Radio frequency grounding system and method

Abstract

The present disclosure provides an apparatus including a chamber body and a lid defining a volume therein. The apparatus includes a substrate support disposed in the volume opposite the lid. The substrate support includes a support body disposed on a backbone; and a ground plate disposed between the support body and the backbone. A top flange is coupled to a lower peripheral surface of the ground plate; and a bottom flange is coupled to a bottom of the chamber body. The bottom flange and the top flange are coupled to each other using a plurality of strips, each of the strips having a first end coupled to the bottom flange and a second end coupled to the top flange.

Description

[0001] background Technical Field

[0002] Embodiments of the present disclosure generally relate to systems and methods for manufacturing semiconductor devices. More specifically, the present disclosure is directed to systems and methods for providing a radio frequency ground path.

[0003] Related technologies

[0004] Plasma enhanced CVD (PECVD) is a process used to deposit films on substrates, such as semiconductor substrates. CVD is accomplished by introducing a process gas into a process chamber containing the substrate. The process gas is directed through a gas distribution assembly and into a processing volume in the process chamber.

[0005] Radio frequency (RF) power is used to activate process gases in a process chamber to create a plasma. The RF power is returned to the source. In some cases, arcing occurs from the RF power in the process chamber, which damages the chamber and its components. Ground paths are provided to direct the RF power away from the components of the process chamber to avoid damage thereto and in an attempt to reduce the occurrence of arcing in the process chamber. However, current ground path designs are complex, expensive, high maintenance over time, and do not completely address arcing in the process chamber.

[0006] Therefore, there is a need for a simple, less expensive, low maintenance, and effective RF return path design. Summary of the invention

[0007] In certain embodiments, an apparatus is provided, including a chamber body and a lid defining a volume therein. The apparatus includes a substrate support disposed in the volume opposite the lid. The substrate support includes a support body disposed on a backbone; and a ground plate disposed between the support body and the backbone. The top flange is coupled to a lower peripheral surface of the ground plate; and the bottom flange is coupled to a bottom of the chamber body. The bottom flange and the top flange are coupled to each other with a plurality of strips, each of the strips having a first end coupled to the bottom flange and a second end coupled to the top flange.

[0008] In certain embodiments, a method of processing a substrate is provided, comprising positioning a substrate on a substrate support in a volume of a process chamber, the substrate support being disposed in the volume opposite a lid. The substrate support comprises a support body disposed on a backbone, a ground plate disposed between the support body and the backbone, and a top flange coupled to a lower peripheral surface of the ground plate. The process chamber comprises a bottom flange coupled to a bottom of the chamber volume, and a plurality of strips, each of the strips having a first end coupled to the bottom flange and a second end coupled to the top flange. The substrate support is raised to a raised position, forming an upper portion of the volume. The method comprises introducing a gas into the upper portion of the volume; and activating the gas using radio frequency energy.

[0009] In certain embodiments, a grounding assembly is provided, including a top flange having a top flange upper surface and a top flange lower surface. The grounding assembly includes a bottom flange having a bottom flange upper surface and a bottom flange lower surface. The bottom flange has a lower portion extending radially inward from an inner diameter of the bottom flange, and the lower portion has one or more openings configured to receive a screw. The grounding assembly includes a plurality of strips, each of the strips including a first end coupled to the bottom flange and a second end coupled to the top flange. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order that the above-mentioned features of the present disclosure may be understood in detail, a more specific description of the present disclosure briefly summarized above may be obtained by reference to the embodiments, some of which are illustrated in the attached drawings. However, it should be understood that the attached drawings only illustrate example embodiments of the present disclosure and therefore should not be considered as limiting the scope thereof, because the present disclosure may allow other equally effective embodiments.

[0011] Figure 1 A schematic diagram depicting a process chamber according to an example embodiment of the present disclosure.

[0012] Figure 2A A grounding assembly is depicted in a lowered position according to an example embodiment of the present disclosure.

[0013] Figure 2B A grounding assembly is depicted in a raised position according to an example embodiment of the present disclosure.

[0014] Figure 2C According to an example embodiment of the present disclosure, a grounding assembly and clamp are depicted prior to installation.

