WO2020231665A1

WO2020231665A1 - Titanium liner to reduce metal contamination

Info

Publication number: WO2020231665A1
Application number: PCT/US2020/031353
Authority: WO
Inventors: Wei Liu; Johanes F. Swenberg; Theresa Kramer Guarini; Vladimir Nagorny
Original assignee: Applied Materials, Inc.
Priority date: 2019-05-13
Filing date: 2020-05-04
Publication date: 2020-11-19
Also published as: KR20210153155A; TW202105454A

Abstract

Embodiments described herein relate to apparatus and techniques for reducing an occurrence of metal contamination in a processing chamber while process a substrate using a decoupled plasma formed in the processing chamber. A liner substantially prevents contact between the plasma any aluminum or aluminum oxide (e.g., anodized aluminum) in the processing chamber. In one embodiment, the liner is a unitary apparatus positioned in the processing chamber. In one embodiment, the liner is deposited on interior walls of the chamber body via a

Description

TITANIUM LINER TO REDUCE METAL CONTAMINATION

BACKGROUND

Field

[0001] Embodiments of the present disclosure generally relate to semiconductor device processing apparatus, and more specifically, to a liner for a processing chamber, and processing chambers including the same.

Description of the Related Art

[0002] Various processes are used to deposit films on a substrate. Film deposition is generally accomplished by introducing process gasses into a processing chamber that contains the substrate. The process gasses are activated by, for example, radio frequency (RF) power, within the processing chamber. The activated gas forms a plasma in the processing chamber to facilitate etching or deposition of a material.

[0003] Aluminum liners or liners coated with aluminum oxide are typically disposed in the chamber to prevent damage to the chamber walls due to etching or ion bombardment. However, the aluminum or aluminum oxide liners result in metal contamination of the films deposited on the substrate. For example, ions and radicals of the plasma contact the liners which causes particles of the liners (e.g., metal particles) to mix with the plasma and be deposited on the substrate. Thus, the particles of the liners result in metal contamination of the films deposited on the substrate.

[0004] Accordingly, an improved apparatus is needed to reduce metal contamination in the processing chamber.

SUMMARY

[0005] In one embodiment, an apparatus is provided which includes a processing chamber having one or more chamber walls, a bottom, and a lid defining a process volume therein. A cathode assembly is disposed in the process volume. A sidewall shield is disposed in the processing chamber and surrounds the process volume. A cathode shield is disposed in the process volume and surrounds the cathode assembly. The sidewall shield and the cathode shield are fabricated from a titanium containing material.

[0006] In another embodiment, an apparatus is provided which includes a processing chamber having one or more chamber walls, a bottom, and a lid defining a process volume therein. A cathode assembly is disposed in the process volume. A lower liner is disposed in the processing chamber surrounding at least a portion of the cathode assembly. An upper liner is disposed in the processing chamber surrounding at least a portion of the process volume. A portion of the upper liner extends over the lower liner. A sidewall shield is disposed radially inward of the upper liner and the lower liner. The sidewall shield surrounds at least the process volume and at least a portion of the cathode assembly. A cathode shield is disposed in the process volume and surrounds the cathode assembly. The sidewall shield and the cathode shield are fabricated from a titanium containing material.

[0007] In another embodiment, an apparatus is provided which includes a chamber shield fabricated from a titanium containing material. The chamber shield includes a first portion and a second portion substantially normal to the first portion. A filleted edge is between the first portion and the second portion. A first port is formed through the first portion. A second port is formed through the first portion opposite the first port. A slit valve opening is formed through the first portion between the first port and the second port. An exhaust port is formed in the first portion opposite the slit valve opening.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, as the disclosure may admit to other equally effective embodiments. [0009] Figure 1 is a schematic cross-sectional view of a processing chamber according to one embodiment.

[0010] Figure 2 is a schematic representation of a sidewall shield according to one embodiment.

[0011] Figure 3 is a bottom view of the sidewall shield according to one embodiment.

[0012] Figure 4 is a top view of a support disk according to one embodiment.

[0013] Figure 5 is an enlarged schematic cross-sectional view of a portion of the processing chamber according to one embodiment.

[0014] Figure 6 is an enlarged schematic cross-sectional view of another portion of the processing chamber according to one embodiment.

