Apparatus for radio frequency power application

Abstract

The embodiments described herein relate to apparatus and methods for substantially reducing the occurrence of radio frequency (RF) coupling via clamping electrodes. The clamping electrodes are disposed in an electrostatic chuck placed on a substrate support. The substrate support is coupled to a processing chamber body. An RF source is used to generate plasma in a processing volume adjacent to the substrate support. An impedance matching circuit is disposed between the RF source and the clamping electrodes disposed in the electrostatic chuck. An electrostatic chuck filter is coupled between the clamping electrodes and the clamping power source.

Description

Technical Field

[0001] Embodiments of the present disclosure relate generally to semiconductor processing and, more particularly, to apparatus and methods for generating and controlling radio frequency plasma for thin film deposition. Prior Art

[0002] In the fabrication of integrated circuits, deposition processes, such as chemical vapor deposition (CVD), are commonly used to deposit films of various materials on substrates. For example, in plasma-enhanced chemical vapor deposition (PECVD), electromagnetic energy is applied to at least one precursor gas or vapor to generate a plasma.

[0003] In some examples, the electromagnetic energy used to generate the plasma can be radio frequency (RF) power. However, when using RF power, capacitive coupling occurs between the plasma and the clamping electrode in the electrostatic chuck. This capacitive coupling results in RF coupling, which induces high RF voltages and currents on and through the clamping electrode, leading to power loss and damage to the clamping electrode's power supply.

[0004] Accordingly, there is a need for improved apparatus and methods for RF power application. Summary of the Invention

[0005] In one embodiment, an apparatus is provided that includes a chamber body and a lid, the chamber body and the lid defining a processing volume within the chamber body and the lid. A substrate support is disposed within the processing volume. A first electrode is embedded in the substrate support. A radio frequency (RF) source is coupled to the first electrode. An impedance matching circuit is disposed between the RF source and the first electrode. A second electrode is embedded in the substrate support. A power source is coupled to the second electrode. An electrode filter is disposed between and coupled to the second electrode and the power source.

[0006] In another embodiment, an apparatus is provided that includes a chamber body and a lid, the chamber body and the lid defining a processing volume within the chamber body and the lid. A gas distribution plate is disposed in the processing volume and positioned adjacent to the lid. A substrate support is disposed in the processing volume. A first electrode is embedded in the substrate support. A radio frequency (RF) source is coupled to the first electrode. An impedance matching circuit is disposed between the RF source and the electrode. A second electrode is embedded in the substrate support. A power source is coupled to the second electrode. An electrode filter is disposed between the second electrode and the power source. The electrode filter includes: a first inductor coupled to the second electrode; a second inductor connected in series with the first inductor; a third inductor connected in series with the first inductor and the second inductor; a resistor connected in series with the first inductor, the second inductor, and the third inductor; the resistor coupled to the power source; and a first capacitor connected in parallel with the second inductor.

[0007] In another embodiment, an apparatus is provided that includes a chamber body and a lid, the chamber body and the lid defining a processing volume within the chamber body and the lid. A gas distribution plate is disposed in the processing volume and positioned adjacent to the lid. A substrate support is disposed in the processing volume. A first electrode is embedded in the substrate support. A second electrode is embedded in the substrate support between the first electrode and a surface of the substrate support facing the lid. A radio frequency (RF) source is coupled to the first electrode. An impedance matching circuit is disposed between the RF source and the first electrode. A power source is coupled to the second electrode. An electrode filter is disposed between the second electrode and the power source. The electrode filter includes: a first inductor coupled to the second electrode; a second inductor connected in series with the first inductor; a third inductor connected in series with the first and second inductors; and a resistor connected in series with the first, second, and third inductors. The resistor is coupled to the power source. The electrode filter also includes: a first capacitor connected in parallel with the second inductor; a first ground path coupled to the electrode filter between the second inductor and the third inductor; and a second ground path coupled to the electrode filter between the third inductor and the resistor. The first ground path includes a second capacitor. The second ground path includes a third capacitor. Simple diagram description

[0008] In order to understand in detail the manner in which the above-mentioned features of the present disclosure are achieved, a more particular description of the present disclosure may be given by reference to the embodiments, the description of which is briefly summarized above, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, as the present disclosure may admit to other equally effective embodiments.

[0009] FIG. 1 is a schematic diagram of a processing chamber according to one embodiment.

[0010] 2A is a schematic representation of a filter circuit according to one embodiment.