[0015] Figure 3A Depicted is a top view of an example bottom flange of a ground assembly according to an example embodiment of the present disclosure.

[0016] Figure 3B Depicted is a cross-sectional view of a bottom flange according to an example embodiment of the present disclosure.

[0017] Figure 4A Depicted is a top view of an example strip of a ground assembly according to an example embodiment of the present disclosure.

[0018] Figure 4B Depicted is the end of a strap secured in a bottom flange of a ground assembly according to an example embodiment of the present disclosure.

[0019] Figure 5A Depicted is a bottom view of an example top flange of a grounding assembly according to an example embodiment of the present disclosure.

[0020] Figure 5BDepicted is a top view of an example top flange of a grounding assembly according to an example embodiment of the present disclosure.

[0021] Figure 6 A flow chart depicts an example method of processing a substrate according to an example embodiment of the present disclosure.

[0022] 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. DETAILED DESCRIPTION

[0023] Embodiments presented herein are directed to radio frequency (RF) grounding in a process chamber. The process chamber includes a chamber body and a lid defining a volume therein. A substrate support is disposed in the volume, opposite the lid, and coupled to a grounding assembly. The substrate support includes a support body disposed on a backbone. The grounding assembly is coupled to a grounding plate disposed between the support body and the backbone. A top flange is coupled to a lower peripheral surface of the grounding plate, and a bottom flange is coupled to a bottom of the chamber body. The top flange and the bottom flange are coupled to each other by metal strips. Each of the strips is coupled to the bottom flange at a first end, and coupled to the top flange at a second end of each strip.

[0024] Figure 1 A schematic diagram of a process chamber 100 is depicted according to an example embodiment of the present disclosure. The process chamber 100 includes a chamber body 102 and a lid assembly 104 disposed on the chamber body 102. The chamber body 102 and the lid assembly 104 define an upper volume 110 and a lower volume 111 therein. A bottom 148 of the chamber body 102 faces the lid assembly 104. The lid assembly 104 includes a face plate 106 having a plurality of holes 134 formed therethrough for supplying gas from a gas source 130 coupled to the lid 104. Gas from the gas source 130 flows to a plenum 132 at least partially defined by the lid 104 and the face plate 106. The plenum 132 is in fluid communication with the upper volume 110 via the plurality of holes 134. The plurality of holes 134 formed through the face plate 106 enables substantially uniform distribution of gas into the upper volume 110. A power source 170 , such as an RF power source, is coupled to the substrate body 112 and is used to excite the gas from the gas source 130 within the upper volume 110 .

[0025] A channel 124 is formed through the lid 104. The channel 124 surrounds at least a portion of the upper volume 110. The channel 124 is in fluid communication with an exhaust pump (not shown). The channel 124 enables gases and particles to be removed from the upper volume 110 to avoid damage or contamination of the film deposited on the substrate. In certain embodiments, it is contemplated that the channel 124 may be formed in the sidewall of the chamber body 102 instead of first.

[0026] An opening 126 is formed through the chamber body 102 and enables a substrate to be loaded onto a supporting surface 150 of a substrate support 105 (eg, a susceptor) through the opening 126. The supporting surface 150 is substantially parallel to and faces the lid assembly 104.

[0027] The substrate support 105 is arranged in the process chamber 100. The substrate support 105 includes a support body 112, an insulating plate 122, a ground plate 146, and a backbone 108. The insulating plate 122 is positioned between the support body 112 and the ground plate 146, and is arranged together on the backbone 108. The insulating plate 122 is made of an electrically insulating material, such as a dielectric material or a ceramic, such as silicon oxide or aluminum oxide, to electrically insulate the substrate body 112 and the ground plate 146. The support body 112 can be a chuck, such as an electrostatic chuck or a vacuum chuck, and includes a bottom surface 156 facing the bottom 148 of the chamber body 102. In certain embodiments that can be combined with other embodiments described herein, the support body 112 is a single member. The backbone 108 extends laterally through the bottom 148 of the chamber body 102. The backbone 108 is substantially orthogonal to the bottom 148. The bottom 148 is substantially parallel to the face plate 106. The conductive bar 114 is disposed on and extends through the backbone 108 and is electrically coupled to the ground plate 146 .

