Top magnets for decreased non-uniformity in pvd

Abstract

A magnet assembly is described, comprising a housing with top plates, each top plate including aligned openings. The housing has a bottom ring and an annular wall, wherein a plurality of openings are formed in the bottom ring. The top plate is on the housing and has a plurality of openings aligned with a plurality of openings in the bottom ring of the housing. The magnet assembly may also include a non-conductive base plate and / or a conductive cover plate. Methods of using the magnet assembly and magnetic field tuning are also described.

Description

Technical Field

[0001] The embodiments disclosed herein generally relate to apparatus and methods for improving the uniformity of physical vapor deposition (PVD). Specifically, the embodiments disclosed herein relate to apparatus and methods for positioning and tuning magnets on top of a PVD chamber. Prior Technology

[0002] Conventional sputtering pre-cleaning using argon (Ar+) ions often results in high film inhomogeneities. This inhomogeneity is particularly prevalent in low-bias-power processes. For example, some silicon oxide processes exhibit inhomogeneities greater than 7% (1σ value), and for TiN, the range is greater than 8 Å.

[0003] Furthermore, under current hardware constraints, the etching rate exhibits a significant center-high / edge-low profile, with the bias voltage decreasing from the center of the substrate towards the edges.

[0004] Current solutions for improving non-uniformity involve optimizing the bias / source ratio, where minimal non-uniformity is observed at approximately 1 (bias power equals source power). However, high-energy Ar+ ions can cause metal resputtering and damage the dielectric film on the substrate.

[0005] Therefore, there is a need in the art for apparatus and methods to improve non-uniformity in etching processes. Summary of the Invention

[0006] One or more embodiments disclosed herein relate to magnet assemblies including a housing having a bottom ring having a top surface and a bottom surface defining a thickness of the bottom ring; an inner diameter having an inner circumferential surface; and an outer diameter having an outer circumferential surface. The bottom ring has a plurality of openings extending through the thickness of the bottom ring, and a housing annular wall extending a height from the top surface of the bottom ring. The housing annular wall has an inner diameter and an outer diameter, the inner diameter having an inner circumferential surface and the outer diameter having an outer circumferential surface, the inner diameter and the outer diameter defining a wall thickness.

[0007] Additional embodiments disclosed herein relate to magnet assemblies, including a base plate, a housing, a top plate, and a cover plate. The base plate has a top surface and a bottom surface that define the thickness of the base plate. The housing is on the base plate. The housing has a bottom ring with a top surface and a bottom surface that define the thickness of the bottom ring; an inner diameter having an inner circumferential surface; and an outer diameter having an outer circumferential surface. The bottom ring has a plurality of openings extending through the thickness of the bottom ring. An annular wall of the housing extends a height from the top surface of the bottom ring. The annular wall of the housing has an inner diameter and an outer diameter, the inner diameter having an inner circumferential surface and the outer diameter having an outer circumferential surface, the inner diameter and the outer diameter defining a wall thickness. The top plate is on the housing. The top plate has a top surface and a bottom surface that define the thickness of the top plate; an inner diameter having an inner circumferential surface; and an outer diameter having an outer diameter surface. The top plate has a plurality of openings extending through its thickness. These openings are aligned with a plurality of openings in the bottom ring of the housing. The cover plate has a top wall and an annular wall. The top wall has a top surface and a bottom surface that define its thickness. The annular wall has an inner diameter and an outer diameter, the inner diameter having an inner diameter surface and the outer diameter having an outer diameter surface, the inner diameter and the outer diameter defining the wall thickness. The annular wall extends a height from the bottom surface of the top wall and has an outer diameter smaller than the inner diameter of the annular wall of the housing. Simple Explanation of the Diagram

[0008] To gain a more detailed understanding of the features described herein, reference can be made to the embodiments for a more specific description of the disclosure, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only typical embodiments of the disclosure and should not be considered as limiting its scope, as the disclosure may allow for other equally effective embodiments.

