RF electrostatic chuck filter circuit

Abstract

To provide a device and method for greatly reducing the occurrence of high-frequency (RF) coupling through chuck electrodes.SOLUTION: In a processing chamber 100, a chuck electrode 122 is disposed in an electrostatic chuck 115 positioned on a substrate support 114. The substrate support is connected to a chamber body 102. A plasma is generated in a processing space 120 adjacent to the substrate support using an RF source 134. An impedance matching circuit 136 is disposed between the RF source and an electrode 118 disposed on the substrate support. An electrostatic chuck filter 130 is connected between the chuck electrode and a chuck power supply 132.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD

[0001]

[0001] Embodiments of the present disclosure relate generally to semiconductor processing, and more specifically, to an apparatus and method for generating and controlling radio frequency plasma for thin film deposition.

BACKGROUND ART

[0002] Description of Related Art

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

[0003]

[0003] In some embodiments, the electromagnetic energy used to generate the plasma may be radio frequency (RF) power. However, when RF power is used, capacitive coupling may occur between the plasma and the chuck electrode in the electrostatic chuck. The capacitive coupling results in RF coupling, inducing high RF voltages and currents on and through the chuck electrode, which in turn leads to power loss and damage to the power supply of the chuck electrode.

[0004]

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

SUMMARY OF THE INVENTION

[0005]

[0005] In one embodiment, an apparatus is provided that includes a chamber body and a lid defining a processing space therein. A substrate support is disposed within the processing space. 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 supply is coupled to the second electrode. An electrode filter is disposed between and coupled to the second electrode and the power supply.

[0006]

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

[0007]

[0007] In yet another embodiment, an apparatus is provided that includes a chamber body and a lid defining a processing space inside it. A gas distribution plate is located in the processing space and positioned adjacent to the lid. A substrate support is located in the processing space. A first electrode is embedded in the substrate support. A second electrode is embedded in the substrate support between the first electrode and the surface of the substrate support facing the lid. A radio frequency (RF) source is connected to the first electrode. An impedance matching circuit is located between the RF source and the first electrode. A power supply is connected to the second electrode. An electrode filter is located between the second electrode and the power supply. The electrode filter includes a first inductor connected to the second electrode, a second inductor in series with the first inductor, a third inductor in series with the first and second inductors, and a resistor in series with the first, second, and third inductors. The resistor is connected to the power supply. The electrode filter also includes a first capacitor in parallel with the second inductor, a first grounding path connected to the electrode filter between the second inductor and the third inductor, and a second grounding path connected to the electrode filter between the third inductor and the resistor. The first grounding path includes the second capacitor. The second grounding path includes the third capacitor.

[0008]

[0008] To enable a more detailed understanding of the features of the Disclosure described above, a more specific description of the Disclosure, which has been briefly summarized above, can be obtained by reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings only illustrate exemplary embodiments and should not be considered to limit the scope, and the Disclosure may permit other equally effective embodiments. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram of a processing chamber according to one embodiment. [Figure 2A] This is a schematic diagram of a filter circuit according to one embodiment. [Figure 2B]This is a schematic diagram of a filter circuit according to one embodiment. [Figure 3] This is a schematic diagram of an impedance matching circuit according to one embodiment. [Figure 4] This is a plan view of a cluster tool device according to one embodiment described in this book. [Modes for carrying out the invention]

[0010]

[0014] For ease of understanding, the same reference numerals were used to indicate identical elements common to the figures where possible. Elements and features of one embodiment are considered to be usefully incorporated into other embodiments without further description.

[0011]

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

[0012]

[0016] Figure 1 is a schematic diagram of a processing chamber 100 according to a particular embodiment. The processing chamber 100 includes a chamber body 102 and a lid 104 that defines a processing space 120 inside it. A substrate support 114 and a gas distribution plate 108 are arranged in the processing space 120. The substrate support 114 is supported within the chamber body 102 via a stem 106. The substrate support 114 includes one or more conductive plates, insulating plates, equipment plates, cooling channels, etc., to facilitate the processing of the substrate. In one embodiment, the stem 106 is substantially perpendicular to the lid 104 and is connected to the chamber body 102 on the opposite side of the lid 104, or is arranged through an opening in the chamber body 102 on the opposite side of the lid.

