Rf filter topology for substrate support assembly

Abstract

An RF filter assembly for processing coupled RF power to a substrate support assembly from a process chamber, a chucking circuit for the substrate support assembly, and a method for processing the coupled RF power are described herein. The RF filter assembly includes a compensation circuit connected to an electrode of the substrate support assembly and configured to receive the coupled RF power and reduce reflections of the coupled RF power back to the substrate support assembly, and an RF filter block configured to receive signals processed by the compensation circuit and including a plurality of RF filters configured to filter out predetermined frequencies of the coupled RF power. The chucking circuit includes the RF filter assembly. The method includes processing and operation of the RF filter assembly.

Description

Technical Field

[0001] The embodiments described herein generally relate to an RF filter topology for a substrate support assembly and a plasma processing chamber containing the substrate support assembly. Background Technology

[0002] Related technical descriptions

[0003] Current plasma-based substrate processing involves controlling dimensional uniformity during plasma deposition and / or etching. During plasma processing, substrate temperature is the primary factor affecting dimensional uniformity. Substrate support assemblies are typically used to support and heat the substrate during processing. Therefore, it is necessary to control the heat supplied to the substrate support assemblies to maintain the substrate temperature within a desired range.

[0004] The substrate support assembly includes several electrodes: power electrodes for supplying RF voltage to excite process gases, clamping electrodes for supplying DC voltage to clamp the substrate, and heating electrodes for supplying current to heat the substrate. Although each electrode is housed in a corresponding circuit, capacitive coupling may occur between these electrodes due to their close proximity within the substrate support assembly. Capacitive coupling can generate coupled RF power in the clamping and / or heating circuits. This coupled RF power can not only cause safety issues but also cause unintended damage to the electrical and hardware components in the clamping and heating circuits. To mitigate safety issues and damage to other electrical components, RF filters have been included in the circuitry. However, when these additional RF filter blocks are added, the substrate support assembly may experience undesirable temperature fluctuations.

[0005] Therefore, an improved RF filter topology for substrate support assemblies is needed. Summary of the Invention

[0006] This document describes an RF filter assembly for blocking unwanted RF signals and noise, including coupled RF power coupled through a substrate support assembly of a processing chamber (such as a clamping circuit or a heating circuit disposed within the substrate support assembly). A method of processing the RF filter assembly is also described. The RF filter assembly includes compensation circuitry connected to electrodes of the substrate support assembly and configured to block coupled RF power coupled through circuitry containing electrodes (such as a DC circuit for clamping electrodes or an AC circuit for heating electrodes). The RF filter assembly includes at least one RF filter configuration, such as a low-pass filter, a band-stop filter, or any other suitable filter, configured to filter out a predetermined frequency of the coupled RF power. In one example, the RF filter assembly includes a compensation circuit having a first input configured to receive coupled RF power and reduce coupled RF power returning through the first input; and an RF filter block having a second input configured to receive a signal processed by the compensation circuit and including one or more RF filters configured to filter out predetermined frequencies of coupled RF power.

[0007] The clamping circuit for the substrate support assembly of the processing chamber includes clamping electrodes coupled to a distribution box. The distribution box includes a compensation circuit connected to the electrodes of the substrate support assembly and configured to receive coupled RF power and reduce the coupled RF power returning to the substrate support assembly. The distribution box further includes an RF filter block configured to receive signals processed by the compensation circuit and includes one or more RF filters, such as RF low-pass or band-stop filters, configured to filter out predetermined frequencies of the coupled RF power.

[0008] A method for processing coupled RF power originating from a substrate support assembly within a processing chamber includes directly transmitting the coupled RF power from electrodes within the substrate support assembly to a compensation circuit. The electrodes include clamping electrodes or heating electrodes. The method further includes reducing the coupled RF power returning to the electrodes via the compensation circuit, wherein the compensation circuit includes an inductor connected to a first ground capacitor, and the inductor includes an inductor, a segment of a transmission line, or a combination of an inductor and a segment of a transmission line. The method further includes directly transmitting the coupled RF power processed by the compensation circuit to a first RF band-stop filter configured to filter out a first frequency of the coupled RF power, the first frequency corresponding to the highest frequency of the RF signal that generates the coupled RF power. The method further includes transmitting the output of the first RF band-stop filter to a second RF band-stop filter configured to filter out a second frequency of the coupled RF power, the second frequency corresponding to the lowest frequency of the RF signal that generates the coupled RF power; and coupling the second RF band-stop filter to a high-voltage module. Attached Figure Description

