Movable edge ring with reduced capacitance variation for substrate processing systems

Abstract

A movable edge ring system for a plasma processing system includes: a top edge ring; and a first edge ring disposed below the top edge ring. The second edge ring is made of an electrically conductive material and includes an upper portion, an intermediate portion, and a lower portion. The top edge ring and the second edge ring are configured to move in a vertical direction relative to a substrate support and the first edge ring when upwardly offset by a lift pin. The second edge ring is disposed below the top edge ring and radially outward of the first edge ring.

Description

This application is a continuation of application No. 202080056085.9, filed on August 4, 2020, for the inventor patent application entitled “MOVABLE EDGE RING FOR SUBSTRATE PROCESSING SYSTEM WITH REDUCED CAPACITANCE VARIATION” and assigned to Lam Research Corporation. Cross Reference to Related Applications

[0001] This application claims the benefit of U.S. Provisional Application No. 62 / 976,088, filed on February 13, 2020, and U.S. Provisional Application No. 62 / 882,890, filed on August 5, 2019. The entire disclosures of the above-referenced applications are hereby incorporated by reference. TECHNICAL FIELD

[0002] The present disclosure relates generally to plasma processing systems, and more specifically to edge ring systems with movable edge rings. BACKGROUND

[0003] The background description provided here is for the purposes of generally presenting the context of the disclosure. The work of the presently-named inventors in this regard, as well as aspects of the description that can not otherwise qualify as prior art at the time of filing of this application, are neither expressly nor impliedly admitted as prior art against the present disclosure.

[0004] Substrate processing systems perform processing on substrates, such as semiconductor wafers. Examples of substrate processing include deposition, ashing, etching, cleaning, and / or other processing. A mixture of process gases can be supplied to a processing chamber to process a substrate. A plasma can be used to ignite the gases to enhance chemical reactions.

[0005] During processing, a substrate is disposed on a substrate support. An edge ring is annular and disposed around and adjacent to a radially outer edge of the substrate. The edge ring can be used to shape or focus plasma onto the substrate. During operation, exposed surfaces of the substrate and edge ring are etched by the plasma. Thus, the edge ring wears, and the effect of the edge ring on the plasma changes over time. SUMMARY

[0006] A movable edge ring system for a plasma processing system includes a top edge ring and a first edge ring disposed below the top edge ring. A second edge ring is made of an electrically conductive material and includes an upper portion, a middle portion, and a lower portion. The top edge ring and the second edge ring are configured to move in a vertical direction relative to a substrate support and the first edge ring when biased upward by a lift pin. The second edge ring is disposed below the top edge ring and radially outward of the first edge ring.

[0007] In other features, the lower portion of the second edge ring extends radially inward relative to the middle portion to define a first gap between the lower portion of the second edge ring and a radially outer surface of the substrate support. The middle portion of the second edge ring defines a second gap between the middle portion and the radially outer surface of the substrate support. The second gap is greater than or equal to twice the first gap.

[0008] In other features, the middle portion of the second edge ring moves parallel to a radially outer edge of the first edge ring when the lift pins raise the second edge ring and the top edge ring. The top edge ring has an inverted "U" shape. The top edge ring is made of a conductive material. The top edge ring is made of a dielectric material. The first edge ring is made of a conductive material. The first edge ring is made of a dielectric material. The middle portion of the second edge ring extends radially inward relative to the upper portion of the second edge ring to define a first annular recess.

[0009] In other features, the first edge ring includes a second annular recess on a radially outer surface thereof. Radially inner feet of the top edge ring are positioned in the first and second annular recesses when the top edge ring is in a lowered position.

[0010] In other features, a third edge ring is positioned below and radially outward of the first edge ring, the second edge ring, and the top edge ring. The third edge ring defines an annular recess on an upper radially inner surface thereof. Radially outer feet of the top edge ring are positioned in the annular recess when the top edge ring is in a lowered position.

[0011] In other features, the third edge ring includes a vertical aperture to accommodate the lift pins. The second edge ring has a generally rectangular cross-section and a radially inner surface parallel to a radially outer edge of the substrate support.

[0012] A moveable edge ring system for a plasma processing system includes a top edge ring. A first edge ring is made of a dielectric material and includes an embedded conductor that is fully embedded within the dielectric material. The first edge ring is positioned below the top edge ring. The top edge ring and the first edge ring are configured to move in a vertical direction relative to a substrate support when being offset upward by a lift pin.

[0013] In other features, a second edge ring is positioned below the top edge ring. The first edge ring includes an upper portion, a middle portion, and a lower portion. The first edge ring is positioned below the top edge ring and radially outward of the second edge ring.

[0014] In other features, the lower portion of the first edge ring extends radially inward relative to the middle portion and defines a first gap between the lower portion of the second edge ring and a radially outer surface of the substrate support. The middle portion of the first edge ring defines a second gap between the middle portion and the radially outer surface of the substrate support. The second gap is greater than or equal to twice the first gap.

[0015] In other features, the middle portion of the first edge ring moves parallel to a radially outer edge of the second edge ring when the lift pins raise the first edge ring and the top edge ring. The top edge ring has an inverted "U" shape.

[0016] In other features, the embedded conductor includes a horizontal conductor disposed in the upper portion parallel to an upper surface of the first edge ring. The embedded conductor also includes a vertical conductor disposed in the lower portion parallel to a radially inner surface of the first edge ring. The embedded conductor also includes a conductor connecting the vertical conductor and the horizontal conductor. The top edge ring is made of a conductive material. The top edge ring is made of a dielectric material. The second edge ring is made of a dielectric material. The second edge ring is made of a conductive material.

[0017] In other features, a third edge ring is located below and radially outward of the first edge ring, the second edge ring, and the top edge ring. The third edge ring defines an annular recess on an upper radially inner surface. A radially outer leg of the top edge ring is located in the annular recess when the top edge ring is in a lowered position. The third edge ring includes a vertical hole to accommodate the lift pin.

[0018] In other features, the first edge ring is made of a ceramic green sheet that includes conductive traces and vias.

[0019] A movable edge ring system for a plasma processing system includes a top edge ring. A first edge ring is made of a dielectric material and includes a doped region and an undoped region. The doped region is more conductive than the undoped region. The first edge ring is located below the top edge ring. The top edge ring and the first edge ring are configured to move in a vertical direction relative to a substrate support when biased upward by a lift pin.

[0020] In other features, a second edge ring is disposed below the top edge ring. The first edge ring includes an upper portion, a middle portion, and a lower portion. The first edge ring is disposed below the top edge ring and radially outward of the second edge ring.

[0021] In other features, the lower portion of the first edge ring extends radially inward relative to the middle portion and defines a first gap between the lower portion of the second edge ring and a radially outer surface of the substrate support. The middle portion of the first edge ring defines a second gap between the middle portion and the radially outer surface of the substrate support. The second gap is greater than or equal to twice the first gap.

[0022] In other features, the middle portion of the first edge ring moves parallel to a radially outer edge of the second edge ring when the lift pin raises the first edge ring and the top edge ring. A doped region is disposed along an upper surface and a radially inner surface of the first edge ring. The top edge ring has an inverted "U" shape. The top edge ring is made of a conductive material. The top edge ring is made of a dielectric material. The second edge ring is made of a conductive material. The second edge ring is made of a dielectric material.

[0023] In other features, a third edge ring is located below and radially outward of the first edge ring, the second edge ring, and the top edge ring. The third edge ring defines an annular recess on an upper radially inner surface. A radially outer leg of the top edge ring is located in the annular recess when the top edge ring is in a lowered position. The third edge ring includes a vertical hole to accommodate the lift pin.

[0024] An edge ring for a plasma processing system includes an annular body made of at least one of a dielectric material and a conductive material. The annular body includes an upper portion, a middle portion, and a lower portion. A first step projects radially outward from a radially inner surface of the annular body between the upper portion and the middle portion. A second step projects radially outward from the radially inner surface of the annular body between the middle portion and the lower portion.

[0025] In other features, the annular body is made of a dielectric material and further includes an embedded conductor disposed entirely inside the annular body. The embedded conductor includes a horizontal conductor disposed in the upper portion parallel to an upper outer surface of the annular body. The embedded conductor also includes a vertical conductor disposed in the lower portion of the annular body parallel to a radially inner surface of the annular body. The embedded conductor also includes a conductor connecting the vertical conductor and the horizontal conductor. The annular body is made of a dielectric material and further includes a doped region and an undoped region. The doped region is more conductive than the undoped region. The doped region is disposed on an upper surface and a radially inner surface of the annular body. The annular body is made of a ceramic green sheet that includes a conductive trace and a via.

[0026] An edge ring for a plasma processing system includes an annular body made of a dielectric material and configured to surround a substrate support of the plasma processing system. An embedded conductor is disposed entirely inside the annular body and includes a first conductor disposed within the annular body and a second conductor disposed within the annular body transverse to and connected to the first conductor.

[0027] In other features, the annular body has an "L" shaped cross-section. The annular body includes a first leg connected to a second leg. The first conductor is disposed in the first leg and the second conductor is disposed in the second leg.

[0028] In other features, the first conductor is disposed parallel to a first outer surface of the annular body. The third conductor is disposed parallel to a second outer surface of the annular body. The second conductor connects the first conductor to the third conductor. The annular body includes an upper portion, an intermediate portion, and a lower portion. A first step is located on a radially inner surface of the annular body between the upper portion and the intermediate portion and projects radially outwardly therefrom. A second step is located on the radially inner surface of the annular body between the intermediate portion and the lower portion and projects radially outwardly therefrom.

[0029] In other features, the first conductor is disposed parallel to a first outer surface of the annular body at the upper portion. The second conductor is disposed parallel to a radially inner surface of the annular body at the lower portion. The third conductor connects the first conductor to the second conductor. The annular body is made of a ceramic green sheet that includes a conductive trace and a via.

[0030] An edge ring for a plasma processing system includes an annular body configured to surround a substrate support of the plasma processing system. An embedded conductor is disposed within the annular body and is configured to be capacitively coupled to, but not directly coupled to, at least one external conductive component selected from the group consisting of a base plate of the substrate support and another edge ring.

[0031] An edge ring for a plasma processing system includes an annular body made of a dielectric material and configured to be disposed around a substrate support. The annular body includes a doped region and an undoped region. The doped region is more conductive than the undoped region.

[0032] In other features, the doped region includes a first portion disposed along a radially inner surface of the annular body. The doped region includes a second portion disposed on an upper surface of the annular body. The first portion is in contact with the second portion. The annular body includes an upper portion, an intermediate portion, and a lower portion. A first step is located on a radially inner surface of the annular body between the upper portion and the intermediate portion and projects radially outwardly therefrom. A second step is located on the radially inner surface of the annular body between the intermediate portion and the lower portion and projects radially outwardly therefrom.

[0033] In other features, the dielectric material includes silicon carbide. The dielectric material is doped with an impurity selected from the group consisting of boron, aluminum, or nitrogen.

[0034] A movable edge ring system for a plasma processing system includes a top edge ring. A first edge ring is disposed below the top edge ring and has a rectangular cross-section. A second edge ring is made of an electrically conductive material, has a Z-shaped cross-section, and is disposed radially outward and above the first edge ring. The top edge ring and the second edge ring are configured to move vertically relative to the first edge ring and a substrate support when being offset by a lift pin.

[0035] In other features, when the second edge ring is moved upward along the first edge ring from a lowered position to a raised position, the second edge ring maintains a fixed surface area within a predetermined gap of a radially outer surface of the first edge ring. A remaining surface area of the second edge ring is located at a distance greater than or equal to twice the predetermined gap from the first edge ring.

[0036] In other features, the second edge ring includes a ring body including an upper portion projecting radially inward; a middle portion extending in a vertical direction and connected to the upper portion; a lower portion connected to a lower end of the middle portion and projecting radially outward; and a projection extending radially inward from the middle portion and downward to a lower edge of the lower portion.

