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. A second edge ring is made of a 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 vertically relative to a substrate support and the first edge ring when biased upward by lift pins. The second edge ring is disposed below the top edge ring and radially outward of the first edge ring.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 62 / 976,088, filed February 13, 2020, and U.S. Provisional Application No. 62 / 882,890, filed August 5, 2019. The entire disclosures of the above-referenced applications are incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to plasma processing systems, and more particularly to edge ring systems having a movable edge ring. Background Art

[0004] The background description provided here is for the purpose of generally presenting the context of the present disclosure. No admission is made, either explicitly or implicitly, that the work of the presently designated inventors is prior art to the present disclosure to the extent that it is described in this background section and in aspects of the specification that were not determined to be prior art at the time the application was filed.

[0005] Substrate processing systems perform processes on substrates (e.g., semiconductor wafers). Examples of substrate processing include deposition, ashing, etching, cleaning, and / or other processes. A process gas mixture may be supplied to a processing chamber to process the substrate. Plasma may be used to ignite the gas to enhance chemical reactions.

[0006] During processing, a substrate is placed on a substrate support. An edge ring is annular and positioned around and adjacent to the radially outer edge of the substrate. The edge ring can be used to shape or focus the plasma onto the substrate. During operation, the substrate and exposed surfaces of the edge ring are etched by the plasma. Consequently, the edge ring wears, and its effect on the plasma varies over time. Summary of the Invention

[0007] 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 a 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 vertically relative to a substrate support and the first edge ring when biased upward by lift pins. The second edge ring is disposed below the top edge ring and radially outward of the first edge ring.

[0008] 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.

[0009] In other features, when the lift pins raise the second edge ring and the top edge ring, the middle portion of the second edge ring moves parallel to the radially outer edge 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 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.

[0010] In other features, the first edge ring includes a second annular recess on its upper radially outer surface. When the top edge ring is in the lowered position, the radially inner leg of the top edge ring is located in the first annular recess and the second annular recess.

[0011] 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. When the top edge ring is in a lowered position, a radially outer leg of the top edge ring is positioned in the annular recess.

[0012] In other features, the third edge ring includes vertical holes 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.

[0013] 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 an embedded conductor completely 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 vertically relative to a substrate support when biased upward by lift pins.

[0014] 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.

[0015] 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.

[0016] In other features, when the lift pins raise the first edge ring and the top edge ring, the middle portion of the first edge ring moves parallel to the radially outer edge of the second edge ring. The top edge ring has an inverted "U" shape.

[0017] In other features, the embedded conductor includes a horizontal conductor disposed in the upper portion and parallel to the upper surface of the first edge ring. The embedded conductor also includes a vertical conductor disposed in the lower portion and parallel to the radially inner surface of the first edge ring. The embedded conductor also includes a conductor connecting the vertical conductor to 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.

[0018] 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. When the top edge ring is in a lowered position, a radially outer leg of the top edge ring is positioned in the annular recess. The third edge ring includes a vertical hole to accommodate the lift pin.

[0019] In other features, the first edge ring is made from a ceramic green sheet including conductive traces and vias.

[0020] A movable edge ring system for a plasma processing system includes a top edge ring. The 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 positioned below the top edge ring. The top edge ring and the first edge ring are configured to move vertically relative to a substrate support when biased upward by lift pins.

[0021] In other features, the 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.

[0022] 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 the 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.

[0023] In other features, when the lift pins raise the first and top edge rings, the middle portion of the first edge ring moves parallel to the radially outer edge of the second edge ring. Doped regions are arranged along the upper and radially inner surfaces 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.

[0024] In other features, the 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. When the top edge ring is in the lowered position, a radially outer leg of the top edge ring is positioned in the annular recess. The third edge ring includes a vertical hole to accommodate a lift pin.

[0025] 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 portion protrudes radially outward from a radially inner surface of the annular body between the upper portion and the middle portion. A second step portion protrudes radially outward from the radially inner surface of the annular body between the middle portion and the lower portion.

[0026] In other features, the annular body is made of a dielectric material and further includes an embedded conductor arranged completely within the annular body. The embedded conductor includes a horizontal conductor arranged in the upper portion parallel to the upper outer surface of the annular body. The embedded conductor also includes a vertical conductor arranged in the lower portion of the annular body parallel to the radial 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 of the annular body is more conductive than the undoped region. The doped region is arranged on the upper surface and the radial inner surface of the annular body. The annular body is made of a ceramic green sheet including conductive traces and through holes.

[0027] 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 within 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.

[0028] In other features, the toroidal body has an L-shaped cross-section. The toroidal 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.

[0029] In other features, the first conductor is arranged parallel to a first outer surface of the annular body. The third conductor is arranged parallel to a second outer surface of the annular body. The second conductor is connected to the first conductor and the third conductor. The annular body includes an upper portion, a middle portion, and a lower portion. A first step is located on the radially inner surface of the annular body between the upper portion and the middle portion and protrudes radially outward therefrom. A second step is located on the radially inner surface of the annular body between the middle portion and the lower portion and protrudes radially outward therefrom.

[0030] In other features, the first conductor is arranged parallel to the first outer surface of the annular body at an upper portion. The second conductor is arranged parallel to the radially inner surface of the annular body at a lower portion. A third conductor connects the first conductor to the second conductor. The annular body is made of a ceramic green sheet including conductive traces and through-holes.

[0031] 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 configured to capacitively couple, but not directly couple, to at least one external conductive component selected from the group consisting of a base plate of the substrate support and another edge ring.

[0032] 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.

[0033] In other features, the doped region includes a first portion disposed along the radially inner surface of the annular body. The doped region includes a second portion disposed on the upper surface of the annular body. The first portion contacts the second portion. The annular body includes an upper portion, a middle portion, and a lower portion. A first step is located on the radially inner surface of the annular body between the upper portion and the middle portion and projects radially outward therefrom. A second step is located on the radially inner surface of the annular body between the middle portion and the lower portion and projects radially outward therefrom.

[0034] In other features, the dielectric material comprises silicon carbide. The dielectric material is doped with an impurity selected from the group consisting of boron, aluminum, or nitrogen.

[0035] 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 a 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 biased by lift pins.

[0036] In other features, when the second edge ring moves upwardly along the first edge ring from the lowered position to the raised position, the second edge ring maintains a fixed surface area within a predetermined gap of the radially outer surface of the first edge ring. The 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.

[0037] In other features, the second edge ring includes an annular body including an upper portion protruding 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 protruding radially outward; and a protrusion extending radially inward from the middle portion and downward to a lower edge of the lower portion.

[0038] Among other features, the securing surface area is defined by a protrusion. The third edge ring is positioned below the top edge ring and radially inward of the first edge ring. The third edge ring has an "L"-shaped cross-section. The fourth edge ring is positioned radially outward of the top edge ring and the second edge ring. The fourth edge ring includes a protrusion 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 body, inner legs, and outer legs. In the lowered position, the top edge ring is proximate to the second edge ring, the third edge ring, and the fourth edge ring.

[0039] In other features, 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.

[0040] A movable edge ring system for a plasma processing system includes a first edge ring made of a conductive material and configured to surround a substrate support. Lift pins are made of the conductive material. A lift pin actuator is configured to bias the lift pins against the first edge ring in a lowered position and selectively move the lift pins to increase the height of the first edge ring relative to the substrate support while maintaining contact between the lift pins and the first edge ring.

[0041] In other features, the second edge ring is positioned 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.

[0042] In other features, the third edge ring is located radially outward and below the first and second edge rings. 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.

[0043] In other features, the third edge ring includes an annular body; and a radially inward projection including a vertical hole to receive a lift pin.

[0044] A movable edge ring system for a plasma processing system includes a first edge ring formed of a dielectric material, including an embedded conductor disposed entirely within the dielectric material, and configured to surround a substrate support. Lift pins are formed of a conductive material. A lift pin actuator is configured to bias the lift pins against the first edge ring in a lowered position and selectively move the lift pins to increase the height of the first edge ring relative to the substrate support while maintaining contact between the lift pins and the first edge ring.

[0045] In other features, the embedded conductor includes a first horizontal conductor arranged parallel to a top surface of the first edge ring, a second horizontal conductor arranged parallel to a bottom surface of the first edge ring, and a third conductor connecting the first horizontal conductor to the second horizontal conductor.

[0046] In other features, the second edge ring is positioned 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 vertically and a radially outer leg extending horizontally.

[0047] In other features, the third edge ring is positioned radially outward and below the first and second edge rings. 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 an annular body and a radially inward projection including a vertical hole to accommodate a lift pin.

[0048] A movable edge ring system for a plasma processing system includes a top edge ring having an inverted "U"-shaped cross-section and comprising an annular body, radially inner legs, and radially outer legs. A first edge ring is made of a conductive material and is at least partially disposed between the radially inner and radially outer legs 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 and second edge rings and includes N cavities to accommodate N lift pins, where N is an integer greater than 2. When displaced by the N lift pins, the top edge ring moves relative to the first, second, and third edge rings and the substrate support.