[0009] Figure 1 is an isometric view of a magnet assembly on top of a physical vapor deposition chamber according to one or more embodiments of the present disclosure;

[0010] Figure 2 shows a partial cross-sectional view of the magnet assembly on top of the physical vapor deposition chamber of Figure 1, taken along line 2-2';

[0011] Figure 3 illustrates an isometric view of a magnet assembly according to one or more embodiments of the present disclosure;

[0012] Figure 4 illustrates an exploded view of a magnet assembly according to one or more embodiments of the present disclosure;

[0013] Figure 5 illustrates an isometric view of a portion of the base plate of a magnet assembly according to one or more embodiments of the present disclosure;

[0014] Figure 6 illustrates an isometric view of a portion of a gasket of a magnet assembly according to one or more embodiments of the present disclosure;

[0015] Figure 7 illustrates an isometric view of a portion of a gasket of a magnet assembly according to one or more embodiments of the present disclosure;

[0016] Figure 8 illustrates an isometric view of the housing of a magnet assembly according to one or more embodiments of the present disclosure;

[0017] Figure 9 illustrates a top view of the housing of a magnet assembly according to one or more embodiments of the present disclosure;

[0018] Figure 10 illustrates an isometric view of the top plate of a magnet assembly according to one or more embodiments of the present disclosure;

[0019] Figure 11 illustrates an isometric view of the cover plate of a magnet assembly according to one or more embodiments of the present disclosure; and

[0020] Figure 12 illustrates a partial cross-sectional view of a magnet assembly according to one or more embodiments of the present disclosure. Implementation

[0021] Before describing several exemplary embodiments of this disclosure, it should be understood that this disclosure is not limited to the details of the construction or processing steps set forth in the following description. This disclosure can have other embodiments and can be practiced or performed in various ways.

[0022] As used in this specification and the appended claims, the term "substrate" refers to a surface or part thereof on which a process is performed. Those skilled in the art will also understand that, unless the context clearly indicates otherwise, reference to a substrate may also refer only to a portion of the substrate. Furthermore, reference to deposition on a substrate may refer to both a bare substrate and a substrate on which one or more films or features are deposited or formed.

[0023] As used herein, "substrate" refers to any substrate or material surface formed on a substrate on which a film treatment is performed during the manufacturing process. For example, depending on the application, substrate surfaces on which treatments can be performed include materials such as silicon, silicon oxide, strained silicon, silicon on insulator (SOI), carbon-doped silicon oxide, amorphous silicon, doped silicon, germanium, gallium arsenide, glass, sapphire, and any other materials such as metals, metal nitrides, metal alloys, and other conductive materials. Substrates include, but are not limited to, semiconductor wafers. Substrates can be exposed to pretreatment processes such as polishing, etching, reduction, oxidation, hydroxylation, annealing, UV curing, electron beam curing, and / or baking of the substrate surface. In addition to performing film treatments directly on the surface of the substrate itself, any of the film treatment steps disclosed in this disclosure can also be performed on an underlayer formed on the substrate, as disclosed in more detail below, and the term "substrate surface" is intended to include such an underlayer as the context suggests.

[0024] According to one or more embodiments, the term "on" in relation to a film or film layer includes a film or layer directly on a surface, such as a substrate surface, and one or more underlying layers between the film or layer and the surface, such as the substrate surface. Therefore, in one or more embodiments, the phrase "on the substrate surface" is intended to include one or more underlying layers. In other embodiments, the phrase "directly on" refers to a layer or film in contact with a surface, such as a substrate surface, without an intermediate layer. Therefore, the phrase "layer directly on the substrate surface" refers to a layer in direct contact with the substrate surface, without any intermediate layers.

[0025] Some embodiments disclosed herein provide apparatus and methods that do not require optimization of the bias / source ratio. The etch profile can be significantly altered by tuning the top magnet. Some embodiments reduce non-uniformity by positioning the magnet at the top of the chamber. A constant external magnetic field can be introduced into the processing chamber to optimize Ar+ ion distribution. The external magnetic field can be adjusted to improve Ar sputtering etch rate non-uniformity (NU%). In exemplary embodiments, the non-uniformity of current methods can be reduced to <4%.