[0009] To gain a more detailed understanding of the features described above in this disclosure, a more specific description of the disclosure, which has been briefly outlined above, can be obtained by referring to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only typical embodiments of this disclosure and should not be construed as limiting its scope, as other equally effective embodiments are permissible.

[0010] Figure 1 A schematic cross-sectional view of an example of a processing chamber according to one embodiment is shown.

[0011] Figure 2 A schematic cross-sectional view of an example of a substrate support assembly according to one embodiment is shown.

[0012] Figure 3 A schematic circuit diagram of the clamping circuit according to an embodiment is shown.

[0013] Figure 4 The diagram illustrates the detailed connections between the electrical components of an exemplary clamping circuit according to an embodiment of this application.

[0014] Figure 5a illustrates the detailed connections between the electrical components of the compensation circuit according to the embodiment.

[0015] Figure 5b illustrates the detailed connections between the electrical components of a compensation circuit according to another embodiment.

[0016] Figure 6a shows a schematic perspective view of a distribution box containing a clamping circuit for an RF filter assembly according to an embodiment.

[0017] Figure 6b illustrates a schematic top view of a distribution box containing a clamping circuit for an RF filter assembly according to an embodiment.

[0018] Figure 6c illustrates a schematic cross-sectional view of a distribution box containing a clamping circuit for an RF filter assembly according to an embodiment.

[0019] Figure 7 A method for processing coupled RF power transmitted by electrodes in a processing chamber, according to an embodiment, is illustrated.

[0020] For ease of understanding, the same reference numerals have been used to denote common elements in the figures where possible. It is contemplated that elements and features of one embodiment may be advantageously incorporated into other embodiments without further elaboration. Detailed Implementation

[0021] The embodiments described herein include an RF filter topology for a substrate support assembly. The substrate support assembly is disposed within a processing chamber configured to process the substrate with plasma. The RF filter topology can be disposed within any circuitry where coupled RF power can be detected, such as clamping circuitry and / or heater circuitry. The RF filter topology includes multiple RF filters configured to filter out predetermined frequencies of the coupled RF power. For example, the coupled RF power may include a first low frequency of approximately 100 kHz to 13.56 MHz and a second high frequency of approximately 13.56 MHz to 200 MHz. These low and high frequencies correspond to the frequencies of one or more RF power supplies used by the plasma generation circuitry to generate and sustain plasma within the processing chamber.

[0022] The RF filter topology further includes a compensation circuit disposed between the RF filter and a coupling location that generates coupled RF power. The coupling location may be the upper portion of a substrate support assembly, where clamping and / or heating electrodes are located. For example, when the RF filter topology is disposed within a clamping circuit, the compensation circuit is disposed between the RF filter and the clamping electrode. The compensation circuit is configured to block coupled RF power through the clamping circuit, heater circuit, or other DC / AC lines of the substrate support assembly. If coupled RF power is coupled back to the coupling location (such as the clamping electrode), the coupled RF power can generate additional heat and cause the temperature of the substrate assembly support to fluctuate beyond an desired range. Together with the RF filter, the compensation circuit reduces coupled RF power and provides an improved substrate support assembly for controlling the substrate temperature.

[0023] When the coupling location generating the coupled RF power is considered the source and the RF filter is considered the load, compensation circuitry is configured to compensate for unwanted parasitic effects along the transmission line. Compensation circuitry can be implemented by a combination of electrical components such as inductors, capacitors, resistors, and any other suitable electrical components. In an example, the inductor for the compensation circuitry can also be implemented by a segment of the transmission line extending between the coupling location and the RF filter. Compensation circuitry may also include circuit elements configured to transmit a selected RF frequency to ground.