[0015] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

DETAILED DESCRIPTION

[0016] Embodiments described herein relate to apparatus and techniques for reducing an occurrence of metal contamination in a processing chamber while processing a substrate using a plasma formed in the processing chamber. A liner substantially prevents contact between the plasma and any metal (e.g., aluminum or aluminum oxide, such as anodized aluminum) in the processing chamber, such as chamber sidewalls. In one embodiment, the liner is a unitary apparatus positioned in the processing chamber. In one embodiment, the liner is a coating deposited on interior walls of the chamber body via a deposition process.

[0017] Front-side aluminum contamination of the substrate is specified at less than about 5x10⁹ at/cm², according to some device formation processes. Using conventional aluminum chamber liners, front-side aluminum on the substrate may be between about 2x10¹⁰ at/cm² and about 5x10¹⁰ at/cm² with an RF power of 1000 W_eff. If the RF power is increased to about 2000 W_etr with the conventional aluminum liners, the front-side aluminum contamination on the substrate is about 1x10¹¹ at/cm² or greater. A similar increase in the front-side contamination occurs if the pressure in the processing chamber is decreased during processing.

[0018] Aspects discussed herein enable use of increased RF power or reduced pressure without increasing aluminum contamination of the substrate.

[0019] Figure 1 is a schematic cross-sectional view of a processing chamber 100 according to one embodiment. The processing chamber 100 includes sidewalls 102, a bottom 1 12, and a lid 104 coupled to the sidewalls 102. The lid 104, the sidewalls 102, and the bottom 1 12 define a process volume 1 10 therein. A cathode assembly 1 14 is disposed in the process volume 1 10. The cathode assembly 1 14 is coaxial with the lid 104. The cathode assembly 1 14 includes an electrostatic chuck 134 and a ring 132 disposed therearound. In one embodiment, the electrostatic chuck 134 is fabricated from a ceramic material and includes one or more electrodes (not shown) disposed therein. A chucking voltage is applied to the electrodes to electrostatically hold a substrate to the electrostatic chuck 134. During processing, a substrate (not shown) is disposed on the cathode assembly 1 14 and a layer is deposited on the substrate.

[0020] In one embodiment, which may be combined with one or more embodiments described above, the ring 132 is fabricated from a quartz containing material. The ring 132 surrounds and circumscribes at least a portion of the electrostatic chuck 134. An upper liner 106 is disposed adjacent to and extends along an upper portion of the sidewalls 102. A lower liner 108 is disposed adjacent to and extends along a lower portion of the sidewalls 102. In one embodiment, which may be combined with one or more embodiments described above, an inner radius of the upper liner 106 is substantially the same as an inner radius of the lower liner 108. A lower end of the upper liner 106 extends over and radially inward of the lower liner 108 to substantially prevent the plasma from travelling behind (i.e., radially outward) the upper liner 106 and the lower liner 108. In one embodiment, which may be combined with one or more embodiments described above, the lower liner 108 extends along the bottom 1 12 from the sidewall 102 to the cathode assembly 1 14.

[0021] In one embodiment, which may be combined with one or more embodiments described above, the upper liner 106 and the lower liner 108 are fabricated from an aluminum oxide (e.g., anodized aluminum) containing material. A support disk 120 is disposed on the lower liner 108 adjacent to the bottom 1 12 of the processing chamber 100. The support disk 120 is disposed between the cathode assembly 1 14 and the sidewalls 102 and includes upper and lower surfaces that are substantially parallel to the bottom 1 12 of the processing chamber 100. The support disk 120 is fabricated from a ceramic material, for example aluminum oxide. A first notch 142 is formed in the upper surface of the support disk 120. A second notch 150 is also formed in the upper surface of the support disk 120 opposite the first notch 142. The second notch 150 is radially inward of the first notch 142. In one example, the support disk 120 is a cylindrical ring.

[0022] A sidewall shield 1 16 is disposed in the processing chamber 100 radially inward of the upper liner 106 and the lower liner 108. An upper ring 1 18 is disposed in the processing chamber 100 between the lid 104 and the sidewall shield 1 16. The upper ring 1 18 is supported by the sidewall shield 1 16 and surrounds an opening 152 formed through the lid 104. The upper ring 1 18 is spaced apart from the upper liner 106 to substantially prevent the upper ring 1 18 and the upper liner 106 from locking together. The space therebetween may be, for example, 1 millimeter to 10 millimeters, such as 1 millimeter to 5 millimeters, or 1 millimeter to 3 millimeters. However, other distances are also contemplated. The sidewall shield 1 16 is spaced from the upper liner between 1 millimeter to 10 millimeters, such as 1 millimeter to 5 millimeters, or 1 millimeter to 3 millimeters, or 0.5 millimeters to about 6 millimeters. One or more process gasses may flow into the process volume 1 10 from the lid 104 through the opening 152 and the upper ring 1 18 to process the substrate disposed on the cathode assembly 1 14.