[0011] 2B is a schematic representation of a filter circuit according to one embodiment.

[0012] 3 is a schematic representation of an impedance matching circuit according to one embodiment.

[0013] 4 is a plan view of a cluster tool apparatus according to one embodiment described herein.

[0014] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation. Implementation Method

[0015] Embodiments described herein relate to apparatus and methods for substantially reducing the occurrence of radio frequency (RF) coupling through a chucking electrode. The chucking electrode is disposed in a substrate support coupled to a processing chamber body. An RF source is used to generate a plasma in a processing volume adjacent to the substrate support. An impedance matching circuit is disposed between the RF source and the chucking electrode disposed in the substrate support. To reduce damage to the chucking electrode and a chucking power source coupled thereto, an electrostatic chuck filter is coupled between the chucking electrode and the chucking power source.

[0016] FIG1 is a schematic diagram of a processing chamber 100 according to one embodiment. The processing chamber 100 includes a chamber body 102 and a lid 104, which define a processing volume 120 within the chamber body 102 and the lid 104. A substrate support 114 and a gas distribution plate 108 are disposed within the processing volume 120. The substrate support 114 is supported within the chamber body 102 via rods 106. The substrate support 114 includes one or more conductive plates, insulating plates, equipment plates, cooling channels, etc. to facilitate processing of substrates. In one embodiment, the rods 106 are substantially orthogonal to the lid 104 and are coupled to the chamber body 102 relative to the lid 104 or disposed through openings in the chamber body 102 relative to the lid.

[0017] In one embodiment that may be combined with one or more of the above embodiments, the substrate support 114 is made of an aluminum-containing material. For example, the substrate support 114 may be made of aluminum nitride. An electrostatic chuck 115 may be placed on the upper surface of the substrate support 114 to facilitate chuck of the substrate during processing. The electrostatic chuck 115 includes an electrode 122 disposed therein. In one embodiment that may be combined with one or more of the above embodiments, the electrode 122 is a conductive mesh.

[0018] The upper surface 116 of the electrostatic chuck 115 may have a plurality of raised portions (not shown) formed thereon. The raised portions may contact a substrate (not shown) disposed on the upper surface 116 of the electrostatic chuck 115. Gas may flow between the substrate and the surface 116 of the electrostatic chuck 115 and / or between the substrate support 114 and the lower surface of the electrostatic chuck to maintain a thermal balance between the substrate and the substrate support 114. In such an example, the fluid temperature may be controlled, for example, via a heat exchanger.

[0019] A gas distribution plate 108 is coupled to the chamber body 102. A plenum 110 is defined between the lid 104 and the gas distribution plate 108. The gas distribution plate 108 is disposed opposite a substrate support 114. A plurality of apertures 112 are formed through the gas distribution plate 108. The plurality of apertures 112 are distributed across the gas distribution plate 108 to facilitate the flow of process gases into the processing volume 120.

[0020] A gas delivery system 126 is coupled to the lid 104 via a delivery line 128. The gas delivery system 126 provides one or more gases to the processing chamber 100 for processing a substrate disposed therein. When the one or more gases enter the processing chamber 100 through the lid 104, the gases enter the plenum 110 and flow through a plurality of holes 112 in the gas distribution plate 108. The plurality of holes 112 distribute the gases radially across a surface 116 of the electrostatic chuck 115.

[0021] Electrode 118 is embedded in substrate support 114. Radio frequency (RF) power is provided to electrode 118 via RF source 134. RF source 134 is coupled to electrode 118 via impedance matching circuit 136. RF source 134 is capable of providing RF power to electrode 118 at one or more frequencies simultaneously. For example, RF source 134 provides RF power to electrode 118 at a frequency of approximately 13.56 MHz and a frequency of approximately 40 MHz. To this end, RF source 134 includes frequency generators 138A and 138B for each frequency. While two frequency generators 138A and 138B are shown, RF source 134 may include any number of frequency generators for each frequency used. The characteristic impedance of RF source 134 is approximately 50 ohms.

[0022] The impedance matching circuit 136 is capable of striking and maintaining the plasma in the processing volume 120. The impedance matching circuit 136 combines the RF signals of various frequencies from the RF source 134. The impedance matching circuit 136 transmits the combined RF signal to the electrode 118 embedded in the substrate support 114. The combined RF signal is transmitted to the process gas in the processing volume 120 to generate a capacitively coupled plasma therein. The chamber body 102 is coupled to ground and provides an RF return path to facilitate the generation of the capacitively coupled plasma.