[0049] Among 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 the radially inner surface of the radially outer leg and including a beveled lower surface extending radially outward from the radial recesses. When the height of the top edge ring is adjusted, the N lift pins deflect the top edge ring within the N radial recesses.

[0050] 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 located on the radial inner surface of the radially outer leg, where N is an integer greater than 2, and include a beveled lower surface extending radially outward from the N radial recesses.

[0051] A movable edge ring system includes edge rings. 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 positioned between the radially inner and radially outer legs 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. When displaced by the N lift pins, the edge ring moves relative to the first edge ring, the second edge ring, and a substrate support.

[0052] In other features, the first edge ring and the second edge ring 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 receive N lift pins in the N radial recesses when adjusting the height of the edge ring.

[0053] The movable edge ring system includes edge rings. 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 located between the radially inner leg and the radially outer leg of the edge ring. A second edge ring is disposed radially inward from the first edge ring. A third edge ring is disposed below and radially outward from the edge ring. The first edge ring and the second edge ring include vertical holes to accommodate lift pins. When displaced by the lift pins, the edge rings move relative to the first edge ring, the second edge ring, the third edge ring, and the substrate support.

[0054] A movable edge ring system for a plasma processing system includes a top edge ring having an inverted "U"-shaped cross-section and comprising an annular body, radially inner legs, and radially outer legs. A first edge ring is made of a dielectric material and includes an embedded conductor disposed entirely within the dielectric material. The first edge ring is configured to surround a substrate support and be at least partially disposed between the radially inner and radially outer legs 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 and second edge rings and includes vertical holes to accommodate lift pins. The top edge ring is movable relative to the first, second, and third edge rings when displaced by the lift pins.

[0055] Among 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 a ring 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 and connected to the vertical conductor.

[0056] 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 including a substrate. A second portion of the upper surface of the annular body is inclined downwardly at an acute angle from the first portion.

[0057] In other features, the first portion of the upper surface is located radially inward of the second portion of the upper surface. The third portion of the upper surface is parallel to a plane including the substrate and is located radially outward of the second portion of the upper surface.

[0058] The 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.

[0059] In other features, the second edge ring is made of a dielectric material and is disposed between the first edge ring and the substrate support. The third edge ring is disposed below and radially outward of the first and second edge rings and includes vertical holes to accommodate lift pins. When deflected by the lift pins, the edge ring moves relative to the first and second edge rings and the substrate support.

[0060] 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. The radially inner portion of the upper surface of the annular body is arranged parallel to a plane including a substrate.

[0061] In other features, the radially outer portion of the upper surface of the annular body slopes downwardly from the radially inner portion at an acute angle.

[0062] A movable edge ring system for a plasma processing system includes an edge ring. An intermediate edge ring is disposed below radially inwardly 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 vertical holes for receiving lift pins. When biased by the lift pins, the edge ring moves vertically relative to the intermediate and outer edge rings.

[0063] Among other features, the intermediate edge ring has a generally rectangular cross-section and an annular recess on its radially inner and upper surface. The substrate is disposed in the annular recess. The outer edge ring includes a radially outer portion and an inner portion extending radially inward from the radially outer intermediate portion.

[0064] 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 the heater plate of the substrate support and the base plate. The bottom of the annular body is located adjacent to the upper surface of the outer edge ring between the radially outer portion and the protrusion.

[0065] A plasma processing system includes a movable edge ring system. A substrate support includes a base plate. A heating plate is coupled to the base plate. The heating plate includes a body including a plurality of radio frequency (RF) electrodes, a cylindrical portion, and a protrusion extending radially outward from the cylindrical portion below the intermediate edge ring.

[0066] In other features, the plurality of RF electrodes are not located in a portion of the protrusion below the intermediate edge ring.

[0067] 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; radially outer legs projecting downwardly from a radially outer surface of the annular body; radially inner legs projecting downwardly from a radially inner surface of the annular body; and inwardly projecting legs extending radially inwardly from lower ends of the radially inner legs. When a substrate is disposed on the substrate support, the inwardly projecting legs are disposed below the substrate. A first edge ring is configured to surround the substrate support and be disposed below the top edge ring, and includes an annular body and radially inwardly projecting legs. When the first edge ring is deflected against the top edge ring, an upper surface of the first edge ring is disposed between the radially inner and radially outer legs of the top edge ring.

[0068] In other features, the 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 outwardly projecting leg extending from an upper radially outer surface of the annular body; and a radially inwardly projecting leg extending radially inwardly from a radially inner and lower surface of the annular body.

[0069] In other features, the inwardly projecting leg of the first edge ring extends radially inward from an upper radially inner surface of the annular body of the first edge ring. The third edge ring is disposed radially outward from 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 inward from a middle portion of the third edge ring.

[0070] In other features, the inwardly projecting leg of the third edge ring includes a vertical hole to receive a lift pin. When biased against the top edge ring, the first edge ring defines a first vertical gap between a lower surface of the first edge ring's radially inner leg 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.

[0071] In other features, when in the lowered position, the first edge ring abuts the inward leg of the third edge ring, and the protrusion defines a third vertical gap between an upper surface of the first edge ring and a lower surface of the top edge ring.

[0072] A plasma processing system includes a processing chamber. A substrate support is disposed in the processing chamber. The processing chamber includes a substrate port. A robotic arm transfers a substrate onto the substrate support. A movable edge ring system is disposed around the substrate support. Lift pins offset the top edge ring and the first edge ring relative to the substrate support.

[0073] In other features, the first edge ring and the top edge ring are raised relative to the substrate support by lift pins, the robot removes the top edge ring, and the robot delivers another top edge ring to the substrate support through the substrate port.

[0074] An edge ring system for a plasma processing system includes an upper ring comprising a first annular body configured to surround a substrate support during plasma processing. A lower ring comprises a second annular body configured to surround the substrate support during plasma processing. When configured for plasma processing, at least a portion of the second annular body of the lower ring is nested within a portion of the first annular body of the upper ring, defining a predetermined gap relative to the portion. N spacers are arranged at N spaced locations on a surface of at least one of the upper and lower rings to reduce a change in the predetermined gap between the annular bodies of the upper and lower rings when the upper and lower rings are heated and cooled during plasma processing, where N is an integer greater than or equal to 3 and less than or equal to 8.

[0075] In other features, at least one of the N spacers comprises a washer positioned in a slot on a radially opposing surface of at least one of the upper and lower rings. The washer has a rectangular cross-section. The slot is located on the radially outer surface of the inner ring. At least one of the N spacers comprises a pin positioned in a slot on a surface of at least one of the upper and lower rings. The slot is located on the radially outer surface of the inner ring. The N spacers are arranged at intervals of 360° / N.

[0076] In other features, at least one of the N spacers includes a protrusion formed on a surface of at least one of the upper ring and the lower ring. The protrusion is located on a radially outer surface of the inner ring. A coating covers the protrusion. The coating includes an insulating material.

[0077] 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. Lift pins raise the upper ring relative to the lower ring to adjust the height of the top surface of the upper edge ring relative to the substrate on the substrate support.

[0078] 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 within a portion of a second annular body of an upper ring exposed to plasma during plasma processing, defining a predetermined gap relative to the portion. N spacers are arranged at N spaced locations on at least one of a radially inner surface and a radially outer surface of the annular body to reduce variations in the predetermined gap when the upper and lower rings are heated and cooled during plasma processing, where N is an integer greater than or equal to 3 and less than or equal to 7.

[0079] In other features, at least one of the N spacers comprises a washer positioned in a slot on at least one of the radially inner and outer surfaces of the annular body. The washer has a rectangular cross-section. The slot is located on the radially outer surface of the first annular body. At least one of the N spacers comprises a pin positioned in a slot on at least one of the radially inner and outer surfaces of the first annular body. The slot is located on the radially outer surface of the first annular body.

[0080] In other features, the N spacers are arranged at intervals of 360° / N. At least one of the N spacers comprises a protrusion formed on at least one of the radially inner surface and the radially outer surface of the first annular body. The protrusion is located on the radially outer surface of the inner ring. A coating covers the protrusion. The coating comprises 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.