[0037] In other features, the fixed surface area is defined by the projection. A third edge ring is located below the top edge ring and radially inward of the first edge ring. The third edge ring has an "L"-shaped cross-section. A fourth edge ring is located radially outward of the top edge ring and the second edge ring. The fourth edge ring includes a projection extending radially inward and disposed between the top edge ring and a portion of the second edge ring. The top edge ring has an inverted "U"-shape, a main body, an inner leg, and an outer leg. In the lowered position, the top edge ring is proximate to the second edge ring, the third edge ring, and the fourth edge ring.

[0038] In other features, the top edge ring is made of an electrically conductive material. The top edge ring is made of a dielectric material. The first edge ring is made of an electrically conductive material.

[0039] A movable edge ring system for a plasma processing system includes a first edge ring made of an electrically conductive material and configured to surround a substrate support. A lift pin is made of an electrically conductive material. A lift pin actuator is configured to offset the lift pin against the first edge ring in a lowered position and selectively move the lift pin to increase a height of the first edge ring relative to the substrate support and maintain contact between the lift pin and the first edge ring.

[0040] In other features, a second edge ring is located radially inward and below the first edge ring. The second edge ring is made of a dielectric material. The second edge ring has an "L"-shaped cross-section and includes a radially inner leg extending in a vertical direction and a radially outer leg extending in a horizontal direction.

[0041] In other features, the third edge ring is located radially outward of and below the first edge ring and the second edge ring. The third edge ring is made of a dielectric material. The third edge ring has an "L" shaped cross section. The first edge ring has a rectangular cross section.

[0042] In other features, the third edge ring includes a ring body; and a radially inward protrusion including a vertical hole to accommodate a lift pin.

[0043] A movable edge ring system for a plasma processing system includes a first edge ring made of a dielectric material and including an embedded conductor disposed entirely inside the dielectric material and configured to surround a substrate support. A lift pin is made of an electrically conductive material. A lift pin actuator is configured to bias the lift pin against the first edge ring when in a lowered position and selectively move the lift pin to increase a height of the first edge ring relative to the substrate support and maintain contact between the lift pin and the first edge ring.

[0044] In other features, the embedded conductor includes a first horizontal conductor disposed parallel to a top surface of the first edge ring. A second horizontal conductor is disposed parallel to a bottom surface of the first edge ring. A third conductor connects the first horizontal conductor to the second horizontal conductor.

[0045] In other features, the second edge ring is located radially inward of and below the first edge ring. The second edge ring is made of a dielectric material. The second edge ring has an "L" shaped cross section and includes a radially inner leg extending in a vertical direction and a radially outer leg extending in a horizontal direction.

[0046] In other features, the third edge ring is located radially outward of and below the first edge ring and the second edge ring. The third edge ring is made of a dielectric material. The third edge ring has an "L" shaped cross section. The first edge ring has a rectangular cross section. The third edge ring includes a ring body; and a radially inward protrusion including a vertical hole to accommodate a lift pin.

[0047] A movable edge ring system for a plasma processing system includes a top edge ring having an inverted "U" shaped cross section and including a ring body, a radially inner leg, and a radially outer leg. A first edge ring is made of an electrically conductive material and is disposed at least partially between the radially inner leg and the radially outer leg of the top edge ring. A second edge ring is made of a dielectric material and is disposed between the first edge ring and a substrate support. A third edge ring is disposed below and radially outward of the first edge ring and the second edge ring and includes N cavities to accommodate N lift pins, where N is an integer greater than 2. The top edge ring is moved relative to the first edge ring, the second edge ring, the third edge ring, and the substrate support when biased by the N lift pins.

[0048] In other features, the second and third edge rings are made of a dielectric material. The first edge ring has an "L" shaped cross-section. The second edge ring has an "L" shaped cross-section. The top edge ring includes N radial recesses spaced 360 / N apart on a radially inner surface of the radially outer leg and includes a beveled lower surface extending radially outward from the radial recesses. The N lift pins offset the top edge ring in the N radial recesses when adjusting a height of the top edge ring.

[0049] An edge ring for a plasma processing system includes an annular body having an inverted "U" shaped cross-section. A radially inner leg extends from the annular body. A radially outer leg extends from the annular body. N radial recesses spaced 360° / N apart are on a radially inner surface of the radially outer leg, where N is an integer greater than 2, and includes a beveled lower surface extending radially outward from the N radial recesses.

[0050] A movable edge ring system includes an edge ring. A first edge ring has a "U" shaped cross-section and includes an annular body, a radially inner leg, and a radially outer leg. The radially inner leg of the edge ring is between the radially inner leg and the radially outer leg of the first edge ring. A second edge ring is disposed below and radially outward of the edge ring and the first edge ring and includes N vertical holes to accommodate N lift pins. The edge ring moves relative to the first edge ring, the second edge ring, and a substrate support when offset by the N lift pins.

[0051] In other features, the first and second edge rings are made of a dielectric material. The first edge ring has an "L" shaped cross-section. The second edge ring has an "L" shaped cross-section. The edge ring is configured to accommodate N lift pins in N radial recesses when adjusting a height of the edge ring.

[0052] A movable edge ring system includes an edge ring. A first edge ring has an "L" shaped cross-section and includes a radially inner leg and a vertical leg. The vertical leg of the first edge ring is between the radially inner leg and a radially outer leg of the edge ring. A second edge ring is disposed radially inward of the first edge ring. A third edge ring is disposed below and radially outward of the edge ring. The first and second edge rings include vertical holes to accommodate a lift pin. The edge ring moves relative to the first edge ring, the second edge ring, the third edge ring, and a substrate support when offset by the lift pin.

[0053] A movable edge ring system for a plasma processing system includes a top edge ring having an inverted "U" shaped cross section and including an annular body, a radially inner leg, and a radially outer leg. A first edge ring is made of a dielectric material and includes an embedded conductor disposed entirely within the dielectric material and configured to surround a substrate support and at least partially disposed between the radially inner leg and the radially outer leg of the top edge ring. A second edge ring is made of a dielectric material and disposed between the substrate support and the first edge ring. A third edge ring is disposed below and radially outward of the first edge ring and the second edge ring and includes a vertical aperture to accommodate a lift pin. The top edge ring is movable relative to the first edge ring, the second edge ring, and the third edge ring when offset by the lift pin.

[0054] In other features, the second edge ring and the third edge ring are made of a dielectric material. The second edge ring has an "L" shaped cross section. The first edge ring has an "L" shaped cross section. The first edge ring includes an annular body having a vertical leg connected to a horizontal leg. The embedded conductor includes a vertical conductor disposed in the vertical leg and a horizontal conductor disposed in the horizontal leg in communication with the vertical conductor.

[0055] An edge ring for a plasma processing system includes an annular body, a radially inner leg connected to the annular body, and a radially outer leg connected to the annular body. A first portion of an upper surface of the annular body is parallel to a plane that includes a substrate. A second portion of the upper surface of the annular body is inclined downward at an acute angle from the first portion.

[0056] In other features, the first portion of the upper surface is located radially inward of the second portion of the upper surface. A third portion of the upper surface is parallel to the plane that includes the substrate and is located radially outward of the second portion of the upper surface.

[0057] A movable edge ring system includes an edge ring. A first edge ring is made of a conductive material and configured to surround a substrate support and at least partially disposed between a radially inner leg and a radially outer leg of the edge ring.

[0058] In other features, a second edge ring is made of a dielectric material and disposed between the first edge ring and the substrate support. A third edge ring is disposed below and radially outward of the first edge ring and the second edge ring and includes a vertical aperture to accommodate a lift pin. The edge ring is movable relative to the first edge ring, the second edge ring, and the substrate support when offset by the lift pin.

[0059] An edge ring for a plasma processing system includes an annular body having a rectangular cross section. A radially inwardly projecting leg extends from a radially inner and upper surface of the annular body. A radially inner portion of the upper surface of the annular body is disposed parallel to a plane that includes a substrate.

[0060] In other features, a radially outer portion of the upper surface of the annular body slopes downward at an acute angle from a radially inner portion.

[0061] A movable edge ring system for a plasma processing system includes an edge ring. An intermediate edge ring is disposed below radially inward projecting legs and radially inward of an annular body. An outer edge ring is disposed below the edge ring and the intermediate edge ring and includes a vertical aperture to accommodate a lift pin. The edge ring moves vertically relative to the intermediate edge ring and the outer edge ring when offset by the lift pin.

[0062] In other features, the intermediate edge ring has a generally rectangular cross-section and an annular recess on a radially inner and upper surface thereof. A substrate is disposed in the annular recess. The outer edge ring includes a radially outer portion and an inner portion extending radially inward from a middle portion of the radially outer portion.

[0063] In other features, the outer edge ring includes a protrusion on an upper radially inner surface of the inner portion. The protrusion is adjacent to a junction between a heating plate of a substrate support and a substrate. A bottom of the annular body is located adjacent to an upper surface of the outer edge ring between the radially outer portion and the protrusion.

[0064] A plasma processing system includes a movable edge ring system. A substrate support includes a base plate. A heating plate is joined to the base plate. The heating plate includes a main body including a plurality of radio frequency (RF) electrodes, a cylindrical portion, and a protrusion extending radially outward below an intermediate edge ring from the cylindrical portion.

[0065] In other features, the plurality of RF electrodes are not located in a portion of the protrusion that is located below the intermediate edge ring.

[0066] A movable edge ring system for a plasma processing system includes a top edge ring configured to surround a substrate support. The movable edge ring system includes an annular body; a radially outer leg projecting downward from a radially outer surface of the annular body; a radially inner leg projecting downward from a radially inner surface of the annular body; and an inward projecting leg extending radially inward from a lower end of the radially inner leg. The inward projecting leg is disposed below a substrate when the substrate is disposed on the substrate support. A first edge ring is configured to surround the substrate support and is disposed below the top edge ring and includes an annular body and radially inward projecting legs. An upper surface of the first edge ring is disposed between a radially inner leg and a radially outer leg of the top edge ring when the first edge ring is offset against the top edge ring.

[0067] In other features, a second edge ring is disposed radially outward of the top edge ring and the first edge ring. The second edge ring includes an annular body; a radially outward projecting leg extending from an upper radially outer surface of the annular body; and a radially inward projecting leg extending radially inward from a radially inner and lower surface of the annular body.

[0068] In other features, the inwardly projecting leg of the first edge ring extends radially inwardly from an upper radial inner surface of the annular body of the first edge ring. A third edge ring is disposed radially outward of the first edge ring and below the top edge ring, the first edge ring, and the second edge ring. The third edge ring includes an annular body; a radially downwardly projecting leg extending from a radially outer lower surface of the third edge ring; and an inwardly projecting leg extending radially inwardly from a middle portion of the third edge ring.

[0069] In other features, the inwardly projecting leg of the third edge ring includes a vertical hole to accommodate the lift pin. The first edge ring defines a first vertical gap between a lower surface of the radially inner leg of the first edge ring and a surface of the substrate support; and a second vertical gap between a lower surface of the first edge ring and an upper surface of the inwardly projecting leg of the third edge ring when offset against the top edge ring.

[0070] In other features, the first edge ring abuts the inward leg of the third edge ring and the projection defines a third vertical gap between an upper surface of the first edge ring and a lower surface of the top edge ring when in the lowered position.

[0071] A plasma processing system includes a process chamber. A substrate support is disposed in the process chamber. The process chamber includes a substrate port. A robot arm delivers a substrate onto the substrate support. A movable edge ring system is disposed around the substrate support. A lift pin offsets a top edge ring and a first edge ring relative to the substrate support.

[0072] In other features, the first edge ring and the top edge ring are raised relative to the substrate support by the lift pin, the robot arm removes the top edge ring, and the robot arm delivers another top edge ring to the substrate support through the substrate port.

[0073] An edge ring system for a plasma processing system includes an upper ring including a first annular body configured to surround a substrate support during plasma processing. A lower ring includes a second annular body configured to surround the substrate support during plasma processing. At least a portion of the second annular body of the lower ring nests into a portion of the first annular body of the upper ring to define a predetermined gap relative to the portion when configured for plasma processing. N spacers are disposed in N spaced locations on a surface of at least one of the upper ring and the lower ring to reduce variation in the predetermined gap between the annular body of the upper ring and the annular body of the lower ring when heating and cooling the upper ring and the lower ring during plasma processing, where N is an integer greater than or equal to 3 and less than or equal to 8.