[0023] In one embodiment, the RF power supplied to electrode 118 is between about 5 kW and about 15 kW, for example, between about 8 kW and about 13 kW, or about 10 kW. The RF current supplied to electrode 118 is between about 120 amps and about 80 amps, for example, about 110 amps. This high RF current is achieved by the relatively low resistance of impedance matching circuit 136, which is between about 0.2 ohms and about 0.4 ohms. The voltage delivered to electrode 118 is between about 8 kV and about 13 kV, for example, about 10 kV. The impedance angle of impedance matching circuit 136 is between about 85 degrees and about 90 degrees, for example, between about 87 degrees and about 89 degrees.

[0024] The electrode 122 is a component of the electrostatic chuck 115 disposed on the substrate support 114. A dielectric layer (not shown) may be disposed on the electrostatic chuck 115 and form the surface 116 of the electrostatic chuck 115. A power supply 132 is coupled to the electrode 122 and provides sufficient power to the electrode 122 to generate an electrostatic force to hold the substrate on the surface 116 of the electrostatic chuck 115. In one embodiment, which may be combined with one or more of the above embodiments, the power supply 132 provides direct current (DC) power to the electrode 122.

[0025] The coupling capacitance of electrode 122 is between about 800 pF and about 2500 pF. In one embodiment that may be combined with one or more of the above embodiments, electrode 122 is made of a material containing aluminum. In one embodiment that may be combined with one or more of the above embodiments, electrode 122 is disposed between electrode 118 and surface 116 of electrostatic chuck 115.

[0026] When plasma is generated in the processing volume 120, RF current enters the electrode 122 and flows toward the power supply 132 (e.g., RF leakage). RF current entering and flowing through the power supply 132 can damage the power supply 132, which can result in power loss at the electrode and loss of clamping force applied to a substrate disposed thereon. To prevent damage to the power supply 132, a filter circuit 130 is positioned between the power supply 132 and the electrode 122.

[0027] The filter circuit 130 (e.g., an RF filter) substantially prevents RF current from flowing toward the power source 132. Thus, the filter circuit 130 substantially reduces the risk of damage to the power source 132 by redirecting the RF current (e.g., to ground). The input impedance of the filter circuit 130 is sufficiently high relative to ground to minimize current transfer from the substrate and plasma. However, the impedance of the filter circuit 130 is sufficiently low to substantially prevent current from flowing toward the power source 132.

[0028] A controller 124 is coupled to the processing chamber 100 to control various aspects of the processes performed therein. For example, the controller 124 controls the flow rate of process gases from the gas delivery system 126 to the processing volume 120. The controller 124 may also control the loading and unloading of substrates from the processing chamber 100. Furthermore, the controller 124 may control aspects of the impedance matching circuit 136 and the filter circuit 130, such as the capacitance of the variable capacitor.

[0029] FIG2A is a schematic representation of a filter circuit 200 according to one embodiment. Filter circuit 200 may correspond to filter circuit 130 described above with respect to FIG1 . Filter circuit 200 includes a first inductor 202 coupled to an electrode (e.g., electrode 122 illustrated in FIG1 ). A second inductor 206 is connected in series with first inductor 202. A third inductor 210 is connected in series with first inductor 202 and second inductor 206. A resistor 214 is connected in series with first inductor 202, second inductor 206, and third inductor 210. Resistor 214 is coupled to a power source, such as power supply 132 illustrated in FIG1 .

[0030] A first capacitor 204 is provided in parallel with a second inductor 206. The first capacitor 204 and the second inductor 206 form an LC resonant circuit. A first ground path includes a second capacitor 208, which is coupled to the filter circuit 200 between the second inductor 206 and the third inductor 210 and is also coupled to ground. A second ground path includes a third capacitor 212, which is coupled to the filter circuit 200 between the third inductor 210 and the resistor 214 and is also coupled to ground. The second capacitor 208 and the third capacitor 212 are shunt capacitors coupled to ground.

[0031] The first portion 231 of the filter circuit includes the first inductor 202, the second inductor 206, and the first capacitor 204. The first portion 231 is the inductive portion of the filter circuit 200. Most of the RF current entering the filter circuit 200 at 13.56 MHz is removed by the first inductor 202. Similarly, most of the RF current at 40 MHz is removed by the LC resonant circuit including the second inductor 206 and the first capacitor 204.