[0024] Figure 1 A schematic cross-sectional view of a processing chamber 100 configured to perform a plasma process according to an embodiment is illustrated. In this embodiment, the processing chamber 100 is a plasma processing chamber, such as a reactive ion etch (RIE) plasma chamber. In some other embodiments, the processing chamber is a plasma-enhanced deposition chamber, such as a plasma-enhanced chemical vapor deposition (PECVD) chamber, a plasma-enhanced physical vapor deposition (PEPVD) chamber, or a plasma-enhanced atomic layer deposition (PEALD) chamber. In some other embodiments, the processing chamber is a plasma processing chamber or a plasma-based ion implantation chamber, such as a plasma doping (PLAD) chamber.

[0025] like Figure 1 As shown, the processing chamber 100 further includes a chamber body 102, which includes a chamber cover 123, one or more sidewalls 122, and a chamber base 124, defining a processing volume 106. A gas inlet 116 disposed through the chamber cover 123 is used to supply one or more processing gases from a processing gas source 120 in fluid communication with it to the processing volume 106.

[0026] Processing chamber 100 includes a plasma power assembly 140, which includes a radio frequency (RF) power supply 142 coupled to an RF matching circuit 141. The coupled RF power supply 142 receives power from a power generator 150 via a power conditioner 134. In one embodiment, the plasma power assembly generates inductively coupled plasma (ICP) in processing volume 106. In other embodiments, the plasma power assembly 140 generates capacitively coupled plasma (CCP) in processing volume 106. The plasma power assembly 140 includes power electrodes disposed in a substrate support assembly 117. The plasma power assembly 140 may include electrodes disposed in processing volume 106 facing the substrate support assembly 117.

[0027] A plasma power assembly 140 is configured to ignite and sustain the process plasma 107 and is coupled to one or more inductor coils 104 positioned close to a chamber cover 123 outside the process volume 106. In one embodiment, the plasma power assembly 140 applies an RF signal having multiple discrete frequencies. For example, the RF signal includes a first frequency wave with a relatively high fundamental frequency (such as about 42 MHz), which is suitable for generating high-density plasma. Simultaneously, the RF signal includes a second frequency wave with a relatively low fundamental frequency (such as about 13 MHz), which is suitable for directing ions toward the substrate 110. The RF signal may also include other signals whose frequencies are integer multiples of the low fundamental frequency (such as about 27 MHz).

[0028] The processing volume 106 is fluidly coupled to one or more dedicated vacuum pumps 107 via a vacuum outlet 127. The dedicated vacuum pumps 107 maintain the processing volume 106 under sub-atmospheric conditions and evacuate the processing gas and / or other gases therefrom. A substrate support assembly 117 disposed in the processing volume 106 is mounted on a support shaft 138 that extends hermetically through the chamber base 124.

[0029] The substrate 110 is loaded into and removed from the processing volume 106 through an opening (not shown) in one or more sidewalls 122. During processing, the substrate 110 is placed on the substrate support surface 115 of the substrate support assembly 117.

[0030] The substrate support assembly 117 includes a substrate support 111, which includes an ESC substrate support 111A and a support base 111B. Typically, the ESC substrate support 111A is formed of a dielectric material, such as a bulk sintered ceramic material, or a corrosion-resistant metal oxide or metal nitride material, such as alumina (Al₂O₃), aluminum nitride (AlN), titanium oxide (TiO), titanium nitride (TiN), yttrium oxide (Y₂O₃), mixtures thereof, or combinations thereof. The ESC substrate support 111A further includes a clamping electrode 112 embedded in its dielectric material.

[0031] In this embodiment, clamping electrode 112 acts as a clamping electrode to secure (clamp) substrate 110 to substrate support surface 115 and to bias substrate 110 with respect to processing plasma 107. Typically, clamping electrode 112 is formed of one or more conductive components (such as one or more metal meshes, foils, plates, or combinations thereof). Herein, clamping electrode 112 is electrically coupled to high-voltage module 155, which is supplied with a clamping voltage, such as a static DC voltage between approximately -5000 V and approximately 5000 V, using an electrical conductor (such as transmission line 151). Power generator 150 supplies power to high-voltage module 155.