[0023] In some embodiments, which can be combined with one or more embodiments described above, the upper ring 1 18 is fabricated from quarts or a quartz containing material. In some embodiments, which can be combined with one or more embodiments described above, the upper ring 1 18 is fabricated from titanium or a titanium containing material. In some embodiments, which can be combined with one or more embodiments described above, the upper ring 1 18 is part of (e.g., monolithic with) the sidewall shield 1 16. That is, the sidewall shield 1 16 may extend into the opening 152 formed through the lid 104. In some embodiments, which can be combined with one or more embodiments described above, a maximum internal radius of the sidewall shield is between about 250 mm and about 400 mm, for example between about 270 mm and about 300 mm, such as about 275 mm.

[0024] During operation, one or more gasses are flowed through the lid 104 and the opening 152 into the process volume 1 10. An energy source (not shown) provides power to the gasses in the process volume to generate a plasma therein. In some embodiments, which can be combined with one or more embodiments described above, the plasma may be generated in a remote plasma source and flowed to the processing chamber 100. In that case, the plasma is flowed into the processing chamber through the lid 104 and the opening 152.

[0025] In one embodiment, which can be combined with one or more embodiments described above, the sidewall shield 1 16 is a unitary apparatus disposed between the sidewalls 102 of the processing chamber 100. In that case, a thickness of the sidewall shield 1 16 and the cathode shield 122 may be between about 1 mm and about 5 mm, for example, between about 2 mm and about 4 mm, such as about 3 mm. In some examples, to reduce manufacturing costs, the thickness of the sidewall shield 1 16 and the cathode shield 122 may be thinner than about 1 mm. For example, the thickness of the sidewall shield 1 16 and the cathode shield 122 may be between about 0.1 mm and about 0.8 mm, such as about 0.35 mm.

[0026] The sidewall shield 1 16 is cylindrical in shape. The sidewall shield 1 16 is spaced apart from and is not in contact with the upper liner 106 or the lower liner 108. A space between the upper liner 106 and the sidewall shield 1 16 and a space between the lower liner 108 and the sidewall shield 1 16 are discussed below with respect to Figures 3 and 4, respectively. It is contemplated, however, that the sidewall shield 1 16 may contact the upper liner 106 or the lower liner 108 in some examples.

[0027] In some embodiments, which can be combined with one or more embodiments described above, the upper liner 106 and the lower liner 108 may be omitted from the processing chamber 100. In that case, the sidewall shield 1 16 is disposed along the sidewalls 102 of the processing chamber 100. Various dimensions of the sidewall shield 1 16 may be altered to reduce a space between the sidewall shield 1 16 and the sidewalls 102 of the processing chamber 100. For example, an exterior diameter of the sidewall shield 1 16 may be increased to reduce a space between the sidewall shield 1 16 and the sidewalls 102 to reduce the likelihood of parasitic plasma formation.

[0028] A first portion 136 of the sidewall shield 1 16 extends vertically along and is substantially parallel to the sidewalls 102, defining a cylindrical shape. A second portion 138 of the sidewall shield 1 16 extends horizontally along the bottom 1 12 and is substantially normal to the first portion 136. The sidewall shield 1 16 has a filleted edge 140 connecting the first portion 136 and the second portion 138. The second portion 138 of the sidewall shield 1 16 is disposed in the first notch 142 of the support disk 120. In some embodiments, which can be combined with one or more embodiments discussed above, second portion 138 the sidewall shield 1 16 is fastened to the support disk 120 via one or more fasteners (not shown). In some embodiments, which can be combined with one or more embodiments discussed above, the support disk 120 includes one or more alignment keys (described with respect to Figure 4) which correspond to one or more alignment notches (described with respect to Figure 3) formed in the sidewall shield 1 16. The alignment keys and alignment notches enable the ports 126, 128 formed through the shield to be aligned with the ports 126, 128 formed through the upper liner 106 and the sidewalls 102.