[0032] The second portion 233 of the filter circuit 200 is a low-pass filter comprising a second capacitor 208, a third inductor 210, and a third capacitor 212. Resistor 214 is an optional current-limiting resistor between the second portion 233 and the power supply. The second portion 233 removes any remaining RF current from the filter circuit 200 to prevent RF current from leaking into the power supply connected to resistor 214.

[0033] The values of the components of the filter circuit 200 (e.g., the first inductor 202, the second inductor 206, the third inductor 210, the first capacitor 204, the second capacitor 208, the third capacitor 212, and the resistor 214) can be tuned based on one or more frequencies of the RF current flowing therethrough. For example, in one embodiment that can be combined with one or more of the above embodiments, the first inductor 202 has an inductance of about 14 μH to about 25 μH, such as about 20 μH, the third inductor 210 has an inductance of about 8 μH to about 13 μH, such as about 10 μH, the second capacitor 208 and the third capacitor 212 have an inductance of about 800 pF to about 15,000 pF, such as about 1,000 pF, and the resistor has a resistance of about 1 Ω to about 5 Ω, such as about 2 Ω.

[0034] The LC resonant circuit (including first capacitor 204 and second inductor 206) may have a resonant frequency of 40 MHz. The values of the components in first portion 231 (e.g., first inductor 202, second inductor 206, and first capacitor 204) may be based on an input frequency of 13.56 MHz. In other words, first portion 231 may be designed to remove RF current at a frequency of 13.56 MHz.

[0035] Advantageously, the filter circuit 200 illustrated in Figure 2A substantially reduces the RF current flowing from the electrode 122 illustrated in Figure 1 to the power supply 132. Thus, the filter circuit 200 substantially reduces the extent and incidence of damage to the power supply.

[0036] FIG2B is a schematic representation of a filter circuit 270 according to one embodiment. Filter circuit 270 may correspond to filter circuit 130 described above with respect to FIG1 . That is, filter circuit 270 may be an alternative design to filter circuit 200 described above with respect to FIG2A .

[0037] Filter circuit 270 includes a first portion 260 and a second portion 262. First portion 260 includes a first inductor group 230 and a second inductor group 232 connected in series. Second portion 262 includes a capacitor group 234, a third inductor group 236, and a shunt capacitor 254. Capacitor group 234 and shunt capacitor 254 are connected in parallel. As shown, first inductor group 230 includes four inductors 240a, 240b, 240c, and 240d connected in parallel. Second inductor group 232 includes four inductors 242a, 242b, 242c, and 242d connected in parallel. First portion 260 of filter circuit 270 has a combined inductance of 20 μH.

[0038] As shown, second portion 262 of filter circuit 270 is a low-pass filter. Capacitor bank 234 includes four capacitors 246, 248, 250, and 252. A third inductor bank includes three inductors 244a, 244b, and 244c connected in parallel. Each capacitor 246, 248, 250, 252, and 254 has a capacitance of 1000 pF. The inductance of third inductor bank 236 is approximately 10 μH. The values of the components of filter circuit 270 can be tuned based on one or more input frequencies to be removed by filter circuit 270.

[0039] FIG3 is a schematic representation of an impedance matching circuit 300 according to one embodiment. Impedance matching circuit 300 includes a first variable capacitor 306 and an inductor 308 connected in series. A second variable capacitor 304 is coupled to impedance matching circuit 300 upstream of first variable capacitor 306 and grounded. Impedance matching circuit 300 provides input impedance to a plasma formed in a processing chamber, such as processing chamber 100 described above with respect to FIG1 .

[0040] FIG4 is a plan view of a cluster tool apparatus 400 according to one embodiment described herein. The apparatus 400 includes a plurality of process chambers 402, 404, 406, and 408, a transfer chamber 420, and load lock chambers 410 and 412. Each of the process chambers 402, 404, 406, and 408 is coupled to the transfer chamber 420. Although four process chambers 402, 404, 406, and 408 are shown in FIG4 , any number of process chambers may be coupled to the transfer chamber 420.

[0041] In one embodiment that may be combined with one or more of the above embodiments, process chamber 402 is disposed adjacent to process chamber 408. In one embodiment, process chamber 404 is disposed adjacent to process chamber 402. In one embodiment that may be combined with one or more of the above embodiments, process chamber 406 is disposed adjacent to process chamber 404. In one embodiment that may be combined with one or more of the above embodiments, each of process chambers 402, 404, 406, and 408 corresponds to process chamber 100 illustrated in FIG. 1 .