[0032] In some embodiments, the ESC substrate support 111A includes a heater 113, such as a resistance heating element embedded in the dielectric material of the ESC substrate support 111A. The heater 113 generates heat through one or more heating electrodes 114 using AC power supplied by an AC power supply 165. In one embodiment, the one or more heating electrodes 114 are spaced apart from the clamping electrode 112 by a distance. A power generator 150 supplies power to the AC power supply 165.

[0033] According to one embodiment, the high-voltage module 155 is coupled to a first RF filter assembly 153. The RF filter assembly 153 is disposed between the high-voltage module 155 and the clamping electrode 112. In one embodiment, the RF filter assembly 153 is configured to prevent coupled RF power from flowing into the high-voltage module 155. In another embodiment, the RF filter assembly 153 is configured to reduce the reflection of coupled RF power back to the clamping electrode 112. The coupled RF power is caused by capacitive coupling between the clamping electrode 112 and the heating electrode 113 and / or the RF coil 104.

[0034] To filter out coupled RF power, RF filter assembly 153 includes multiple RF filters, such as band-stop filters, whose frequencies correspond to the frequencies of the power signals supplied by plasma power assembly 140 to generate plasma and / or the power signals supplied by AC power supply 165 to generate heat. Other filters, such as low-pass filters, may also be included depending on the frequency of the power signals.

[0035] According to an embodiment, the RF filter assembly 153 includes a compensation circuit 308. Figure 3 As shown in the diagram, the compensation circuit 308 is configured to reduce signal reflection from the RF filter assembly 153 to the substrate support assembly 117. Signals reflected back from the RF filter to the substrate support assembly 117 can be received by the clamping electrode 112 and act as additional heating current flowing to the substrate support assembly 117. Reflected, coupled RF power can cause undesirable temperature fluctuations, which can be particularly problematic when the plasma power assembly 140 provides a large current to generate and sustain the plasma 107.

[0036] like Figure 1 As shown, clamping electrode 112 is coupled to other electrical components, such as high-voltage module 155, RF filter assembly 135, and any other electrical components. In the absence of any impedance matching between clamping electrode 112 and other electrical components, a certain amount of coupled RF power generated by clamping electrode 112 will be coupled back to the coupling location where clamping electrode 112 is positioned. Compensation circuit 308 is configured to reduce the difference between the impedance of the source and the impedance of the load, thereby reducing the reflection coefficient between the source and the load. In this way, the amount of coupled RF power reflected back from the load to the source (such as clamping electrode 112) can be reduced. Compensation circuit 308 provides improved control over undesired heating at substrate support assembly 117. The configuration of RF filter assembly 153 will be described in detail later in this application.

[0037] In one embodiment, an RF filter assembly 160 is disposed between an AC power supply 165 and one or more heating electrodes 114. Similar to RF filter assembly 153, filter assembly 160 further includes a plurality of RF filters configured to prevent any coupled RF power from flowing into the AC power supply 165. Filter assembly 160 further includes compensation circuitry configured to compensate for parasitic effects and reduce coupled RF power coupling back to the heating electrodes 114.

[0038] The support base 111B is electrically isolated from the chamber base 124 via an insulating plate 111C and a ground plane 137 inserted between the insulating plate 111C and the chamber base 124. In some embodiments, the support base 111B includes one or more cooling channels (not shown) disposed therein, which are fluidly coupled and in fluid communication with a coolant source (not shown, such as a refrigerant source with relatively high resistance or a water source). Hereinafter, the support base 111B is formed of a corrosion-resistant, thermally conductive material (such as a corrosion-resistant metal, e.g., aluminum, aluminum alloy, or stainless steel) and is coupled to the substrate support by adhesive or mechanical means.

[0039] Processing chamber 100 further includes a system controller 134. The system controller 134, as described herein, includes a central processing unit (CPU), memory, and supporting circuitry. The system controller 134 controls the process sequence used to process substrate 110. A program (or computer instructions) readable by the system controller 134 determines which tasks are performed by components within processing chamber 100. This program will include instructions for controlling various hardware and electrical components within processing chamber 100 to perform various process tasks and processes to implement the electrode biasing scheme described herein.