[0028] The ground plate 146 is coupled to a grounding assembly 160. The grounding assembly 160 is coupled to the support body 112 via the ground plate 146 and the insulating plate 122. The ground plate 146 is made of a conductive material, such as a metal, such as aluminum, and is coupled to the insulating plate 122. The insulating plate 122 is coupled to a bottom surface 156 of the support body 112. Alternatively, the ground plate 146 and the insulating plate 122 include a central opening through which the backbone 108 is disposed, allowing contact between the backbone 108 and a central portion of the bottom surface 156. The support body divides the interior of the process chamber 100 into an upper (or process) volume 110 and a lower volume 111. The actuator 116 moves the substrate support 105 between an upper or elevated processing position and a lower loading position.

[0029] A ground assembly 160 including a plurality of straps 121 physically and electrically couples the ground plate 146 to the bottom 148 of the chamber body. The ground assembly 160 includes a top flange 118, a bottom flange 119, and a plurality of straps 121, such as resilient straps, extending therebetween. An RF return path is provided from the RF source 170 to the substrate body 112, traveling through the plasma in the upper volume 110, and back down along the chamber wall to the chamber bottom 148, to the ground plate 146, up to the straps 121, to the top flange 118, to the ground plate 146 and to ground via the conductive rods 114.

[0030] The top flange 118 of the grounding assembly 160 is arranged along the lower peripheral surface 142 of the grounding plate 146 and is fastened or adhered thereto using fasteners, welding, soldering or conductive paste. The top flange 118 is arranged in a plane substantially parallel to the support surface 150. The top flange 118 extends along the lower surface 142 of the grounding plate 146 to align with the radial outer surface 144 of the support body 112. The top flange 118 is in the shape of a ring and is made of a conductive material, such as metal, such as aluminum or steel, such as stainless steel. The top flange 118 is electrically coupled to the bottom flange 119 via a plurality of strips 121. The top flange 118 is configured to move with the substrate support body 112 between a lowered position and a raised position as the actuator 116 lowers and raises the support body 112. During actuation, the strips 121, for example, bend inward to accommodate the movement of the support body 112.

[0031] The bottom flange 119 is coupled to the bottom 148 of the chamber body. The bottom flange 119 is a ring that is axially aligned with the top flange 118. The top flange has an outer diameter that is substantially equal to the outer diameter of the support surface 150 and substantially equal to the outer diameter of the bottom flange 119. In one example, the bottom flange 119 and the top flange 118 have the same size. The bottom flange 119 is made of a conductive material, such as a metal, such as aluminum or stainless steel. The bottom flange 119 is fixed in position during the operation of the support body 112. The bottom flange 119 facilitates the flow of RF current away from the RF source. The RF current path is provided from the RF source 170 to the substrate body 112, travels through the plasma in the upper volume 110, and returns along the chamber wall down to the chamber bottom 148, to the ground plate 146, up to the strip 121, to the top flange 118, to the ground plate 146, and to ground via the conductive rod 114.

[0032] Figure 2A The grounding assembly 160 is depicted in a lowered position (eg, a compressed position), and Figure 2B The grounding assembly 160 is depicted in a raised position (eg, an extended position). In the lowered position, the strip 121 is Figure 2A In the raised position, the strip 121 is compressed radially inwardly as depicted. Figure 2B In the lowered position, the gap between the bottom surface of the top flange 118 and the top surface of the bottom flange 119 is large enough so that the screws on the top flange 118 do not contact the screws on the bottom flange 119.

