Rotating Electrical Feedthrough Integration for a Process Chamber

Abstract

The embodiments disclosed herein include semiconductor processing tools. In one embodiment, a semiconductor processing tool includes a chamber, a chuck within the chamber configured to rotate, a pedestal holder around the chuck, and a utility column coupled to the chuck. In one embodiment, the utility column includes a magnetic coupler to enable rotation of the utility column and portions of the chuck, and a rotary electrical feedthrough.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims priority to U.S. Patent Application No. 17 / 865,255, filed on July 14, 2022, the entire content of which is incorporated herein by reference.

[0002] Embodiments relate to the field of semiconductor manufacturing, and more particularly, to a semiconductor processing tool having a rotational electrical feed - through to enable rotation of a substrate within the semiconductor processing tool.

Background Art

[0003] In semiconductor manufacturing processes, process uniformity is an important metric. In the case of deposition processes such as physical vapor deposition (PVD) processes, the uniformity metric of interest is the thickness uniformity of the deposited film. Currently, there are many different process control variables that can be adjusted to attempt to improve thickness uniformity. Unfortunately, such controls (e.g., RF power, gas flow rate, temperature, etc.) for a stationary wafer do not provide the necessary improvements required for advanced processing operations.

[0004] Therefore, it may be desirable to introduce a rotating component into a semiconductor processing tool. Rotating a substrate (e.g., a wafer) can strip thickness variations and result in averaging to provide a more uniform thickness value across the surface of the substrate. However, adding rotation to a semiconductor processing tool is not without problems. For example, existing chucking architectures may require the use of electrical inputs. Therefore, a way to rotate the electrical inputs is needed. Further, providing a rotational force to the chuck can result in an architecture that cannot maintain a high - vacuum state (e.g., 1e -9 Torr or less).

Summary of the Invention

[0005] The embodiments disclosed herein include semiconductor processing tools. In one embodiment, the semiconductor processing tool includes a chamber, a chuck within the chamber configured to rotate, a pedestal holder around the chuck, and a utility column coupled to the chuck. In one embodiment, the utility column includes a magnetic coupler to enable rotation of the utility column and a portion of the chuck, and a rotary electrical feedthrough.

[0006] The embodiments disclosed herein include rotary electrical feedthroughs. In one embodiment, the rotary electrical feedthrough includes a stator housing, an electrical transmission assembly within the stator housing, a first insulator between the electrical transmission assembly and the stator housing, a rotor electrically coupled to the electrical transmission assembly, a mechanical bearing between the rotor and the stator housing, and a second insulator between the mechanical bearing and the stator housing.

[0007] The embodiments disclosed herein include magnetic couplers to enable non - contact rotation. In one embodiment, the magnetic coupler includes a tube, a bushing around the tube, a housing outside the bushing, a first set of magnets between the tube and the bushing, a second set of magnets between the bushing and the housing, a first bearing between the tube and the bushing that is electrically insulated, and a second bearing between the bushing and the housing.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 3C

Figure 4

DETAILED DESCRIPTION OF THE INVENTION

[0009] The systems described herein include semiconductor processing tools having a rotary electrical feedthrough to enable rotation of a substrate within the semiconductor processing tool. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments. It will be apparent to one of ordinary skill in the art that the embodiments may be practiced without these specific details. In other instances, well-known aspects are not described in detail so as not to obscure the embodiments unnecessarily. Further, it should be understood that the various embodiments shown in the accompanying drawings are illustrative representations and are not necessarily drawn to scale.

[0010] As described above, it is desirable to provide a rotational motion to a substrate in a semiconductor processing tool. The rotational motion enables improved parameter uniformity, such as thickness uniformity. However, existing rotational architectures are limited in that they may not provide a proper vacuum pressure environment and adaptation for the utilities (e.g., electrical and gas paths) that need to be connected to the chuck.

[0011] Accordingly, embodiments disclosed herein include semiconductor processing tools with high-speed rotating components. In one example, an embodiment includes a magnetic coupling portion that enables rotation outside a vacuum environment to be transmitted to components within the vacuum environment. Accordingly, a low-pressure environment can be maintained. Further, embodiments include a rotating electrical feedthrough that enables utilities to the chuck to rotate freely. For example, in some embodiments, up to seven or more electrical paths can be provided through the rotating electrical feedthrough.