[0081] Further scope 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 disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] The present disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0083] Figure 1A is a functional block diagram of an example of a substrate processing system according to the present disclosure;

[0084] Figure 1B and 1C is a cross-sectional view of an example of a movable edge ring according to the present disclosure;

[0085] Figure 2 is a functional block diagram of another example of a substrate processing system according to the present disclosure;

[0086] Figure 3A is a cross-sectional side view of an example of a movable edge ring according to the present disclosure;

[0087] Figure 3B For simulation Figure 3A Electrical schematic diagram of the movable edge ring;

[0088] Figure 4 is a cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0089] Figure 5A and Figure 5B is a diagram illustrating movement of different surfaces of a movable edge ring relative to adjacent structures;

[0090] 6A to 6D is a cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0091] 7A to 7B is a cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0092] Figures 8A to 8Cis a cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0093] Figures 9A to 9C is a cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0094] Figure 9C1 is a partial bottom view of a portion of a top edge ring according to the present disclosure;

[0095] Figure 9C2 is a cross-sectional view of a portion of a top edge ring according to the present disclosure;

[0096] Figures 9D to 9G is a cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0097] Figure 10A and Figure 10B is a cross-sectional side view of another example of a movable edge ring including an embedded conductor according to the present disclosure;

[0098] Figure 11A and 11B is a cross-sectional side view of another example of a movable edge ring including an embedded conductor according to the present disclosure;

[0099] Figures 11C to 11E is a cross-sectional view of an example of a movable edge ring and embedded conductor according to the present disclosure;

[0100] Figure 12A and Figure 12B is a cross-sectional side view of another example of a movable edge ring including an embedded conductor according to the present disclosure;

[0101] Figure 13A and Figure 13B is a cross-sectional side view of another example of a movable edge ring including a doped conductive portion according to the present disclosure;

[0102] Figure 14A and Figure 14B is a cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0103] Figure 15 is a cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0104] 16A to 16D is a cross-sectional side view of another example of a movable edge ring according to the present disclosure;

[0105] Figure 17 is a cross-sectional view of a portion of an upper and lower edge ring according to the present disclosure;

[0106] Figure 18is a graph illustrating capacitance increase as a function of percentage deviation from nominal gap according to the present disclosure;

[0107] Figure 19 is a side cross-sectional view of an edge ring system including an upper ring and a lower ring according to the present disclosure;

[0108] Figure 20 is a side cross-sectional view of an edge ring system including an upper ring and a lower ring including a plurality of shims according to the present disclosure;

[0109] Figure 21 is a side cross-sectional view of an edge ring system including an upper ring and a lower ring including a plurality of pins according to the present disclosure;

[0110] Figure 22A is a side cross-sectional view of an edge ring system including an upper ring and a lower ring including a plurality of protrusions according to the present disclosure; and

[0111] Figure 22B is an enlarged side cross-sectional view of a lower edge ring including a protrusion with a raised flat portion according to the present disclosure.

[0112] Among the drawings, reference numerals may be repeated to identify similar and / or identical elements. DETAILED DESCRIPTION

[0113] During substrate processing, the substrate is placed on a susceptor such as an electrostatic chuck (ESC), a process gas is supplied, and plasma is ignited in a processing chamber. Exposed surfaces of components in the processing chamber are subject to wear due to the plasma.

[0114] For example, an edge ring is positioned around the radially outer edge of a substrate to shape the plasma. After processing a substrate, the exposed surface of the edge ring becomes worn and located at a different height relative to the substrate. As a result, the edge ring's effect on the plasma changes, which in turn alters the effect of the process on the substrate. To reduce process variations due to edge ring wear without breaking vacuum, some processing chambers raise the height of the edge ring to compensate for wear. In many of these systems, the height of the edge ring is automatically adjusted based on the number of cycles and / or the total plasma treatment exposure time. Other systems measure the height of the edge ring and adjust the height based on the measured height.

[0115] When the edge ring height is adjusted, the capacitive coupling between the plasma, sheath, and / or capacitive transfer structure (including the edge ring) changes. These changes in capacitive coupling can lead to non-uniformities in substrate processing over time. Various edge ring arrangements according to the present disclosure significantly reduce capacitance variations in the transfer structure caused by edge ring height variations.

[0116] More specifically, a plasma sheath is generated 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 of the transfer component to the substrate support is maintained while adjusting the edge ring height to compensate for wear. The area of the edge ring and / or nearby structures that are capacitively coupled are designed to minimize changes in the capacitive coupling as the top edge ring moves. In some examples, the capacitance is minimized in areas that move apart as the edge ring height increases. The capacitance is controlled in other surface areas that do not change (or change less) as the edge ring height increases.

[0117] In some examples, the edge ring is made of a conductive material. As used herein, a conductive material is a material having a resistivity less than or equal to 10 4 For example, doped silicon has a resistivity of 0.05 Ωcm, silicon carbide has a resistivity of 1-300 Ωcm, and metals (such as aluminum and copper) have a resistivity of ≈10 -7 In other examples, the edge ring is made of a non-conductive or dielectric material (resistivity > 10 4 The embedded electrodes are designed to minimize changes in capacitive coupling as the top edge ring moves. In other examples, the edge ring is made of a dielectric material and includes doped regions that are more conductive than undoped regions. The doped regions are designed to minimize changes in capacitive coupling as the edge ring moves to offset wear.

[0118] Reference Figure 1A and Figure 2 , which shows an example of a plasma processing chamber using a movable edge ring. As can be appreciated, other types of plasma processing chambers can be used. Figure 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 a capacitively coupled plasma (CCP). The substrate processing system 110 includes a processing chamber 122, which surrounds the other components of the substrate processing system 110 and contains an 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 placed on the substrate support 126.

[0119] By way of example only, the upper electrode 124 can include a gas distribution device 129, such as a showerhead, which introduces and distributes the process gas. The gas distribution device 129 can include a rod having one end connected to the top surface of the processing chamber. The annular body is generally cylindrical and extends radially outward from the opposite end of the rod at a position spaced from the top surface of the processing chamber. The surface or faceplate of the annular body of the showerhead that faces the substrate includes a plurality of holes through which precursors, reactants, etching gases, inert gases, carrier gases, other process gases, or purge gases flow. Alternatively, the upper electrode 124 can include a conductive plate, and the process gas can be introduced in another manner.

[0120] 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 may correspond to a ceramic multi-zone heating plate. A bonding and / or thermal resistance layer 134 may be disposed between the heating plate 132 and the base plate 130. The base plate 130 may include one or more channels 136 to allow a coolant to flow through the base plate 130.

[0121] The RF generation system 140 generates an RF voltage and outputs it to one of the upper electrode 124 and the lower electrode (e.g., the substrate 130 of the substrate support 126). The other of the upper electrode 124 and the substrate 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 by a matching and distribution network 144 to the upper electrode 124 or the substrate 130. In other examples, the plasma can be generated inductively or remotely.

[0122] The 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 via 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). An auxiliary valve may 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 may be used.

[0123] The 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 communicate with the coolant assembly 166 to control the coolant flow through the channel 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 the coolant through the channel 136 to cool the substrate support 126.

[0124] The valve 170 and the pump 172 can be used to discharge reactants from the processing chamber 122. The system controller 180 can be used to control the components of the substrate processing system 110. During plasma processing, the edge ring 182 can be disposed radially outside of the substrate 128. The edge ring height adjustment system 184 can be used to adjust the height of the 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 robotic end effector, and replaced with another edge ring without breaking the vacuum.

[0125] Now referring Figure 1B and Figure 1C , in some examples, the substrate 128 is located on the upper surface 190 of the substrate support 126 (or ESC). In Figure 1B , 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 properly 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 adjuster to adjust the height of the edge ring 182, as will be further described below.

[0126] In Figure 1C , the edge ring 182 is worn and the thickness is reduced to a height h' (h' < h). The height adjuster is used to raise the edge ring 182 to restore the height relationship h between the top surface of the edge ring 182 and the upper surface 190. When the edge ring 182 is sufficiently worn, the edge ring 182 can be replaced with a new edge ring.

[0127] In Figure 2, an example of a substrate processing system 210 according to the present disclosure is shown. The substrate processing system 210 uses an 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 RF power on and off or vary the amplitude or level of the RF power. A tuning circuit 213 can be directly connected to one or more inductive coils 216. The tuning circuit 213 tunes the output of the RF source 212 to a desired frequency and / or a desired phase, matches the impedance of the coils 216, and distributes power between the coils 216. In some examples, the coil drive circuit 211 is replaced with one of the drive circuits described further below in conjunction with controlling the RF bias.

[0128] In some examples, a plenum 220 can be positioned between the coil 216 and the dielectric window 224 to control the temperature of the dielectric window 224 using a flow of hot and / or cold air. The dielectric window 224 is positioned along a side of the process chamber 228. The process chamber 228 also includes a substrate support (or pedestal) 232. The substrate support 232 can include an electrostatic chuck (ESC), a mechanical chuck, or other types of chucks. A process gas is supplied to the process chamber 228, and a plasma 240 is generated within the process chamber 228. The plasma 240 etches the exposed surface of the substrate 234. A driver circuit 252 (e.g., one of those described below) can be used to provide an RF bias to the electrodes in the substrate support 232 during operation.

[0129] A gas delivery system 256 can be used to supply a process gas mixture to the process chamber 228. The gas delivery system 256 can include process and inert gas sources 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 the plenum 220 via a valve 261. The gas can include a cooling gas (air) for cooling the coil 216 and the dielectric window 224. A heater / cooler 264 can be used to heat / cool the substrate support 232 to a predetermined temperature. An exhaust system 265 includes a valve 266 and a pump 267 to remove reactants from the process chamber 228 by purging or evacuating.

[0130] 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, ignition, maintenance, and extinguishing of the plasma, removal of reactants, supply of cooling gas, and the like. Furthermore, as described in detail below, the controller 254 can control various aspects of the coil drive circuit 211 and the drive circuit 252. During plasma processing, the edge ring 282 can be positioned radially outward from the substrate 234. A height adjustment system 284 can be used to adjust the height of the top surface of the edge ring 282. Furthermore, 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.

