in various embodiments, at least one of the generating source RF signal and the bias RF signal may also be pulsed.

[0034] In addition, 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 generating unit 32a and a second DC generating unit 32b. In one embodiment, the first DC generating unit 32a is connected to at least one lower electrode and is configured to generate a first DC signal. The generated first bias DC signal is applied to at least one lower electrode. In one embodiment, the second DC generating unit 32b is connected to at least one upper electrode and is configured to generate a second DC signal. The generated second DC signal is applied to at least one upper electrode.

[0035] In various embodiments, at least one of the first and second DC signals may also be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulse may have a pulse waveform of a rectangle, a trapezoid, a triangle, or a combination thereof. In one embodiment, a waveform generator for generating a sequence of voltage pulses according to a DC signal is connected between the first DC generator 32a and at least one lower electrode. Therefore, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. In the case where 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 pulse may have a positive polarity or a negative polarity. In addition, the sequence of voltage pulses may also include one or more positive polarity voltage pulses and one or more negative polarity voltage pulses in one cycle. In addition, in addition to the RF power supply 31, the first and second DC generators 32a, 32b may be provided, and the first DC generator 32a may also be provided in place of the second RF generator 31b.

[0036] The exhaust system 40 can be connected to the gas exhaust port 10e provided at the bottom of the plasma processing chamber 10, for example. The exhaust system 40 can also include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s can be adjusted by the pressure regulating valve. The vacuum pump can include a turbomolecular pump, a dry pump, or a combination thereof.

[0037] The control unit 2 processes computer executable commands that cause the plasma processing device 1 to perform various processes described in the present invention. The control unit 2 can be configured to control the various elements (constituent units) of the plasma processing device 1 to perform the various processes described herein. In one embodiment, a part or all of the control unit 2 can be included in the plasma processing device 1. The control unit 2 can include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The control unit 2 can be implemented by a computer 2a, for example. The processing unit 2a1 can be configured to perform various control actions by reading a program from the storage unit 2a2 and executing the read program. The program can be stored in the storage unit 2a2 in advance, or it can be obtained via a medium when necessary. The obtained program is stored in the storage unit 2a2, and is read and executed from the storage unit 2a2 by the processing unit 2a1. The medium can be various storage media readable by the computer 2a, or it can be a communication line connected to the communication interface 2a3. The processing unit 2a1 can be a CPU (Central Processing Unit). The storage 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 also communicate with the plasma processing device 1 via a communication line such as a LAN (Local Area Network).

[0038] Next, use Figure 2 and Figure 3 The electrostatic chuck 1111 is further described. Figure 2 An example of a top view of an electrostatic chuck 1111 according to one embodiment. Figure 3 An example of an AA cross-sectional view of the electrostatic chuck 1111 according to one embodiment.

[0039] The electrostatic chuck 1111 includes a ceramic component 1111a and an electrostatic electrode 1111b. The ceramic component 1111a is formed of a dielectric. The electrostatic electrode 1111b is disposed inside the ceramic component 1111a.

[0040] The electrostatic chuck 1111 has a hollowed surface (first main surface) 121 , a bump portion 122 , and a sealing ring 123 in the central region 111 a .

[0041] The undercut surface 121 is a surface that is undercut downward from the upper surface of the bump portion 122 (the mounting surface of the substrate W) and the upper surface of the seal ring 123 (the mounting surface of the substrate W). Figure 6 ) is a surface that is spaced apart from and faces the back surface of the substrate W. The surface of the undercut surface 121 is a processed surface that is subjected to sandblasting and grinding. The surface of the undercut surface 121 is, for example, a processed surface with an arithmetic mean roughness Ra of 0.1 (μm).

[0042] In addition, the electrostatic chuck 1111 has a flow path 141 and an opening 142. The flow path 141 is formed to penetrate the electrostatic chuck 1111 and pass through the flow path 14 (see Figure 1 ) from the heat transfer gas supply unit 15 (refer to Figure 1 The opening 142 is formed in the undercut surface 121.

[0043] A bump portion 122 and a seal ring 123 are formed in the central region 111 a of the electrostatic chuck 1111 and serve as a contact support portion that protrudes beyond the hollow surface 121 .