[0074] In other features, at least one of the N spacers includes a shim seated in a slot on a radially opposite surface of at least one of the upper and lower rings. The shim has a rectangular cross-section. The slot is on a radially outer surface of the inner ring. At least one of the N spacers includes a pin seated in a slot on a surface of at least one of the upper and lower rings. The slot is on a radially outer surface of the inner ring. The N spacers are arranged at intervals of 360° / N.

[0075] In other features, at least one of the N spacers includes a protrusion formed on a surface of at least one of the upper and lower rings. The protrusion is on a radially outer surface of the inner ring. A coating covers the protrusion. The coating includes an insulating material.

[0076] In other features, the coating is selected from the group consisting of polytetrafluoroethylene (PTFE), perfluoroalkoxy polymer (PFA), aluminum oxide deposited using atomic layer deposition, yttrium oxide deposited using atomic layer deposition, and yttrium fluoride deposited using atomic layer deposition. In other features, N = 5. The lift pins raise the upper ring relative to the lower ring to adjust a height of a top surface of the upper edge ring relative to a substrate on the substrate support.

[0077] An edge ring for a plasma processing system includes a first annular body configured to surround a substrate support during plasma processing. At least a portion of the first annular body is configured to nest in a portion of a second annular body of an upper ring exposed to plasma during plasma processing and define a predetermined gap relative to the portion. N spacers are arranged in N spaced locations on at least one of a radially inner surface and a radially outer surface of the annular bodies to reduce variation in the predetermined gap when heating and cooling the upper and lower rings during plasma processing, where N is an integer greater than or equal to 3 and less than or equal to 7.

[0078] In other features, at least one of the N spacers includes a shim seated in a slot on at least one of the radially inner and outer surfaces of the annular body. The shim has a rectangular cross-section. The slot is on a radially outer surface of the first annular body. At least one of the N spacers includes a pin seated in a slot on at least one of the radially inner and outer surfaces of the first annular body. The slot is on a radially outer surface of the first annular body.

[0079] In other features, the N spacers are arranged at intervals of 360° / N. At least one of the N spacers includes a protrusion formed on at least one of a radially inner surface and a radially outer surface of the first annular body. The protrusion is on the radially outer surface of the inner ring. The coating covers the protrusion. The coating includes an insulating material. The coating is selected from the group consisting of polytetrafluoroethylene (PTFE), perfluoroalkoxy polymer (PFA), aluminum oxide deposited using atomic layer deposition, yttrium oxide deposited using atomic layer deposition, and yttrium fluoride deposited using atomic layer deposition. In other features, N = 5.

[0080] Other ranges of applicability of the present disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0081] The present disclosure will become more fully understood from the detailed description and drawings, wherein:

[0082] FIG. 1A is a functional block diagram of an example of a substrate processing system according to the present disclosure;

[0083] FIG. 1B and 1C is a cross-sectional view of an example of a moveable edge ring according to the present disclosure;

[0084] FIG. 2 is a functional block diagram of another example of a substrate processing system according to the present disclosure;

[0085] FIG. 3A is a cross-sectional side view of an example of a moveable edge ring according to the present disclosure;

[0086] FIG. 3B is a simulation FIG. 3A of an electrical schematic of a moveable edge ring;

[0087] FIG. 4 is a cross-sectional side view of another example of a moveable edge ring according to the present disclosure;

[0088] FIG. 5A and FIG. 5B is a diagram showing movement of different surfaces of a moveable edge ring relative to adjacent structures;

[0089] FIG. 6A to FIG. 6D is a cross-sectional side view of another example of a moveable edge ring according to the present disclosure;

[0090] FIG. 7A to FIG. 7B is a cross-sectional side view of another example of a moveable edge ring according to the present disclosure;

[0091] FIG. 8A to FIG. 8CCross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0092] FIG. 9A to FIG. 9C Cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0093] FIG. 9C1 Partial bottom view of a portion of a top edge ring according to the present disclosure;

[0094] FIG. 9C2 Cross-sectional view of a portion of a top edge ring according to the present disclosure;

[0095] FIG. 9D to FIG. 9G Cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0096] FIG. 10A and FIG. 10B Cross-sectional side view of another example of a movable edge ring including embedded conductors according to the present disclosure;

[0097] FIG. 11A and 11B Cross-sectional side view of another example of a movable edge ring including embedded conductors according to the present disclosure;

[0098] FIG. 11C to FIG. 11E Cross-sectional view of an example of a movable edge ring and embedded conductors according to the present disclosure;

[0099] FIG. 12A and FIG. 12B Cross-sectional side view of another example of a movable edge ring including embedded conductors according to the present disclosure;

[0100] FIG. 13A and FIG. 13B Cross-sectional side view of another example of a movable edge ring including doped conductive portions according to the present disclosure;

[0101] FIG. 14A to FIG. 14C Cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0102] FIG. 15 Cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0103] FIG. 16A to FIG. 16D Cross-sectional side view of other examples of movable edge rings according to the present disclosure;

[0104] FIG. 17 Cross-sectional view of a portion of an upper and lower edge ring according to the present disclosure;

[0105] FIG. 18To show a plot of capacitance increase as a function of percent deviation from a nominal gap according to the present disclosure;

[0106] FIG. 19 To show a side cross-sectional view of an edge ring system including an upper ring and a lower ring according to the present disclosure;

[0107] FIG. 20 To show a side cross-sectional view of an edge ring system including an upper ring and a lower ring according to the present disclosure;

[0108] FIG. 21 To show a side cross-sectional view of an edge ring system including an upper ring and a lower ring according to the present disclosure;

[0109] FIG. 22A To show a side cross-sectional view of an edge ring system including an upper ring and a lower ring according to the present disclosure; and

[0110] FIG. 22B To show a magnified side cross-sectional view of a lower edge ring according to the present disclosure including a protrusion having a convex flat.

[0111] In the drawings, reference numerals can be repeated among the figures for like and / or identical elements. DETAILED DESCRIPTION

[0112] During substrate processing, a substrate is arranged on a susceptor, such as an electrostatic chuck (ESC), process gases are supplied, and a plasma is excited in a processing chamber. Exposed surfaces of components in the processing chamber are subject to wear due to the plasma.

[0113] For example, an edge ring is arranged to surround a radially outer edge of a substrate to shape the plasma. After processing a substrate, the exposed surfaces of the edge ring are worn and are at different heights relative to the substrate. As a result, the effect of the edge ring on the plasma changes, which alters the effect of the processing on the substrate. To reduce the processing variations due to edge ring wear without breaking vacuum, some processing chambers raise the height of the edge ring to compensate for the wear. In many of these systems, the height of the edge ring is automatically adjusted based on the number of cycles and / or total plasma processing exposure time. Other systems, however, measure the height of the edge ring and adjust the height based on the measured height.

[0114] When the height of the edge ring is adjusted, the capacitive coupling between the plasma, sheath, and / or the capacitive transfer structure, including the edge ring, changes. These changes in capacitive coupling can cause non-uniformities in substrate processing over time. Various edge ring arrangements according to the present disclosure significantly reduce the capacitive changes in the transfer structure due to changes in the height of the edge ring.

[0115] More specifically, a plasma sheath is created between the plasma and the transfer component. In some examples, an RF bias is output to the substrate support. To maintain control of the sheath at low RF bias frequencies (e.g., less than 5 MHz or less than 1 MHz) to ensure process uniformity, the capacitance value of the transfer component to the substrate support needs to be maintained when adjusting the height of the edge ring to compensate for wear. The area of the edge ring and / or nearby structures that are capacitively coupled are designed to minimize the change in capacitively coupling as the top edge ring is moved. In some examples, the capacitance is minimized in separate areas that move as the height of the edge ring is increased. The capacitance is controlled in other surface areas that do not change (or change less) as the height of the edge ring is increased.

[0116] In some examples, the edge ring is made of a conductive material. As used herein, a conductive material refers to a material having an electrical resistivity less than or equal to 10 4 Ωcm. For example, doped silicon has an electrical resistivity of 0.05 Ωcm, silicon carbide has an electrical resistivity of 1-300 Ωcm, and metals (e.g., aluminum and copper) have an electrical resistivity of ~10 - 7 Ωcm. In other examples, the edge ring is made of a non-conductive or dielectric material (electrical resistivity > 10 4 Ωcm) with embedded conductive electrodes. The embedded electrodes are designed to minimize the change in capacitively coupling as the top edge ring is moved. In other examples, the edge ring is made of a dielectric material and includes doped regions that are more conductive than the undoped regions. The doped regions are designed to minimize the change in capacitively coupling as the edge ring is moved to compensate for wear.

[0117] Reference is now made to FIG. 1A and FIG. 2 which show examples of plasma processing chambers using a movable edge ring. As can be appreciated, other types of plasma processing chambers can be used. In FIG. 1A , which shows an example of a substrate processing system 110 according to the present disclosure. The substrate processing system 110 can be used to perform etching using capacitively coupled plasma (CCP). The substrate processing system 110 includes a processing chamber 122 that encloses other components of the substrate processing system 110 and contains the RF plasma (if used). The substrate processing system 110 includes an upper electrode 124 and a substrate support 126, such as an electrostatic chuck (ESC). During operation, a substrate 128 is disposed on the substrate support 126.

[0118] By way of example only, the upper electrode 124 can include a gas distribution device 129, such as a showerhead, that introduces and distributes a process gas. The gas distribution device 129 can include a stem portion that includes one end connected to a top surface of the processing chamber. An annular body is generally cylindrical and extends radially outward from an opposite end of the stem portion at a location spaced apart from the top surface of the processing chamber. A substrate-facing surface or faceplate of the annular body of the showerhead includes a plurality of holes through which a precursor, reactant, etching gas, inert gas, carrier gas, other process gas, or purge gas flows. Alternatively, the upper electrode 124 can include a conductive plate and the process gas can be introduced in another manner.

[0119] The substrate support 126 includes a base plate 130 that serves as a lower electrode. The base plate 130 supports a heating plate 132, which can correspond to a ceramic multi-zone heating plate. A bonding and / or thermal resistance layer 134 can be disposed between the heating plate 132 and the base plate 130. The base plate 130 can include one or more channels 136 to flow a coolant through the base plate 130.

[0120] An RF generation system 140 generates and outputs an RF voltage to one of the upper electrode 124 and a lower electrode, such as the base plate 130 of the substrate support 126. The other of the upper electrode 124 and the base plate 130 can be DC grounded, AC grounded, or floating. By way of example only, the RF generation system 140 can include an RF generator 142 that generates RF plasma power that is fed to the upper electrode 124 or the base plate 130 by a matching and distribution network 144. In other examples, the plasma can be inductively or remotely generated.

[0121] A gas delivery system 150 includes one or more gas sources 152-1, 152-2, …, and 152-N (collectively, gas sources 152), where N is an integer greater than zero. The gas sources 152 are connected to a manifold 160 by valves 154-1, 154-2, …, and 154-N (collectively, valves 154) and mass flow controllers (MFCs) 156-1, 156-2, …, and 156-N (collectively, MFCs 156). Auxiliary valves can be used between the MFCs 156 and the manifold 160. Although a single gas delivery system 150 is shown, two or more gas delivery systems can be used.

[0122] A temperature controller 163 can be connected to a plurality of thermal control elements (TCEs) 164 disposed in the heating plate 132. The temperature controller 163 can be used to control the plurality of TCEs 164 to control the temperature of the substrate support 126 and the substrate 128. The temperature controller 163 can be in communication with a coolant assembly 166 to control the flow of coolant through the passages 136. For example, the coolant assembly 166 can include a coolant pump, a reservoir, and / or one or more temperature sensors. The temperature controller 163 operates the coolant assembly 166 to selectively flow coolant through the passages 136 to cool the substrate support 126.

[0123] The valve 170 and the pump 172 can be used to evacuate reactants from the processing chamber 122. A system controller 180 can be used to control components of the substrate processing system 110. During plasma processing, an edge ring 182 can be disposed radially outward of the substrate 128. An edge ring height adjustment system 184 can be used to adjust the height of a top surface of the edge ring 182 relative to the substrate 128, as will be further described below. In some examples, the edge ring 182 can also be raised, removed by the robot end effector, and replaced with another edge ring without breaking vacuum.