[0131] During processing, a plasma is ignited in the processing chamber. In some examples, an RF bias is output to the substrate support. To maintain control of the plasma sheath at low bias frequencies, the capacitance C of the transfer components (e.g., top, middle, and bottom edge rings) to the substrate support must be maintained while adjusting the height of the top edge ring due to wear. D In the following examples, the edge ring is made of a conductive or dielectric material with embedded electrodes. As will be described further below, the area providing capacitive coupling is designed to minimize changes in capacitive coupling as the top edge ring moves.

[0132] Now refer to Figure 3A , an edge ring system for a substrate support includes a top edge ring 310, an intermediate edge ring 314, and a bottom edge ring 316. The top edge ring 310 has an inverted "U" shape and includes an annular body 330 connected to a radially inner leg 332 and a radially outer leg 334. The intermediate edge ring 314 has a "U" shape and includes an annular 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 located between the radially inner leg 342 and the radially outer leg 344 of the intermediate edge ring 314.

[0133] The bottom edge ring 316 includes a radially outer portion 350, a middle portion 352, and a radially inner portion 354. An annular recess 360 is disposed on the upper radially inner surface of the bottom edge ring 316 between the radially outer portion 350 and the middle portion 352. An annular recess 364 is disposed on the 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. Similarly, the base plate 130 may 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 may be used, where N is an integer greater than 2. In some examples, the N lift pins are spaced apart at an angle equal to 360 / N.

[0134] During operation, a plasma 380 is generated. A sheath 390 is formed between the plasma 380 and a transfer member 392 (including the top edge ring 310, the middle edge ring 314, and / or the bottom edge ring 316).

[0135] Reference Figure 3B , which shows the electrical model of the plasma, sheath, and transport component 392. The sheath 390 has a sheath capacitance C s , and the transmission component 392 has a transmission capacitance C D If the capacitance of the transfer component 392 changes in response to component wear or height adjustment of the edge ring, processing will be less uniform and performance variations and / or defects may occur.

[0136] Now refer to Figure 4 , various parameters can be adjusted to change the capacitance of the transmission component. Figure 4 , the top edge ring 420 has an inverted "U" shape and includes a radially inner leg 422 connected to a radially outer leg 426 via an annular body 424. The intermediate edge ring 430 has a "U" shape and includes a radially outer leg 432 connected to a radially inner leg 438 via an annular body 436. The radially inner leg 422 of the top edge ring 420 is disposed between the radially inner leg 438 and the radially outer leg 432 of the intermediate edge ring 430. The electrostatic electrode 410 and the RF electrode 412 of the substrate 130 are shown.

[0137] Bottom edge ring 440 includes a middle portion 444, an upper portion 446 (which projects upwardly from middle portion 444 adjacent to the radially outer edge of bottom edge ring 440), and a lower portion 448 (which projects downwardly from middle portion 444 adjacent to the radially outer edge of bottom edge ring 440). Bottom edge ring 440 includes a radially inner portion 450 having an upwardly projecting portion 452 on its upper radially inner surface. Base plate 130 includes a stepped portion 456 that accommodates radially inner portion 450 of bottom edge ring 440. Cavities 462 and 464 in bottom edge ring 440 and base plate 130, respectively, accommodate lift pins 470.

[0138] In some examples, the top edge ring 420 and the middle edge ring 430 are made of a conductive material, while the bottom edge ring 440 is made of a non-conductive material (eg, a dielectric). In some examples, the lift pins 470 are made of a conductive or non-conductive material (eg, a dielectric).

[0139] Now refer to Figure 5A and Figure 5B , when the gap between the opposing surfaces increases, the coupling capacitance between the two conductive surfaces decreases significantly. When the edge ring is raised, the opposing surfaces in region A generally maintain the same gap D AIn contrast, when the edge ring is raised, the gap D between the opposing surfaces in region B is B The coupling capacitance of the opposing conductive surfaces will be affected by both region A and region B. Region A will have a stable coupling capacitance as the edge ring moves, while region B will have a decreasing coupling capacitance as the edge ring moves.

[0140] According to the present disclosure, the coupling capacitance in region A is maximized because it is relatively constant, while the coupling capacitance in region B is minimized because it varies. In some examples, the gap D in region A is A Set to the minimum value, and the gap D in area B B Let 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, the gap is set to a gap of less than or equal to 0.006" or 6 mils for areas where coupling is desired, and a gap of greater than or equal to 0.012" or 12 mils for areas where coupling is not desired. In some examples, the gap is set to a gap of less than or equal to 0.006" or 6 mils for areas where coupling is desired, and a gap of greater than or equal to 0.018" or 18 mils for areas where coupling is not desired.

[0141] exist Figure 5A and Figure 5B , the opposing surfaces of the edge ring body during movement are shown. In region A, the opposing surfaces of the edge ring slide adjacent to each other without significantly changing the gap D therebetween. A In region B, the opposing surfaces of the edge ring slide apart and increase the gap D between them. B .

[0142] In some examples, the gap D A Based on the minimum gap between the opposing surfaces in zone A (d min ) is set. Minimum gap d min Determined based on tolerances and / or thermal expansion of the transfer components for a given process temperature range. A is set equal to the minimum gap d in region A where the capacitance needs to remain constant. min In other areas where capacitance is to be minimized (due to increased gap between opposing surfaces), the gap D B Set to be greater than or equal to k*d min (where k is a value greater than or equal to 2.) In other examples, k is greater than or equal to 3. Thus, the capacitance from region A dominates the transfer capacitance, while the capacitance from region B has a significantly reduced influence on the transfer capacitance.

[0143] Reference Figure 6A and Figure 6B, 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 recessed portion 618 is located between inner leg 612 and outer leg 616. 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.

[0144] Edge ring 630 includes a radially inwardly projecting upper portion 632 connected to a radially outwardly projecting portion 636 via a middle portion 634. In some examples, edge ring 630 has a "Z"-shaped cross-section. A projecting surface 638 extends radially inwardly and downwardly (toward an opposing surface 639 of edge ring 640) from a middle region of middle portion 634 to a lower edge of edge ring 630.

[0145] Edge ring 640 is positioned radially inward from edge ring 630 and below upper portion 632 of edge ring 630. Edge ring 640 includes a body 642 having a generally rectangular cross-section, an upper portion 644, a lower portion 646, and a protrusion 648 that protrudes downward from the lower radially inner surface of edge ring 640. Outer edge ring 650 includes a body 652, a radially inward protrusion 654 that protrudes radially inward adjacent to the upper surface of body 652, and a downward protrusion 656 that protrudes downward from the radially outer surface of outer edge ring 650. Annular recesses 658 and 659 provide clearance for radially outward protrusion 636 and base plate 130, respectively.

[0146] An annular seal 660 is disposed in an annular groove 661 defined between the base plate 130, the heating layer 132, and the edge ring 640 to protect the joint and / or the thermal resistance layer 134 disposed between the heating layer 132 and the base plate 130. The lift pin 662 passes through a guide sleeve 664 disposed in a vertical hole 666 in the base plate 130.

[0147] Top edge ring 620 is positioned on edge ring 630. Inner leg 622 of top edge ring 620 is positioned between inner leg 612 of edge ring 610 and radially inwardly projecting upper portion 632 of edge ring 630. Edge ring 610 is positioned on the stepped surface of heating layer 132. Edge ring 640 is positioned radially outward of heating layer 132 and edge ring 610. Body 652 of outer edge ring 650 is positioned radially outward of edge ring 630. Inwardly projecting portion 654 of outer edge ring 650 is positioned between outer leg 626 of top edge ring 620 and radially outwardly projecting portion 636 of edge ring 630. A vertical gap 690 is defined between edge ring 630 and edge ring 610. A horizontal gap 691 is defined between upper portions of edge rings 630 and 640. A vertical gap is defined between edge ring 630 and outer edge ring 650.

[0148] exist Figure 6BIn FIG. 6 , when the top edge ring 620 wears, the lift pins 662 move upward to bias the edge ring 630 upward to compensate for the wear of the top edge ring 620 due to exposure to plasma and / or other process gas mixtures. As can be seen, the protrusion 638 is arranged in the gap D of the edge ring 640. A Likewise, the top surface of the edge ring 630 is disposed within a gap D between the bottom surface of the annular body and the edge ring 630. A A minimum gap between the lower portions of edge rings 630 and 640 is maintained to maintain constant capacitive coupling. Other increased gaps start with a larger gap (≥ twice the minimum gap) and then increase to reduce the impact on capacitive coupling. Reduced gaps start with and remain greater than twice the minimum gap to reduce the impact on capacitive coupling.

[0149] Now refer to Figure 6C , which shows an exemplary variation of edge ring 630. Upper portion 632 of edge ring 630' extends downwardly adjacent to the upper surface of outer leg 616 of edge ring 610 and adjacent to the upper surface of upper portion 644 of edge ring 640. Inner surface 637 of edge ring 630 extends parallel to (and within a predetermined fixed distance of) radially outer surface 641 of edge ring 630. In some examples, the base height (e.g., the top surface of the top edge ring to the top surface of 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 upper portions 632 of edge ring 630' is in the range of 0.1 mm to 1 mm. In some examples, the gap between the bottom surfaces of upper portions 632 of edge ring 630' is in the range of 0.1 mm to 0.5 mm. Increasing the gap reduces coupling therebetween, and vice versa.