[0044] The bump portion 122 protrudes from the undercut surface 121 and is formed into a substantially cylindrical shape. Figure 2 ), a plurality of bump portions 122 are formed in the region inside the annular seal ring 123 formed at the peripheral portion of the central region 111a. The bump portions 122 are formed when the substrate W is placed on the electrostatic chuck 1111 (see the following description). Figure 6 ), the upper surface of the bump portion 122 contacts the back surface of the substrate W, supporting the inner area of ​​the substrate W. The upper surface of the bump portion 122 is a processed surface that has been subjected to a grinding process. The upper surface of the bump portion 122 is, for example, a processed surface with an arithmetic mean roughness Ra of 0.01 (μm).

[0045] The sealing ring 123 protrudes from the undercut surface 121 and is formed in a circular ring shape along the outer periphery of the central region 111a. The sealing ring 123 is provided when the substrate W is placed on the electrostatic chuck 1111 (see the following description). Figure 6 ), the upper surface of the sealing ring 123 contacts the back surface of the substrate W and supports the outer area of ​​the substrate W. The upper surface of the sealing ring 123 is a processed surface that has been subjected to a grinding process. The upper surface of the sealing ring 123 is, for example, a processed surface with an arithmetic mean roughness Ra of 0.01 (μm).

[0046] In addition, when the substrate W is placed on the electrostatic chuck 1111 (see the following description), Figure 6 ), the sealing ring 123 forms a space (gap) through the back side of the substrate W, the undercut surface 121 of the electrostatic chuck 1111, and the inner peripheral surface of the sealing ring 123. The heat transfer gas supplied from the heat transfer gas supply unit 15 is supplied to the space from the opening 142 formed in the undercut surface 121 via the flow path 14 and the flow path 141.

[0047] Grooves 124 and 125 are formed in the central region 111 a of the electrostatic chuck 1111 by being dug downward from the lower dug surface 121 .

[0048] The groove portion 124 is formed so as to surround the bump portion 122. In other words, the groove portion 124 is formed between the upper surface of the bump portion 122 and the undercut surface 121. In addition, the groove portion 124 is formed right above the electrostatic electrode 1111b.

[0049] The groove 125 is formed so as to surround (enclose) the inner circumference of the seal ring 123. In other words, the groove 124 is formed between the upper surface of the bump portion 122 and the undercut surface 121. The groove 125 is formed just above the electrostatic electrode 1111b.

[0050] In addition, the electrostatic suction cup 1111 has a plurality of contact support portions (bump portions 122, sealing rings 123), and the groove portions 124, 125 are provided corresponding to each of the plurality of contact support portions (bump portions 122, sealing rings 123). In addition, the plurality of groove portions 124, 125 are provided continuously in a manner surrounding the contact support portion. However, the groove portions 124, 125 may also be provided discretely. In other words, it may also be provided so that a plurality of groove portions 124, 125 surround one contact support portion 122, 123.

[0051] In addition, the bottom surfaces of the grooves 124 and 125 are formed at positions closer to the electrostatic electrode 1111b than the lower cut surface 121. In addition, the bottom surfaces of the grooves 124 and 125 are formed at positions closer to the electrostatic electrode 1111b than the contact surface for mounting the substrate W (the upper surface of the bump portion 122 and the upper surface of the sealing ring 123). In addition, the lower cut surface 121 is formed at a position closer to the electrostatic electrode 1111b than the contact surface for mounting the substrate W (the upper surface of the bump portion 122 and the upper surface of the sealing ring 123).

[0052] The width of the grooves 124 and 125 is preferably, for example, 5 μm or more and 150 μm or less. By forming the width of the grooves 124 and 125 to be 150 μm or less, it is possible to ensure that the area of ​​the undercut surface 121 that acts on the adsorption force when the substrate W is electrostatically adsorbed is large. In addition, by forming the width of the grooves 124 and 125 to be 5 μm or more, the grooves 124 and 125 can be easily formed. In addition, the grooves 124 and 125 are formed by, for example, grooving processing using a laser.

[0053] In addition, when looking down (see Figure 2 ), the area of ​​the grooves 124 and 125 is preferably less than 10% of the area of ​​the lower excavated surface 121.