[0124] Referring now to FIG. 1B and FIG. 1C In some examples, the substrate 128 is located on an upper surface 190 of the substrate support 126 (or ESC). In FIG. 1B In some examples, the edge ring 182 is located on the intermediate edge ring 186 and the bottom edge ring 188. The intermediate edge ring 186 and the bottom edge ring 188 do not move. When the edge ring 182 is located on the intermediate edge ring 186 and the bottom edge ring 188 and the edge ring 182 is not worn, the edge ring 182 defines a height h above the upper surface 190. One or more openings 192 can be defined in one or more of the substrate support 126, the intermediate edge ring 186, and / or the bottom edge ring 188 to enable the height adjustment to adjust the height of the edge ring 182, as will be further described below.

[0125] In some examples, the edge ring 182 is located on the intermediate edge ring 186 and the bottom edge ring 188. The intermediate edge ring 186 and the bottom edge ring 188 do not move. When the edge ring 182 is located on the intermediate edge ring 186 and the bottom edge ring 188 and the edge ring 182 is not worn, the edge ring 182 defines a height h above the upper surface 190. One or more openings 192 can be defined in one or more of the substrate support 126, the intermediate edge ring 186, and / or the bottom edge ring 188 to enable the height adjustment to adjust the height of the edge ring 182, as will be further described below. FIG. 1C In some examples, the edge ring 182 is located on the intermediate edge ring 186 and the bottom edge ring 188. The intermediate edge ring 186 and the bottom edge ring 188 do not move. When the edge ring 182 is located on the intermediate edge ring 186 and the bottom edge ring 188 and the edge ring 182 is not worn, the edge ring 182 defines a height h above the upper surface 190. One or more openings 192 can be defined in one or more of the substrate support 126, the intermediate edge ring 186, and / or the bottom edge ring 188 to enable the height adjustment to adjust the height of the edge ring 182, as will be further described below.

[0126] FIG. 2 ​An example of a substrate processing system 210 according to this disclosure is shown. The substrate processing system 210 uses inductively coupled plasma to perform etching. The substrate processing system 210 includes a coil drive circuit 211. A pulse circuit 214 can be used to pulse-on and pulse-off RF power or to change the amplitude or level of the RF power. A tuning circuit 213 can be directly connected to one or more induction coils 216. The tuning circuit 213 tunes the output of the RF source 212 to a desired frequency and / or desired phase, matches the impedance of the coils 216, and distributes power among the coils 216. In some examples, in conjunction with controlling the RF bias, the coil drive circuit 211 is replaced by one of the drive circuits further described below.

[0127] In some examples, a gas chamber 220 may be arranged between coil 216 and dielectric window 224 to control the temperature of dielectric window 224 using hot and / or cold airflow. Dielectric window 224 is arranged along one side of processing chamber 228. Processing chamber 228 also includes a substrate support (or base) 232. Substrate support 232 may include an electrostatic chuck (ESC), a mechanical chuck, or other type of chuck. Process gas is supplied to processing chamber 228, and plasma 240 is generated inside processing chamber 228. Plasma 240 etches the exposed surfaces of substrate 234. Drive circuitry 252 (e.g., one of the drivers described below) may be used to provide RF bias to electrodes in substrate support 232 during operation.

[0128] A gas delivery system 256 can be used to supply a process gas mixture to a process chamber 228. The gas delivery system 256 may include a process and inert gas source 257, a gas metering system 258 (e.g., valves and mass flow controllers), and a manifold 259. A gas delivery system 260 can be used to deliver gas 262 to a gas chamber 220 via a valve 261. The gas may include cooling gas (air) for cooling coil 216 and dielectric window 224. A heater / cooler 264 can be used to heat / cool substrate support 232 to a predetermined temperature. A purging system 265 includes a valve 266 and a pump 267 to remove reactants from the process chamber 228 by purging or evacuation.

[0129] A controller 254 can be used to control the etching process. The controller 254 monitors system parameters and controls the delivery of the gas mixture, the excitation, the sustaining and extinguishing of the plasma, the removal of reactants, the supply of cooling gases, etc. In addition, the controller 254 can control various aspects of the coil drive circuit 211 and the drive circuit 252, as described in detail below. During plasma processing, an edge ring 282 can be positioned radially outward of the substrate 234. A height adjustment system 284 can be used to adjust the height of the top surface of the edge ring 282. In addition, the edge ring 282 can be optionally removed and replaced with a new edge ring when worn without breaking vacuum. The controller 254 can be used to control the height adjustment system 284.

[0130] During processing, a plasma is excited in the processing chamber. In some examples, an RF bias is output to the substrate support. To maintain control of the plasma sheath layer at low bias frequencies, the capacitance C D In the following examples, the edge rings are made of a conductive material with embedded electrodes or a dielectric material. As will be further described below, the regions of capacitive coupling are designed to minimize the change in capacitive coupling as the top edge ring is moved.

[0131] Referring now to FIG. 3A An edge ring system for a substrate support includes a top edge ring 310, a middle edge ring 314, and a bottom edge ring 316. The top edge ring 310 has an inverted "U" shape and includes a ring body 330 connected to a radially inner leg 332 and a radially outer leg 334. The middle edge ring 314 has a "U" shape and includes a ring body 340 connected to a radially inner leg 342 and a radially outer leg 344. The radially inner leg 332 of the top edge ring 310 is positioned between the radially inner leg 342 and the radially outer leg 344 of the middle edge ring 314.

[0132] The bottom edge ring 316 includes a radially outer portion 350, a middle portion 352, and a radially inner portion 354. A ring-shaped recess 360 is disposed on an upper radially inner surface of the bottom edge ring 316 between the radially outer portion 350 and the middle portion 352. A ring-shaped recess 364 is disposed on an upper radially inner surface of the bottom edge ring 316 between the radially inner portion 354 and the middle portion 352. The bottom edge ring 316 includes an elongated vertical hole 374 configured to receive a lift pin 372 for raising and lowering the top edge ring 310. Likewise, the substrate 130 can include an elongated vertical hole 376 configured to receive the lift pin 372 and aligned with the elongated vertical hole 370. Although a single lift pin is shown, N lift pins can be used, where N is an integer greater than 2. In some examples, the N lift pins are spaced apart by an angle equal to 360 / N.

[0133] During operation, plasma 380 is generated. Sheath 390 is formed between plasma 380 and a transport component 392 (including top edge ring 310, middle edge ring 314, and / or bottom edge ring 316).

[0134] Referring now to FIG. 3B which shows an electrical model of the plasma, sheath, and transport component 392. Sheath 390 has a sheath capacitance C s and transport component 392 has a transport capacitance C D If the capacitance of transport component 392 changes in response to component wear or edge ring height adjustment, the processing will be less uniform, and performance variations and / or defects can occur.

[0135] Referring now to FIG. 4 Various parameters can be adjusted to change the capacitance of the transport component. In FIG. 4 top edge ring 420 has an inverted "U" shape and includes a radially inner leg 422 connected to a radially outer leg 426 by a ring body 424. Middle edge ring 430 has a "U" shape and includes a radially inner leg 438 connected to a radially outer leg 432 by a ring body 436. Radially inner leg 422 of top edge ring 420 is disposed between radially inner leg 438 and radially outer leg 432 of middle edge ring 430. Electrostatic electrode 410 and RF electrode 412 of substrate 130 are shown.

[0136] Bottom edge ring 440 includes a middle portion 444, an upper portion 446 (which projects upwardly from middle portion 444 adjacent to a radially outer edge of bottom edge ring 440), and a lower portion 448 (which projects downwardly from middle portion 444 adjacent to a radially outer edge of bottom edge ring 440). Bottom edge ring 440 includes a radially inner portion 450 having an upward projection 452 on an upper radially inner surface thereof. Substrate 130 includes a step portion 456 that accommodates radially inner portion 450 of bottom edge ring 440. Cavities 462 and 464 in bottom edge ring 440 and substrate 130, respectively, accommodate lift pins 470.

[0137] In some examples, top edge ring 420 and middle edge ring 430 are made of an electrically conductive material, while bottom edge ring 440 is made of a non-conductive material (e.g., a dielectric). In some examples, lift pins 470 are made of an electrically conductive or non-conductive material (e.g., a dielectric).

[0138] Referring now to FIG. 5A and FIG. 5B As the gap between opposing surfaces increases, the coupling capacitance between two conductive surfaces decreases significantly. As the edge ring is raised, the opposing surfaces in region A generally maintain the same gap D AConversely, as the edge ring is raised, the gap D B increases proportionally. The coupling capacitance of the opposing conductive surfaces will be influenced by both the A-zone and the B-zone. The A-zone will have a stable coupling capacitance as the edge ring moves, while the B-zone will have a decreasing coupling capacitance as the edge ring moves.

[0139] According to the present disclosure, the coupling capacitance in the A-zone is maximized due to its relative constancy, while the coupling capacitance in the B-zone is minimized due to its variability. In some examples, the gap D A in the A-zone is set to a minimum value, while the gap D B in the B-zone is set to k*D A , where k is a number greater than or equal to 2. In some examples, k is equal to 3. In some examples, for regions where coupling is desired, the gap is set to a gap less than or equal to 0.006" or 6 mils, while for regions where coupling is not desired, the gap is set to a gap greater than or equal to 0.012" or 12 mils. In some examples, for regions where coupling is desired, the gap is set to a gap less than or equal to 0.006" or 6 mils, while for regions where coupling is not desired, the gap is set to a gap greater than or equal to 0.018" or 18 mils.

[0140] In FIG. 5A and FIG. 5B , the opposing surfaces of the edge ring body during movement are shown. In the A-zone, the opposing surfaces of the edge ring slide adjacent to each other without significantly changing the gap D A between them. In the B-zone, the opposing surfaces of the edge ring slide apart and increase the gap D B between them.

[0141] In some examples, the gap D A is set based on the minimum gap (d min ) between the opposing surfaces in the A-zone. The minimum gap d min is determined based on the tolerances and / or thermal expansion of the transfer components for a given processing temperature range. The gap D A is set equal to the minimum gap d min in the A-zone where the capacitance is to remain constant. In other zones where the capacitance is to be minimized (due to the increasing gap between the opposing surfaces), the gap D B is set to be greater than or equal to k*d min , where k is a number greater than or equal to 2. In other examples, k is greater than or equal to 3. Thus, the capacitance from the A-zone dominates the transfer capacitance, while the capacitance from the B-zone has a significantly reduced impact on the transfer capacitance.

[0142] Reference is now made to FIG. 6A and FIG. 6BThe edge ring 610 has a "U" shape and includes an inner leg 612 connected to an outer leg 616 by an annular body 614. A recess 618 is located between the inner leg 612 and the outer leg 616. The top edge ring 620 has an inverted "U" shape and includes an inner leg 622 connected to an outer leg 626 by an annular body 624.

[0143] The edge ring 630 includes a radially inward projecting upper portion 632 connected to a radially outward projecting portion 636 by an intermediate portion 634. In some examples, the edge ring 630 has a "Z" shaped cross-section. A projecting surface 638 extends radially inwardly and downwardly (toward an opposing surface 639 of the edge ring 640) from an intermediate region of the intermediate portion 634 to a lower edge of the edge ring 630.

[0144] The edge ring 640 is positioned radially inwardly from the edge ring 630 and below the upper portion 632 of the edge ring 630. The edge ring 640 includes a main body 642 having a generally rectangular cross-section, an upper portion 644, a lower portion 646, and a projecting portion 648 that projects downwardly from a radially inner surface of the lower portion of the edge ring 640. The outer edge ring 650 includes a main body 652, a radially inward projecting portion 654 that projects radially inwardly adjacent to an upper surface of the main body 652, and a downward projecting portion 656 that projects downwardly from a radially outer surface of the outer edge ring 650. Annular recesses 658 and 659 provide clearance for the radially outward projecting portion 636 and the substrate 130, respectively.