[0150] In some examples, top edge ring 620 is made of quartz, edge ring 630 ′ is made of silicon or silicon carbide, edge ring 610 is made of quartz, and edge ring 640 is made of silicon or silicon carbide, although other materials may be used.

[0151] Now refer to Figure 6D , which shows other variations of edge ring 630" and top edge ring 620'. The upper portion 632 of edge ring 630' extends less radially inwardly than the edge rings 630 and 630' shown above. The inner leg 622 of top edge ring 620' is wider in the radial direction (and extends further radially outward).

[0152] In some examples, top edge ring 620 is made of quartz, edge ring 630 ″ is made of silicon or silicon carbide, edge ring 610 is made of quartz, and edge ring 640 is made of silicon or silicon carbide, although other materials may be used.

[0153] Now refer to Figure 7A and7B , top edge ring 710 has a rectangular cross-section. Intermediate edge ring 720 is "L" shaped and includes vertical legs 722 connected to radially outwardly projecting legs 726. Bottom edge ring 740 includes an annular body 744, an upwardly projecting portion 742, a downwardly projecting portion 749, and an inwardly projecting portion 745.

[0154] Vertical holes 746 extend through the inward projections 745 to allow lift pins 754 to pass through and move the top edge ring 710 accordingly. The inward projections 745 include upward projections 747 located adjacent the pins 754 to define an annular recess for receiving the outwardly projecting legs 726. The inward projections 745 also include downward projections 748 located adjacent the radially inner surface of the bottom edge ring 740. The guide sleeve 750 is located in the annular recess defined by the downward projections 748.

[0155] In some examples, the top edge ring 710 and lift pins 754 are made of conductive materials. The middle edge ring 720 and bottom edge ring 740 are non-conductive and made of dielectric materials. Figure 7B As the top edge ring 710 is raised, capacitive coupling is maintained through the lift pins 754 which are conductive and in contact with the top edge ring 710 .

[0156] Now refer to Figure 8A and Figure 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 protrudes 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 protrudes radially inward toward the base plate 130 to form a step 829.

[0157] The edge ring 840 is positioned 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 gap D between the opposing surfaces of the substrate 130. A The edge ring 840 faces the substrate 130 and moves as the edge ring 840 moves (e.g. Figure 8B As shown) and the other surfaces that vary are located at the gap D of the opposite surface of the substrate 130 B Inside.

[0158] The edge ring 850 includes a main body portion 852 having a generally rectangular cross-section. An annular recess or step 854 is located on the upper radially outer portion of the main body portion 852. The inner legs of the top edge ring 810 are located in the annular recesses 846 and 854.

[0159] In some examples, top edge ring 810 is made of a conductive or dielectric material, edge ring 850 and outer edge ring 820 are made of a dielectric material, and edge ring 840 is made of a conductive material. Although lift pins 870 are shown as passing through vertical holes in edge ring 820, base plate 130 can extend further radially outward, and the lift pins can pass through base plate 130 rather than edge ring 820. In some examples, the radially inward facing surfaces of lower portion 844 and intermediate portion 842 are parallel to the radially outward facing surfaces of base plate 130.

[0160] As the top edge ring 810 and edge ring 840 are raised and lowered, the first surface area of the lower portion 844 of the edge ring 840, which is proximate to (and facing) the substrate 130, remains the same. The second surface area of the middle portion 842 of the edge ring 840, which is located further away from the substrate 130, decreases as the edge ring is raised (because the edge ring 850 is located therebetween).

[0161] Now refer to Figure 8C , 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 substrate 130 radially outwardly of the engagement and / or thermal resistance layer 134 below heater plate 132. Edge ring 880 has an "L"-shaped cross-section and is positioned between edge ring 870 and heater plate 132. An annular recess 882 or step is disposed on the upper radially inner surface of edge ring 880.

[0162] Top edge ring 884 has an inverted "U" shape, an annular body 885, a radially inner leg 886, and a radially outer leg 888. Outer edge ring 892 has a generally rectangular cross-section and is disposed radially outward of edge rings 870 and 884. Outer edge ring 892 has a generally rectangular cross-section, a radially inner upper annular recess 894 or step to accommodate radially outer leg 888, and a radially inner lower annular recess 896 or step to accommodate the lower radially outer portion of base plate 130.

[0163] Now refer to Figure 9A and Figure 9B, 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, outer leg 916 is P times thicker in the radial direction than inner leg 914, where P is greater than or equal to 2 and less than or equal to 5. Edge ring 920 is generally "L"-shaped and includes an upward-pointing leg 922 and a radially inward-pointing leg 924. Edge ring 930 is generally "L"-shaped and includes an upward-pointing leg 932 and a radially outward-pointing leg 934, with the radially outer portion of radially outward-pointing leg 934 adjacent to the radially inner portion of radially inward-pointing leg 924 of edge ring 920.

[0164] Bottom edge ring 940 includes a middle portion 942. An upwardly directed portion 944 extends from a radially outer upper surface of bottom edge ring 940. A downwardly directed portion 948 extends from a radially outer lower surface of bottom edge ring 940. A radially inner portion 946 of bottom edge ring extends radially inwardly below outer leg 916 of top edge ring 910 and a portion of edge ring 920. An upwardly directed protrusion 949 extends upwardly a predetermined distance from the radially inner surface of radially inner portion 946.

[0165] In some examples, edge ring 920 and top edge ring 910 are made of a conductive material. In some examples, edge rings 930 and 940 are made of a dielectric material.

[0166] When the top edge ring is fully lowered, outer legs 916 of top edge ring 910 extend a predetermined distance below the lowermost surface of edge ring 920. Thus, when top edge ring 910 is raised, the opposing surfaces of top edge ring 910 and edge ring 920 remain relatively the same. In some examples, the predetermined distance is greater than or equal to the maximum increase in height of top edge ring 910 due to wear.

[0167] Reference Figure 9C , the top edge ring 950 has an inverted "U" shape and includes an annular body 954, a radially inner leg 952, and a radially outer leg 956. In some examples, the radially outer leg 956 is P times thicker in the radial direction than the radially inner leg 952. The top edge ring 950 includes a radial recess 957 located on the downwardly facing surface of the radially outer leg 956. An additional radial recess 957 is provided for each lift pin. In some examples, three lift pins are arranged around the edge ring and spaced 120° apart. The radial recess 957 includes a beveled lower surface 958 that is inclined downwardly and radially outwardly at an acute angle. The radial recess 957 and the beveled lower surface 958 are offset by the lift pins and help to center the top edge ring 950 relative to the baseplate 130 and the substrate 128.

[0168] exist Figure 9C1 and Figure 9C2 In , additional views of the radial recess are shown. Figure 9C1, a bottom view of a portion of the edge ring is shown. Figure 9C2 In the figure, it is shown that Figure 9C1 9C2-9C2. In some examples, surfaces 990 and 992 have a radius. In some examples, angle θ is in the range of 75° to 105° (e.g., 90°).

[0169] 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 located between radially inner leg 962 and radially outer leg 964 of edge ring 960.

[0170] Edge ring 970 includes an annular recess 974 on its radially inner upper surface. A radially inner portion 972 of edge ring 970 is disposed adjacent to substrate 130 and heater plate 132. Lift pins extend 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 its radially inner upper surface to provide clearance and / or support for the 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 downwardly from its lower radial inner surface.

[0171] In some examples, the base plate 130 includes a conformal seal 971 that conforms to the stepped or lower radially outer surface of the base plate 130. In some examples, the conformal seal 971 is made of a material such as ceramic and reduces arcing. The lower surface of the edge ring 970 includes a first annular recess 976 or step for accommodating the lift pins and a second annular recess 978 for accommodating the base plate 130.

[0172] In some examples, the base height is 3.5 mm. In some examples, edge rings 950 and 980 are made of a conductive material such as silicon or silicon carbide, although other materials may be used. In other examples, edge rings 970 and 986 are made of quartz, although other materials may be used.

[0173] Now refer to Figure 9D , showing Figure 9C 980 is located below the top edge ring 950. Edge ring 980 is generally "L" shaped and includes radially inwardly projecting legs 984 and vertical legs 982. Vertical legs 982 are located between radially inner legs 952 and radially outer legs 956 of top edge ring 950. Edge ring 986 is located below substrate 128 and radially outward of heater plate 132. Edge ring 986 is generally rectangular with an annular recess 988 or step located on its lower outer surface to accommodate radially inwardly projecting legs 984.

[0174] In some examples, the base height (e.g., the top surface of the top edge ring 950 to the top surface of the 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 may also be used.