[0033] Figure 2C The grounding assembly 160 is depicted prior to installation into the process chamber 100. The grounding assembly 160 is in a compressed position and the clamp 202 is disposed between the top flange 118 and the bottom flange 119. Figure 2CA single clamp 202 is depicted, there may be one or more clamps 202 disposed between the top flange 118 and the bottom flange 119. In certain embodiments, which may be combined with other embodiments described herein, there are about 1 to about 6 clamps, such as about 2 to about 4 clamps, such as about 3 clamps. The clamp 202 is secured in place between the top flange 118 and the bottom flange 119 by screws 204, such as stainless steel screws that run from the top surface of the top flange 118 through the clamp 202 and partially through the top portion of the bottom flange 119. The screws 204 are removed and during installation, the grounding assembly 160 is installed into the chamber with the clamp 202 in place. Once the top plate 118 is secured to the grounding plate 146, the clamp 202 is removed from the side between the top flange 118 and the bottom flange 119.

[0034] Figure 3A depicts a top view of the bottom flange 119 showing the top surface 317 of the bottom flange 119, and Figure 3B Describes an L-shaped cross-sectional view of the bottom flange 119. The bottom flange 119 is a ring, such as Figure 3A and 3B , which has an L-shaped cross-section. The first width 312 of the upper portion 324 of the bottom flange 119 including the top surface 317 is defined by the outer circumferential edge 305 and the first inner circumferential edge 303, each edge having a concentrically aligned surface. The first width 312 is about 20 mm to about 30 mm, for example, about 25 mm. The second width 314 of the lower portion 322 of the bottom flange 119 including the bottom surface 319 of the bottom flange 119 is defined by the outer circumferential edge 305 and the second inner circumferential edge 306, each edge having a concentrically aligned surface. The second width 314 is about 30 mm to about 40 mm, for example, about 35 mm. The second width 314 can be wider than the first width 312 from about 5% to about 30%, for example, about 5% to about 25%, for example, about 10% to about 20%.

[0035] The lower portion 322 of the bottom flange 119 has a first surface (e.g., the bottom surface 319 of the bottom flange) and a second surface 318, the second surface 318 being positioned parallel to the first surface 319 of the lower portion 322 of the bottom flange 119. The height 332 of the lower portion 322 of the bottom flange 119 is the distance between the first surface 319 and the second surface 318 of the lower portion 322 of the bottom flange 119. The height 332 of the lower portion 322 of the bottom flange 119 is about 4 mm to about 6 mm, such as about 4 to about 5 mm. The total height 334 of the bottom flange 119 is the distance between the first surface 319 of the bottom flange 119 and the top surface 317. The total height 334 of the bottom flange 119 is about 20 mm to about 50 mm, such as about 30 mm to about 45 mm, such as about 43 mm. The height 332 of the lower portion 322 is about 2% to about 30%, such as about 4% to about 20%, such as about 5% to 15%, of the total height 334 of the bottom flange 119. The height 332 of the bottom flange 119 is selected based on the space in the chamber where the grounding assembly 160 can be installed, such as to allow for the removal of the clamp 202. The outer diameter of the bottom flange 119 is sized to be substantially the same as the outer diameter of the substrate body 112 and the outer diameter of the top flange 118. In certain embodiments that may be combined with other embodiments described herein, the outer diameter of one or both of the bottom flange 119 and the top flange is about 300 mm to about 400 mm, such as about 350 mm to about 370 mm.

[0036] The second surface 318 of the lower portion 322 of the bottom flange 119 includes a plurality of openings 308 (four shown) disposed therethrough. The plurality of openings 308 are configured to receive fasteners 416 ( Figure 4B ) to couple the bottom flange 119 to the bottom 148 of the chamber body. In one example, each of the plurality of openings 308 is equally spaced at regular distances from one another. For example, when four openings 308 are utilized, the openings 308 are spaced about 90 degrees from one another. In certain embodiments that may be combined with other embodiments described herein, the angular spacing between each of the openings 308 around the bottom flange is from about 18 degrees to about 36 degrees, such as about to about 30 degrees. The openings 308 are arranged to be staggered with one or more lift pin drill rods so that the strips 121 do not physically contact the lift pin drill rods. The openings 308 are arranged to be staggered with the current supply holes in the chamber.