[0145] An annular seal 660 is disposed in an annular groove 661 defined between the substrate 130, the heating layer 132, and the edge ring 640 to protect the bond and / or thermal resistance layer 134 disposed between the heating layer 132 and the substrate 130. Lift pins 662 pass through guide sleeves 664 disposed in vertical holes 666 in the substrate 130.

[0146] The top edge ring 620 is disposed on the edge ring 630. The inner leg 622 of the top edge ring 620 is located between the inner leg 612 of the edge ring 610 and the radially inward projecting upper portion 632 of the edge ring 630. The edge ring 610 is disposed on the stepped surface of the heating layer 132. The edge ring 640 is located radially outward of the heating layer 132 and the edge ring 610. The main body 652 of the outer edge ring 650 is located radially outward of the edge ring 630. The inward projecting portion 654 of the outer edge ring 650 is disposed between the outer leg 626 of the top edge ring 620 and the radially outward projecting portion 636 of the edge ring 630. A vertical gap 690 is defined between the edge ring 630 and the edge ring 610. A horizontal gap 691 is defined between the upper portions of the edge rings 630 and 640. A vertical gap is defined between the edge ring 630 and the outer edge ring 650.

[0147] In some examples, the edge ring 610 is disposed on the stepped surface of the heating layer 132. The edge ring 640 is located radially outward of the heating layer 132 and the edge ring 610. The main body 652 of the outer edge ring 650 is located radially outward of the edge ring 630. The inward projecting portion 654 of the outer edge ring 650 is disposed between the outer leg 626 of the top edge ring 620 and the radially outward projecting portion 636 of the edge ring 630. A vertical gap 690 is defined between the edge ring 630 and the edge ring 610. A horizontal gap 691 is defined between the upper portions of the edge rings 630 and 640. A vertical gap is defined between the edge ring 630 and the outer edge ring 650. FIG. 6BWhen the top edge ring 620 wears, the lift pins 662 move upward to offset the edge ring 630 upward to compensate for wear of the top edge ring 620 due to exposure to the plasma and / or other process gas mixtures. As can be seen, the protrusions 638 are disposed within a gap D A of the annular body. Likewise, the top surface of the edge ring 630 is disposed within a gap D A of the annular body. A minimum gap between the lower portions of the edge rings 630 and 640 is maintained to maintain a constant capacitive coupling. Other increasing gaps start at a larger gap (> twice the minimum gap) and then increase to reduce the impact on the capacitive coupling. Decreasing gaps start at and remain greater than twice the minimum gap to reduce the impact on the capacitive coupling.

[0148] Reference is now made to FIG. 6C which shows an exemplary variation of the edge ring 630. The upper portion 632 of the edge ring 630' extends down adjacent to the upper surface of the outer leg 616 of the edge ring 610 and adjacent to the upper surface of the upper portion 644 of the edge ring 640. The inner surface 637 of the edge ring 630 extends parallel to (and within a predetermined fixed distance of) the radially outer surface 641 of the edge ring 630. In some examples, the base height (e.g., the top surface of the top edge ring to the top surface of the heating layer 132) is in the range of 1 mm to 6 mm. In some examples, the base height is 4 mm. In some examples, the gap between the bottom surfaces of the upper portion 632 of the edge ring 630' is in the range of 0.1 mm to 1 mm. In some examples, the gap between the bottom surfaces of the upper portion 632 of the edge ring 630' is in the range of 0.1 mm to 0.5 mm. Increasing the gap then reduces the coupling therebetween, and vice versa.

[0149] In some examples, the top edge ring 620 is made of quartz, the edge ring 630' is made of silicon or silicon carbide, the edge ring 610 is made of quartz, and the edge ring 640 is made of silicon or silicon carbide, although other materials can be used.

[0150] Reference is now made to FIG. 6D which shows other variations of the edge ring 630" and the top edge ring 620'. The upper portion 632 of the edge ring 630' extends less radially inward relative to the edge rings 630 and 630' shown above. The inner leg 622 of the top edge ring 620' is wider (and extends further radially outward) in the radial direction.

[0151] In some examples, the top edge ring 620 is made of quartz, the edge ring 630" is made of silicon or silicon carbide, the edge ring 610 is made of quartz, and the edge ring 640 is made of silicon or silicon carbide, although other materials can be used.

[0152] Reference is now made to FIG. 7A and7B The top edge ring 710 has a rectangular cross-section. The middle edge ring 720 is "L" shaped and includes a vertical leg 722 connected to a radially outwardly projecting leg 726. The bottom edge ring 740 includes an annular body 744, an upward projection 742, a downward projection 749, and an inward projection 745.

[0153] The vertical hole 746 passes through the inward projection 745 to allow the lift pin 754 to pass through and move the top edge ring 710 accordingly. The inward projection 745 includes an upward projection 747 located adjacent to the pin 754 to define an annular recess to accommodate the outwardly projecting leg 726. The inward projection 745 also includes a downward projection 748 located adjacent to the radially inner surface of the bottom edge ring 740. The guide sleeve 750 is located in the annular recess defined by the downward projection 748.

[0154] In some examples, the top edge ring 710 and the lift pin 754 are made of an electrically conductive material. The middle edge ring 720 and the bottom edge ring 740 are electrically non-conductive and made of a dielectric material. In FIG. 7B The top edge ring 710 is raised, the capacitive coupling is maintained by the lift pin 754, which is electrically conductive and in contact with the top edge ring 710.

[0155] Reference is now made to FIG. 8A and FIG. 8B The top edge ring 810 has an inverted "U" shape and includes an annular body 812 connected to an inner leg 814 and an outer leg 816. The outer edge ring 820 includes a middle portion 822, a lower portion 824, and an upper portion 828. The middle portion 822 projects radially inward below the upper portion 828 to form an annular recess 826 or step to accommodate the outer leg 816 of the top edge ring 810 when the top edge ring 810 is lowered. The lower portion 824 projects radially inward toward the substrate 130 to form a step 829.

[0156] The edge ring 840 is located below the top edge ring 810 and between the outer edge ring 820 and the substrate 130. The edge ring 840 includes a middle portion 842, an upper portion 843, and a lower portion 844. The edge ring 840 extends radially inward to form an annular recess 846 or step between the middle portion 842 and the upper portion 843. The edge ring 840 extends radially inward to form an annular recess 848 or step between the middle portion 842 and the lower portion 844. The edge ring 840 includes a lower surface 849 located within the gap D A between the opposing surfaces of the substrate 130. Other surfaces of the edge ring 840 that face the substrate 130 and change as the edge ring 840 moves (as shown in FIG. 8B ) are located within the gap D B between the opposing surfaces of the substrate 130.

[0157] The edge ring 850 includes a main body portion 852 having a generally rectangular cross-section. An annular recess or step portion 854 is located radially outward of the main body portion 852. The inner leg of the top edge ring 810 is located in the annular recesses 846 and 854.

[0158] In some examples, the top edge ring 810 is made of an electrically conductive or dielectric material, the edge ring 850 and the outer edge ring 820 are made of a dielectric material, and the edge ring 840 is made of an electrically conductive material. Although the lift pins 870 are shown passing through vertical holes in the edge ring 820, the substrate 130 can further extend radially outward, and the lift pins can pass through the substrate 130 rather than the edge ring 820. In some examples, the radially inward facing opposing surfaces of the lower portion 844 and the middle portion 842 are parallel to the radially outward facing opposing surfaces of the substrate 130.

[0159] When the top edge ring 810 and the edge ring 840 are raised and lowered, the first surface area of the lower portion 844 of the edge ring 840 near (and facing) the substrate 130 remains the same. The second surface area of the middle portion 842 of the edge ring 840 (located further from the substrate 130) decreases as the edge ring is raised (because the edge ring 850 is located therebetween).

[0160] Referring now to FIG. 8C , the edge ring 870 has a generally rectangular cross-section, an upper portion 872 and a lower portion 874. An annular seal 876 is disposed around the upper surface of the substrate 130 radially outward of the bond and / or thermal resistance layer 134 beneath the heater plate 132. The edge ring 880 has an "L" shaped cross-section, and is located between the edge ring 870 and the heater plate 132. An annular recess 882 or step portion is disposed on the radially inner surface of the edge ring 880.

[0161] The top edge ring 884 has an inverted "U" shape, an annular body 885, a radially inner leg 886 and a radially outer leg 888. The outer edge ring 892 has a generally rectangular cross-section, and is disposed radially outward of the edge rings 870 and 884. The outer edge ring 892 has a generally rectangular cross-section, a radially inner upper annular recess 894 or step portion to accommodate the radially outer leg 888, and a radially inner lower annular recess 896 or step portion to accommodate the lower radially outer portion of the substrate 130.

[0162] Referring now to FIG. 9A and FIG. 9BThe top edge ring 910 has an inverted "U" shape and includes an annular body 912, an inner leg 914, and an outer leg 916. In some examples, the outer leg 916 is P times thicker than the inner leg 914 in the radial direction, where P is greater than or equal to 2 and less than or equal to 5. The edge ring 920 is generally "L" shaped and includes an upper leg 922 and a radially inner leg 924. The edge ring 930 is generally "L" shaped and includes an upper leg 932 and a radially outer leg 934, the radial outer side of the radially outer leg 934 adjacent to the radial inner side of the radially inner leg 924 of the edge ring 920.

[0163] The bottom edge ring 940 includes a middle portion 942. An upward portion 944 extends from the radially outer upper surface of the bottom edge ring 940. A downward portion 948 extends from the radially outer lower surface of the bottom edge ring 940. A radially inner portion 946 of the bottom edge ring extends radially inward below the outer support 916 of the top edge ring 910 and a portion of the edge ring 920. An upward protrusion 949 extends upward a predetermined distance from the radially inner surface of the radially inner portion 946.

[0164] In some examples, edge ring 920 and top edge ring 910 are made of conductive material. In some examples, edge rings 930 and 940 are made of dielectric material.

[0165] When the top edge ring is fully lowered, the outer support 916 of the top edge ring 910 extends below the lowermost surface of the edge ring 920 by a predetermined distance. Therefore, when the top edge ring 910 is raised, the relative surfaces of the top edge ring 910 and the edge ring 920 remain relatively identical. In some examples, this predetermined distance is greater than or equal to the maximum height increase of the top edge ring 910 due to wear.

[0166] For reference FIG. 9C The top edge ring 950 has an inverted "U" shape and includes an annular body 954, a radially inner support 952, and a radially outer support 956. In some examples, the radially outer support 956 is P times thicker than the radially inner support 952 in the radial direction. The top edge ring 950 includes a radial recess 957 located on the downwardly opposing surface of the radially outer support 956. An additional radial recess 957 is provided for each lifting pin. In some examples, three lifting pins are arranged around the edge ring and spaced apart at 120° intervals. The radial recess 957 includes a chamfered lower surface 958 that slopes downward at an acute angle and radially outward. The radial recess 957 and the chamfered lower surface 958 are offset by the lifting pins and help to center the top edge ring 950 relative to the substrate 130 and the substrate 128.

[0167] exist FIG. 9C1 and FIG. 9C2 An additional view of the radial recess is shown in the image. FIG. 9C1In some examples, a bottom view of a portion of the edge ring is shown. In FIG. 9C2 In some examples, a cross-sectional view taken along FIG. 9C1 In some examples, surfaces 990 and 992 have a radius. In some examples, angle Θ is in a range of 75° to 105° (e.g., 90°).

[0168] Edge ring 960 is generally "U" shaped and includes an annular body 966, a radially inner leg 962, and a radially outer leg 964. Radially inner leg 952 of top edge ring 950 is positioned between radially inner leg 962 and radially outer leg 964 of edge ring 960.

[0169] Edge ring 970 includes an annular recess 974 on a radially inner upper surface thereof. A radially inner portion 972 of edge ring 970 is arranged adjacent to substrate 130 and heater plate 132. Lift pins pass through vertical holes in radially inner portion 972 of edge ring 970. Radially inner portion 972 of edge ring 970 includes an annular recess 973 on a radially inner upper surface thereof to provide clearance and / or support for a lower portion of radially outer leg 964 of edge ring 960. Radially inner portion 972 of edge ring 970 also includes a protrusion 975 extending downward from a lower radially inner surface thereof.