[0054] In addition, it is preferable that the width of the groove portion 125 is wider than the width of the groove portion 124. Specifically, it is preferable that the width of the groove portion 125 is wider than the width of the groove portion 124 by 1.5 times or more.

[0055] The depth of the grooves 124 and 125 is preferably at least twice the roughness of the undercut surface 121. In addition, the depth of the grooves 124 and 125 is preferably, for example, not less than 10 μm and not more than 100 μm.

[0056] Next, use Figure 4 and Figure 5 , the electrostatic chuck 1111C of the reference example is described. Figure 4 This is an example of a top view of an electrostatic chuck 1111C of a reference example. Figure 5 This is an example of a BB cross-sectional view of an electrostatic chuck 1111C of a reference example.

[0057] The central region 111a of the electrostatic chuck 1111C of the reference example has a hollow surface 121, a bump portion 122, and a seal ring 123. That is, the difference is that the grooves 124 and 125 are not formed. The other structures are the same, and repeated descriptions are omitted.

[0058] Next, the electrostatic chuck 1111 according to one embodiment will be further described in comparison with the electrostatic chuck 1111C of the reference example. Figure 6 This is an example of a partially enlarged cross-sectional view showing a substrate holding state of the electrostatic chuck 1111 according to one embodiment. Figure 7 This is an example of a partially enlarged cross-sectional view showing the substrate holding state of the electrostatic chuck 1111 of the reference example.

[0059] When adsorbing the substrate W, an adsorption voltage (e.g., 2.5 kV) is applied to the electrostatic electrode 1111b to induce charges in the substrate W. The Coulomb force is generated due to the potential difference between the induced charges of the substrate W and the electrostatic electrode 1111b, and the substrate W is electrostatically adsorbed to the electrostatic chuck 1111 (1111C). In addition, the adsorption is released by stopping the application of the adsorption voltage to the electrostatic electrode 1111b.

[0060] Here, a film of reaction byproducts may be formed on the surface of the electrostatic chuck 1111 (1111C) when the substrate W is processed. If the insulation of the reaction byproduct film is low, in a high temperature process or a long time process, Figure 6 and Figure 7 As shown by the arrow, the charge 200 leaks from the contact surface on which the substrate W is mounted (the upper surface of the bump portion 122 and the upper surface of the sealing ring 123), and the charge 200 moves downward due to the adsorption voltage applied to the electrostatic electrode 1111b and the self-bias of the plasma.

[0061] exist Figure 7In the electrostatic suction cup 1111C shown, the charge 200 leaked from the contact surface on which the substrate W is carried (the upper surface of the bump portion 122, the upper surface of the sealing ring 123) moves toward the lower hollow surface 121 that is not in contact with the substrate W due to the adsorption voltage applied to the electrostatic electrode 1111b, and the charge 200 is accumulated on the lower hollow surface 121.

[0062] Thus, the Coulomb force is generated by the charge of the substrate W and the charge 200 accumulated in the undercut surface 121, and even if the application of the adsorption voltage to the electrostatic electrode 1111b is stopped, the electrostatic adsorption between the substrate W and the electrostatic chuck 1111C may be maintained (residual adsorption occurs). On the other hand, in order to reduce the charge leaked from the substrate W to the contact support part, it is considered to reduce the contact area between the contact support part (the bump part 122 and the sealing ring 123) and the substrate W, but there is a problem that the adsorption force on the substrate W and the sealing performance of the heat transfer gas are reduced.

[0063] In addition, since the adsorption voltage is continuously applied to the electrostatic electrode 1111b, the charge 200 accumulated in the undercut surface 121 increases, so that the Coulomb force between the substrate W and the electrostatic chuck 1111C decreases. Therefore, even when the adsorption voltage is applied to the electrostatic electrode 1111b, the substrate W may fall off from the electrostatic chuck 1111C due to the pressure of the heat transfer gas.