[0013]

[0017] In one embodiment, which can be combined with one or more embodiments described above, the substrate support 114 is manufactured from an aluminum-containing material. For example, the substrate support 114 may be manufactured from an aluminum nitride material. To facilitate the fixing of the substrate during processing, an electrostatic chuck 115 can be positioned on the upper surface of the substrate support 114. The electrostatic chuck 115 includes an electrode 122 disposed inside it. In one embodiment, which can be combined with one or more embodiments described above, the electrode 122 is a conductive mesh.

[0014]

[0018] The upper surface 116 of the electrostatic chuck 115 may have a plurality of raised portions (not shown) formed thereon. These raised portions can contact a substrate (not shown) placed on the upper surface 116 of the electrostatic chuck 115. A gas can be flowed 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 thermal equilibrium between the substrate and the substrate support 114. In such embodiments, the temperature of the fluid can be controlled, for example, via a heat exchanger.

[0015]

[0019] The gas distribution plate 108 is connected to the chamber body 102. The plenum 110 is defined between the lid 104 and the gas distribution plate 108. The gas distribution plate 108 is positioned on the opposite side of the substrate support 114. Multiple holes 112 are formed through the gas distribution plate 108. The multiple holes 112 are distributed throughout the gas distribution plate 108 to facilitate the flow of processing gas into the processing space 120.

[0016]

[0020] The gas supply system 126 is connected to the lid 104 via a supply line 128. The gas supply system 126 supplies one or more gases to the processing chamber 100 to process the substrate placed inside it. Once 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 the entire surface 116 of the electrostatic chuck 115.

[0017]

[0021] The electrode 118 is embedded in the substrate support 114. Radio frequency (RF) power is supplied to the electrode 118 via an RF source 134. The RF source 134 is coupled to the electrode 118 via an impedance matching circuit 136. The RF source 134 can supply RF power to the electrode 118 simultaneously at one or more frequencies. For example, the RF source 134 supplies RF power to the electrode at frequencies of approximately 13.56 MHz and approximately 40 MHz. To do so, the RF source 134 includes frequency generators 138A and 138B for each frequency. Although two frequency generators 138A and 138B are shown, the RF source 134 can include any number of frequency generators for each frequency used. The characteristic impedance of the RF source 134 is approximately 50 ohms.

[0018]

[0022] The impedance matching circuit 136 enables the striking and maintenance of the plasma within the processing space 120. The impedance matching circuit 136 couples RF signals of various frequencies from the RF source 134. The impedance matching circuit 136 transmits the coupled RF signals to electrodes 118 embedded in the electrostatic chuck 115. The coupled RF signals are transmitted to the processing gas within the processing space 120, generating a capacitively coupled plasma within it. The chamber body 102 is connected to ground and provides an RF return path to facilitate the generation of the capacitively coupled plasma.

[0019]

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

[0020]

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

[0021]

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

[0022]

[0026] As plasma is generated in the processing space 120, RF current enters the electrode 122 and travels toward the power supply 132 (e.g., RF leakage). The RF current that enters and passes through the power supply 132 may damage the power supply 132, resulting in power loss to the electrode and consequent loss of chucking force applied to the substrate disposed thereon. To prevent damage to the power supply 132, a filter circuit 130 is disposed between the power supply 132 and the electrode 122.

[0023]

[0027] The filter circuit 130, such as an RF filter, substantially blocks RF current from entering the power supply 132. In this way, the filter circuit 130 significantly reduces the occurrence of damage to the power supply 132 by redirecting the RF current (e.g., to ground). The input impedance of the filter circuit 130 is sufficiently high with respect to ground, so that minimal current is diverted from the substrate and the plasma. However, the impedance of the filter circuit 130 is low and sufficient to substantially prevent current from entering the power supply 132.

[0024]

[0028] The controller 124 is coupled to the processing chamber 100 and controls various aspects of the processes performed within the processing chamber. For example, the controller 124 controls the flow rate of the processing gas from the gas supply system 126 to the processing space 120. In addition, the controller 124 can control the manner in which substrates are transferred into and out of the processing chamber 100. Further, the controller 124 can control aspects of the impedance matching circuit 136 and the filter circuit 130, such as the capacitance of the variable capacitor.