[0026] In some embodiments, the magnet assembly can be installed and optimized (tuned) without opening the processing chamber or changing the configuration of other chambers. The result is that, under a strong magnetic field, the etched profile changes from center-high / edge-low to center-low / edge-high. The number, height, radius, and polarity of the magnets can be adjusted to flatten the profile and improve NU%. In some embodiments, the non-uniformity of known methods is reduced from about 9% to about 2%.

[0027] The hardware components of some embodiments are further discussed below. Typically, a plastic (e.g., nylon) substrate and gaskets hold the top magnetic ring to the chamber cover and allow for height adjustment. A housing, top plate, and cover plate support the magnets. The top plate has holes (e.g., 48) for tuning the number of magnets made of stainless steel to hold them within the aluminum for easy assembly. The magnets are positioned on the top plate by attraction, and other components are held in place by mechanical fasteners (e.g., screws).

[0028] Referring to Figures 1 and 2, one or more embodiments of this disclosure relate to a magnet assembly 100. Specifically, the magnet assembly 100 is configured for use with a physical vapor deposition (PVD) chamber 200. Figure 1 illustrates a portion of the top of a PVD chamber 200 having the magnet assembly 100 according to one or more embodiments of this disclosure. Figure 2 illustrates a partial cross-sectional view of the PVD chamber 200 and a portion of the magnet assembly 100 taken along line 2-2'. The illustrated PVD chamber 200 includes a fan 220 with a fan shroud 230 and an interlock switch 210. The illustrated magnet assembly 100 extends around the fan 220. Although the embodiments of this disclosure are described with respect to a PVD chamber 200, those skilled in the art will recognize that the magnet assembly 100 is not limited to use with a PVD chamber but can be incorporated into other devices employing tunable magnet arrays.

[0029] Figure 3 illustrates an embodiment of a magnet assembly 100, such as those shown in Figures 1 and 2. Figure 4 illustrates an exploded view of the components of the magnet assembly 100 according to one or more embodiments of this disclosure. The magnet assembly 100 shown in Figures 3 and 4 is a generally annular structure with an open interior 101 and includes a base plate 110, gaskets 120, gaskets 130 (as shown in Figure 4), a housing 140, a top plate 160, and a cover plate 150 arranged in a stacked configuration. The illustrated embodiment includes various notches 102 and alignment pins 104 for assembly purposes.

[0030] Figure 5 illustrates a portion of a substrate 110 according to one or more embodiments of the present disclosure. The substrate 110 has a top surface 111 and a bottom surface 112, which define a thickness TB of the substrate 110. The substrate 110 includes an inner diameter having an inner peripheral surface 113 and an outer diameter having an outer peripheral surface 114, which define a width WB of the substrate 110.

[0031] In some embodiments, the base plate 110 includes more than one component. For example, the embodiment shown in the figures has a two-part base plate 110 that can be assembled such that end faces 116 are positioned to touch or nearly touch to form a generally annular base component. The modular base plate of some embodiments allows for easy retrofitting of the magnet assembly 100 to an existing processing chamber, eliminating the need to remove components from the processing chamber during assembly.

[0032] In some embodiments, the base plate 110 comprises at least two portions. For example, two base plates 110, similar to those shown in Figure 5, may be connected to form a single base plate 110. In some embodiments, the base plate 110 comprises three or four parts connected to form a single base plate 110.

[0033] The embodiment shown in Figure 5 includes a connecting flange 118 extending inwardly from the inner peripheral surface 113. The connecting flange 118 provides an area for securing the base plate 110 to the processing chamber using solid fasteners.

[0034] The substrate 110 may have any suitable thickness TB and any suitable width WB. In some embodiments, the thickness TB of the substrate 110 is in the range of 1 / 32 inch to 1 inch (or 1 mm to 25 mm). In some embodiments, the width WB of the substrate 110 is in the range of 1 / 2 inch to 4 inches (or 12 mm to 100 mm).

[0035] The substrate 110 may be made of any suitable material known to those skilled in the art. In some embodiments, the substrate 110 comprises a non-conductive material. In some embodiments, the non-conductive material includes one or more of acetal, polyacetal, polyoxymethylene, nylon, polytetrafluoroethylene (PTFE), polyether ether ketone (PEEK), polycarbonate, or polyvinyl chloride (PVC).