[0037] The top surface 317 of the bottom flange 119 includes a plurality of grooves 302 formed therein. Each groove 302 extends from an outer edge 305 to a radially inward edge 303 of the upper portion 24 of the bottom flange 119. The distance from the inner edge 303 to the outer edge 305 is about 20 mm to about 30 mm, for example about 25 mm. Each groove 302 is configured to receive a first end 410 of each strip 121 (see FIG. 4 ) and may extend to a depth equal to the thickness of each strip 121. The example strip 121 is Figure 4A . The strip 121 includes a first end 410, a second end 412, and at least one opening 414 disposed at each of the first and second ends 410, 412. During installation, the first end 410 is positioned within the groove 302 at the top surface 317 of the bottom flange 119. The opening 414 is aligned with the opening 304 formed in the groove 302. Figure 4B , the first end 410 of the strap 121 is fastened in the groove 302 with a fastener 416. In certain embodiments that may be combined with other embodiments described herein, the first end 410 of the strap 121 is fastened to the top surface 317 of the bottom flange 119 by welding or soldering. Each groove 302 is angularly offset from the opening 308, causing the opening 304 to also be angularly offset from the opening 308. In one example, each groove 302 is angularly equidistant from an adjacent opening 308. Although in Figure 3A The number of openings 304 is equal to the number of openings 308 , and it is contemplated that the number of openings 304 may be greater or less than the number of openings 308 .

[0038] Figure 5A A bottom view of the top flange 118 is depicted, showing the bottom surface 527 of the top flange 118. The bottom surface 527 of the top flange 118 is defined by an outer circumferential edge 525 and an inner circumferential edge 523, each edge having concentrically aligned surfaces. The distance from the outer circumferential edge 525 to the inner circumferential edge 523 is about 15 mm to about 30 mm, such as about 20 mm to about 25 mm. A plurality of grooves 522 are arranged on the bottom surface 527 of the top flange 118. The grooves 522 on the bottom surface 527 of the top flange 118 are aligned with the grooves 302 on the top surface 317 of the bottom flange 119. The second end 412 of the strip 121 (shown in Figure 4A118 in a manner substantially similar to that in which the first end 410 is fastened to the top surface 317 of the bottom flange 119. Specifically, the strap 121 is fastened by positioning the second end 412 in a groove 522 disposed on the top flange 118, aligning the opening 524 of the second end 412 of the strap 121 with the opening in the groove 522 disposed in the bottom surface 527 of the top flange 118, and fastening the second end of the strap 121 with the fastener 416. In certain embodiments, which may be combined with other embodiments described herein, the second end 412 of the strap 121 is fastened to the bottom surface 527 of the top flange 118 by welding or soldering.

[0039] The bottom surface 527 of the top flange 118 includes a plurality of openings 508 (four shown) disposed therethrough. The plurality of openings 508 are configured to receive fasteners 416 to couple the top flange 118 to the ground plate 142. In addition, at least one of the plurality of openings 508 is used to fasten the clamp 202 to the top flange using a screw 204. In certain embodiments that may be combined with other embodiments disclosed herein, each opening 508 of the plurality of openings 508 is equally spaced angularly from one another. In certain embodiments that may be combined with other embodiments disclosed herein, each recess 522 is angularly equidistant from an adjacent opening 508. Although in Figure 5A The number of openings 524 is equal to the number of openings 508, although it is contemplated that the number of openings 524 may be greater or less than the number of openings 508. Figure 3A and Figure 5A Each of the ground components 160 depicts four grooves (eg, 302, 522), the example ground component 160 may have four or more strips 121, such as about 10 to about 20, such as about 10 to about 16, such as about 12.

[0040] Figure 5B A top view of the top flange 118 is depicted, showing a top surface 502 of the top flange 118. The top surface 502 of the top flange 118 includes a channel 528 arranged around the top surface 502, separating an outer portion 532 of the top flange 118 from an inner portion 530 of the top flange 118. The channel 528 is configured to receive a gasket, such as a stainless steel gasket, to seal the top flange 118 to the ground plate 142. Sealing the top flange 118 prevents RF current from leaking in the lower volume 111. A plurality of openings 508 are arranged around the outer portion 532, and a plurality of openings 524 are arranged around the inner portion 530. The openings 524 are configured to receive the strap 121.