[0012] Furthermore, embodiments disclosed herein enable a highly efficient RF return path. This enables closed-loop control of the plasma circuit, and this return path provides a connection between the chamber ground shield and the inner ground surface of the feedthrough connector, ultimately leading to an RF match / power supply in the atmosphere and realizing the circuit loop. Specifically, the RF return path is electrically insulated from other conductive components (e.g., using an insulating layer, insulating bearings, etc.) to improve the efficiency of the RF return path.

[0013] Referring now to FIG. 1, a schematic diagram of a semiconductor processing tool 100 according to one embodiment is shown. The semiconductor processing tool 100 can be any type of tool useful in a semiconductor manufacturing process. For example, the semiconductor processing tool 100 can be a deposition tool (e.g., a chemical vapor deposition (CVD) tool, a physical vapor deposition (PVD) tool, an atomic layer deposition (ALD) tool, etc.) or an etching tool. The semiconductor processing tool 100 can include a chamber 110. The chamber 110 is shown as a single structure in FIG. 1 for simplicity, but it should be understood that the chamber 110 can include any number of individual components. In one embodiment, a baffle 111 can be used to enable vertical displacement of the chuck 105.

[0014] In one embodiment, chuck 105 may support substrate 115. Substrate 115 may be any suitable substrate, such as a silicon wafer or other semiconductor wafer. That being said, substrate 115 formed of other materials (e.g., glass, ceramic, etc.) may also be processed in semiconductor processing tool 100. Substrate 115 may have any suitable form factor (e.g., 300 mm wafer, 450 mm wafer, other standard wafer form factors, or any non-wafer form factor).

[0015] In one embodiment, chuck 105 may include heaters 117 and 118. The heaters may be separated into an inner heater 117 and an outer heater 118. Chuck 105 may also be an electrostatic chuck (ESC). In such an embodiment, chuck 105 may include features for applying an electrostatic force to substrate 115. For example, electrodes 116 may be provided within chuck 105. Electrodes 116 may include a left electrode, a right electrode, and a center tap. In one embodiment, electrical connections 135 for heaters 117 and 118 and electrodes 116 may be provided through utility column 113. Electrical path 135 may include connections for RF power, AC power, and / or DC power.

[0016] The ends of electrical connections 135 may be provided at input 132 of rotary electrical feedthrough 130. Rotary electrical feedthrough 130 takes fixed electrical input 132 and routes fixed electrical input 132 to rotor 131, which is rotatable. As shown in FIG. 1, chuck 105, magnetic coupler 120, and rotor 131 are all shown with the same shading to indicate that they are part of the rotational system of semiconductor processing tool 100. The rotational force may be supplied by magnetic system 122. The rotational system will be described in more detail below.

[0017] In one embodiment, the backside gas conduit 119 is also provided through the utility column 113 and the rotary electrical feedthrough 130. For example, a dynamic seal (not shown) may be provided at the bottom of the rotary electrical feedthrough 130 to enable rotation around the backside gas conduit 119. The backside gas conduit 119 can be axially centered with the utility column 113. This enables the chuck 105, the magnetic coupler 120, and the rotary electrical feedthrough 130 to rotate freely about the fixed backside gas conduit 119.

[0018] In one embodiment, the structure of the semiconductor processing tool 100 may further include an RF return path 101. The RF return path 101 enables closed-loop control of the plasma circuit. In certain embodiments, the RF return path 101 is provided along fixed conductive features in the utility column 113 and the rotary electrical feedthrough 130. For example, the RF return path 101 may originate at the fixed pedestal holder 112. The pedestal holder 112 may be coupled to a chamber ground shield (not shown) with a conductive strap. The conductive strap is flexible to enable electrical connection to be maintained when the vertical position of the chuck 105 is changed within the chamber 100. In one embodiment, the pedestal holder 112 may be electrically coupled to the utility column 113. Thus, the RF return path 101 may pass along the fixed portion of the utility column 113 until it reaches the rotary electrical feedthrough 130. The RF return path 101 continues on the fixed outer housing of the rotary electrical feedthrough 130. As will be described in more detail below, the RF return path 101 may be electrically isolated from other conductive features of the semiconductor processing tool 100. Thus, there is minimal interference with the RF return path 101.

[0019] Also, it should be understood that the rotating mechanism (i.e., magnetic rotation) enables a high-vacuum state. Specifically, the magnetic coupler and the rotary electrical feedthrough 130 may include an internal volume that remains below the vacuum pressure within the chamber 110. In certain embodiments, the pressure in the rotary electrical feedthrough 130 is decreased to push the state to the left end of the Paschen curve in order to prevent ignition of the plasma within the rotary electrical feedthrough 130.