[0036] In some embodiments, the magnet assembly 100 further includes at least one optional spacer 120, 130. Figure 6 illustrates a portion of an optional spacer 120 according to one or more embodiments of the present disclosure. Figure 7 illustrates a portion of an optional second spacer 130 according to one or more embodiments of the present disclosure. Spacers 120, 130 have top surfaces 121, 131 and bottom surfaces 122, 132, which define thicknesses TS1, TS2. Spacers 120, 130 include an inner diameter having inner peripheral surfaces 123, 133 and an outer diameter having outer peripheral surfaces 124, 134, which define widths WS1, WS2 of spacers 120, 130.

[0037] In some embodiments, gaskets 120, 130 include more than one component. For example, the embodiment shown in the figures has two-part gaskets 120, 130, which can be assembled such that end faces 126, 136 are positioned to touch or nearly touch to form a generally annular gasket component. The separable gaskets of some embodiments allow for easy retrofitting of the magnet assembly 100 to an existing processing chamber, eliminating the need to remove components from the processing chamber during assembly.

[0038] In some embodiments, gaskets 120, 130 include at least two portions. For example, two gaskets 120, 130 similar to those shown in Figures 6 and 7 can be joined to form a single gasket 120, 130. In some embodiments, gaskets 120, 130 include three or four parts joined to form a single gasket.

[0039] Gaskets 120 and 130 may be of any suitable thickness TS1 and TS1 and have any suitable width WS1 and WS1. In some embodiments, the thickness TS1 and TS1 of gaskets 120 and 130 are independently in the range of 1 / 32 inch to 1 inch (or 1 mm to 25 mm). In some embodiments, the width WS1 and WS1 of gaskets 120 and 130 are independently in the range of 1 / 2 inch to 4 inches (or 12 mm to 100 mm). In some embodiments, gaskets 120 and 130 have a combined thickness or a single thickness sufficient to lift housing 140 to a suitable height. In some embodiments, no gasket is used between base plate 110 and housing 140. In some embodiments, one gasket 120 is used between base plate 110 and housing 140. In some embodiments, two gaskets 120 and 130 are used between base plate 110 and housing 140. In some embodiments, more than two gaskets are used between base plate 110 and housing 140.

[0040] Gaskets 120 and 130 may be made of any suitable material known to those skilled in the art. In some embodiments, gaskets 120 and 130 independently comprise a non-conductive material. In some embodiments, the non-conductive material includes one or more of acetal, polyacetal, polyoxymethylene, nylon, polytetrafluoroethylene (PTFE), polyether ether ketone (PEEK), polycarbonate, or polyvinyl chloride (PVC).

[0041] Some embodiments of this disclosure relate to a housing 140 or a magnet assembly 100 including a housing 140. Figure 8 illustrates a housing 140 according to one or more embodiments of this disclosure. Figure 9 illustrates a top view of a housing 140 according to one or more embodiments of this disclosure. In some embodiments, the housing 140 is a generally annular component having an open interior 141. In some embodiments, the housing 140 is located on a base plate 110 and is in direct contact with the base plate 110 or with one or more intermediate gaskets 120, 130.

[0042] The housing 140 has a bottom ring 142 having a top surface 143 and a bottom surface 144, which define the thickness T BR of the bottom ring 142. The bottom ring 142 has an inner diameter with an inner circumferential surface 144 and an outer diameter with an outer circumferential surface 145, which define the width W BR of the bottom ring 142. In some embodiments, the thickness T BR of the bottom ring 142 is in the range of 1 / 16 inch to 1 / 4 inch (or 1.5 mm to 6 mm). In some embodiments, the width W BR of the bottom ring 142 is in the range of 1 inch to 4 inches (or 25 mm to 100 mm).

[0043] The bottom ring 142 has a plurality of openings 146 extending through the thickness T BR of the bottom ring 142. In some embodiments, the openings 146 extend a distance from the top surface 143 of the bottom ring 142 through a portion of the thickness T BR of the bottom ring 142.