[0041] The fastener 416 is any suitable screw, such as a high nickel content stainless steel screw. The screw is made of a conductive material, such as an alloy, such as steel. In certain embodiments that may be combined with other embodiments disclosed herein, the screw does not contain copper. The strip 121 is made of a conductive material, such as an alloy, such as steel. The material of the strip 121 includes carbon, chromium, nickel, manganese, silicon, nitrogen, phosphorus, sulfur, stainless steel, Inconel material, alloys thereof, or combinations thereof. A plurality of strips 121 are symmetrically arranged around each of the top flange and the bottom flange to provide a symmetrical RF return path in the process chamber as depicted in the grounding assembly 160. It has been found that if the strips 121 are not sufficiently symmetrical, processing uniformity and device quality are affected. In certain embodiments that may be combined with other embodiments described herein, the angular spacing between each of the plurality of strips 121 around the bottom flange is from about 18 degrees to about 36 degrees, for example, about to about 30 degrees. In certain embodiments, which may be combined with other embodiments described herein, the angular spacing between two adjacent strips 121 varies by less than 5% relative to the remaining adjacent strips 121. The strips 121 are arranged to be staggered with one or more lift pin drill rods so that the strips 121 do not physically contact the lift pin drill rods.

[0042] The thickness of each strip 121 is about 0.12 mm to about 0.30 mm, such as about 0.15 mm to about 0.2 mm. The length of the strip 121 is about 180 mm to about 195 mm, such as about 180 mm to about 190 mm, such as about 195 mm. The width of the strip 121 is about 8 mm to about 15 mm, such as about 9 mm to about 11 mm, such as about 10 mm. The strip 121 has a spring constant greater than about 17 lb / in, such as about 17 lb / in to about 20 lb / in, such as about 18 lb / in to about 19 lb / in, such as about 18.4 lb / in to about 18.8 lb / in. Each strip is composed of stainless steel, such as SS302 or Inconel material. In certain embodiments that can be combined with other embodiments described herein, the material of the strip is any material that provides sufficient spring constant and corrosion resistance. In certain embodiments, which may be combined with other embodiments described herein, the strip undergoes from about 200,000 to 2 million mechanical cycles by bending the strip without exhibiting mechanical fatigue.

[0043] The grounding assembly 160 used herein is used during several operations without having to replace the strip 121. In contrast, previous grounding assemblies are usually replaced or maintained regularly because of the loss of spring constant over time. These grounding assemblies include designs that have grounding components that are only coupled to the ground plate at all times during processing. Furthermore, when the substrate body 112 is in the raised position during processing, the grounding component only contacts the seal of the substrate cover. During processing with these traditional grounding assemblies, the substrate body 112 is repeatedly raised and lowered, which relies on multiple compressions and expansions of the grounding component. The multiple compressions and expansions of the grounding component are attributed to excessive use resulting in a decrease in elasticity or spring constant over time, and the grounding component is regularly replaced. In contrast, the grounding assembly 160 described herein is coupled to the ground plate at all times during operation and is coupled to the bottom of the chamber at all times. Therefore, raising and lowering the substrate body 112 does not reduce the contact of the grounding assembly 160 to the chamber body. Furthermore, because the strip 121 of the present disclosure is secured at each end to the top flange 118 and the bottom flange 119, the strip 121 does not rely on its own spring constant to return to shape. Instead, actuation of the substrate support 105 returns the strip 121 to the desired position. Thus, the problem of reducing the spring constant, which is a problem in conventional solutions, is solved by the present disclosure.

[0044] Figure 6 A flow chart depicting an example method 600 of processing a substrate according to an example embodiment of the present disclosure. In operation 602, a substrate is positioned on a substrate support 105 in an upper volume 110 of a process chamber 100. The substrate is loaded through an opening 126 formed through the chamber body 102 and onto an upper surface 150 of a substrate support 105 (e.g., a pedestal). The substrate support 105 is coupled to an example grounding assembly 160 via a ground plate 146 described herein. Positioning the substrate on the substrate support includes positioning the substrate on the support body 112.