[0020] Next, referring to FIG. 2, a cross-sectional view of a magnetic coupler 220 according to one embodiment is shown. In one embodiment, the magnetic coupler 220 may include a bushing 240. The bushing 240 may be a fixed component within the semiconductor processing tool 100. For example, the bushing 240 may be bolted or otherwise coupled to a chamber (not shown) and a rotary electrical feedthrough (not shown). O-rings 245 and 246 may be provided at the interface with other components. The O-ring 245 provides a seal for maintaining the vacuum pressure within the bushing 240 against the external atmospheric pressure.

[0021] In one embodiment, the bushing 240 may comprise a conductive material such as metal. The conductive material may be used as part of the electrical path of the RF return path 101 described in more detail above. Specifically, the RF return path 101 may follow the inner surface of the bushing 240. Further, since magnetic force is used to enable rotation of the system, the bushing 240 is a non-magnetic conductor. For example, the bushing 240 may comprise aluminum or the like.

[0022] In one embodiment, the tube 241 can be provided inside the bushing 240. The tube 241 can be an enclosure around a utility (not shown) passing through the magnetic coupler 220. The interior of the tube 241 can be configured to be maintained at a vacuum pressure in some embodiments. In one embodiment, the tube 241 can be mechanically coupled to one or more first magnets 243. The first magnet 243 can be provided inside the bushing 240. In certain embodiments, six or more first magnets 243 can be provided axially around the inside of the bushing 240. The first magnet 243 can be mechanically coupled to the tube 241 such that movement of the first magnet 243 causes movement of the tube 241.

[0023] In one embodiment, the tube 241 can interface with the bushing 240 via a bearing 247. The bearing 247 can be provided above and / or below the first magnet 243. The bearing 247 enables smooth movement of the tube 241 with respect to the bushing 240. In certain embodiments, the bearing 247 is an insulating bearing 247 that electrically insulates. Electrically insulating the bearing 247 helps the efficiency of the RF return path 101 passing along the inner surface of the bushing 240. If the bearing 247 is conductive, the RF return path 101 can be degraded because the bearing 247 directly contacts the RF return path 101. For example, the non-conductive bearing 247 can include a ceramic bearing or the like. In one embodiment, the bearing 247 can be configured for use in a vacuum environment.

[0024] In one embodiment, an outer housing 242 may be provided around the bushing 240. The outer housing 242 may be rotatable about the bushing 240. For example, a bearing 248 may be provided between the outer housing 242 and the bushing 240. In one embodiment, the bearing 248 can be any type of bearing. Specifically, since the bearing 248 does not contact the inner surface of the bushing 240, there is no concern that the conductive bearing 248 interferes with the RF return path 101. Further, the bearing 248 is provided in an atmospheric state, as opposed to the vacuum state in which the bearing 247 is exposed.

[0025] In one embodiment, a plurality of second magnets 244 are provided between the outer housing 242 and the bushing 240. The number of the second magnets 244 may match the number of the first magnets 243. Specifically, each first magnet 243 may be magnetically coupled to a different one of the second magnets 244. The second magnets 244 may also be mechanically coupled to the outer housing 242. Thus, when the outer housing 242 rotates, the second magnets 244 will also rotate. Further, the rotation of the second magnets 244 will cause the rotation of the first magnets 243 and the tube 241. In some embodiments, the tube 241 may be mechanically coupled to the chuck 105 and the rotating component (e.g., the rotor) of the rotary electrical feedthrough 130. Thus, the rotation of the outer housing 242 causes the desired rotation of the system. In one embodiment, the outer housing 242 may be coupled to an actuator (not shown) or the like. The actuator may be used to enable the rotation of the outer housing 242.

[0026] Next, referring to FIG. 3A, a cross-sectional view of a rotary electrical feedthrough 330 according to one embodiment is shown. Further, for context, the lower portion of the bushing 340 of the magnetic coupler 320 is shown. The bottom of the bushing 340 may be coupled to a stationary outer housing 351 (which may be referred to as the stator housing 351). An O-ring 346 or other gasket material may be used to provide a vacuum seal between the bushing 340 and the stator housing 351. Bolts 338 or other fasteners may fix the bushing 340 to the stator housing 351.