[0044] The plurality of openings 146 in the housing are arranged in sets 147. Each set 147 of openings 146 is aligned along a vector V BR extending from the center 148 of the bottom ring 142 to the outer peripheral surface 145. Each opening in the set of openings is located at a different distance from the center 148 to form a ring of openings 146 with different radii or diameters.

[0045] Each set 147 of openings 146 may have any suitable number of openings aligned along vector V BR. In the illustrated embodiment, each set 147 has three openings 146. In some embodiments, each set 147 has three openings 146, thereby forming three loops of openings 146 around a center 148, each loop having a different radius from the center 148. In some embodiments, each set 147 includes two or more openings 146. In some embodiments, each set 147 includes an range of two to five openings 146.

[0046] The number of sets 147 of openings 146 arranged around the center 148 can vary. In some embodiments, there are sets 147 of openings 146 ranging from 6 to 120. In some embodiments, there are sets 147 of openings 146 ranging from 12 to 80, or sets 147 of openings 146 ranging from 24 to 60.

[0047] The housing 140 includes an annular wall 150 extending from the top surface 143 of the bottom ring 142 by a height H AW. The annular wall 150 has an inner diameter with an inner circumferential surface 151 and an outer diameter with an outer circumferential surface 152, the inner and outer diameters defining a wall thickness T AW. In some embodiments, the thickness T AW of the annular wall 150 is in the range of 1 / 16 inch to 1 / 4 inch (or 1.5 mm to 6 mm). In some embodiments, the height H AW of the annular wall 150 is in the range of 0.5 inch to 2.5 inch (or 12 mm to 62 mm).

[0048] In some embodiments, housing 140 includes a top flange 155 located on top of annular wall 150. In some embodiments, top flange 155 extends outward from outer peripheral surface 152 of annular wall 150. In some embodiments, top flange 155 extends outward to outer peripheral surface 157 having the same diameter as bottom ring 142. In some embodiments, the thickness T TF of top flange 155 defined between top surface 156 and bottom surface 158 of top flange 157 is in the range of 1 / 16 inch to 1 / 4 inch (or 1.5 mm to 6 mm).

[0049] In some embodiments, as shown, the bottom ring 142 and / or the top flange 155 have truncated portions that form flat portions 159 on the outer peripheral surfaces 145, 157. In some embodiments, at least one truncated portion is present that forms at least one flat portion 159. In some embodiments, the flat portion 159 is sized to allow the housing 140 to be fitted near another component on the processing chamber (e.g., the interlock switch 210 shown in Figure 1).

[0050] The housing 140 may be made of any suitable material. In some embodiments, the housing 140 comprises a conductive material. In some embodiments, the housing 140 comprises one or more of aluminum or stainless steel.

[0051] In some embodiments, the magnet assembly 100 includes a top plate 160. Figure 10 illustrates a top plate 160 according to one or more embodiments of the present disclosure. In some embodiments, the top plate 160 is located on an annular wall 150 of the housing 140. In some embodiments, the top plate 160 is located on a top flange 155 of the housing 140.

[0052] The top plate 160 is a generally annular component with an open interior 161. The top plate 160 has a top surface 162 and a bottom surface 163, which define the thickness T TP of the top plate 160. The top plate 160 has an inner diameter with an inner circumferential surface 164 and an outer diameter with an outer diameter surface 165, which define the width W TP of the top plate 160.

[0053] The top plate 160 has a plurality of openings 166 extending through the thickness T TP of the top plate 160. In some embodiments, the openings 166 extend partially through the thickness T TP of the top plate 160 from the bottom surface 163 to form a groove in the bottom surface 163. In some embodiments, the thickness T TP of the top plate 160 is in the range of 1 / 16 inch to 1 / 4 inch (or 1.5 mm to 6 mm).

[0054] The plurality of openings 166 are aligned with a plurality of openings 146 in the bottom ring 142 of the housing 140. In some embodiments, the plurality of openings 166 are arranged in a set 167 to be aligned with a set 147 of openings 146 in the housing 140.