[0042] The transfer chamber 420 enables transfer of substrates between the load lock chambers 410 and 412 and the processing chambers 402, 404, 406, and 408. A transfer robot 414 is disposed in the transfer chamber 420. The transfer robot 414 can be a single-blade robot or a dual-blade robot. The transfer robot 414 has a substrate transfer blade 416 attached to the distal end of an extendable arm. The blade 416 is used to support and carry each substrate between the processing chambers 402, 404, 406, and 408. The transfer chamber 420 is maintained in a vacuum or reduced-oxygen environment.

[0043] Controller 430 is coupled to apparatus 400. Controller 430 includes a central processing unit (CPU) (not shown). Controller 430 can be any form of a general-purpose computer processor that can be used to control various processing chambers and sub-processors. Controller 430 can be coupled to individual or shared controllers for processing chambers 402, 404, 406, and 408. Controller 430 can control the movement of transfer robot 414 for transferring substrates within apparatus 400.

[0044] In one embodiment, which may be combined with one or more of the above embodiments, adjacent processing chambers (e.g., processing chambers 402 and 408) share a gas delivery system, RF source, controller, and / or vacuum system. These shared systems increase the throughput of processes performed in the processing chambers and the consistency of deposited films. Sharing the systems also reduces costs associated with the processes.

[0045] Benefits of the present disclosure include a filter circuit that reduces the amount of RF current that could propagate to and damage the DC power supply (e.g., RF leakage). The filter circuit enables the RF current to be directed away from the DC power supply and back to the RF source. The filter circuit also prevents power loss to the clamping electrode and loss of clamping force applied to the substrate.

[0046] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, the scope of which is to be determined by the following claims.

[0047] 100: Processing chamber 102: Chamber body 104: Cover 106: Rod 108: Gas distribution plate 110: Air chamber 112: Hole 114: substrate support 115:Electrostatic chuck 116: Surface 118: Electrode 120: Processing volume 122: Electrode 124:Controller 126: Gas delivery system 128:Conveyor line 130:Filter circuit 132: Power Supply 134: Radio Frequency (RF) Source 136: Impedance matching circuit 138A:Frequency Generator 138B:Frequency Generator 200:Filter circuit 202: First inductor 204: first capacitor 206: Second inductor 208: Second capacitor 210: Third inductor 212: The third capacitor 214: Resistor 230: first inductor group 231: Part 1 232: Second inductor group 233: Part 2 234:Capacitor Bank 236: The third inductor group 240a: Inductor 240b: Inductor 240c: Inductor 240d: Inductor 242a: Inductor 242b: Inductor 242c: Inductor 242d: Inductor 244a: Inductor 244b: Inductor 244c: Inductor 246:Capacitor 248:Capacitor 250:Capacitor 252:Capacitor 254: Shunt capacitor 260: Part 1 262: Part 2 270:Filter circuit 300: Impedance matching circuit 304: Second variable capacitor 306: first variable capacitor 308: Inductor 400: Equipment 402: Processing chamber 404: Processing chamber 406: Processing chamber 408: Processing chamber 410: Loading lock chamber 412: Loading lock chamber 414:Transmission robot 416: Blade 420:Transfer chamber 430: Controller

Claims

1. A device for applying radio frequency power, comprising: A chamber body and a cover, the chamber body and the cover defining a processing volume within the chamber body and the cover; A substrate support disposed within the processing volume; a first electrode embedded in the substrate support; a radio frequency (RF) source coupled to the first electrode; an impedance matching circuit disposed between the RF source and the first electrode; a second electrode embedded in the substrate support; a power source coupled to the second electrode; and an electrode filter disposed between and coupled to the second electrode and the power source, wherein the electrode filter includes: a first inductor group coupled to the second electrode, the first inductor group including a first plurality of inductors connected in parallel; A second inductor group connected in series with the first inductor group, the second inductor group comprising a second plurality of inductors connected in parallel; a third inductor group connected in series with the first inductor group and the second inductor group, the third inductor group comprising a third plurality of inductors connected in parallel, wherein the third inductor group is coupled to the power source; a first ground path coupled to the electrode filter between the second inductor group and the third inductor group, the first ground path comprising a capacitor group; and a second ground path coupled to the electrode filter between the third inductor group and the power source, the second ground path comprising a shunt capacitor.