[0064] And in Figure 6 In the electrostatic chuck 1111 shown, the charge 200 leaked from the contact surface (the upper surface of the bump portion 122 and the upper surface of the seal ring 123) on which the substrate W is placed moves to the bottom surface of the groove portions 124 and 125 due to the adsorption voltage applied to the electrostatic electrode 1111b, and the charge 200 is accumulated on the bottom surface of the groove portions 124 and 125. In addition, the lower cut surface 121 is formed at a position (higher position) farther from the electrostatic electrode 1111b than the bottom surface of the groove portions 124 and 125 when viewed from the electrostatic electrode 1111b. Therefore, the charge 200 moved to the bottom surface of the groove portions 124 and 125 does not move to the lower cut surface 121 due to the adsorption voltage applied to the electrostatic electrode 1111b.

[0065] Here, the Coulomb force is proportional to the area of ​​the surface of the charge accumulation 200, and inversely proportional to the distance between the back surface of the substrate W and the surface of the charge accumulation 200. The surface of the electrostatic chuck 1111 that accumulates the charge 200 is the bottom surface of the grooves 124 and 125. In addition, the accumulation surface of the electrostatic chuck 1111C is the down-cut surface 121. Therefore, the electrostatic chuck 1111 can reduce the area of ​​the surface of the charge accumulation 200 and reduce the Coulomb force. In addition, the electrostatic chuck 1111 can increase the distance between the back surface of the substrate W and the surface of the charge accumulation 200 and reduce the Coulomb force. As a result, the residual adsorption force can be reduced.

[0066] For example, when the area of ​​the grooves 124 and 125 is 10% of the area of ​​the lower excavated surface 121 and the width of the grooves 124 and 125 is 70 μm, the residual adsorption force is approximately 1 / 40 when the depth of the grooves 124 and 125 (the distance from the lower excavated surface 121 to the bottom surfaces of the grooves 124 and 125) is 10 to 20 μm, the residual adsorption force is approximately 1 / 45 when the depth of the grooves 124 and 125 is 20 to 50 μm, and the residual adsorption force is approximately 1 / 50 when the depth of the grooves 124 and 125 is 50 to 100 μm. In addition, when the width of the grooves 124 and 125 is 700 μm and the depth of the grooves 124 and 125 is 10 to 20 μm, the residual adsorption force is approximately 1 / 100; when the depth of the grooves 124 and 125 is 20 to 50 μm, the residual adsorption force is approximately 1 / 110; and when the depth of the grooves 124 and 125 is 50 to 100 μm, the residual adsorption force is approximately 1 / 150.

[0067] In addition, even when the adsorption voltage is continuously applied to the electrostatic electrode 1111b, the charges 200 are accumulated on the bottom surfaces of the grooves 124 and 125, the charges 200 are not accumulated on the cut surface 121, and the substrate W can be electrostatically adsorbed by the cut surface 121. Thus, in the state where the adsorption voltage is applied to the electrostatic electrode 1111b, the substrate W can be suppressed from falling off the electrostatic chuck 1111C. Thus, the pressure of the heat transfer gas can be ensured, and thus the cooling performance of the substrate W can be ensured. In addition, the width of the sealing ring 123 can be ensured, and the sealing performance of the heat transfer gas can be ensured.

[0068] In addition, when releasing the adsorption of the substrate W, a voltage (e.g. -500 V) opposite to the adsorption voltage is applied to the electrostatic electrode 1111b to reduce the residual adsorption force. Figure 6 In the electrostatic chuck 1111 shown, the charges 200 are accumulated on the bottom surfaces of the small grooves 124 and 125, and the charge density becomes high. In addition, the grooves 124 and 125 are provided directly above the electrostatic electrode 1111b. Therefore, the removal efficiency of the charges 200 can be improved when the residual adsorption force is reduced.

[0069] In addition, the width of the groove portion 125 is preferably wider (larger) than the width of the groove portion 124 . Thus, the charge leaked from the seal ring 123 having a large contact area with the substrate W can be accumulated in the groove portion 125 .

[0070] In the above, the embodiment in which the grooves 124 and 125 are provided in the electrostatic chuck 1111 has been described, but the present invention is not limited to this.

[0071] It is also possible to form only the groove portion 125 surrounding the inner circumference of the sealing ring 123, and omit the groove portion 124 surrounding the bump portion 122. For example, when the number of the bump portions 122 is small, in other words, when the sum of the areas of the upper surfaces of the plurality of bump portions 122 in contact with the substrate W is sufficiently smaller than the area of ​​the upper surface of the sealing ring 123 in contact with the substrate W, the charge leaked from the upper surface of the bump portion 122 is smaller than the charge leaked from the upper surface of the sealing ring 123. In such a structure, it is also possible to form only the groove portion 125 surrounding the inner circumference of the sealing ring 123.