[0040] Figure 2 This is a schematic side cross-sectional view of a portion of the substrate support assembly 117. The heater 113 embedded within the ESC substrate support 111A may include multiple heating regions, such as an inner heater region 113A including a first heating electrode 114A and an outer heater region 113B including a second heating electrode 114B. A first side of the first heating electrode 114A is coupled to a first conductive lead 211, and a second side of the first heating electrode 114A is coupled to a second conductive lead 212.

[0041] A power generator 150 is configured to provide nanosecond DC pulses to a clamping electrode 112, or in some configurations, to it coupled RF power, the clamping electrode 112 being capacitively coupled to a plasma 107 via a plurality of series capacitors, including an ESC capacitor C3 and a substrate capacitor C2. The plasma 107 typically has an impedance Z... p The impedance Z p This includes a series of complex impedances, which are caused by the formed plasma and the plasma sheath formed at the chamber walls and on the substrate 110. The electrostatic chuck and the dielectric layer in the substrate 110 separate the clamping electrode 112 from the plasma 107, and in Figure 2 In the circuit, capacitors C3 and C2 represent the components. The clamping electrode 112 also couples the capacitors to the first heating electrode 114A and the second heating electrode 114B. Figure 2The capacitors C4 and C5 represent this respectively. The capacitive coupling between the clamping electrode 112, the heating electrode 114, and the plasma 107 can result in coupled RF power in a circuit containing the clamping electrode 112 and the heating electrode 114 respectively.

[0042] Figure 3 This is a schematic block diagram of a clamping circuit 300 according to an embodiment. The clamping circuit 300 includes a clamping electrode 112, an RF filter assembly 153, a high-voltage module 155, and other optional electrical components 310. The clamping electrode 112 is disposed in a substrate support assembly 117, which is disposed inside a processing chamber 100. The RF filter assembly 153, the high-voltage module 155, and other optional electrical components are disposed outside the processing chamber 100. The clamping electrode 112 is coupled to the RF filter assembly 153 via a transmission line 151. A chamber wall 303 separates the RF filter assembly 153 from the clamping electrode 112. The RF filter assembly 153 includes a compensation circuit 308 and an RF filter block 312, which includes a plurality of RF filters 304 and 306.

[0043] Within the RF filter assembly 153, the coupled RF power 302 first reaches a compensation circuit 308, which is configured to reduce the impedance difference between the clamping electrode 112 and the RF filter block 312. The compensation circuit 308 includes an input 305 that receives the coupled RF power 302 and an output 307 that outputs the processed coupled RF power to the first RF filter 306. The compensation circuit 308 may also include a grounded electrical component 309, which allows the selected RF frequency to be grounded. The compensation circuit 308 outputs the processed signal to the RF filter block 312. In embodiments, the RF filter block 312 includes one or more RF filters, such as an RF low-pass filter, an RF bandgap filter, or any other suitable RF filter. Figure 3 As shown, the RF filter block 312 includes two RF band-stop filters 304 and 306, configured to sequentially filter out two different frequency signals (13 MHz and 42 MHz) from the coupled RF power 302. The clamping electrode 112, the compensation circuit, the RF band-stop filter 306, and the RF band-stop filter 304 are connected in series.

[0044] Due to capacitive coupling with plasma 107 or heating electrode 114, clamping electrode 112 generates coupled RF power 302. Coupled RF power 302 includes RF signals at frequencies identical to those of RF power assembly 140 and / or heating power supply 165. Coupled RF power 302 may also include other frequencies. In one embodiment, coupled RF power 302 includes signals of approximately 13 MHz and 42 MHz. Coupled RF power 302 flows directly from clamping electrode 112 to input 305 of RF filter assembly 153. In one embodiment, RF filter assembly 153 includes at least one RF filter 306. In another embodiment, RF filter assembly 153 includes multiple RF filters 304 and 306. RF filters may include RF low-pass filters, RF band-stop filters, or any other suitable filters. Each of the RF filters is configured to filter out a single-frequency signal. For example, RF filter assembly 135 includes a first RF bandstop filter 306 configured to filter out approximately 42 MHz signals and a second RF filter 304 configured to filter out approximately 13 MHz signals. The plurality of RF filters 304 and 306 are arranged to filter out coupled RF power from the highest frequency to the lowest frequency. Figure 3 As shown, the coupled RF power 302 first reaches a first RF filter 306, which is configured to filter out signals of the highest frequency, such as 42 MHz. The coupled RF power 302 exits the RF filter assembly 153 through a second RF filter 304, which is configured to filter out signals of the lowest frequency, such as 13 MHz.