[0045] In operation 604 of method 600, the substrate support is raised to a raised position using the actuator 116. The substrate support is raised using the actuator 116. The grounding assembly 160 described herein enables the substrate support to be coupled to the bottom surface 148 of the chamber body in the raised position and in the lowered position. Thus, a grounding path is maintained at all times during operation and during various different processes performed at various substrate support positions (e.g., different substrate support heights). The processes described herein include operating conditions with a large gap between the top and bottom flanges. Grounding assemblies known in the art provide grounding for processes with a fixed gap, such as a narrow gap between the substrate body 112 and the bottom surface 148 of the chamber. The grounding assembly described herein provides a grounding path at all times during a number of different processes with different gaps between the substrate body 112 and the bottom surface 148 of the chamber. Constant grounding between the substrate body 112 and the bottom surface 148 of the chamber for different gaps allows for a wide process window. In certain embodiments that may be combined with other embodiments described herein, the gap between the substrate body 112 and the bottom surface 148 of the chamber is from about 6 mm to about 51 mm. Constant grounding as described in the present disclosure enables stable processing, such as during deposition of a film, or or additionally, during plasma cleaning of the chamber. Constant grounding as described in the present disclosure will reduce the risk of any asymmetric parasitic plasma established due to loose ground contact. Ground strap designs known in the art rely on spring constants to make full contact with the ground path, which is not reliable and often uses preventive maintenance. The ground strap can be fixed to one or more sides of the chamber. However, these arrangements are limited by the gap size between the substrate body 112 and the bottom surface 148 of the bottom chamber.

[0046] In operation 606 , gas is directed to the upper volume 110 . The gas is supplied from a gas source 130 coupled to the cover 104 and directed from the gas source 130 through the faceplate 106 into the upper volume 110 .

[0047] In operation 608, the gas is activated using electromagnetic energy, such as radio frequency energy, and a plasma is generated via capacitive coupling. The activated gas is used to deposit material on the substrate. The radio frequency allows an RF path from the substrate support through the plasma in the upper volume 110 to the bottom of the chamber body, through the ground assembly 160 to the ground plate 146, and through the conductive rod 114 to ground. The RF return path substantially reduces the occurrence of RF leakage, the formation of parasitic plasma, and arcing within the volumes 110 and 111 by providing a better path for RF travel. The term "parasitic plasma" as used herein refers to plasma in the volume outside of the upper volume 110. Specifically, the plasma established in the lower volume 111 of the volume is considered to be a "parasitic plasma". In certain embodiments that may be combined with other embodiments disclosed herein, the lower volume 111 includes a voltage of less than 100V in the gas of the lower volume 111. The voltage of less than 100V within the gas in the lower volume 111 is attributed to the grounding assembly 160 disclosed herein exhibiting minimized RF leakage into the lower volume 111. The grounding assembly 160 reduces the voltage of the gas in the lower volume 111 by providing an RF path from the substrate support 105 to ground and avoids RF leakage into the lower volume 111. The grounding assembly 160 of the present disclosure facilitates processing of substrates in plasma-assisted chemical vapor deposition, etching processes, or any process using an RF source provided to the bottom surface 156 of the substrate body 112.

[0048] Certain features, structures, components, materials or characteristics described herein may be combined in any suitable manner in one or more embodiments. Although the present disclosure has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the present disclosure. It will be apparent to those skilled in the art that various modifications and changes may be made to the methods and systems of the present disclosure. Therefore, the present disclosure is intended to include modifications and changes within the scope of the appended claims and their equivalents.

Claims

1. A device comprising: a chamber body and a cover defining a volume therein; a substrate support disposed in the volume opposite to the cover, the substrate support comprising: a support body arranged on the trunk, the support body being configured to be coupled to a radio frequency source, the radio frequency source being fed through the trunk; a ground plate coupled to ground and arranged between the support body and the backbone; and an insulating plate disposed between the support body and the ground plate, the insulating plate at least partially providing electrical insulation between the support body and the ground plate; a circular top flange coupled to a lower peripheral surface of the ground plate, wherein the circular top flange includes a central opening disposed through the circular top flange for providing access to an RF supply feedthrough; a circular bottom flange coupled to the bottom of the chamber body; and A plurality of strips, each of which includes a first end coupled to the circular bottom flange and a second end coupled to the circular top flange, provide a radio frequency path from the bottom of the chamber body to the ground plate connected to ground.