[0029] A cathode shield 122 is disposed about the cathode assembly 1 14. The cathode shield 122 circumscribes and encloses at least a portion of the cathode assembly 1 14. The cathode shield 122 is spaced from the cathode assembly 1 14, for example, by about 1 millimeter to about 5 millimeters. A first portion 144 of the cathode shield 122 is substantially parallel to the first portion 136 of the sidewall shield 1 16, and defines a cylinder. A second portion 146 of the cathode shield 122 is substantially normal to the first portion 144. The second portion 146 of the cathode shield 122 is disposed in the second notch 150 of the support disk 120. The cathode shield 122 has a filleted edge 148 connecting the first portion 144 and the second portion 146. In some examples two or more of the cathode shield 122, the support disk 120, and the sidewall shield 1 16 are formed as a single unit (e.g., monolithically).

[0030] Advantageously, the sidewall shield 1 16 and the cathode shield 122 are easily removed from the processing chamber 100 and easily replaced. For example, once the lid 104 is removed from the processing chamber 100, the sidewall shield 1 16 and/or the cathode shield 122 can be lifted from the processing chamber 100 and replaced. To remove the sidewall shield 1 16 from the processing chamber 100, the upper liner 106 and the upper ring 1 18 may also be removed. Easy replacement of the sidewall shield 1 16 and the cathode shield 122 reduces downtime of the processing chamber 100 compared to repairing the sidewall shield 1 16. In one embodiment, as shown, the sidewall shield 1 16 and the cathode shield 122 are separate shields. However, in one embodiment, which can be combined with one or more embodiments described above, the sidewall shield 1 16 and the cathode shield 122 may be a unitary shield. Separation of the sidewall shield 1 16 and the cathode shield 122 into separate shields increases ease of installation of the shields 1 16 and 122.

[0031] In some embodiments, which can be combined with one or more embodiments described above, the sidewall shield 1 16 and the cathode shield 122 are a coating deposited on interior surfaces of the upper liner 106 and the lower liner 108. For example, the sidewall shield 1 16 and the cathode shield 122 are formed in the processing chamber 100 via a deposition process, such as chemical vapor deposition (CVD) or physical vapor deposition (PVD). In some embodiments, which can be combined with one or more embodiments described above, the coating is a titanium containing material. For example, the coating may include titanium, titanium alloys, titanium carbide, titanium oxide, titanium nitride, or combinations thereof. In some embodiments, which can be combined with one or more embodiments described above, the as deposited coating is substantially titanium and then treated in the processing chamber 100 to form titanium carbide, titanium oxide, or titanium nitride. In one embodiment, which can be combined with one or more embodiments described above, a thickness of the sidewall shield 1 16 and the cathode shield 122 coatings is between about 0.1 microns (e.g., micrometers) and about 5 microns, for example between about 1 micron and about 3 microns, such as about 2.5 microns.

[0032] In one embodiment, which can be combined with one or more embodiments described above, the sidewall shield 1 16 and the cathode shield 122 are fabricated from a material having a high density, a high hardness, and a high chemical inertness to a chemistry used to deposit layers on the substrate. For example, the sidewall shield 1 16 and the cathode shield 122 may be fabricated from a titanium containing material, such as titanium, titanium alloys, titanium carbide, titanium oxide, titanium nitride, and combinations thereof.

[0033] While embodiments herein are described with respect to titanium containing sidewall shields 1 16 and cathode shields 122, other materials are also contemplated. In some embodiments, which can be combined with one or more embodiments described above, the sidewall shield 1 16 and the cathode shield 122 are fabricated from a tungsten containing material, a molybdenum containing material, or a platinum containing material. The sidewall shield 1 16 and the cathode shield 122 may be fabricated from a combination of any of the materials described above. In some embodiments, which can be combined with one or more embodiments described above, the sidewall shield 1 16 and the cathode shield 122 are fabricated from different materials.

[0034] In some embodiments, which can be combined with one or more embodiments described above, an outer surface of the sidewall shield 1 16 and the cathode shield 122 are fabricated from the materials discussed above. That is, for example, a portion of the sidewall shield 1 16 and the cathode shield 122 exposed to the plasma formed in the process volume 1 10 are fabricated from a material described above. In some embodiments, which can be combined with one or more embodiments described above, at least the surface of the sidewall shield 1 16 and the cathode shield has at least 99% titanium.