[0027] In one embodiment, the stator housing 351 may include a feedthrough or input 332. The input 332 may be sealed so that a vacuum can be maintained in the volume 358 inside the stator housing 352. The input 332 may be suitable for any type of power or signal (e.g., RF, AC, and / or DC). In certain embodiments, the input 332 may include, for example, an HN connector. The input 332 allows the signal 335 to pass from outside the vacuum environment to the inside of the vacuum in the volume 358 of the rotary electrical feedthrough 330. In some embodiments, multiple inputs 332 are provided. For example, in some embodiments, up to seven or more electrical inputs 332 may be provided.

[0028] In one embodiment, a bridge 364 may connect the input 332 to the electrical transmission assembly 353. The electrical transmission assembly 353 allows the stationary input 332 to rotate freely. The electrical transmission assembly 353 may include any architecture suitable for providing a rotational function to the stationary input 332. For example, the electrical transmission assembly 353 may be a slip ring, brush, liquid metal interconnect, or roll ring architecture. The output 354 may be directly coupled to the rotor 355.

[0029] The rotor 355 can be mechanically coupled to the connector 339, and the connector 339 extends into the magnetic coupler 320. For example, the connector 339 can be coupled to the rotating inner tube 241. That is, the rotation in the magnetic coupler 320 can be transmitted through the connector 339 to the rotary electrical feed-through 330. In one embodiment, the rotor 355 can be coupled to the stator housing 351 by a bearing 356 that allows free rotation of the rotor 355 inside the stator housing 351.

[0030] As described above, the interior 357 and the internal volume 358 of the magnetic coupler 320 can be maintained at a vacuum pressure. In some embodiments, the interior 357 of the magnetic coupler 320 can be fluidly coupled to the internal volume 358 such that the two are maintained at substantially the same pressure. (More details will be described below) In other embodiments, there can be a pressure difference between the interior 357 and the internal volume 358 of the magnetic coupler 320.

[0031] The illustrated embodiment also shows the path of the RF return path 301. As shown, the RF return path 301 is provided along the inner surface of the bushing 340 and continues on the inner surface of the stator housing 351. The RF return path 301 can follow the interior of the stator housing 351 until it reaches one of the inputs 332. The RF ground path 301 can then be propagated out of the vacuum environment and connected to an RF match / power supply (not shown) to complete the RF circuit to enable closed-loop control of the plasma.

[0032] Referring now to FIG. 3B, a cross-sectional view of the rotary electrical feed-through 330 according to an additional embodiment is shown. In one embodiment, the rotary electrical feed-through 330 in FIG. 3B can be substantially similar to the rotary electrical feed-through 330 in FIG. 3A, except for the RF return path 301. As described above, the presence of conductive features along the RF return path 301 can degrade the effectiveness of the return path. Therefore, provisions are made to avoid the presence of conductive material along the return path 301.

[0033] For example, the bearing 356 can be separated from the inner surface of the stator housing 351 by an insulating liner 361. The insulator liner 361 can be any electrically insulating material such as plastic, rubber, etc. When the insulating liner 361 is present, the bearing 356 can be any type of bearing 356 including a conductive bearing 356. In some embodiments, the insulating liner 361 can be an integral part of the bearing 356, or the insulating liner 361 can be an individual component between the bearing 356 and the stator housing 351. In yet another embodiment, the bearing 356 can be an insulating bearing 356 such as a ceramic bearing 356. In such embodiments, an individual insulating liner 361 may not be necessary.

[0034] Furthermore, in some cases, the surface of the electrical transmission assembly 353 can be conductive. In such embodiments, an insulating liner 362 can be provided between the electrical transmission assembly 353 and the stator housing 351. When both the bearing 356 and the electrical transmission assembly 353 are electrically insulated from the stator housing 351, the RF return path 301 is improved.

[0035] Referring next to FIG. 3C, a cross-section of a rotary electrical feedthrough 330 according to an additional embodiment is shown. In one embodiment, the rotary electrical feedthrough 330 in FIG. 3C can be substantially similar to the rotary electrical feedthrough 330 in FIG. 3B, except for the interface between the rotary electrical feedthrough 330 and the magnetic coupler 320.

[0036] Rather than two components being fluidly coupled to each other, the interior 357 of the magnetic coupler 320 can be separated from the interior volume 358 of the rotary electrical feedthrough 330. For example, an O-ring 336 etc. can be provided between the connector 339 and the bushing 340. In certain embodiments, the O-ring 336 is a dynamic seal that allows the connector 339 to rotate.