[0045] Other frequencies of the coupled RF power 302 can be further filtered out by other electrical components 310 connected in series with the RF filter assembly 153. Other electrical components 310 may include a low-pass filter or any other suitable component. Other electrical components 310 may include a grounded electrical component 311.

[0046] like Figure 3 The clamping circuit 300 shown reduces the reflection of the coupled RF power 302 by the RF filter block 312. Therefore, the clamping circuit 300 provides improved control over the heated substrate support assembly 117. Similar to the clamping circuit 300, the heating circuit may be configured to include an impedance compensation block between the heating electrode 114 and other RF filters.

[0047] Figure 4Detailed connections of the electrical components of an exemplary clamping circuit 300 according to an embodiment of this disclosure are illustrated. Coupled RF power 302 flows from the clamping electrode 112 to other electrical components of the clamping circuit 300, such as the high-voltage module 155. A compensation circuit 308 is disposed outside the processing chamber 110. The compensation circuit 308 is disposed between the clamping electrode 112 and other components of the clamping circuit, such as RF band-stop filters 306, 304 and the high-voltage module 155.

[0048] In one embodiment, the compensation circuit 308 includes an inductor L1 411, an energy storage circuit 408, and a capacitor C1 309. The inductor L1 411 is connected in series to the clamping electrode 112 via input 305 and outputs the processed signal to the first RF band-stop filter 306 and the energy storage circuit 408 via node 402. The energy storage circuit 408 is connected in parallel with the RF band-stop filter 306. The energy storage circuit 408 may be a parallel LC circuit including an inductor L2 413 and a capacitor C2 415. The energy storage circuit 408 is connected in series with another grounded capacitor C1 309. In one embodiment, the inductor L1 411 is an inductor. In another embodiment, a segment of the transmission line 151 may be added in series with the inductor or the inductor L1 411 may be replaced. In this way, the use of additional lumped electrical components can be avoided.

[0049] The first RF band-stop filter 306 may be a parallel LC circuit configured to filter out the highest frequency, such as approximately 42 MHz, in the coupled RF power 302. The RF band-stop filter 306 includes an inductor L3 417 and a capacitor C3 419.

[0050] The second RF band-stop filter 304 may be a parallel LC circuit configured to filter out the lowest frequency, such as 13 MHz, in the coupled RF power 302. The RF band-stop filter 304 includes an inductor L4 421 and a capacitor C4 423. The first RF band-stop filter 306 is connected in series with the second RF band-stop filter 304.

[0051] The second RF band-stop filter 304 is connected to the high-voltage module 155 and capacitor C5 311 via node 406. Capacitor C5 311 is grounded. Capacitor C5 311 is connected in parallel to the high-voltage module 155. In this embodiment, capacitor C5 311 acts as a shunt capacitor.

[0052] Figure 5a illustrates a circuit diagram of the compensation circuit 502 according to an embodiment. Figure 4 Compared to the compensation circuit 308 shown, the compensation circuit 502 further includes a capacitor 503 connected in parallel with the inductor L1 411.

[0053] Figure 5b illustrates a circuit diagram of the compensation circuit 504 according to an embodiment. Figure 4 Compared to the compensation circuit 308 shown, compensation circuit 504 removes inductor L1 411 and includes another inductor 505 between node 402 and energy storage circuit 408. Inductor 505 is connected in series to energy storage circuit 408. Inductor 505 may be an inductor, a segment of a transmission line, or a combination of an inductor and a segment of a transmission line.