[0035] The sidewall shield 1 16, the cathode shield 122, and the support disk 120 substantially reduce exposure of the sidewalls 102, the upper liner 106, and the lower liner 108 to the plasma formed in the process volume 1 10. Advantageously, a high density, hardness, and chemical inertness of the sidewall shield 1 16 and the cathode shield 122 substantially reduce an occurrence of aluminum contamination of a layer deposited on the substrate disposed on the cathode assembly 1 14. Without the sidewall shield 1 16 and the cathode shield 122 in the processing chamber 100, an amount of aluminum contamination on the substrate increases as an RF power is increased. The titanium containing material used to fabricate the sidewall shield 1 16 and the cathode shield 122 does not generate a substantial amount of titanium contamination of the substrate due to the high density, high hardness, and chemical inertness of the titanium containing material. [0036] A slit valve opening 124, a first port 126, and a second port 128 are formed through the sidewall 102, the upper liner 106, and the sidewall shield 1 16. The second port 128 is disposed opposite the first port 126. As illustrated, the first port 126 and the second port 128 are circular. A diameter of the first port 126 is smaller than a diameter of the second port 128. For example, the diameter of the first port 126 may be about 3 millimeters to about 13 millimeters. A diameter of the second opening may be about 30 millimeters to about 40 millimeters. Other sizes for the first opening 126 and the second opening 128 are also contemplated. During operation, the substrate is transferred into and out of the processing chamber 100 through the slit valve opening 124. A sensor (not shown) may be disposed in the first port 126 (or have visual access therethrough) to measure a characteristic of a layer deposited on the substrate, a characteristic of the plasma formed in the process volume 1 10, or a processing condition, such as temperature or pressure. In some embodiments, which can be combined with one or more embodiments described above, an optical emissions spectroscopy system is positioned to use the first port 126. In one embodiment, which can be combined with one or more embodiments described above, the second port 128 may be used as an optical viewing window.

[0037] Figure 2 is a schematic representation of the sidewall shield 1 16 according to one embodiment. The slit valve opening 124 is formed through the sidewall shield 1 16. An exhaust port 202 is formed through the sidewall shield 1 16 opposite the slit valve opening 124. The exhaust port may circumscribe about 100 degrees to about 160 degrees, such as about 120 degrees to about 150 degrees. The slit valve opening 124 is formed in an upper portion 204 of the sidewall shield 1 16 while the exhaust port 202 is formed in a lower portion 206 of the sidewall shield 1 16. Thus, as shown, the exhaust port 202 and the slit valve opening 124 are disposed on different horizontal planes. However, in some embodiments, which can be combined with one or more embodiments described above, the exhaust port 202 and the slit valve opening 124 may be aligned such that the a major axis of the exhaust port 202 is aligned with a major axis of the slit valve opening 124. In other embodiments, the exhaust port 202 and the slit valve opening 124 may be partially aligned such that a portion of the exhaust port 202 is aligned with the slit valve opening 124.

[0038] A first port 126 and a second port 128 are formed through the upper portion 204 of the sidewall shield 1 16. As shown, the second port 128 is substantially coaxial with the first port 126. In some embodiments, which can be combined with one or more embodiments described above, the first port 126 and the second port 128 may be misaligned vertically or horizontally.

[0039] Figure 3 is a bottom view of the sidewall shield 1 16 according to one embodiment. Figure 4 is a top view of the support disk 120 according to one embodiment. The second portion 138 of the sidewall shield 1 16 extends radially inward. An alignment slot 302 is formed through the second portion 138 of the sidewall shield 1 16. The alignment slot 302 is sized to accommodate an alignment key 402 formed on the support disk 120. The alignment key 402 is illustrated in Figure 4. The alignment key 402 is flush with the support disk 120 and protrudes into the first notch 142.

[0040] In one embodiment, which can be combined with one or more embodiments described above, during processing, the alignment slot 302 is aligned with a central vertical axis of the slit valve opening 124. The alignment slot 302 enables the sidewall shield 1 16 to be positioned in the processing chamber 100 such that the slit valve opening 124 and any other openings (e.g., the exhaust port 202, the first opening 208, and the second opening 210) formed through the chamber and sidewall shield are aligned.

[0041] Figure 5 is an enlarged schematic cross-sectional view of a portion of the processing chamber 100 according to one embodiment. A first space 502 is formed between the upper liner 106 and the sidewall shield 1 16. A width 504 of the first space 502 is between about 2.5 mm and about 8 mm, for example between about 3.5 mm and about 6.4 mm, such as about 4 mm. Other distances, as noted above, are also contemplated. A channel 508 is formed in a surface of the upper ring 1 18 that contact the sidewall shield 1 16. An O-ring 506 is disposed in the channel 508 to create a seal between the upper ring 1 18 and the sidewall shield 1 16. In one embodiment, which can be combined with one or more embodiments described above, the width 504 of the first space 502 is less than 1 mm. For example, the width 504 may be between 0.6 mm to about 0.9 mm, for example between about 0.65 mm and about 0.8 mm. Other distances, as noted above, are also contemplated.