2. The device as claimed in claim 1, wherein the second electrode includes a conductive mesh.

3. The device as claimed in claim 1, wherein the impedance matching circuit comprises: A first capacitor; An inductor, which is connected in series with the first capacitor and coupled to the first electrode; and a grounding path upstream of the first capacitor, the grounding path including a second capacitor.

4. The device as claimed in claim 3, wherein the first capacitor and the second capacitor are variable capacitors.

5. The device as described in claim 1, further comprising: A gas distribution plate is coupled to the chamber body and supported relative to the substrate.

6. The device as claimed in claim 5, wherein the second electrode is disposed between the first electrode and a surface of the substrate support facing the gas distribution plate.

7. An apparatus for applying radio frequency power, comprising: A chamber body and a cover, the chamber body and the cover defining a processing volume within the chamber body and the cover; A gas distribution plate disposed in the processing volume and coupled to the chamber body; a substrate support disposed in the processing volume; a first electrode embedded in the substrate support; and a power source coupled to the first electrode. An electrode filter is disposed between the first electrode and the power source. The electrode filter includes: a first inductor group coupled to the first electrode, the first inductor group including a first plurality of inductors connected in parallel. A second inductor group connected in series with the first inductor group, the second inductor group comprising a second plurality of inductors connected in parallel; a third inductor group connected in series with the first inductor group and the second inductor group, the third inductor group comprising a third plurality of inductors connected in parallel, wherein the third inductor group is coupled to the power source; a first ground path coupled to the electrode filter between the second inductor group and the third inductor group, the first ground path comprising a capacitor group; and a second ground path coupled to the electrode filter between the third inductor group and the power source, the second ground path comprising a shunt capacitor.

8. The device as claimed in claim 7, wherein the first electrode includes a conductive mesh.

9. The device as claimed in claim 7, comprising: a second electrode embedded in the substrate support; a radio frequency (RF) source coupled to the second electrode; and an impedance matching circuit disposed between the RF source and the second electrode.

10. The device as claimed in claim 9, wherein the first electrode is disposed between the second electrode and a surface of the substrate support facing the gas distribution plate.

11. The device as claimed in claim 9, wherein the impedance matching circuit comprises: A first capacitor; An inductor, which is connected in series with the first capacitor and coupled to the second electrode; and a grounding path upstream of the first capacitor, the grounding path including a second capacitor.

12. The apparatus as claimed in claim 11, wherein the first capacitor and the second capacitor are variable capacitors.

13. An apparatus for applying radio frequency power, comprising: A chamber body and a cover, the chamber body and the cover defining a processing volume within the chamber body and the cover; A gas distribution plate disposed in the processing volume and placed adjacent to the cover; a substrate support disposed in the processing volume; a first electrode embedded in the substrate support; a second electrode embedded in the substrate support between the first electrode and a surface of the substrate support facing the cover; a radio frequency (RF) source coupled to the first electrode; an impedance matching circuit disposed between the RF source and the first electrode; a power source coupled to the second electrode; and an electrode filter disposed between the second electrode and the power source, the electrode filter comprising: a first inductor group coupled to the second electrode, the first inductor group comprising a first plurality of inductors connected in parallel; A second inductor group connected in series with the first inductor group, the second inductor group comprising a second plurality of inductors connected in parallel; a third inductor group connected in series with the first inductor group and the second inductor group, the third inductor group comprising a third plurality of inductors connected in parallel, wherein the third inductor group is coupled to the power source; a first ground path coupled to the electrode filter between the second inductor group and the third inductor group, the first ground path comprising a capacitor group; and a second ground path coupled to the electrode filter between the third inductor group and the power source, the second ground path comprising a shunt capacitor.

14. The device as claimed in claim 13, wherein the second electrode includes a conductive mesh.

15. The device as claimed in claim 14, wherein the conductive mesh is made of an aluminum-containing material.

16. The device as claimed in claim 13, wherein the second electrode generates an electrostatic force on the surface supported by the substrate.

17. The device as claimed in claim 13, wherein the impedance matching circuit comprises: A first capacitor; An inductor, which is connected in series with the first capacitor and coupled to the first electrode; and a grounding path upstream of the first capacitor, the grounding path including a second capacitor.

18. The apparatus as claimed in claim 17, wherein the first capacitor and the second capacitor are variable capacitors.

19. The device as claimed in claim 13, wherein each of the first plurality of inductors and the second plurality of inductors comprises four inductors.

20. The device as claimed in claim 13, wherein the third plurality of inductors includes three inductors.

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