[0175] Reference Figure 9E , showing other exemplary variations of edge ring systems. Figure 9E In the embodiment shown in FIG. 1 , radially outer legs 956 of top edge ring 950 ′ extend radially outward less and are covered by edge ring 990 . Edge ring 990 has an “L” shaped cross section and includes radially inwardly projecting legs 992 and radially downwardly projecting legs 994 connected to the radially outer portions of radially inwardly projecting legs 992 . In some examples, Figure 9D The top edge ring 950 may be too large to fit through the substrate port into the processing chamber. Figure 9E The two parts 950' and 990 allow the edge ring 990 to be removed and replaced through the substrate port (without breaking vacuum when using a vacuum transfer module). Figure 9D Edge ring 950 in FIG. 1 may be too thick and / or too heavy to be moved by a robotic arm. By using a thinner and lighter top edge ring 990 in combination with edge ring 950 ″, edge ring 990 can be removed when it wears out because it is less thick and lighter.

[0176] In some examples, the base height (e.g., the top surface of top edge ring 950 to the 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 may also be used.

[0177] Reference Figure 9F , which shows something like Figure 9C 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 μm and less than 500 μm, 400 μm, or 350 μm. In some examples, the base height (e.g., the top surface of the top edge ring 950 ′ to the top surface of the substrate 130 ) is 5.5 mm. In some examples, the edge rings 950 ′, 980 , and 970 are made of quartz, although other materials may also be used.

[0178] Reference Figure 9G, outer edge ring 995 defines an annular recess 974 or step on its top surface and a protrusion 996 extending radially inward from outer edge ring 995 adjacent to annular recess 974. Edge ring 997 has a generally rectangular cross-section and includes an annular recess 998 or step on its radially outer upper surface to accommodate protrusion 996. Edge ring 997 includes a protrusion 999 extending upward from an upper radial inner surface of edge ring 997 adjacent to the radial outer surface of heater plate 132. In some examples, edge ring 950" is made of silicon (or quartz or silicon carbide), edge ring 980 is made of silicon or silicon carbide, edge ring 997 is made of ceramic, aluminum, or quartz, and edge ring 970 is made of quartz, although other materials may also be used. Protrusion 996 of edge ring 970 and annular recess 998 of edge ring 997 define a serpentine path to reduce plasma arcing.

[0179] Reference Figure 10A and Figure 10B Instead of relying on a conductive edge ring for capacitance, the edge ring can be made of a dielectric material and can include embedded conductors with no external connections. Figure 10A and Figure 10B middle, Figure 9A and Figure 9B The edge ring 920 in the middle 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.

[0180] Embedded conductor 1008 includes a vertical conductive portion 1010 and a horizontal conductive portion 1020. Embedded conductor 1008 is arranged to provide a relatively constant capacitance as top edge ring 910 rises due to wear, as shown in FIG. Figure 10B As shown. Figure 10A and Figure 10B In the example shown, horizontal conductive portion 1020 provides coupling to heater plate 132. As top edge ring 910 moves upward due to wear, horizontal conductive portion 1020 remains coupled to heater plate 132. Thus, the capacitance of the transmission component remains approximately the same.

[0181] Reference Figure 11A and Figure 11B , the edge ring 840 is made of a dielectric material (instead of Figure 8A and Figure 8BThe top edge ring 810 is made of a conductive material (e.g., a dielectric material) and includes an embedded conductor 1108 with no external connections. The top edge ring 810 is made of a conductive material or a dielectric material. The embedded conductor 1108 includes an upper horizontal conductor 1110 arranged near and parallel to the lower surface of the top edge ring 810. The upper horizontal conductor 1110 is connected to a vertical conductor 1112 extending near the middle of the middle edge ring 840. The vertical conductor 1112 is connected to a horizontal conductor 1120, which extends radially inward and is connected to a vertical conductor 1122. The vertical conductor 1122 is arranged near the lower portion near the radially inner surface of the edge ring 840 and extends along the radially inner surface of the edge ring 840.

[0182] exist Figure 11B As edge ring 840 is raised to compensate for the wear of top edge ring 810, the coupling between vertical conductor 1112 and 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 is less than or equal to D A ). At other locations, the embedded conductor has a value greater than or equal to D B gap distance.

[0183] Now refer to Figures 11C to 11E , which shows the arcuate portion of edge ring 840. Edge ring 840 can be made from multiple ceramic green sheets that are stacked and sintered. Before sintering, vertical conductors or vias are created by cutting holes in adjacent ceramic green sheets and filling the holes with a conductive material (e.g., conductive paste). In some examples, tungsten paste is used. 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 so as to overlap and contact the vertical conductors to provide a connection therebetween.

[0184] exist Figure 11C , vertical conductors 1112 or vias are shown connected to the conductive plane 1150 defining the horizontal conductors 1110. Figure 11D In the case where there is no horizontal conductor, the vertical conductor passes through the ceramic green sheet. Figure 11E Instead of using Figure 11D , a plurality of traces 1160 may be used in place of the conductive plane 1150 to implement the horizontal conductor 1110 .

[0185] Now refer to Figure 12A and Figure 12B, the top edge ring 710 of FIG7 may be made of a dielectric material rather than a conductive material. The top edge ring 710 includes an embedded conductor 1208 that has no external connections thereto. The embedded conductor 1208 includes a horizontal conductor 1210 that is arranged parallel to the top surface of the top edge ring 710. The horizontal conductor 1210 is spaced a predetermined distance from the top surface to allow the dielectric material to wear without exposing the horizontal conductor 1210. A vertical conductor 1220 extends vertically near the middle of the top edge ring 710. The vertical conductor 1220 is connected to the horizontal conductor 1210 and a horizontal conductor 1224 that is arranged parallel to the bottom surface of the top edge ring 710. The horizontal conductor 1224 allows for capacitive coupling with the lift pin 754. The lift pin 754 is made of a conductive material. As Figure 11B As 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.

[0186] Now refer to Figure 13A and Figure 13B , 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 remaining undoped regions. Top edge ring 810 is made of a conductive material or a dielectric material.

[0187] In this example, a top surface 1320 of edge ring 840, located below top edge ring 810, is doped to a predetermined depth to make the material more conductive than undoped material. Similarly, a radially inner surface 1322 of edge ring 840 is also doped to a predetermined depth to make the dielectric material more conductive from top surface 1320 to the bottom edge of lower surface 849. Top surface 1320 is electrically connected to radially inner surface 1322. Although a single continuous doped region is shown, two or more doped regions may be used.

[0188] For example, edge ring 840 may be made of silicon carbide doped with boron, aluminum, or nitrogen to make selected portions of it more conductive than undoped areas. Figure 13B , when the middle edge ring is lifted due to wear of the top edge ring 810, the conductive portion of the edge ring 840 provides uniform coupling to the adjacent surfaces.

[0189] Now refer to Figure 14A, top edge ring 1410 is disposed above edge rings 1412, 1416, and 1420. Top edge ring 1410 has an inverted "U" shape and includes an annular body 1434, radially inner legs 1432, and radially outer legs 1436. Annular body 1434 has a thickness t to allow for sufficient material to achieve edge ring stability during handling and sufficient material to allow for a sufficient number of cycles before replacement due to corrosion. In some examples, thickness t is in the range of 0.5 mm to 10 mm, although other thicknesses may be used. In some examples, thickness t is in the range of 0.5 mm to 5 mm, although other thicknesses may be used.

[0190] Top surface 1438 of radially outer leg 1436 slopes linearly downward (to create an inclined surface) near the middle of top edge ring 1410 at 1438' to the radially outer edge of top edge ring 1410. Inclined portion 1438' slopes linearly downward at a vertical distance d from top surface 1438. A horizontal distance h is provided from the radially outer edge of the "U" shape to the point where top surface 1438 begins to slope downward. In some examples, horizontal distance h ranges from 0 mm to 10 mm, depending on thickness t, although other horizontal distances may be used. In some examples, d is greater than or equal to t. In some examples, d ranges from t to 3t. In some examples, d is less than or equal to t. In some examples, d ranges from 0.25*t to t. Edge rings 1412 and 1416 have an "L"-shaped cross-section.

[0191] In some examples, top surface 1438 has a total thickness H. In some examples, the total thickness H of the edge ring is in a range of 5 mm to 20 mm. In some examples, distance d is greater than or equal to 5%, 10%, 20%, 30%, 40%, or 50% of height H. In some examples, inclined portion 1438' is linearly inclined at an acute angle. In some examples, inclined portion 1438' is inclined at an acute angle in a range of 20° to 70°.

[0192] Edge ring 1410 is substantially taller than previous edge rings to allow for longer wear and conform to the "U" shape. Due to wear, the edge ring may crack if there is insufficient material between the "U" shape and top surfaces 1438 and 1438'. As can be appreciated, removing material from the radially outer inclined portion reduces the weight of edge ring 1410, which reduces the load on the actuator. This allows the actuator to provide finer adjustments. Compared to a stepped design, the linear slope of inclined portion 1438' increases the amount of material that can be removed between the "U"-shaped groove and top surfaces 1438 and 1438' without removing too much material. In some examples, distance d is greater than the thickness t of annular body 1434 to increase the amount of material removed. In some examples, horizontal distance h is less than the thickness t of annular body 1434 to increase the amount of material removed.