[0054] Figure 6a shows a schematic perspective view of a distribution box 600 of an RF filter assembly 153 containing a locking circuit 300 according to an embodiment. Figure 6b shows a schematic top view of a distribution box 600 of an RF filter assembly 153 containing a locking circuit 300 according to an embodiment. Figure 6c shows a schematic cross-sectional view of a distribution box 600 of an RF filter assembly 153 containing a locking circuit 300 according to an embodiment.

[0055] As shown in Figure 6a, the distribution box 600 includes a housing 610 that encloses internal components. The housing 610 forms a first chamber 602 containing a high-voltage module 155. The distribution box 600 further includes a plurality of RF components 614 coupled to the housing 610 via a bracket 616. According to an embodiment, the plurality of RF components 614 includes a compensation circuit 308, a first RF band-stop filter 306, a second RF band-stop filter 304, and optional electrical components 310 as described in this application. The housing 610 further forms an upper chamber 604, which contains the bracket 616 and a plurality of connectors 622 coupled to the plurality of RF components 614.

[0056] The distribution box 600 includes a fan 608 that forces air 612 into the housing 610 through a chamber vent 611. The fan 608 and the chamber vent 611 are located on the bottom wall 613 facing the upper chamber 604. The fan 608 forces the air 612 into the first chamber 602, then into the upper chamber 604, and then into the RF component 614. The air 612 exits the RF component 614 through a plurality of vents 620 formed on the housing of the RF component 614. The air 612 transfers heat away from the distribution box 600 and the RF component 614.

[0057] As shown in FIG. 6b, the bracket 616 includes a plurality of connectors 622, each of which is coupled to one of the plurality of RF components 614. The bracket 616 further includes a plurality of vents 624 disposed adjacent to the connectors. According to an embodiment, each of the plurality of RF components 614 includes a cap 626 (shown in FIG. 6c). The cap 626 includes a vent 628 (shown in FIG. 6c), the position and shape of which correspond to the vents 624 in the bracket 616. The alignment between the vents 628 and the vents 624 allows air 612 to flow from the upper chamber 604 to the RF component 614 with reduced resistance.

[0058] Figure 7 A method 700 for processing coupled RF power originating from a substrate support assembly in a processing chamber, according to an embodiment, is illustrated. At operation 702, the substrate support assembly 117 generates coupled RF power due to capacitive coupling between the clamping electrode, heating electrode, and power electrode of the plasma. The coupled RF power is transmitted directly from the electrodes (such as the clamping electrode or heating electrode) to a compensation circuit. At operation 704, the compensation circuit reduces the coupled RF power returning to the electrodes. The compensation circuit includes an inductor connected to a first ground capacitor, and the inductor may include an inductor, a segment of a transmission line, or a combination of an inductor and a segment of a transmission line. At operation 706, the coupled RF power processed by the compensation circuit is transmitted directly to a first RF band-stop filter configured to filter out a first frequency of the coupled RF power, the first frequency corresponding to the highest frequency of the RF signal that generates the coupled RF power. At operation 708, the output of the first RF band-stop filter is transmitted to a second RF band-stop filter configured to filter a second frequency of the coupled RF power, the second frequency corresponding to the lowest frequency of the RF signal that generates the coupled RF power. At operation 710, the second RF band-stop filter is coupled to a high-voltage supply. Method 700 may include other processes and operations as described in this application.

[0059] It is envisioned that one or more aspects disclosed herein may be combined. Furthermore, it is envisioned that one or more aspects disclosed herein may include some or all of the benefits described above. While the foregoing describes embodiments of this disclosure, other and additional embodiments of this disclosure may be devised without departing from its essential scope, as defined by the following claims.

Claims

1. An RF filter assembly, the RF filter assembly comprising: A compensation circuit, comprising a first input configured to receive coupled RF power and reduce the coupled RF power returned through the first input; and An RF filter block, the RF filter block including a second input configured to receive a signal processed by the compensation circuit, and including one or more RF filters configured to filter out a predetermined frequency of the coupled RF power.

2. The RF filter assembly of claim 1, wherein the compensation circuit comprises an inductor component formed by an inductor, a segment of a transmission line, or a combination of an inductor and a segment of a transmission line.