[0037] Separating the two volumes 357 and 358 allows volume 358 to be maintained at a pressure different from that of volume 357. For example, the pressure in the inner volume 358 can be lower than the pressure of volume 357. For example, the pressure in volume 357 can be 1e -6 Torr, and the pressure in the inner volume 358 can be 1e -9 Torr. In certain embodiments, a dedicated pump (not shown) can be coupled to the opening 334 in the stator housing 351. Reducing the pressure in the stator housing 351 pushes the Paschen curve location further to the left. This reduces the risk of igniting the plasma within the stator housing 351. Further, it should be appreciated that the pressure difference at the interface between volume 357 and the inner volume 358 is not extremely high. This allows the dynamic seal 336 to function effectively. That is, the dynamic seal 336 does not need to support the difference between the vacuum pressure and the atmospheric pressure.

[0038] Next, referring to FIG. 4, a block diagram of an exemplary computer system 400 of a processing tool according to one embodiment is shown. In one embodiment, computer system 400 is coupled to the processing tool and controls the processing in the processing tool. Computer system 400 can be connected (e.g., networked) to other machines in a local area network (LAN), intranet, extranet, or the Internet. Computer system 400 can operate as a server machine or a client machine in a client-server network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. Computer system 400 can be a personal computer (PC), tablet PC, set-top box (STB), personal digital assistant (PDA), cellular phone, web appliance, server, network router, switch or bridge, or any machine capable of executing a set (serial or otherwise) of instructions that specify actions to be taken by that machine. Further, although only a single machine is shown for computer system 400, the term "machine" shall also be construed to include any collection of machines (e.g., computers) that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies described herein.

[0039] Computer system 400 may include a computer program product, or software 422, having a non-transitory machine-readable medium storing instructions that may be used to program the computer system 400 (or other electronic device) to perform a process according to an embodiment. The machine-readable medium includes any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computer). For example, the machine-readable (e.g., computer-readable) medium includes machine (e.g., computer) readable storage media (e.g., read-only memory ("ROM"), random access memory ("RAM"), magnetic disk storage media, optical storage media, flash memory devices, etc.), machine (e.g., computer) readable transmission media (electrical, optical, acoustic, or other forms of propagated signals (e.g., infrared signals, digital signals, etc.)), and the like.

[0040] In one embodiment, computer system 400 includes a system processor 402, a main memory 404 (e.g., dynamic random access memory (DRAM) such as read-only memory (ROM), flash memory, synchronous DRAM (SDRAM), etc., or Rambus DRAM (RDRAM)), a static memory 406 (e.g., flash memory, static random access memory (SRAM), etc.), and a secondary memory 418 (e.g., a data storage device) that communicate with each other via a bus 430.

[0041] The system processor 402 represents one or more general-purpose processing devices, such as a micro-system processor, a central processing unit, etc. More specifically, the system processor can be a complex instruction set computing (CISC) micro-system processor, a reduced instruction set computing (RISC) micro-system processor, a very long instruction word (VLIW) micro-system processor, a system processor implementing other instruction sets, or a system processor implementing a combination of instruction sets. The system processor 402 can also be one or more dedicated processing devices, such as an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal system processor (DSP), a network system processor, etc. The system processor 402 is configured to execute processing logic 426 for performing the operations described herein.

[0042] The computer system 400 may further include a system network interface device 408 for communicating with other devices or machines. The computer system 400 may also include a video display unit 410 (e.g., a liquid crystal display (LCD), a light-emitting diode display (LED), or a cathode ray tube (CRT)), an alphanumeric input device 412 (e.g., a keyboard), a cursor control device 414 (e.g., a mouse), and a signal generation device 416 (e.g., a speaker).

[0043] The secondary memory 418 may include a machine-accessible storage medium 432 (or more particularly, a computer-readable storage medium) storing one or more sets of instructions (e.g., software 422) that embody any one or more of the methodologies or functions described herein. The software 422 may also exist, in whole or at least in part, within the main memory 404 and / or within the system processor 402 during execution of the software 422 by the computer system 400, where the main memory 404 and the system processor 402 also form a machine-readable storage medium. The software 422 may further be transmitted or received over the network 420 via the system network interface device 408. In one embodiment, the network interface device 408 may operate using RF coupling, optical coupling, acoustic coupling, or inductive coupling.

[0044] Although the machine-accessible storage medium 432 is shown as a single medium in the exemplary embodiments, the term "machine-readable storage medium" should be interpreted to include a single medium or multiple media (e.g., a centralized or distributed database, and / or associated caches and servers) storing one or more sets of instructions. The term "machine-readable storage medium" should also be interpreted to include any medium that is capable of storing or encoding a set of instructions for machine execution and causing a machine to perform any one or more of the methodologies. The term "machine-readable storage medium" should therefore be interpreted to include, without limitation, solid-state memories as well as optical and magnetic media.