[0025]

[0029] Figure 2A is a schematic diagram of a filter circuit 200 according to one embodiment. The filter circuit 200 can correspond to the filter circuit 130 described above with respect to Figure 1. The filter circuit 200 includes a first inductor 202 connected to electrodes such as the electrode 122 shown in Figure 1. A second inductor 206 is arranged in series with the first inductor 202. A third inductor 210 is arranged in series with the first inductor 202 and the second inductor 206. A resistor 214 is arranged in series with the first inductor 202, the second inductor 206, and the third inductor 210. The resistor 214 is connected to a power supply such as the power supply 132 shown in Figure 1.

[0026]

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

[0027]

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

[0028]

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

[0029]

[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 adjusted based on one or more frequencies of the RF current flowing through them. For example, in one embodiment that can be combined with one or more embodiments described above, the first inductor 202 has an inductance from about 14 μH to about 25 μH (e.g., about 20 μH), the third inductor 210 has an inductance from about 8 μH to about 13 μH (e.g., about 10 μH), the second capacitor 208 and the third capacitor 212 have inductances from about 800 pF to about 15000 pF (e.g., about 1000 pF), and the resistor has a resistance from about 1 Ω to about 5 Ω (e.g., about 2 Ω).

[0030]

[0034] A resonant LC circuit including a first capacitor 204 and a second inductor 206 can have a resonant frequency of 40 MHz. The values ​​of the components of the first part 231 (e.g., the first inductor 202, the second inductor 206, and the first capacitor 204) can be based on an input frequency of 13.56 MHz. That is, the first part 231 can be designed to reject RF current at a frequency of 13.56 MHz.

[0031]

[0035] Advantageously, the filter circuit 200 shown in Figure 2A significantly reduces the RF current flowing from the electrode 122 to the power supply 132 shown in Figure 1. Therefore, the filter circuit 200 significantly reduces the occurrence and amount of damage to the power supply.

[0032]

[0036] Figure 2B is a schematic diagram of a filter circuit 270 according to one embodiment. The filter circuit 270 can correspond to the filter circuit 130 described in relation to Figure 1 above. In other words, the filter circuit 270 can be an alternative design to the filter circuit 200 described in relation to Figure 2A.

[0033]

[0037] The filter circuit 270 includes a first section 260 and a second section 262. The first section 260 includes a first bank of inductors 230 and a second bank of inductors 232 in series. The second section 262 includes a bank of capacitors 234, a third bank of inductors 236, and a shunt capacitor 254. The bank of capacitors 234 and the shunt capacitor 254 are in parallel. As shown, the first bank of inductors 230 includes four inductors 240a, 240b, 240c, and 240d in parallel. The second bank of inductors 232 includes four inductors 242a, 242b, 242c, and 242d in parallel. The first section 260 of the filter circuit 270 has a coupled inductance of 20 μH.

[0034]

[0038] As illustrated, the second part 262 of the filter circuit 270 is a low-pass filter. The capacitor bank 234 includes four capacitors 246, 248, 250, and 252. The third bank of inductors includes three inductors 244a, 244b, and 244c in parallel. The capacitance of each capacitor 246, 248, 250, 252, and 254 is 1000pF. The inductance of the third bank of inductors 236 is approximately 10μH. The values ​​of the components of the filter circuit 270 can be adjusted based on one or more input frequencies to be filtered out by the filter circuit 270.

[0035]

[0039] Figure 3 is a schematic diagram of an impedance matching circuit 300 according to one embodiment. The impedance matching circuit 300 includes a first variable capacitor 306 and an inductor 308 in series. A second variable capacitor 304 is connected to ground and to the impedance matching circuit 300 upstream of the first variable capacitor 306. The impedance matching circuit 300 provides the input impedance of the plasma formed in the processing chamber (e.g., processing chamber 100) described with respect to Figure 1 above.