3. The RF filter assembly of claim 2, wherein the inductor is connected to the first input, and the compensation circuit further includes a first capacitor connected to the inductor and grounded.

4. The RF filter assembly of claim 3, wherein the compensation circuit includes a first energy storage circuit connected to the inductor and the first capacitor, and the first energy storage circuit is connected in parallel to the RF filter block.

5. The RF filter assembly of claim 2, wherein the inductor is formed by segments of the transmission line of the compensation circuit.

6. The RF filter assembly of claim 5, wherein the compensation circuit further includes a second capacitor coupled in parallel with the inductor to form a second energy storage circuit.

7. The RF filter assembly of claim 1, wherein the first input is connected to a heating electrode or a clamping electrode of a substrate support assembly.

8. The RF filter assembly of claim 1, wherein the RF filter block comprises a plurality of RF filters connected in series, the plurality of RF filters being configured to filter out predetermined frequencies from the highest frequency to the lowest frequency.

9. The RF filter assembly of claim 1, further comprising a grounded shunt capacitor connected to the RF filter block.

10. The RF filter assembly of claim 9, wherein the RF filter assembly is connected to the high-voltage module, and the ground shunt capacitor is connected in parallel to the high-voltage module.

11. A clamping circuit for a substrate support assembly for a processing chamber, the clamping circuit comprising: The clamping electrode is coupled to the distribution box. The distribution box includes: A compensation circuit, connected to the clamping electrode of the substrate support assembly and configured to receive coupled RF power from the input and reduce the reflection of the coupled RF power returning through the input; and An RF filter block configured to receive a signal processed by the compensation circuit, and comprising a plurality of RF filters configured to filter out predetermined frequencies of the signal processed by the compensation circuit.

12. The clamping circuit of claim 11, wherein the compensation circuit comprises an inductive component formed by an inductor, a transmission line, or a combination of an inductor and a transmission line.

13. The clamping circuit of claim 12, wherein the inductor is connected to the input, and the compensation circuit further includes a first capacitor connected to the inductor and grounded.

14. The clamping circuit of claim 13, wherein the compensation circuit includes a first energy storage circuit, the first energy storage circuit being connected to the inductor and the first capacitor, and the first energy storage circuit being connected in parallel to the RF filter block.

15. The clamping circuit of claim 12, wherein the inductive component is formed by segments of the transmission line of the compensation circuit.

16. The clamping circuit of claim 15, wherein the compensation circuit further comprises a second capacitor, the second capacitor being coupled in parallel with the inductor to form a second energy storage circuit.

17. The clamping circuit of claim 15, wherein the input is connected to the clamping electrode.

18. The clamping circuit of claim 11, wherein the RF filter block comprises a plurality of RF filters connected in series, the plurality of RF filters being configured to filter out predetermined frequencies from the highest frequency to the lowest frequency.

19. The clamping circuit of claim 11, wherein the distribution box includes a first housing enclosing the high-voltage module, a second housing enclosing the compensation circuit, and a bracket coupling the first housing and the second housing, the bracket and the second housing including a plurality of vents that allow air to flow from the first housing to the second housing.

20. A method for processing coupled RF power originating from a substrate support assembly of a processing chamber, the method comprising: The coupled RF power is directly transmitted from the electrodes within the substrate support assembly to the compensation circuit, the electrodes including clamping electrodes or heating electrodes; The compensation circuit reduces the coupled RF power returning to the electrode, wherein the compensation circuit includes an inductor connected to a first ground capacitor, and the inductor includes an inductor, a segment of a transmission line, or a combination of an inductor and a segment of the transmission line. The coupled RF power processed by the compensation circuit is directly transmitted to a first RF band-stop filter, which is configured to filter out a first frequency of the coupled RF power, the first frequency corresponding to the highest frequency of the RF signal that generates the coupled RF power. The output of the first RF band-stop filter is transmitted to a second RF band-stop filter, the second RF band-stop filter being configured to filter a second frequency of the coupled RF power, the second frequency corresponding to the lowest frequency of the RF signal that generates the coupled RF power; and The second RF band-stop filter is coupled to the high-voltage module.

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