[0072] In addition, a parallel surface may be provided in the middle from the contact surface on which the substrate W is placed (the upper surface of the bump portion 122, the upper surface of the sealing ring 123) to the bottom surface of the groove portions 124 and 125. The parallel surface may be formed to be the same height as the lower cut surface 121. The area of ​​the parallel surface is formed to be smaller than the area of ​​the lower cut surface 121. In such a structure, the charge 200 leaked from the contact surface on which the substrate W is placed (the upper surface of the bump portion 122, the upper surface of the sealing ring 123) moves to the parallel surface due to the adsorption voltage applied to the electrostatic electrode 1111b, and then moves to the bottom surface of the groove portions 124 and 125, and the charge 200 is accumulated on the bottom surface of the groove portions 124 and 125.

[0073] In addition, although the structure in which the groove portion 125 is formed so as to surround the inner peripheral side of the seal ring 123 has been described, the present invention is not limited to this. Figure 8 FIG. 1 is another example of a partially enlarged cross-sectional view showing a substrate holding state of the electrostatic chuck 1111 according to an embodiment. Figure 8 As shown, the groove portion 126 may be formed so as to surround the outer circumference of the seal ring 123 .

[0074] In addition, the structure in which the electrostatic chuck 1111 uses the Coulomb force to adsorb the substrate W is described as an example, but it is not limited to this, and it can also be applied to a structure that uses the Johnson-Rahbek effect to adsorb the substrate W. In addition, the structure in which the electrostatic electrode 1111b of the electrostatic chuck 1111 is a monopole is described as an example, but it is not limited to this, and it can also be a multipolar structure, and it can be a monopolar structure or a bipolar structure.

[0075] The above-described embodiments include the following aspects, for example.

[0076] (Note 1)

[0077] An electrostatic chuck, comprising:

[0078] Dielectric; and

[0079] an electrode disposed inside the dielectric,

[0080] The dielectric has:

[0081] first main surface;

[0082] a contact support portion, which protrudes from the first main surface and contacts with the back surface of the substrate to support the substrate; and

[0083] A groove portion is provided between the first main surface and the contact support portion so as to surround the contact support portion.

[0084] (Note 2)

[0085] The electrostatic chuck according to Supplement 1, wherein:

[0086] The contact support portion is a seal ring formed in an annular shape along a peripheral edge portion of the first main surface.

[0087] (Note 3)

[0088] The electrostatic chuck according to Supplement 2, wherein:

[0089] The groove portion is provided on the inner circumference side of the seal ring.

[0090] (Note 4)

[0091] The electrostatic chuck according to Supplement 2 or 3, wherein:

[0092] The groove portion is provided on the outer peripheral side of the seal ring.

[0093] (Note 5)

[0094] An electrostatic chuck according to any one of Supplementary Notes 1 to 4, wherein

[0095] The contact support portion is a convex point portion formed in a columnar shape.

[0096] (Note 6)

[0097] An electrostatic chuck according to any one of Supplementary Notes 1 to 5, wherein

[0098] The groove has a width of 5 μm or more and 150 μm or less.

[0099] (Note 7)

[0100] An electrostatic chuck according to any one of Supplementary Notes 1 to 5, wherein

[0101] The depth of the groove is not less than 10 μm and not more than 100 μm.

[0102] (Note 8)

[0103] An electrostatic chuck according to any one of Supplementary Notes 1 to 7, wherein

[0104] The electrostatic chuck has a plurality of contact support portions.

[0105] The groove portion is provided for each of the plurality of contact support portions.

[0106] (Note 9)

[0107] An electrostatic chuck according to any one of Supplementary Notes 1 to 8, wherein

[0108] The groove portion is continuously provided so as to surround the contact support portion.

[0109] (Note 10)

[0110] An electrostatic chuck according to any one of Supplementary Notes 1 to 8, wherein

[0111] The groove portions are discretely provided so as to surround the contact support portion.