[0042] Figure 6 is a magnified schematic cross-sectional view of another portion of the processing chamber 100 according to one embodiment. A second space 608 is formed between the sidewall shield 1 16 and the lower liner 108. A third space 606 is formed between the cathode assembly 1 14 and the cathode shield 122. A width 610 of the second space 608 is between about 5 mm and about 12 mm, for example between about 7 mm and about 10 mm. In one embodiment, which can be combined with one or more embodiments described above, the width 610 of the second space 608 is less than 1 mm. For example, the width 504 of the second space 608 may be between 0.1 mm to about 0.9 mm, for example between about 0.6 mm and about 0.8 mm. Other distances, as noted above, are also contemplated.

[0043] The first space 502, described with respect to FIG. 5, and the second space 608 are small enough to substantially reduce an occurrence of plasma therein. In some embodiments, which can be combined with one or more embodiments described above, the width 504 of the first space 502 and the width 610 of the second space 608 are substantially the same. In some embodiments, which can be combined with one or more embodiments described above, the width 504 of the first space 502 and the width 610 of the second space 608 are different.

[0044] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

What is claimed is:

1. An apparatus, comprising:

a processing chamber comprising one or more chamber walls, a bottom, and a lid defining a process volume therein;

a cathode assembly disposed in the process volume;

a sidewall shield disposed in the processing chamber surrounding the process volume; and

a cathode shield disposed in the process volume surrounding the cathode assembly, the sidewall shield and the cathode shield comprising titanium.

2. The apparatus of claim 1 , further comprising:

an upper ring disposed between the lid and the sidewall shield; and a support disk disposed at the bottom of the processing chamber, wherein the sidewall shield and the cathode shield are disposed on the support disk.

3. The apparatus of claim 2, wherein a thickness of the sidewall shield is between about 1 mm and about 5 mm.

4. The apparatus of claim 2, wherein the sidewall shield is a coating deposited on an interior surface of the chamber walls, the cathode shield is a coating an external surface of the cathode assembly, and a thickness of the sidewall shield and the cathode shield is between about 0.1 millimeters and about 5 millimeters.

5. The apparatus of claim 2, further comprising:

an alignment key formed in the support disk; and

an alignment slot formed in the sidewall shield sized to accommodate the alignment key therein.

6. The apparatus of claim 1 , wherein a space formed between the sidewall shield and the chamber walls is less than 0.1 mm.

7. An apparatus, comprising:

a cathode assembly disposed in the process volume;

a lower liner disposed in the processing chamber surrounding at least a portion of the cathode assembly;

an upper liner disposed in the processing chamber surrounding at least a portion of the process volume, a portion of the upper liner extending over the lower liner;

a sidewall shield disposed radially inward of the upper liner and the lower liner, the sidewall shield surrounding at least the process volume and at least a portion of the cathode assembly; and

8. The apparatus of claim 7, further comprising:

9. The apparatus of claim 8, wherein a thickness of the sidewall shield is between about 1 mm and about 5 mm.

10. The apparatus of claim 8, wherein the sidewall shield is a coating deposited on an interior surface of the chamber walls, the cathode shield is a coating an external surface of the cathode assembly, and a thickness of the sidewall shield and the cathode shield is between about 0.1 millimeters and about 5 millimeters.

1 1. The apparatus of claim 10, further comprising:

an alignment key formed in the support disk; and an alignment slot formed in the sidewall shield sized to accommodate the alignment key therein.

12. The apparatus of claim 7, wherein a space formed between the sidewall shield and the upper liner is between about 2.5 mm and about 8 mm and a space formed between the sidewall shield and the lower liner is between about 5 mm and about 12 mm.

13. An apparatus, comprising:

a chamber shield comprising a titanium containing material, the chamber shield comprising:

a first portion;

a second portion substantially normal to the first portion; a filleted edge between the first portion and the second portion;

a first port formed through the first portion;

a second port formed through the first portion opposite the first port, and

a slit valve opening formed through the first portion between the first port and the second port; and

an exhaust port formed in the first portion opposite the slit valve opening.

14. The apparatus of claim 13, wherein a thickness of the chamber shield is between about 0.1 mm and about 0.8 mm, a radius of the first port is smaller than a radius of the second port, the first port and the second port are coaxial, and the exhaust port is disposed between the slit valve opening and the second portion.

15. The apparatus of claim 13, wherein the titanium containing material is at least 99 percent titanium.