[0170] In some examples, substrate 130 includes a conformal seal 971 that conforms to a stepped or lower radially outer surface of substrate 130. In some examples, conformal seal 971 is made of a material such as ceramic and reduces arcing. A lower surface of edge ring 970 includes a first annular recess 976 or step for accommodating lift pins and a second annular recess 978 for accommodating substrate 130.

[0171] In some examples, the base height is 3.5 mm. In some examples, edge rings 950 and 980 are made of an electrically conductive material such as silicon or silicon carbide, although other materials can be used. In other examples, edge rings 970 and 986 are made of quartz, although other materials can be used.

[0172] Referring now to FIG. 9D , an example of a variation of the edge ring system in FIG. 9C is shown. Edge ring 980 is positioned below top edge ring 950. Edge ring 980 is generally "L" shaped and includes a radially inwardly projecting leg 984 and a vertical leg 982. Vertical leg 982 is positioned between radially inner leg 952 and radially outer leg 956 of top edge ring 950. Edge ring 986 is positioned below substrate 128 and radially outward of heater plate 132. Edge ring 986 is generally rectangular with an annular recess 988 or step on a lower outer surface thereof to accommodate radially inwardly projecting leg 984.

[0173] In some examples, the base height (e.g., top surface of top edge ring 950 to top surface of substrate 130) is 3.5 mm. In some examples, edge rings 950, 980, 986, and 970 are made of quartz, silicon carbide, silicon (or silicon carbide), and quartz, respectively, although other materials can be used.

[0174] Referring now to FIG. 9E , other example variations of edge ring systems are shown. In FIG. 9E , the radially outer leg 956 of top edge ring 950' extends less radially outward and is covered by edge ring 990. Edge ring 990 has an "L" shaped cross-section and includes a radially inward projecting leg 992 and a downward projecting leg 994 connected to the radially outer portion of radially inward projecting leg 992. In some examples, edge ring 990 is made of silicon carbide, although other materials can be used. FIG. 9D Top edge ring 950 of FIG. 9E may be too large to fit through a substrate port into a processing chamber. Splitting top edge ring 950 into two parts, as in 950' and 990 of FIG. 9D , allows edge ring 990 to be removed and replaced through a substrate port (without breaking vacuum when using a vacuum transfer module). In some cases, edge ring 950 of may be too thick and / or heavy to be moved by a robot arm. By using a thinner and lighter top edge ring 990 in combination with edge ring 950", which is less thick and lighter, edge ring 990 can be removed as it wears.

[0175] In some examples, the base height (e.g., top surface of top edge ring 950 to top surface of substrate 130) is 3.5 mm. In some examples, edge rings 990, 950, and 980 are made of silicon carbide, edge ring 986 is made of silicon, and edge ring 970 is made of quartz, although other materials can be used.

[0176] Referring now to FIG. 9F , other example variations of edge ring systems are shown. In FIG. 9C , edge ring 950' is similar to top edge ring 950 of and has tighter tolerances. In some examples, the gap between edge rings is greater than 0.01 mm and less than or equal to 0.5 mm, 0.25 mm, 0.2 mm, or 0.1 mm. In other examples, the gap between the top edge ring and the substrate is greater than 100 pm and less than 500 pm, 400 pm, or 350 pm. In some examples, the base height (e.g., top surface of top edge ring 950' to top surface of substrate 130) is 5.5 mm. In some examples, edge rings 950', 980, and 970 are made of quartz, although other materials can be used.

[0177] FIG. 9G Referring now toThe outer edge ring 995 defines an annular recess 974 or step on its top surface and a protrusion 996 extending radially inward from the outer edge ring 995 adjacent to the annular recess 974. The edge ring 997 has a generally rectangular cross-section and includes an annular recess 998 or step on a radially outer upper surface to accommodate the protrusion 996. The edge ring 997 includes a protrusion 999 extending upward from a radially inner upper surface of the edge ring 997 adjacent to a radially outer surface of the heater plate 132. In some examples, the edge ring 950” is made of silicon (or quartz or silicon carbide), the edge ring 980 is made of silicon or silicon carbide, the edge ring 997 is made of ceramic, aluminum or quartz, and the edge ring 970 is made of quartz, although other materials can be used. The protrusion 996 of the edge ring 970 and the annular recess 998 of the edge ring 997 define a serpentine path to reduce plasma arcing.

[0178] Referring now to FIG. 10A and FIG. 10B instead of relying on capacitance of the conductive edge ring, the edge ring can be made of a dielectric material and can include an embedded conductor without external connections. For example, in FIG. 10A and FIG. 10B , FIG. 9A and FIG. 9B the edge ring 920 can be made of a dielectric material and can include an embedded conductor 1008 made of metal. The top edge ring 910 is made of a conductive material.

[0179] The embedded conductor 1008 includes a vertical conductive portion 1010 and a horizontal conductive portion 1020. The embedded conductor 1008 is arranged to provide a relatively constant capacitance as the top edge ring 910 is raised due to wear, as shown in FIG. 10B In examples of FIG. 10A and FIG. 10B the horizontal conductive portion 1020 provides coupling to the heater plate 132. As the top edge ring 910 moves upward due to wear, the horizontal conductive portion 1020 remains coupled to the heater plate 132. Thus, the capacitance of the delivery component remains approximately the same.

[0180] Referring now to FIG. 11A and FIG. 11B the edge ring 840 is made of a dielectric material (rather than a conductive material as in FIG. 8A and FIG. 8Band includes embedded conductors 1108 without external connections. The top edge ring 810 is made of a conductive material or a dielectric material. The embedded conductors 1108 include an upper horizontal conductor 1110 arranged proximate to and parallel to the lower surface of the top edge ring 810. The upper horizontal conductor 1110 is connected to a vertical conductor 1112 that extends near the middle of the middle edge ring 840. The vertical conductor 1112 is connected to a horizontal conductor 1120 that extends radially inward and is connected to a vertical conductor 1122. The vertical conductor 1122 is arranged near and extends along the radial inner surface of the edge ring 840 near the lower portion.

[0181] In FIG. 11B , as the edge ring 840 is raised to compensate for wear of the top edge ring 810, the coupling between the vertical conductor 1112 and the top edge ring 810 remains relatively constant (and less than or equal to D A ). Likewise, the coupling between the vertical conductor 1122 and the conductive opposing surface of the substrate 130 remains relatively constant (and less than or equal to D A ). In other locations, the embedded conductors have a gap distance greater than or equal to D B .

[0182] Reference is now made to FIG. 11C to FIG. 11E , which shows the arcuate portion of the edge ring 840. The edge ring 840 can be made of a plurality of ceramic green sheets that are stacked and sintered. Prior to sintering, the vertical conductors or vias are created by cutting holes in adjacent ceramic green sheets and filling the holes with a conductive material, such as conductive paste. In some examples, tungsten paste is used. The horizontal conductors are formed by printing traces or conductive planes on the ceramic green sheets using a conductive material. In some examples, the horizontal conductors are printed to overlap and contact the vertical conductors to provide connections therebetween.

[0183] In FIG. 11C , the vertical conductor 1112 or via is shown connected to the conductive plane 1150 that defines the horizontal conductor 1110. In FIG. 11D , where there is no horizontal conductor, the vertical conductor passes through the ceramic green sheet. In FIG. 11E , instead of using the conductive plane shown in FIG. 11D , a plurality of traces 1160 can be used instead of the conductive plane 1150 to implement the horizontal conductor 1110.

[0184] Reference is now made to FIG. 12A and FIG. 12B, the top edge ring 710 of FIG. 7 can be made of a dielectric material instead of a conductive material. The top edge ring 710 includes no embedded conductors 1208 with connections to its exterior. The embedded conductors 1208 include horizontal conductors 1210 arranged parallel to the top surface of the top edge ring 710. The horizontal conductors 1210 are spaced a predetermined distance from the top surface to allow dielectric material to wear without exposing the horizontal conductors 1210. Vertical conductors 1220 extend vertically near the middle portion of the top edge ring 710. The vertical conductors 1220 are connected to the horizontal conductors 1210 and to horizontal conductors 1224 arranged parallel to the bottom surface of the top edge ring 710. The horizontal conductors 1224 allow capacitive coupling with the lift pins 754. The lift pins 754 are made of a conductive material. As FIG. 11B can be seen in FIG. 7, as the top edge ring 710 is raised, the coupling between the lift pins 754 and the horizontal conductors 1224 remains constant.

[0185] Referring now to FIG. 13A and FIG. 13B , the edge ring 840 is made of a dielectric material or a conductive material (as defined herein) and includes one or more doped regions that are more conductive than the remainder of the region that is not doped. The top edge ring 810 is made of a conductive material or a dielectric material.

[0186] In this example, the top surface 1320 of the edge ring 840, located below the top edge ring 810, is doped to a predetermined depth to make the material more conductive than the undoped material. Likewise, the radially inner surface 1322 of the edge ring 840 is also doped to a predetermined depth to make the dielectric material more conductive from the top surface 1320 to the bottom edge of the lower surface 849. The top surface 1320 is electrically connected to the radially inner surface 1322. Although a single continuous doped region is shown, two or more doped regions can be used.

[0187] For example, the edge ring 840 can be made of silicon carbide doped with boron, aluminum, or nitrogen to make selected portions more conductive than the undoped regions. In FIG. 13B , as the middle edge ring is raised due to wear of the top edge ring 810, the conductive portions of the edge ring 840 provide uniform coupling to the adjacent surfaces.

[0188] Referring now to FIG. 14AThe top edge ring 1410 is disposed above the edge rings 1412, 1416, and 1420. The top edge ring 1410 has an inverted "U" shape and includes a ring body 1434, a radially inner leg 1432, and a radially outer leg 1436. The ring body 1434 has a thickness t to allow sufficient material for stability of the edge ring during processing and sufficient material for a number of cycles before replacement due to corrosion. In some examples, the thickness t is in a range of 0.5 mm to 10 mm, although other thicknesses can be used. In some examples, the thickness t is in a range of 0.5 mm to 5 mm, although other thicknesses can be used.

[0189] A top surface 1438 of the radially outer leg 1436 linearly slopes downward (to create a sloped surface) near a middle portion of the top edge ring 1410 at 1438' to a radially outer edge of the top edge ring 1410. The slope 1438' linearly slopes downward from the top surface 1438 by a vertical distance d. A horizontal distance h is provided from the radially outer edge of the "U" shape to where the top surface 1438 begins to slope downward. In some examples, the horizontal distance h is in a range of 0 mm to 10 mm depending on the thickness t, although other horizontal distances can be used. In some examples, d is greater than or equal to t. In some examples, d is in a range of t to 3t. In some examples, d is less than or equal to t. In some examples, d is in a range of 0.25*t to t. The edge rings 1412 and 1416 have an "L" shaped cross section.

[0190] In some examples, the top surface 1438 has an overall thickness H. In some examples, the overall thickness H of the edge ring is in a range of 5 mm to 20 mm. In some examples, the distance d is greater than or equal to 5%, 10%, 20%, 30%, 40%, or 50% of the height H. In some examples, the slope 1438' linearly slopes at an acute angle. In some examples, the slope 1438' slopes at an acute angle in a range of 20° to 70°.

[0191] The edge ring 1410 is generally taller than previous edge rings to allow for more wear and to conform to the "U" shape. As the edge ring wears, it can crack if there is not enough material between the "U" shape and the top surfaces 1438 and 1438'. As can be appreciated, removing material in the radially outer slope reduces the weight of the edge ring 1410, which reduces the load on the actuator. This allows the actuator to provide finer adjustments. The linear slope of the slope 1438' allows for an increased amount of material to be removed without removing too much material between the "U" shape groove and the top surfaces 1438 and 1438' compared to a stepped design. In some examples, the distance d is greater than the thickness t of the ring body 1434 to increase the amount of material removed. In some examples, the horizontal distance h is less than the thickness t of the ring body 1434 to increase the amount of material removed.