[0112] (Note 11)

[0113] An electrostatic chuck according to any one of Supplementary Notes 1 to 10, wherein

[0114] The electrostatic chuck has a flow path,

[0115] An opening of the flow path is formed on the first main surface.

[0116] (Note 12)

[0117] The electrostatic chuck according to Supplement 1, wherein:

[0118] The contact support portion includes: a first contact support portion formed in an annular shape along the peripheral edge 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.

[0119] 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.

[0120] (Note 13)

[0121] An electrostatic chuck according to any one of Supplementary Notes 1 to 12, wherein

[0122] The groove portion is formed directly above the electrode.

[0123] (Note 14)

[0124] The electrostatic chuck according to Supplementary Note 13, wherein

[0125] The bottom surface of the groove portion is formed at a position closer to the electrode than the first main surface.

[0126] (Note 15)

[0127] A substrate processing device comprises an electrostatic chuck as described in any one of Notes 1 to 14.

[0128] As mentioned above, the plasma processing apparatus 1 has been described, but the present invention is not limited to the above-mentioned embodiment and the like, and various modifications and improvements can be made within the scope of the gist of the present invention described in the claims.

[0129] In addition, the present 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.

[0130] Description of Reference Numerals

[0131] 1Plasma processing device (substrate processing device)

[0132] 11 substrate support part

[0133] 14 flow paths

[0134] 15Heat transfer gas supply unit

[0135] 111 Main body

[0136] 111a Central Area

[0137] 111b ring region

[0138] 1110 base

[0139] 1111, 1111C electrostatic chuck

[0140] 1111a Ceramic components (dielectric)

[0141] 1111b Electrostatic electrode (electrode)

[0142] 112 ring assembly

[0143] 121 lower excavation surface (first main surface)

[0144] 122 bump portion (contact support portion)

[0145] 123 Sealing ring (contact support part)

[0146] 124, 125, 126 slots

[0147] 141 flow path

[0148] 142 opening

[0149] 200 charges.

Claims

1. An electrostatic chuck, characterized in that: include: Dielectrics; and An electrode is disposed inside the dielectric, The dielectric has: first main surface; a contact support portion, which protrudes from the first main surface and contacts with the back surface of the substrate to support the substrate; and A groove portion is provided between the first main surface and the contact support portion so as to surround the contact support portion.

2. The electrostatic chuck according to claim 1, characterized in that: The contact support portion is a seal ring formed in an annular shape along a peripheral edge portion of the first main surface.

3. The electrostatic chuck according to claim 2, characterized in that: The groove portion is provided on the inner circumference side of the seal ring.

4. The electrostatic chuck according to claim 3, characterized in that: The groove portion is provided on the outer peripheral side of the seal ring.

5. The electrostatic chuck according to claim 1, characterized in that: The contact support portion is a convex point portion formed in a columnar shape.

6. The electrostatic chuck according to any one of claims 1 to 5, characterized in that: The groove has a width of 5 μm or more and 150 μm or less.

7. The electrostatic chuck according to any one of claims 1 to 5, characterized in that: The depth of the groove is not less than 10 μm and not more than 100 μm.

8. The electrostatic chuck according to any one of claims 1 to 5, characterized in that: The electrostatic chuck has a plurality of contact support portions. The groove portion is provided for each of the plurality of contact support portions.

9. The electrostatic chuck according to any one of claims 1 to 5, characterized in that: The groove portion is continuously provided so as to surround the contact support portion.

10. The electrostatic chuck according to any one of claims 1 to 5, characterized in that: The groove portions are discretely provided so as to surround the contact support portion.

11. The electrostatic chuck according to any one of claims 1 to 5, characterized in that: The electrostatic chuck has a flow path, An opening of the flow path is formed on the first main surface.

12. The electrostatic chuck according to claim 1, wherein: The contact support portion includes: a first contact support portion formed in an annular shape along the peripheral edge 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.

13. The electrostatic chuck according to any one of claims 1 to 5, characterized in that: The groove portion is formed directly above the electrode.

14. The electrostatic chuck according to claim 13, wherein: The bottom surface of the groove portion is formed at a position closer to the electrode than the first main surface.

15. A substrate processing device, characterized in that: An electrostatic chuck comprising the electrostatic chuck according to any one of claims 1 to 5.

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