[0055] A plurality of openings 166 in the top plate 160 are arranged in a set 167. Each set 167 of openings 166 is aligned along a vector V TP extending from the center 168 of the top plate 160 to the outer peripheral surface 165. Each opening 166 in the set 167 is located at a different distance from the center 168 to form a loop of openings 166 with different radii or diameters.

[0056] Each set 167 of openings 166 may have any suitable number of openings aligned along vector V TP. In the illustrated embodiment, each set 167 has three openings 166. In some embodiments, three openings 166 in each set 167 form three loops of openings 166 around a center 168, each loop having a different radius from the center 168. In some embodiments, each set 167 includes two or more openings 166. In some embodiments, each set 167 includes two to five openings 166.

[0057] The number of sets 167 of openings 166 arranged around the center 168 can vary. In some embodiments, there are sets 167 of openings 166 ranging from 6 to 120. In some embodiments, there are sets 147 ranging from 12 to 80, or sets 167 of openings 166 ranging from 24 to 60.

[0058] In some embodiments, as shown, the top plate 160 has a truncated portion that forms a flat portion 169 on the outer peripheral surface 165. In some embodiments, at least one truncated portion is present, which forms at least one flat portion 169. In some embodiments, the flat portion 169 is sized to allow the top plate 160 to be fitted near another component on the processing chamber (e.g., the interlock switch 210 shown in Figure 1).

[0059] The top plate 160 may be made of any suitable material. In some embodiments, the top plate 160 comprises a conductive material. In some embodiments, the top plate 160 comprises one or more of aluminum or stainless steel.

[0060] Some embodiments of the magnet assembly 100 include a cover plate 180. Figure 11 illustrates a cover plate 180 according to one or more embodiments of the present disclosure. The cover plate 180 is a generally annular component having an open interior 181. The cover plate 180 has a cover plate top wall 182 having a top surface 183 and a bottom surface 184 defining a thickness T CP of the cover plate top wall 182. In some embodiments, the thickness T CP of the cover plate 180 is in the range of 1 / 16 inch to 1 / 4 inch (or 1.5 mm to 6 mm).

[0061] The cover annular wall 190 has an inner diameter with an inner diameter surface 191 and an outer diameter with an outer diameter surface 192, the inner diameter and the outer diameter defining the annular wall thickness T CAW. The cover annular wall 190 extends a height H CP from the bottom surface 184 of the cover top wall 182 and has an outer diameter surface 192, the outer diameter of which is smaller than the inner diameter of the inner circumferential surface 151 of the housing annular wall 150. In some embodiments, the thickness T CAW of the annular wall 190 is in the range of 1 / 16 inch to 1 / 4 inch (or 1.5 mm to 6 mm).

[0062] The cover plate 180 may be made of any suitable material. In some embodiments, the cover plate 180 comprises a conductive material. In some embodiments, the cover plate 180 comprises one or more of aluminum or stainless steel.

[0063] In some embodiments, as shown, the cover 180 has a truncated portion that forms a flat portion 189 on the outer peripheral surface 185. In some embodiments, at least one truncated portion is present, which forms at least one flat portion 189. In some embodiments, the flat portion 189 is sized to allow the cover 180 to be fitted near another component on the processing chamber (e.g., the interlock switch 210 shown in Figure 1).

[0064] Some embodiments of the magnet assembly 100 include one or more magnets 195. Figure 12 illustrates a partial cross-sectional view of the magnet assembly 100 according to one or more embodiments of the present disclosure. In some embodiments, each set 147 of openings 146 in the housing 140 has a magnet 195. In some embodiments, there are fewer magnets 195 than the set 147 of openings 146 in the housing 140. In some embodiments, the magnets 195 are located between the housing 140 and the top plate 160 such that each magnet 195 is aligned with openings 146, 166 in the housing 140 and the top plate 160. In some embodiments, the magnet 195 includes a top protrusion 196 and a bottom protrusion 197, which are respectively fitted into openings 166 and 146.