2. The device of claim 1, wherein the plurality of strips comprises 10 to 20 strips.

3. The device of claim 1, wherein each of the plurality of strips is composed of a metal comprising stainless steel, Inconel, carbon, chromium, nickel, manganese, silicon, nitrogen, phosphorus, sulfur, or combinations thereof.

4. The device of claim 1 , wherein the first end of each of the plurality of strips is coupled to a groove portion of the top surface of the circular bottom flange using a screw, and the second end of each strip is coupled to a groove portion of the bottom surface of the circular top flange using a screw.

5. The device of claim 1, wherein the circular top flange comprises a metal comprising steel, aluminum, alloys thereof, or combinations thereof.

6. The apparatus of claim 1, wherein the circular bottom flange is coupled to the bottom of the chamber using a plurality of stainless steel fasteners.

7. The apparatus of claim 1, wherein each of the plurality of strips is configured to bend radially inward when the substrate support is in a retracted position.

8. The device of claim 1 wherein each strap comprises a spring constant from 17 lb / in to 20 lb / in.

9. The device of claim 1, wherein a minimum distance between the circular top flange and the circular bottom flange is greater than 6 mm.

10. The apparatus of claim 1, further comprising a conductive rod configured to be coupled to a ground and extending through the backbone, capable of providing a radio frequency path from the ground plane to the ground.

11. A method for processing a substrate, comprising the following steps: positioning a substrate on a substrate support in a volume formed by chamber walls, a lid, and a bottom of a processing chamber, the substrate support being arranged in the volume opposite the lid, the substrate support comprising a support body arranged on a backbone, an insulating plate arranged between the support body and the ground plate, and a circular top flange coupled to a lower peripheral surface of the ground plate, the insulating plate at least partially providing electrical insulation between the support body and the ground plate, the processing chamber comprising a circular bottom flange coupled to the bottom of the chamber and a plurality of strips, each of the strips comprising a first end coupled to the circular bottom flange and a second end coupled to the circular top flange; raising the substrate support to a raised position to form an upper portion of the volume; introducing a gas into said upper portion of said volume; and The gas is activated using RF energy supplied to the substrate body, the RF energy flowing from the substrate body to the activated gas in the volume of the processing chamber, to the bottom of the chamber, along the plurality of strips and up to the ground plate, wherein the circular bottom flange includes a central opening disposed through the circular bottom flange for providing access to an RF supply feedthrough.

12. The method of claim 11, wherein the lower portion of the volume is free of plasma.

13. The method of claim 11, wherein the substrate is processed in a plasma enhanced chemical vapor deposition or etching process.

14. The method of claim 11, wherein the step of raising the substrate support to a raised position comprises the step of raising the ground plate and maintaining a radio frequency path from the circular bottom flange through at least one of the plurality of strips to the ground plate.

15. A system comprising an algorithm, the algorithm being stored in a memory of the system, wherein the algorithm comprises a plurality of instructions which, when executed by a processor, cause the method of claim 11 to be performed.

16. An apparatus comprising: a circular top flange, comprising a top flange upper surface and a top flange lower surface; a circular bottom flange comprising a bottom flange upper surface and a bottom flange lower surface, the circular bottom flange comprising a lower portion extending radially inwardly from an inner diameter of the circular bottom flange, the lower portion comprising one or more openings configured to receive screws; and A plurality of straps, each of the straps comprising a first end coupled to the circular bottom flange and a second end coupled to the circular top flange, each of the plurality of straps being symmetrically positioned about the circular top flange and capable of bending radially inwardly to a center of the circular top flange, wherein each strap comprises a spring constant from 17 lb / in to 20 lb / in.

17. The apparatus of claim 16, wherein the top flange lower surface comprises a groove configured to receive the second end of each of the plurality of straps, and the bottom flange upper surface comprises a groove configured to receive the first end of each of the plurality of straps.

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