[0192] Edge ring 1412 is positioned radially outward of edge ring 1416 and below top edge ring 1410. Edge ring 1412 includes upwardly projecting leg 1448 and leg 1446 extending radially inward from upwardly projecting leg 1448. Edge ring 1416 is positioned adjacent to heating plate 132, radially inward of edge ring 1412, and below substrate 128. Edge ring 1416 includes upwardly projecting leg 1440 and leg 1442 extending radially outward from upwardly projecting leg 1440.

[0193] Edge ring 1420 includes radially outer portion 1452 and radially inner portion 1454 extending radially inward from a lower portion of radially outer portion 1452. Step surface 1455 supports radially outer leg 1436 of top edge ring 1410 when lowered. Upwardly projecting portion 1456 extends upwardly from an inner upper surface of radially inner portion 1454. Lift pins 1460 move correspondingly in vertical holes in radially inner portion 1454 of edge ring 1420 to raise and lower edge ring 1410.

[0194] Referring now to FIG. 14B , top edge ring 1410 includes an alternative upper surface profile. The sloped portion 1464’ of the top surface of edge ring 1410 slopes downward in a radially outward direction. Sloped portion 1464’ transitions into surface 1466 that is generally parallel to the plane that includes substrate 128. Removal of material of the edge ring in sloped portion 1464’ results in a weight reduction of top edge ring 1410. The weight reduction can be made to allow use with a lift actuator that has a lower lifting capacity.

[0195] Referring now to FIG. 14C , radially inner edge 1470 of top edge ring 1410 defines a gap relative to the radially outer surface of upwardly projecting leg 1440 of edge ring 1416. The gap is increased relative to the edge ring system in FIG. 14A and FIG. 14B .

[0196] Referring now to FIG. 15The edge ring system includes a top edge ring 1510, an outer edge ring 1520, and an edge ring 1530. The edge ring 1530 is located below the top edge ring 1510 and radially inward of the outer edge ring 1520. The top edge ring 1510 includes a generally rectangular body 1514 and a radially inward projecting foot 1516 extending from a radially inner upper surface of the top edge ring 1510. The edge ring 1530 is generally rectangular and includes an annular recess 1534 on a radially inner surface thereof. The substrate 128 is received in the annular recess 1534. The outer edge ring 1520 includes a radially outer portion 1522 and an inner portion 1524 extending radially inward from a middle portion of the radially outer portion 1522. Lift pins 1560 are correspondingly moved in vertical holes in the inner portion 1524 of the outer edge ring 1520. A projection 1526 extends upward from a radially inner upper surface of the outer edge ring 1520. The generally rectangular body 1514 of the top edge ring 1510 is received on an upper surface 1555 of the outer edge ring 1520 between the projection 1526 and the radially outer portion 1522.

[0197] In some examples, the top surface 1518 of the edge ring 1510 has a height H before the bevel 1518’. The bevel 1518’ bevels downward from the top surface 1518 by a distance d to a radially outer edge of the top edge ring 1510. In some examples, the distance d is greater than or equal to 5%, 10%, 20%, 30%, 40%, or 50% of the height H. In some examples, the bevel 1518’ bevels downward at an acute angle. In some examples, the bevel 1518’ bevels downward at an acute angle in a range of 20° to 70°. As can be appreciated, removing material to create the bevel 1518’ helps reduce the weight of the edge ring 1510, which reduces the load on the actuators and improves reliability.

[0198] In some examples, the heater plate 132 has a cylindrical central portion 1577 and a projection 1579 extending radially outward from a bottom of the cylindrical central portion. In some examples, the heater plate 132 does not include an RF electrode. In other examples, the RF electrode in the heater plate 132 near the edge ring is removed. For example, the RF electrode is removed in a region 1580 of the heater plate located below the edge ring 1530.

[0199] Reference is now made to FIG. 16A to FIG. 16C which shows a moveable edge ring system 1600. In FIG. 16AThe movable edge ring system 1600 includes a top edge ring 1610 having a ring body 1612. Radially outer feet of the top edge ring 1610 project downwardly from a radially outer surface of the ring body 1612. Radially inner feet 1616 project downwardly from a radially inner surface of the ring body 1612. Inwardly projecting feet 1618 extend radially inwardly from lower ends of the radially inner feet 1616. The inwardly projecting feet 1618 extend below a radially outer edge of the substrate 128. In some examples, the heating layer 132 includes an annular recess 1619, and the inwardly projecting feet 1618 are received in the annular recess 1619 on an upper surface thereof and between the substrate 128 and the annular recess 1619.

[0200] The edge ring 1620 includes a ring body 1622. Radially outwardly projecting feet 1624 extend from an upper radially outer surface of the ring body 1622. Radially inwardly projecting feet 1628 extend radially inwardly from a radially inner lower surface of the ring body 1622. The edge ring 1620 is located radially outwardly of the top edge ring 1610.

[0201] The edge ring 1630 is located radially inwardly of the edge ring 1620 and below the top edge ring 1610. The edge ring 1630 includes a ring body 1632. Radially inwardly projecting feet 1634 extend radially inwardly from an upper radially inner surface of the ring body 1632. As will be further described below in connection with FIG. 17-2 2, the edge ring 1632 can include spacers 1633, such as shims, pins, or projections, to maintain spacing between the edge ring 1630 and the edge rings 1620 and / or 1640. As will also be further described below, an insulating coating can be used.

[0202] The edge ring 1640 is located below the edge ring 1620 and radially outwardly of a lower portion of the edge ring 1630. The edge ring 1640 includes a ring body 1642 from which radially downwardly projecting feet 1644 extend from a radially outer lower surface of the ring body 1642. Inwardly projecting feet 1646 extend radially inwardly from an intermediate interior of the ring body 1642. The inwardly projecting feet 1646 include vertical holes 1647 that receive lift pins 1648. The edge ring 1640 includes an annular recess 1650 and a projection 1652 that define a vertical hole in a lower surface of the edge ring 1640 to receive a guide sleeve 1660 that is disposed in a vertical hole 1664 of the base plate 130. The edge ring 1640 includes an annular recess 1654 on a lower radially inner surface thereof to provide clearance for a radially outer edge of the base plate 130.

[0203] When offset against the lower surface of edge ring 1610 by lift pins 1648, edge ring 1630 defines a first vertical gap 1670 between the radial inner foot 1634 and the upper surface of the heating layer 132. Edge ring 1630 also defines a second vertical gap 1672 between the lower surface of edge ring 1630 and the upper surface of the radially inwardly projecting foot 1646.

[0204] In FIG. 16B , when lift pins 1648 are fully lowered, edge ring 1630 defines a third vertical gap 1680 between the lower surface of edge ring 1610 and the upper surface of edge ring 1630. The lower surface of edge ring 1630 rests on the upper surface of radially inwardly projecting foot 1646. During operation, edge ring 1630 can be disposed in abutting relation to edge ring 1610 by raising lift pins 1648, or in spaced apart relation to edge ring 1610 by lowering lift pins 1648 and edge ring 1630.

[0205] When edge ring 1610 is worn from exposure to plasma, substrate 128 is removed and lift pins 1648 are raised upwardly to edge ring 1630 and edge ring 1610, as shown in FIG. 16C . Edge ring 1610 is removed from the processing chamber through the substrate port using a robot arm (e.g., a vacuum transfer module robot arm). Another of edge ring 1610 is transferred (through the substrate port using the robot arm) onto edge ring 1630, and lift pins 1648 are lowered. In some examples, top ring 1610 is made of a conductive or dielectric material, ring 1630 is made of a conductive material or a dielectric material with embedded electrodes, and rings 1620 and 1640 are made of a dielectric material.

[0206] Referring to FIG. 16D , FIG. 16A-16C Edge ring 1640 can be split into two concentric rings. Inner ring 1680 includes an annular body 1682 and an annular recess 1684 on a lower radial inner surface (similar to annular recess 1650 in FIG. 16A-16C . Inner ring 1680 is made of a conductive material to enhance capacitive coupling with edge ring 1630. This arrangement allows more RF to be transmitted between substrate 130 and edge ring 1630.

[0207] Outer ring 1690 includes an annular body 1692 made of a dielectric material. Annular body 1692 is located radially outward of inner ring 1680. A radial inner surface 1694 of outer ring 1690 is adjacent to a radial outer surface 1686 of inner ring 1680.

[0208] Referring now to FIG. 17 and FIG. 18, many of the foregoing examples include an upper ring exposed to the plasma and a lower ring located below and shielded from direct plasma by the upper ring. For example, a cross-section of a portion of an edge ring system 1700 designed with capacitive coupling is shown in FIG. 17 . The lower portion of the upper ring 1710 is located radially outward of the lower portion of the lower ring 1720.

[0209] To maintain control of the plasma sheath at low bias frequencies, as the upper ring 1710 is exposed to the plasma, experiences erosion, and its height is raised, the value of the coupling capacitance C should remain fixed and relatively constant. In addition, there can be a significant temperature difference between the upper ring 1710 and the lower ring 1720. For example, the temperature difference between the upper ring 1710 and the lower ring 1720 during plasma processing can range from 0 °C to 200 °C (e.g., 100 °C). In some examples, because the lower ring 1720 expands when heated and contracts when cooled, the lower ring 1720 (or the upper ring 1710) can move or walk in a direction parallel to the substrate toward the side of the upper ring 1710, effectively reducing the gap in some radial directions and increasing the gap in other radial directions.

[0210] Assuming C is the capacitance between the upper ring 1710 and the lower ring 1720, as the lower ring 1720 moves away from center (closer to the upper ring 1710 in some radial directions and further away in other radial directions), the capacitance increases because the capacitance is a non-linear function of the gap. More particularly, the capacitance C shifted = S(s') * C centered where s' = d / (R2 - R1), where 0 < s' < 1, and where R is the inner diameter of the upper ring 1710 and R1 is the outer diameter of the lower ring 1720. In FIG. 18 , the relative increase in capacitance is shown as a function of the percent deviation from the nominal gap (%). As can be appreciated, the capacitance is affected when the percent deviation is greater than about 35-40% of the nominal gap.

[0211] Systems and methods according to the present disclosure use spacers (e.g., shims, pins, or protrusions) on the upper or lower rings to limit movement of the upper ring 1710 relative to the lower ring 1720 during heating and cooling experienced during plasma processing. In some examples, the movement is limited to less than or equal to 20%, 30%, or 40% of the nominal gap to limit the effect of the relative movement on the capacitance of the edge ring system.

[0212] Reference is now made to FIG. 19-2 2, which shows various ways to limit movement of the upper ring relative to the lower ring of an edge ring system. In FIG. 19In some embodiments, the edge ring system 1900 includes an upper ring 1910 that includes inner and outer portions 1910-1 and 1910-2, respectively, that are located proximate to the radially inner outer surface of the lower ring 1920. In some embodiments, the upper ring 1910 includes a radially inner portion 1910-1 that is located proximate to the radially inner surface of the lower ring 1920. In some embodiments, the upper ring 1910 includes a radially outer portion 1910-2 that is located proximate to the radially outer surface of the lower ring 1920. FIG. 20-2 2. In some embodiments, various ways to limit movement of the upper ring 1910 relative to the lower ring 1920 are shown.

[0213] In some embodiments, the lower ring 1920 includes a slot 1938 on a radially outer surface thereof. The slot 1938 extends radially inward into the radially outer surface of the lower ring 1920. A shim 1934 is disposed in the slot 1938. In some embodiments, adhesive 1930 is used to retain the shim 1934 in the slot 1938. In some embodiments, the shim 1934 has a rectangular planar, radial side cross-section, although other shapes can be used. In some embodiments, the thickness of the shim 1934 in the radial direction is greater than or equal to the depth of the slot 1938. In some embodiments, the shim 1934 extends radially outward from the lower ring 1920 a distance sufficient to limit movement (given the number of shims used). FIG. 20 In some embodiments, the lower ring 1920 includes a slot 1948 on a radially outer surface thereof. The slot 1948 extends radially inward. A pin 1950 is disposed in the slot 1948. In some embodiments, adhesive 1930 is used to retain the pin 1950 in the slot 1948. In some embodiments, the pin 1950 has a cylindrical shape, although other shapes can be used. In some embodiments, the height of the pin 1950 in the radial direction is greater than or equal to the depth of the slot 1948. In some embodiments, the pin 1950 extends radially from the lower ring 1920 a distance sufficient to limit movement (given the number of pins used).