[0045] In the foregoing specification, specific exemplary embodiments have been described. It will be apparent that various modifications may be made thereto without departing from the scope of the following claims. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a limiting sense.

Claims

1. A chamber, a chuck within the chamber, the chuck being configured to rotate, a pedestal holder around the chuck, and a utility column coupled to the chuck and comprising a magnetic coupler for enabling rotation of the utility column and a portion of the chuck, and a rotary electrical feedthrough, a semiconductor processing tool.

2. The magnetic coupler comprises a bushing, the bushing being fixed, a first set of magnets outside the bushing, a second set of magnets inside the bushing, and a tube coupled to the second set of magnets, the semiconductor processing tool according to claim 1.

3. The rotary electrical feedthrough comprises a stator housing, and a rotor, the semiconductor processing tool according to claim 2.

4. An RF return path is provided along the pedestal holder, the bushing, and the stator housing, the semiconductor processing tool according to claim 3.

5. The RF return path is electrically insulated from conductive components other than the pedestal holder, the bushing, and the stator housing, and an outer race of a mechanical bearing inside the bushing is electrically insulated from the RF return path, the semiconductor processing tool according to claim 3.

6. The interior of the tube and the rotary electrical feedthrough are sealed to enable maintaining a chamber vacuum pressure in the tube and the rotary electrical feedthrough, the semiconductor processing tool according to claim 3.

7. A dynamic seal fluidly insulates the rotary electrical feedthrough and the interior of the tube from outside the tube, and the rotary electrical feedthrough and the interior of the tube are configured to be held at a pressure different from the pressure in a wafer cavity and a process cavity in the chamber, the semiconductor processing tool according to claim 3.

8. The semiconductor processing tool is a physical vapor deposition (PVD) tool, the semiconductor processing tool according to claim 1.

9. The rotary electrical feedthrough comprises up to seven electrical inputs, the semiconductor processing tool according to claim 1.

10. The semiconductor processing tool of claim 9, wherein the electrical input is provided to one or more heaters and one or more chuck electrodes. Claim 11 A backside gas line for a substrate on a chuck, the backside gas line being centered on an axis of the utility column, a dynamic seal being provided around the backside gas line at a bottom of the rotary electrical feedthrough, and backside gas thermally coupling the substrate to the chuck. The semiconductor processing tool of claim 1, further comprising the backside gas line. Claim 12 A stator housing, an electrical transmission assembly within the stator housing, a first insulator between the electrical transmission assembly and the stator housing, a rotor electrically coupled to the electrical transmission assembly, a mechanical bearing between the rotor and the stator housing, and a second insulator between the mechanical bearing and the stator housing comprising a rotary electrical feedthrough. Claim 13 The rotary electrical feedthrough of claim 12, wherein the electrical transmission assembly comprises a slip ring, a brush, a liquid metal connection, or a roll ring. Claim 14 An opening configured to be connected to a pump to provide a vacuum pressure inside the stator housing. The rotary electrical feedthrough of claim 12, further comprising the opening. Claim 15 The rotary electrical feedthrough of claim 12, wherein up to seven electrical paths are provided to the electrical transmission assembly. Claim 16 The rotary electrical feedthrough of claim 15, wherein the seven electrical paths are configured to interface with a connector outside the stator housing, and the connector contacts the electrical paths through a sealed port through the stator housing. Claim 17 A magnetic coupler for enabling non-contact rotation, a tube, a bushing around the tube, a housing outside the bushing, a first set of magnets between the tube and the bushing, a second set of magnets between the bushing and the housing, a first bearing between the tube and the bushing, the first bearing being electrically insulating, and a second bearing between the bushing and the housing comprising a magnetic coupler. Claim 18 The magnetic coupler according to claim 17, wherein the first bearing comprises a ceramic material or a metal bearing with a dielectric liner on an outer race of the first bearing for electrical insulation.

19. The magnetic coupler according to claim 17, wherein the magnetic coupler is configured to maintain a vacuum pressure within the bushing and is configured to be exposed to atmospheric pressure outside the bushing.

20. An actuator for rotating the housing, the actuator causing non-contact rotation of the tube when the housing rotates The magnetic coupler according to claim 17, further comprising.

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