[0036]

[0040] Figure 4 is a plan view of a cluster tool apparatus 400 according to one embodiment described in this book. The apparatus 400 includes a plurality of processing chambers 402, 404, 406, and 408, a transfer chamber 420, and load lock chambers 410 and 412. Each of the processing chambers 402, 404, 406, and 408 is connected to the transfer chamber 420. Although four processing chambers 402, 404, 406, and 408 are shown in Figure 4, any number of processing chambers can be connected to the transfer chamber 420.

[0037]

[0041] In one embodiment, which can be combined with one or more embodiments described above, processing chamber 402 is located adjacent to processing chamber 408. In one embodiment, processing chamber 404 is located adjacent to processing chamber 402. In one embodiment, which can be combined with one or more embodiments described above, processing chamber 406 is located adjacent to processing chamber 404. In one embodiment, which can be combined with one or more embodiments described above, each processing chamber 402, 404, 406, and 408 corresponds to the processing chamber 100 shown in Figure 1.

[0038]

[0042] The transfer chamber 420 can transfer substrates between the load lock chambers 410, 412 and the processing chambers 402, 404, 406, and 408. A transfer robot 414 is positioned inside the transfer chamber 420. The transfer robot 414 may 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 a telescopic arm. The blade 416 is used to support and transport individual substrates between the processing chambers 402, 404, 406, and 408. The transfer chamber 420 is maintained under vacuum, or otherwise in a reduced oxygen environment.

[0039]

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

[0040]

[0044] In one embodiment, which can be combined with one or more embodiments described above, adjacent processing chambers, such as processing chambers 402 and 408, have a shared gas supply system, RF source, controller, and / or vacuum system. These shared systems increase the throughput of the processing performed within the processing chambers and the uniformity of the deposited film. The shared systems also reduce the costs associated with the processing.

[0041]

[0045] The benefits of the disclosure include a filter circuit to reduce the amount of RF current (e.g., RF leakage) that enters the DC power supply and damages it. The filter circuit allows the RF current to be redirected away from the DC power supply and back towards the RF source. The filter circuit also prevents power loss to the chuck electrodes and loss of chucking force applied to the substrate.

[0042]

[0046] While the above description applies to embodiments of the present disclosure, other embodiments and further embodiments of the present disclosure can be devised without departing from the basic scope of the present disclosure, and the scope of the present disclosure is defined by the following claims.

Claims

1. A device for applying high-frequency power, The chamber body and a lid that defines the processing space inside it, A substrate support arranged within the processing space, A first electrode embedded in the substrate support, A radio frequency (RF) source connected to the first electrode, An impedance matching circuit is disposed between the RF source and the first electrode, A second electrode embedded in the substrate support, A power supply connected to the second electrode, An electrode filter positioned between the second electrode and the power supply and connected thereto, A first row of inductors, including a plurality of first inductors connected in parallel to the second electrode, A second row of inductors is connected in series with the first row of inductors and includes a second group of inductors in parallel, A third row of inductors is connected in series with the first row of inductors and the second row of inductors, and includes a third plurality of inductors in parallel, and is connected to the power supply. A first grounding path, which includes a row of capacitors, is connected to the electrode filter between the second row of inductors and the third row of inductors, A second grounding path, including a shunt capacitor, is connected to the electrode filter between the third row of the inductor and the power supply, Electrode filters, Equipped with, A device in which a first portion of the electrode filter, including a first row of inductors and a second row of inductors, is configured to remove 13.56 MHz RF current and 40 MHz RF current, and a second portion of the electrode filter, including a third row of inductors, a first grounding path, and a second grounding path, is configured to remove the remaining RF current.

2. The apparatus according to claim 1, wherein the second electrode comprises a conductive mesh.

3. The impedance matching circuit described above is The first capacitor and, An inductor connected in series with the first capacitor and connected to the first electrode, A grounding path located upstream of the first capacitor and including the second capacitor, The apparatus according to claim 1, comprising:

4. The apparatus according to claim 3, wherein the first capacitor and the second capacitor are variable capacitors.

5. The apparatus according to claim 1, further comprising a gas distribution plate connected to the chamber body and positioned on the opposite side of the substrate support.