[0193] Edge ring 1412 is positioned radially outward of edge ring 1416 and below top edge ring 1410. Edge ring 1412 includes upwardly projecting legs 1448 and legs 1446 extending radially inward from upwardly projecting legs 1448. Edge ring 1416 is positioned adjacent to heater plate 132, radially inward of edge ring 1412, and below substrate 128. Edge ring 1416 includes upwardly projecting legs 1440 and legs 1442 extending radially outward from upwardly projecting legs 1440.

[0194] Edge ring 1420 includes a radially outer portion 1452 and a radially inner portion 1454 extending radially inward from a lower portion of radially outer portion 1452. When lowered, step surface 1455 supports radially outer leg 1436 of top edge ring 1410. Upward projection 1456 extends upward from the inner upper surface of radially inner portion 1454. Lift pins 1460 move correspondingly within vertical holes in radially inner portion 1454 of edge ring 1420 to raise and lower edge ring 1410.

[0195] Now refer to Figure 14B , top edge ring 1410 includes an alternative upper surface profile. An inclined portion 1464' of the top surface of edge ring 1410 slopes downward in a radially outward direction. Inclined portion 1464' transitions into a surface 1466 that is generally parallel to a plane including substrate 128. Removing material from the edge ring in inclined portion 1464' reduces the weight of top edge ring 1410. This weight reduction may be achieved to allow for use with lift actuators having lower lift capabilities.

[0196] Reference Figure 14C , the radially inner edge 1470 of the top edge ring 1410 defines a gap relative to the radially outer surface of the upwardly projecting legs 1440 of the edge ring 1416. Figure 14A and Figure 14B In the edge ring system, this gap increases.

[0197] Reference Figure 15The edge ring system includes a top edge ring 1510, an outer edge ring 1520, and an edge ring 1530. Edge ring 1530 is located below top edge ring 1510 and radially inward of outer edge ring 1520. Top edge ring 1510 includes a generally rectangular body 1514 and radially inwardly projecting legs 1516 extending from the radially inner upper surface of top edge ring 1510. Edge ring 1530 is generally rectangular and includes an annular recess 1534 located on its upper radial inner surface. Substrate 128 is received in annular recess 1534. Outer edge ring 1520 includes a radially outer portion 1522 and an inner portion 1524 extending radially inward from a central portion of radially outer portion 1522. Lift pins 1560 move in response to vertical holes in inner portion 1524 of outer edge ring 1520. Protrusions 1526 extend upward from the radially inner upper surface of 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 protrusion 1526 and the radially outer portion 1522 .

[0198] In some examples, the top surface 1518 of the edge ring 1510 has a height H before the inclined portion 1518'. The inclined portion 1518' slopes downwardly from the top surface 1518 to the radially outer edge of the top edge ring 1510 at a distance d. 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 inclined portion 1518' slopes downwardly at an acute angle. In some examples, the inclined portion 1518' slopes at an acute angle ranging from 20° to 70°. As can be appreciated, the material removed to create the inclined portion 1518' helps reduce the weight of the edge ring 1510, which reduces the load on the actuator and improves reliability.

[0199] In some examples, the heater plate 132 has a cylindrical center portion 1577 and a protrusion 1579 extending radially outward from the bottom of the cylindrical center portion. In some examples, the heater plate 132 does not include an RF electrode. In other examples, the RF electrode is removed from the heater plate 132 located near the edge ring. For example, the RF electrode is removed from a region 1580 of the heater plate located below the edge ring 1530.

[0200] Reference 16A to 16C , which shows a movable edge ring system 1600. Figure 16A, movable edge ring system 1600 includes a top edge ring 1610 having an annular body 1612. Radially outer legs of top edge ring 1610 project downwardly from the radially outer surface of annular body 1612. Radially inner legs 1616 project downwardly from the radially inner surface of annular body 1612. Inwardly projecting legs 1618 extend radially inwardly from the lower ends of radially inner legs 1616. Inwardly projecting legs 1618 extend below the radially outer edge of substrate 128. In some examples, heating layer 132 includes an annular recess 1619, and inwardly projecting legs 1618 are received in annular recess 1619 on an upper surface thereof and between substrate 128 and annular recess 1619.

[0201] Edge ring 1620 includes an annular body 1622. Radially outwardly projecting legs 1624 extend from the upper radially outer surface of annular body 1622. Radially inwardly projecting legs 1628 extend radially inwardly from the radially inner lower surface of annular body 1622. Edge ring 1620 is located radially outwardly of top edge ring 1610.

[0202] Edge ring 1630 is located radially inward of edge ring 1620 and below top edge ring 1610. Edge ring 1630 includes an annular body 1632. Radially inwardly projecting legs 1634 extend radially inward from the upper radial inner surface of annular body 1632. Figure 17-2 As further described, edge ring 1632 may include spacers 1633, such as washers, pins, or protrusions, to maintain spacing between edge ring 1630 and edge rings 1620 and / or 1640. As also described further below, an insulating coating may be used.

[0203] Edge ring 1640 is positioned below edge ring 1620 and radially outward of the lower portion of edge ring 1630. Edge ring 1640 includes an annular body 1642 with radially downwardly projecting legs 1644 extending from the radially outer lower surface of annular body 1642. Inwardly projecting legs 1646 extend radially inward from the central interior of annular body 1642. Inwardly projecting legs 1646 include vertical holes 1647 that receive lift pins 1648. Edge ring 1640 includes an annular recess 1650 and a projection 1652 that define vertical holes in the lower surface of edge ring 1640 to receive guide sleeve 1660 disposed in vertical holes 1664 of base plate 130. Edge ring 1640 includes an annular recess 1654 on its lower radial inner surface to provide clearance for the radially outer edge of base plate 130.

[0204] When biased against the lower surface of edge ring 1610 by lift pins 1648, edge ring 1630 defines a first vertical gap 1670 between radially inner leg 1634 and the upper surface of 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 radially inwardly projecting leg 1646.

[0205] exist Figure 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 legs 1646. During operation, edge ring 1630 can be positioned in an abutting relationship with edge ring 1610 by raising lift pins 1648, or in a spaced relationship from edge ring 1610 by lowering lift pins 1648 and edge ring 1630.

[0206] When the edge ring 1610 is worn due to exposure to the plasma, the substrate 128 is removed and the lift pins 1648 raise the edge ring 1630 and the edge ring 1610 upward, as shown in FIG. Figure 16C As shown. Edge ring 1610 is removed from the processing chamber through the substrate port using a robot (e.g., a vacuum transfer module robot). The other edge ring 1610 is transferred (using a robot through the substrate port) 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.

[0207] refer to Figure 16D , Figures 16A-16C The edge ring 1640 can be split into two concentric rings. The inner ring 1680 includes an annular body 1682 and an annular recess 1684 (similar to Figures 16A-16C The inner ring 1680 is made of a conductive material to enhance capacitive coupling with the edge ring 1630. This arrangement allows more RF to be transmitted between the substrate 130 and the edge ring 1630.

[0208] The outer ring 1690 includes an annular body 1692 made of a dielectric material. The annular body 1692 is located radially outward of the inner ring 1680. The radially inner surface 1694 of the outer ring 1690 is adjacent to the radially outer surface 1686 of the inner ring 1680.

[0209] Reference Figure 17 and Figure 18Many of the aforementioned examples include an upper ring exposed to the plasma and a lower ring located below and shielded from the 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. Figure 17 The lower portion of the upper ring 1710 is located radially outward of the lower portion of the lower ring 1720 .

[0210] To maintain control of the plasma sheath at low bias frequencies, the value of the coupling capacitor C should remain fixed and relatively constant as the upper ring 1710 is exposed to the plasma, undergoes erosion, and increases in height. Furthermore, there may be a significant temperature difference between the upper ring 1710 and the lower ring 1720. For example, during plasma processing, the temperature difference between the upper ring 1710 and the lower ring 1720 may be in the range of 0°C to 200°C (e.g., 100°C). In some examples, as the lower ring 1720 expands upon heating and contracts upon cooling, the lower ring 1720 (or upper ring 1710) may move or travel in a direction parallel to the substrate toward one side of the upper ring 1710, effectively reducing the gap in some radial directions and increasing the gap in other radial directions.

[0211] Assuming C is the capacitance between the upper ring 1710 and the lower ring 1720, as the lower ring 1720 moves away from the center (closer to the upper ring 1710 in some radial directions and further away from the upper ring 1710 in other radial directions), the capacitance increases because the capacitance is a nonlinear function of the gap. More specifically, the capacitance C shifted =S(s')*C centered , where s'=d / (R2-R1), where 0≤s'≤1, and where R2 is the inner diameter of the upper ring 1710 and R1 is the outer diameter of the lower ring 1720. Figure 18 , the relative increase in capacitance is shown as a function of the percentage (%) of deviation from the nominal gap. As can be appreciated, the capacitance is affected when the percentage of deviation is greater than about 35-40% of the nominal gap.

[0212] Systems and methods according to the present disclosure use spacers (e.g., shims, pins, or protrusions) on either the upper ring or the lower ring 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, movement is limited to less than or equal to 20%, 30%, or 40% of the nominal gap to limit the effect of relative movement on the capacitance of the edge ring system.