[0214] FIG. 21 In some embodiments, the lower ring 1920 includes a protrusion 1960 formed on a radially outer surface thereof. In some embodiments, the protrusion 1960 extends partially or entirely along the vertical thickness of the radially outer surface in the vertical direction. In some embodiments, the protrusion 1960 includes a flat surface 1964 extending from the radially outer surface 1962 of the lower edge ring 1920, which is easier to machine and measure dimensions than an arcuate profile. In other words, in some embodiments, the edge ring is initially formed slightly wider without the protrusion 1960, then the radially outer surface is machined or removed in the area between adjacent protrusions to form the protrusion 1960. In other embodiments, the protrusion 1960 includes an arcuate or convex profile in plan view to reduce the surface area in contact with the radially inner opposing surface of the top edge ring and reduce friction when performing height adjustment or replacing the top edge ring without breaking vacuum.

[0215] In some embodiments, the lower ring 1920 includes a protrusion 1960 formed on a radially outer surface thereof. In some embodiments, the protrusion 1960 extends partially or entirely along the vertical thickness of the radially outer surface in the vertical direction. In some embodiments, the protrusion 1960 includes a flat surface 1964 extending from the radially outer surface 1962 of the lower edge ring 1920, which is easier to machine and measure dimensions than an arcuate profile. In other words, in some embodiments, the edge ring is initially formed slightly wider without the protrusion 1960, then the radially outer surface is machined or removed in the area between adjacent protrusions to form the protrusion 1960. In other embodiments, the protrusion 1960 includes an arcuate or convex profile in plan view to reduce the surface area in contact with the radially inner opposing surface of the top edge ring and reduce friction when performing height adjustment or replacing the top edge ring without breaking vacuum. FIG. 22A FIG. 22B In some embodiments, the lower ring 1920 includes a protrusion 1960 formed on a radially outer surface thereof. In some embodiments, the protrusion 1960 extends partially or entirely along the vertical thickness of the radially outer surface in the vertical direction. In some embodiments, the protrusion 1960 includes a flat surface 1964 extending from the radially outer surface 1962 of the lower edge ring 1920, which is easier to machine and measure dimensions than an arcuate profile. In other words, in some embodiments, the edge ring is initially formed slightly wider without the protrusion 1960, then the radially outer surface is machined or removed in the area between adjacent protrusions to form the protrusion 1960. In other embodiments, the protrusion 1960 includes an arcuate or convex profile in plan view to reduce the surface area in contact with the radially inner opposing surface of the top edge ring and reduce friction when performing height adjustment or replacing the top edge ring without breaking vacuum. FIG. 22B In some embodiments, the lower ring 1920 includes a protrusion 1960 formed on a radially outer surface thereof. In some embodiments, the protrusion 1960 extends partially or entirely along the vertical thickness of the radially outer surface in the vertical direction. In some embodiments, the protrusion 1960 includes a flat surface 1964 extending from the radially outer surface 1962 of the lower edge ring 1920, which is easier to machine and measure dimensions than an arcuate profile. In other words, in some embodiments, the edge ring is initially formed slightly wider without the protrusion 1960, then the radially outer surface is machined or removed in the area between adjacent protrusions to form the protrusion 1960. In other embodiments, the protrusion 1960 includes an arcuate or convex profile in plan view to reduce the surface area in contact with the radially inner opposing surface of the top edge ring and reduce friction when performing height adjustment or replacing the top edge ring without breaking vacuum.​​

[0216] In some examples, the protrusions 1960 are coated with a coating material 1964. In some examples, the coating material 1964 is relatively conformal and made of an insulating material. In some examples, the coating is selected from the group consisting of polytetrafluoroethylene (PTFE), perfluoroalkoxy polymer (PFA), or aluminum oxide, yttrium oxide, or yttrium fluoride deposited using atomic layer deposition. The coating material 1964 has an insulating function that prevents shorting and reduces corrosion. The coating material 1964 also ensures a minimum gap between the lower ring 1920 and the upper ring 1910 to prevent shorting. In some examples, the protrusions 1960 extend radially outwardly from the radially outer surface of the lower ring 1920 a distance sufficient to limit movement (given the number of protrusions used).

[0217] In some examples, the lower ring 1920 includes 3 to 8 spacers (shims, pins, or protrusions) arranged at a uniform spacing (e.g., 3 at 120° spacing, 5 at 72° spacing, 8 at 45° spacing (or 360° / N)) around the outer periphery of the lower ring 1920. As can be appreciated, the spacers are generally not configured to completely limit the relative movement of the upper and lower rings. The gaps help reduce binding during height adjustment and / or replacement. Thus, some relative movement is still desired, and 3 shims can still allow for unwanted movement (which can change the effective coupling capacitance). In some examples, the lower ring 1920 includes 5 spacers arranged around the outer periphery of the lower ring 1920 to further limit movement. Depending on the particular configuration, additional spacers (e.g., 6, 7, or 8) provide diminishing benefits in controlling the effective capacitance and increase cost.

[0218] Although the spacers (e.g., shims, pins, or protrusions) are shown arranged on the outer surface of the lower ring 1920, the spacers can be arranged on the inner surface of the lower ring 1920 and / or one or both inner surfaces of the upper ring 1910. Additionally, for any of the foregoing examples (e.g., in FIGS. 1-22), the spacers and / or insulating coating can be arranged on one or both radially opposite surfaces of the edge rings intended for capacitive coupling.

[0219] In some examples, the spacers extend 50 pm to 250 pm in the radially outward direction from the radially outer surface of the edge ring. In some examples, the spacers extend 50 pm to 250 pm in the radially outward direction from the radially outer surface of the edge ring.

[0220] The foregoing description is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure can be implemented in a variety of forms. Therefore, while this disclosure includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent upon a study of the drawings, specification, and appended claims. It should be understood that one or more steps within a method can be executed in various orders (or concurrently) without altering the principles of the disclosure. Further, although each of the embodiments describes at least one feature, any single implementation can include one or more of the features described. Still further, each of the features can be implemented in any combination, even if the combination is not expressly identified in the claims. In other words, one or more of the described features can be omitted from an embodiment without altering the overall scope of the disclosure. In addition, one or more of the described features can be implemented in any embodiment, even if the embodiment is not expressly identified in the claims.

[0221] Various terminology can be used for the sake of clarity to describe a spatial and / or functional relationship of a described element with another described element. This terminology includes the words "connected", "engaged", "coupled", "adjacent", "next to", "on top of", "above", "below", and "disposed". When used in the above description of the disclosure, relationships using the above terminology can be direct relationships, where no other element occurs between the first and second elements, or indirect relationships, where one or more elements occur between the first and second elements (either spatially or functionally). The phrase "at least one of A, B, and C" should be interpreted as meaning A or B or C using a non-exclusive logical OR (OR), and should not be interpreted as meaning "at least one of A and / or at least one of B and / or at least one of C".

[0222] In some implementations, a controller is part of a system, which can be part of the above-described examples. Such systems can include semiconductor processing equipment, including one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems etc.). These systems can be integrated with electronics for controlling the operation of the systems before, during, and after processing of a semiconductor wafer or substrate. The electronics can be referred to as the “controller,” which can control various components or subcomponents of one or more systems. Depending on the process requirements and / or system types, the controller can be programmed to control any of the processes disclosed herein, including the delivery of processing gases, temperature settings (e.g., of heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, positional and operation settings, wafer transfer into and out of the tool and other transfer tools and / or load locks connected to or interfaced with the specific system.

[0223] Broadly speaking, the controller can be defined as electronics having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operation, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits can include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors, or microcontrollers that execute program instructions (e.g., software). Program instructions can be instructions communicated to the controller in the form of various individual settings (or programs) of the various parameters defined for processing a substrate (or a portion thereof) on or against the semiconductor wafer or system. In some embodiments, the operational parameters of the programs can be part of a recipe defined by process engineers to accomplish one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0224] In some implementations, a controller can be part of, or coupled to, a computer that is integrated with, coupled to, otherwise networked to, or a combination thereof, the system. For example, the controller can be in "the cloud" or all or a part of a fab host computer system, which can allow for remote access of the wafer processing. The computer can enable remote access to the system to monitor current progress of fabrication operations, examine a history of past fabrication operations, examine trends or performance metrics from a plurality of fabrication operations, change parameters of current processing, set processing steps to follow a current processing, or start a new processing. In some examples, a remote computer (e.g., a server) can provide processing recipes to a system over a network, which can include a local network or the Internet. The remote computer can include a user interface that enables entry or programming of parameters and / or settings, which are then transmitted over the network to the system. In some examples, the controller receives instructions in the form of data, which specify parameters for each of the processing steps during one or more operations. It should be understood that the parameters can be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control. Thus, as described above, the controller can be distributed across all or a portion of the tool, across multiple tools, or as part of a fab host computer system, among other examples.

[0225] An example system can include, but is not limited to, a plasma etch chamber or module, a deposition chamber or module, a spin-rinse chamber or module, a metal plating chamber or module, a clean chamber or module, a bevel edge etch chamber or module, a physical vapor

[0226] As described above, depending on the process step or steps to be performed by the tool, the controller might communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout a factory, a main computer, another controller, or tools used in material transport that bring containers of wafers to and from tool locations and / or load ports in a semiconductor manufacturing factory.

Claims

1. A movable ring configured for moving an edge ring in a vertical direction within a plasma processing system, wherein, The moving ring includes: Ring-shaped body; An inner protrusion extending radially inward from the annular body; and Outer protrusions extending radially outward from the annular body The outer protrusion is vertically lower than the inner protrusion. The top horizontal surface of the annular body is configured to be received by the annular cavity of the edge ring, the upper surface of the edge ring being exposed to plasma during plasma treatment, and the movable ring is configured to move the edge ring in a vertical direction relative to the substrate support when the bottom horizontal surface of the annular body is vertically biased by a lifting pin.

2. The moving ring according to claim 1, wherein, The annular body is configured to be biased by a plurality of lifting pins, which are circumferentially spaced relative to the bottom horizontal surface of the annular body.

3. The moving ring according to claim 1, wherein, The lower horizontal plane of the inner protrusion is vertically located above the upper horizontal plane of the outer protrusion.

4. The moving ring according to claim 1, wherein, The upper horizontal surface of the inner protrusion is coplanar with the top horizontal surface of the annular body.

5. The moving ring according to claim 1, wherein, The lower horizontal surface of the protruding part is coplanar with the bottom horizontal surface of the annular body.

6. The moving ring according to claim 1, wherein, The ring-shaped body is made of a conductive material.

7. A ring system, comprising: The moving ring according to claim 1; Edge ring, including: The second annular body includes a middle portion, the middle portion including an upper surface configured to face the plasma and a bottom surface located opposite the upper surface; The radial inner support of the second annular body extends downward in the vertical direction from the middle part; The radially outer support of the second annular body extends downward in the vertical direction from the middle portion; and An annular cavity, formed between the radially inner support and the radially outer support, is used to accommodate the top horizontal surface of the movable ring. When the annular body is biased by the lifting pin, the moving ring is biased against the bottom surface of the middle part.

8. The ring system according to claim 7, wherein, The edge ring is configured to be arranged adjacent to the intermediate ring having an "L"-shaped cross-section, wherein the radially inner support of the edge ring is configured to be arranged radially outward from the vertical portion of the L-shaped cross-section and upward from the horizontal portion extending radially outward from the vertical portion.

9. The ring system according to claim 7, wherein, The opposing inner vertical sidewalls of the radial inner support and the radial outer support are substantially perpendicular in the annular cavity.

10. The ring system according to claim 7, wherein, The opposing inner vertical sidewalls of the radial inner support and the radial outer support are substantially parallel in the annular cavity.

11. The edge ring according to claim 7, wherein, The vertical thickness between the upper surface of the middle part and the bottom surface of the middle part is substantially constant between the inner radial support and the outer radial support.

12. The edge ring according to claim 7, wherein, The second annular body has an inverted "U" shape.

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