[0065] When assembled, as shown in Figure 12, according to some embodiments, the bottom 186 of the cover 180 is spaced 187 from the top surface 121 of the gasket 120 (or, if the gasket 120 is absent, the top surface 111 of the base plate 110). In some embodiments, the distance 187 is in the range of 0.01 inches to 0.1 inches (or 0.25 mm to 2.5 mm). In some embodiments, when assembled, the outer peripheral surface 182 of the cover 180 is spaced from the inner peripheral surface 144 of the housing 140 by a distance in the range of 0.005 inches to 0.05 inches (or 0.125 mm to 1.25 mm). In some embodiments, the magnet assembly 100 is held together using one or more physical connectors 194 (e.g., bolts or screws).

[0066] Throughout this specification, references to "one embodiment," "some embodiments," "one or more embodiments," or "an embodiment" mean that a particular feature, structure, material, or characteristic described in connection with that embodiment is included in at least one embodiment of this disclosure. Therefore, the appearance of terms such as "in one or more embodiments," "in some embodiments," "in one embodiment," or "in one embodiment" throughout this specification does not necessarily refer to the same embodiment of this disclosure. Furthermore, in one or more embodiments, a particular feature, structure, material, or characteristic may be combined in any suitable manner.

[0067] Although the disclosure herein has been described with reference to specific embodiments, those skilled in the art will understand that the described embodiments are merely illustrative of the principles and applications of this disclosure. It will be apparent to those skilled in the art that various modifications and variations can be made to the methods and apparatus disclosed herein without departing from the spirit and scope of this disclosure. Therefore, this disclosure may include modifications and variations within the scope of the appended claims and their equivalents.

[0068] 2-2': Line 100: Magnet assembly 101: Open Interior 102: Notch 104: Alignment pin 110: Base plate 111: Top surface 112: Bottom surface 113: Inner circumferential surface 114: Outer Peripheral Surface 116: End face 118: Connecting flange 120: Gasket 121: Top surface 122: Bottom surface 123: Inner circumferential surface 124: Outer Peripheral Surface 126: End face 130: Gasket 131: Top surface 132: Bottom surface 133: Inner circumferential surface 134: Outer Peripheral Surface 136: End face 140: Casing 141: Open interior 142: Bottom ring 144: Inner circumferential surface 146: Opening 150: Annular wall of the shell 155: Top flange 159: Flat area 160: Top plate 161: Open interior 162: Top surface 163: Bottom surface 164: Inner circumferential surface 165: Outer diameter surface 166: Opening 167: Set 168: Center 169: Flat area 180: Cover plate 181: Open interior 182: Top wall of the cover plate 183: Top surface 184: Bottom surface 185: Outer Peripheral Surface 186: Bottom 187: Distance 189: Flat section 190: Cover plate annular wall 191:Inner diameter surface 192: Outer diameter surface 194: Physical Connector 195: Magnet 196: Top protrusion 197: Bottom protrusion 200: PVD chamber 210: Interlock switch 220: Fan 230: Fan Cover H CP: Altitude TB: Thickness T CAW: Annular wall thickness TCP: Thickness T S1: Thickness T S2: Thickness TTP: Thickness V TP: Vector WB: Width W S1: Width W S2: Width WTP: Width

[0069] Domestic storage information (please note in order of storage institution, date, and number) none Overseas storage information (please note in the order of storage country, institution, date, and number) none

Claims

1. A magnet assembly, comprising: A housing having a bottom ring having a top surface and a bottom surface defining a thickness of the bottom ring; an inner diameter having an inner circumferential surface; and an outer diameter having an outer circumferential surface, the bottom ring having a plurality of openings extending through the thickness of the bottom ring; and a housing annular wall extending a height from the top surface of the bottom ring, the housing annular wall having an inner diameter and an outer diameter, the inner diameter having an inner circumferential surface and the outer diameter having an outer circumferential surface, the inner diameter and the outer diameter defining a wall thickness; and a top flange on a top of the housing annular wall, the top flange extending outward from the outer circumferential surface of the housing annular wall.