[0213] Now refer to Figure 19-2 2, which shows various ways of limiting the movement of the upper ring relative to the lower ring of the edge ring system. Figure 19In FIG, the edge ring system 1900 includes an upper ring 1910 including inner and outer portions 1910-1 and 1910-2, respectively, located adjacent to radially inner outer surfaces of a lower ring 1920. Figure 20-2 2, various ways of limiting the movement of the upper ring 1910 relative to the lower ring 1920 are shown.

[0214] exist Figure 20 , lower ring 1920 includes a slot 1938 on its radially outer surface. Slot 1938 extends radially inwardly into the radially outer surface of lower ring 1920. A shim 1934 is disposed in slot 1938. In some examples, an adhesive 1930 is used to retain shim 1934 in slot 1938. In some examples, shim 1934 has a rectangular, planar, radial side cross-section, although other shapes may be used. In some examples, the thickness of shim 1934 in the radial direction is greater than or equal to the depth of slot 1938. In some examples, shim 1934 extends radially outwardly from lower ring 1920 to a distance sufficient to limit movement (given the number of shims used).

[0215] exist Figure 21 , lower ring 1920 includes slots 1948 on its radially outer surface. Slots 1948 extend radially inward. Pins 1950 are disposed in slots 1948. In some examples, adhesive 1930 is used to retain pins 1950 in slots 1948. In some examples, pins 1950 have a cylindrical shape, although other shapes may be used. In some examples, the height of pins 1950 in the radial direction is greater than or equal to the depth of slots 1948. In some examples, pins 1950 extend radially from lower ring 1920 to a distance sufficient to limit movement (given the number of pins used).

[0216] exist Figure 22A and Figure 22B In the embodiment, the lower ring 1920 includes a protrusion 1960 formed on its radial outer surface. In some examples, the protrusion 1960 extends partially or entirely along the vertical thickness of the radial outer surface in the vertical direction. Figure 22B In the embodiment shown, protrusion 1960 includes a flat surface 1964 extending from a radially outer surface 1962 of lower edge ring 1920, which is easier to machine and inspect for size than an arcuate profile. In other words, in some examples, the edge ring is initially formed slightly wider without protrusions 1960, and then the radially outer surface is machined or removed in the areas between adjacent protrusions to form protrusions 1960. In other examples, 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 adjustments or replacing the top edge ring without breaking vacuum.

[0217] In some examples, protrusions 1960 are coated with a coating material 1964. In some examples, 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. Coating material 1964 provides an insulating function that prevents short circuits and reduces corrosion. Coating material 1964 also ensures a minimum gap between lower ring 1920 and upper ring 1910 to prevent short circuits. In some examples, protrusions 1960 extend radially outward from the radially outer surface of lower ring 1920 to a distance sufficient to limit movement (given the number of protrusions used).

[0218] In some examples, the lower ring 1920 includes 3 to 8 spacers (shims, pins, or protrusions) arranged around the outer periphery of the lower ring 1920 at uniform spacing (e.g., 3 at 120° spacing, 5 at 72° spacing, and 8 at 45° spacing (or 360° / N)). As can be appreciated, the spacers are generally not configured to completely restrict relative movement of the upper and lower rings. The gaps help reduce engagement during height adjustment and / or replacement. Therefore, some relative movement is still desirable, and 3 shims may still allow for undesirable movement (which may 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 restrict movement. Additional spacers (e.g., 6, 7, or 8) provide diminishing benefits in controlling the effective capacitance and increase cost, depending on the specific configuration.

[0219] Although spacers (e.g., shims, pins, or protrusions) are shown as being disposed on the outer surface of the lower ring 1920, the spacers may be disposed 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 aforementioned examples (e.g., in Figures 1-22), spacers and / or insulating coatings may be disposed on one or both diametrically opposed surfaces of the edge rings intended for capacitive coupling.

[0220] In some examples, the spacer extends in a radially outward direction from the radially outer surface of the edge ring by a range of 50 μm to 250 μm. In some examples, the spacer extends in a radially outward direction from the radially outer surface of the edge ring by a range of 50 μm to 250 μm.

[0221] The foregoing description is merely illustrative in nature and is in no way intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because other modifications will become apparent when studying the drawings, description and appended claims. It should be understood that one or more steps in the method can be performed in a different order (or simultaneously) without changing the principles of the present disclosure. In addition, although each embodiment is described above as having certain features, any one or more of those features described with respect to any embodiment of the present disclosure can be implemented in the features of any other embodiment and / or combined with the features of any other embodiment, even if the combination is not explicitly described. In other words, the embodiments described are not mutually exclusive, and the replacement of one or more embodiments with each other remains within the scope of the present disclosure.

[0222] Various terms are used to describe the spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers, etc.), including "connected," "engaged," "coupled," "adjacent," "next to," "on top of," "above," "below," and "disposed." Unless the relationship between a first and a second element is explicitly described as "direct," when such a relationship is described in the above disclosure, the relationship can be a direct relationship, in which there are no other intervening elements between the first and second elements, but can also be an indirect relationship, in which there are one or more intervening elements (spatially or functionally) between the first and second elements. As used herein, the phrase "at least one of A, B, and C" should be construed to mean a logical (A or B or C), using a non-exclusive logical OR, and should not be construed to mean "at least one of A, at least one of B, and at least one of C."

[0223] In some implementations, the controller is part of a system that can be part of the examples above. Such a system can include semiconductor processing equipment that includes 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 electronic devices for controlling their operation before, during, and after processing of semiconductor wafers or substrates. The electronic device can be referred to as a "controller" that can control various components or subcomponents of one or more systems. Depending on the processing requirements and / or system type, the controller can be programmed to control any of the processes disclosed herein, including the delivery of process gases, temperature settings (e.g., 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, position and operation settings, wafer transfer in and out tools and other transfer tools and / or load locks connected to or interfaced with a specific system.

[0224] In general, a controller can be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits can include chips in the form of firmware that stores 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). The program instructions can be instructions sent to the controller in the form of various separate settings (or program files) that define operating parameters for performing specific processes on or for a semiconductor wafer or system. In some embodiments, the operating parameters can be part of a recipe defined by a process engineer to complete one or more process steps during the manufacture of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or the die of the wafer.

[0225] In some implementations, the controller can be part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller can be in the "cloud" or all or part of a wafer fab host system that can allow remote access to wafer processing. The computer can enable remote access to the system to monitor the current progress of manufacturing operations, review the history of past manufacturing operations, review trends or performance metrics for multiple manufacturing operations, change parameters of a current process, set processing steps to follow the current process, or start a new process. In some examples, a remote computer (e.g., a server) can provide process recipes to the system via a network (which can include a local network or the Internet). The remote computer can include a user interface that enables the input or programming of parameters and / or settings, which are then sent from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify parameters for each processing step to be performed 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 the controller is configured to interface with or control. Thus, as described above, the controller can be distributed, for example, by including one or more discrete controllers networked together and working toward a common purpose (e.g., processing and control as described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on a chamber communicating with one or more integrated circuits remotely (e.g., at a platform level or as part of a remote computer), which combine to control processing on the chamber.

[0226] Example systems may include, but are not limited to, plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used in the manufacture and / or preparation of semiconductor wafers.

[0227] As described above, depending on one or more processing steps to be performed by the tool, the controller can 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 the factory, a host computer, another controller, or tools used in the material transport of wafer containers to and from tool locations and / or load ports in a semiconductor manufacturing facility.

Claims

1. An edge ring for a plasma processing system, the edge ring comprising: a first annular body configured to surround the substrate support during plasma processing; upper surface; lower surface; radial inner surface; radial outer surface; as well as N spacers arranged at N spaced locations on the radially outer surface of the edge ring to reduce a change in a predetermined gap between the first annular body of the edge ring and a second edge ring separated from the edge ring as the edge ring is heated and cooled during plasma processing, wherein N is an integer greater than or equal to 3 and less than or equal to 8, wherein the N spacers extend radially outward from the radially outer surface of the first annular body to a distance sufficient to limit movement of the first annular body of the edge ring relative to a second edge ring during heating and cooling during plasma processing.

2. The edge ring of claim 1, wherein: The N spacers are arranged at a pitch of 360° / N.

3. The edge ring of claim 1 , wherein: At least one of the N spacers includes a protrusion formed on the radially outer surface of the edge ring. The edge ring of claim 3 , further comprising a coating covering the protrusion.

5. The edge ring of claim 4, wherein: The coating comprises an insulating material.

6. The edge ring of claim 5 , wherein 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. The edge ring of claim 1 , wherein N=5.

8. An edge ring system comprising the edge ring according to claim 1, wherein: The edge ring corresponds to a first edge ring, and the edge ring system further includes: The second edge ring includes a second annular body configured to surround the substrate support during plasma processing.

9. The edge ring system of claim 8, wherein: The first edge ring is an upper edge ring, and the second edge ring is a lower edge ring.

10. The edge ring system of claim 9, further comprising lift pins to raise the upper edge ring relative to the lower edge ring to adjust the height of the upper surface of the upper edge ring relative to the substrate on the substrate support.

11. The edge ring system of claim 8, wherein: The first edge ring is a lower edge ring, and the second edge ring is an upper edge ring.

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