6. The apparatus according to claim 5, wherein the second electrode is disposed between the first electrode and the surface of the substrate support facing the gas distribution plate.

7. A device for applying high-frequency power, The chamber body and a lid that defines the processing space inside it, A gas distribution plate connected to the chamber body and positioned within the processing space, A substrate support arranged within the processing space, A first electrode embedded in the substrate support, A power supply connected to the electrode 1, An electrode filter disposed between the above-mentioned first electrode and the power supply, A first row of inductors, including a plurality of first inductors connected in parallel to the first electrode, A second row of inductors is connected in series with the first row of inductors and includes a second group of inductors in parallel, A third row of inductors is connected in series with the first row of inductors and the second row of inductors, and includes a third plurality of inductors in parallel, and is connected to the power supply. A first grounding path, which includes a row of capacitors, is connected to the electrode filter between the second row of inductors and the third row of inductors, A second grounding path, including a shunt capacitor, is connected to the electrode filter between the third row of the inductor and the power supply, Electrode filters, Equipped with, A device in which a first portion of the electrode filter, including a first row of inductors and a second row of inductors, is configured to remove 13.56 MHz RF current and 40 MHz RF current, and a second portion of the electrode filter, including a third row of inductors, a first grounding path, and a second grounding path, is configured to remove the remaining RF current.

8. The apparatus according to claim 7, wherein the first electrode comprises a conductive mesh.

9. A second electrode embedded in the substrate support, A radio frequency (RF) source connected to the second electrode, An impedance matching circuit is disposed between the RF source and the second electrode, The apparatus according to claim 7, further comprising:

10. The apparatus according to claim 9, wherein the first electrode is disposed between the second electrode and the surface of the substrate support facing the gas distribution plate.

11. The impedance matching circuit described above is The first capacitor and, An inductor in series with the first capacitor, A grounding path located upstream of the first capacitor and including the second capacitor, The apparatus according to claim 9, comprising:

12. The apparatus according to claim 11, wherein the first capacitor and the second capacitor are variable capacitors.

13. A device for applying high-frequency power, The chamber body and a lid that defines the processing space inside it, A gas distribution plate is disposed within the processing space and positioned adjacent to the lid, A substrate support arranged within the processing space, A first electrode embedded in the substrate support, A second electrode embedded in the substrate support between the first electrode and the surface of the substrate support facing the lid, A radio frequency (RF) source connected to the first electrode, An impedance matching circuit is disposed between the RF source and the first electrode, A power supply connected to the second electrode, An electrode filter disposed between the second electrode and the power supply, A first row of inductors, including a plurality of first inductors connected in parallel to the second electrode, A second row of inductors is connected in series with the first row of inductors and includes a second group of inductors in parallel, A third row of inductors is connected in series with the first row of inductors and the second row of inductors, and includes a third plurality of inductors in parallel, and is connected to the power supply. A first grounding path, which includes a row of capacitors, is connected to the electrode filter between the second row of inductors and the third row of inductors, A second grounding path, including a shunt capacitor, is connected to the electrode filter between the third row of the inductor and the power supply, Electrode filters, Equipped with, A device in which a first portion of the electrode filter, including a first row of inductors and a second row of inductors, is configured to remove 13.56 MHz RF current and 40 MHz RF current, and a second portion of the electrode filter, including a third row of inductors, a first grounding path, and a second grounding path, is configured to remove the remaining RF current.

14. The apparatus according to claim 13, wherein the second electrode comprises a conductive mesh.

15. The apparatus according to claim 14, wherein the conductive mesh is formed from an aluminum-containing material.

16. The apparatus according to claim 13, wherein the second electrode generates an electrostatic force on the surface of the substrate support.

17. The impedance matching circuit described above is The first capacitor and, An inductor in series with the first capacitor, A grounding path located upstream of the first capacitor and including the second capacitor, The apparatus according to claim 13, comprising:

18. The apparatus according to claim 17, wherein the first capacitor and the second capacitor are variable capacitors.

19. The apparatus according to claim 13, wherein each of the first plurality of inductors and the second plurality of inductors includes four inductors.

20. The apparatus according to claim 13, wherein the third plurality of inductors includes three inductors.

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