2. The magnet assembly as claimed in claim 1, wherein the plurality of openings are arranged in an assembly, each assembly being aligned along a vector extending from a center of the bottom ring to the outer peripheral surface, and each hole in each assembly being located at a different distance from the center.

3. The magnet assembly as claimed in claim 2, wherein each set of holes has three holes, thereby forming three rings around the central hole, each ring having a different radius from the center.

4. The magnet assembly as described in claim 2, wherein there is an array of holes ranging from 24 to 60.

5. The magnet assembly as claimed in claim 1, wherein the bottom ring has a truncated portion, thereby forming a flat portion on the outer peripheral surface.

6. The magnet assembly as claimed in claim 1, wherein the height of the annular wall of the housing is in the range of 0.5 inches to 2.5 inches.

7. The magnet assembly as claimed in claim 1, wherein the housing comprises aluminum.

8. The magnet assembly as claimed in claim 1, wherein the thickness of the bottom ring and the wall thickness of the annular wall are in the range of 1 / 16 inch to 1 / 4 inch.

9. A magnet assembly, comprising: A base plate having a top surface and a bottom surface defining a thickness of the base plate; a housing having a bottom ring having a top surface and a bottom surface defining a thickness of the bottom ring; an inner diameter having an inner circumferential surface; and an outer diameter having an outer circumferential surface, the bottom ring having a plurality of openings extending through the thickness of the bottom ring; and a housing annular wall extending a height from the top surface of the bottom ring, the housing annular wall having an inner diameter and an outer diameter, the inner diameter having an inner circumferential surface and the outer diameter having an outer circumferential surface, the inner diameter and the outer diameter defining a wall thickness; A top plate on the housing, the top plate having a top surface and a bottom surface, the top surface and the bottom surface defining a thickness of the top plate; and an inner diameter and an outer diameter, the inner diameter having an inner circumferential surface and the outer diameter having an outer diameter surface, the top plate having a plurality of openings extending through the thickness of the top plate, the plurality of openings being aligned with a plurality of openings in the bottom ring of the housing; and a cover plate having a cover plate top wall and a cover plate annular wall, the cover plate top wall having a top surface and a bottom surface, the top surface and the bottom surface defining a thickness of the cover plate top wall, the cover plate annular wall having an inner diameter and an outer diameter, the inner diameter having an inner diameter surface and the outer diameter having an outer diameter surface, the inner diameter and the outer diameter defining a wall thickness, the cover plate annular wall extending a height from the bottom surface of the cover plate top wall and having an outer diameter smaller than the inner diameter of the housing annular wall.

10. The magnet assembly as claimed in claim 9, wherein the plurality of openings in the housing are arranged in an assembly, each assembly being aligned along a vector extending from a center of the bottom ring to the outer peripheral surface, each hole of each assembly being located at a different distance from the center, and the plurality of openings in the top plate are arranged in an assembly, the assemblies being aligned with the assemblies in the housing.

11. The magnet assembly as claimed in claim 10, wherein each set of holes has three holes, thereby forming three rings around the central hole, each ring having a different radius from the center.

12. The magnet assembly as claimed in claim 10, wherein there is an array of holes ranging from 24 to 60.

13. The magnet assembly as claimed in claim 10, wherein the height of the annular wall is in the range of 0.5 inches to 2.5 inches.

14. The magnet assembly as claimed in claim 9, wherein the base plate comprises at least two portions that, when assembled, form an annular base plate.

15. The magnet assembly as claimed in claim 9, wherein the base plate comprises a non-conductive material, the housing comprises aluminum, the top plate comprises stainless steel, and the cover plate comprises aluminum.

16. The magnet assembly as claimed in claim 9, further comprising at least one gasket located between the base plate and the housing.

17. The magnet assembly as claimed in claim 16, wherein each of the at least one gasket comprises at least two portions that, when assembled, form an annular gasket.

18. The magnet assembly as claimed in claim 16 further includes a top flange on a top of the annular wall, the top flange extending outward from the outer periphery of the annular wall.

19. The magnet assembly as claimed in claim 9, further comprising a plurality of magnets located between the housing and the top plate, each of the magnets being located within an aligned opening in the housing and the top plate.

Images