WO2020200443A1

WO2020200443A1 - Carrier transport system, vacuum deposition system, and method of transporting a carrier in a vacuum chamber

Info

Publication number: WO2020200443A1
Application number: PCT/EP2019/058418
Authority: WO
Inventors: Oliver Heimel; Ralph Lindenberg
Original assignee: Applied Materials, Inc.
Priority date: 2019-04-03
Filing date: 2019-04-03
Publication date: 2020-10-08
Also published as: CN216435860U

Abstract

A carrier transport system (100) for transporting a carrier (10) in a transport direction (T) is described. The carrier transport system includes a track assembly (150) extending in a vacuum chamber (101) in the transport direction (T). The track assembly includes at least one magnetic levitation unit (136) for levitating a carrier (10) and at least one drive unit (154) for moving the carrier along the track assembly (150). The carrier transport system further includes a transfer device (160) for moving the track assembly (150) in a path switch direction (S) transverse to the transport direction (T), particularly perpendicular to the transport direction (T).

Description

CARRIER TRANSPORT SYSTEM, VACUUM DEPOSITION SYSTEM, AND METHOD OF TRANSPORTING A CARRIER IN A VACUUM CHAMBER

TECHNICAE FIEED

[0001] Embodiments of the present disclosure relate to apparatuses and methods for transportation of carriers, particularly carriers used for carrying large area substrates. More specifically, embodiments of the present disclosure relate to apparatuses and methods for transportation of carriers employable in processing systems for vertical substrate processing, e.g. material deposition on large area substrates for display production. In particular, embodiments of the present disclosure relate to carrier transport systems, vacuum deposition systems, and methods of transporting a carrier in a vacuum chamber.

BACKGROUND

[0002] Techniques for layer deposition on a substrate include, for example, sputter deposition, physical vapor deposition (PVD), chemical vapor deposition (CVD) and thermal evaporation. Coated substrates may be used in several applications and in several technical fields. For instance, coated substrates may be used in the field of display devices. Display devices can be used for the manufacture of television screens, computer monitors, mobile phones, other hand-held devices, and the like for displaying information. Typically, displays are produced by coating a substrate with a stack of layers of different materials.

[0003] In order to deposit a layer on a substrate, an in-line arrangement of processing modules can be used. An in-line processing system includes a plurality of subsequent processing modules, such as deposition modules and optionally further processing modules, e.g., cleaning modules and/or etching modules, wherein processing aspects are subsequently conducted in the processing modules, such that a plurality of substrates can continuously or quasi-continuously be processed in the in line processing system.

[0004] The substrate is typically carried by a carrier, i.e. a carrying device for carrying the substrate. The carrier is typically transported through a vacuum system using a carrier transport system. The carrier transport system may be configured for conveying the carrier carrying the substrate along one or more transport paths. At least two transport paths can be provided next to each other in the vacuum system, e.g. a first transport path T1 for transporting the carrier in a forward direction and a second transport path T2 for transporting the carrier in a return direction opposite to the forward direction.

[0005] The functionality of a display device typically depends on the coating thickness of the material, which has to be within a predetermined range. For obtaining high-resolution display devices, technical challenges with respect to the deposition of materials need to be mastered. In particular, an accurate and smooth transportation of the carriers through the vacuum system is challenging. For instance, particle generation due to wear of moving parts can cause a deterioration in the manufacturing process. Accordingly, there is a demand for the transportation of carriers in vacuum deposition systems with reduced or minimized particle generation. Further challenges are, for example, to provide robust carrier transport systems for high temperature vacuum environments at low costs.

[0006] Accordingly, it would be beneficial to provide improved apparatuses and methods for transporting carriers in a vacuum chamber as well as improved vacuum deposition systems, which overcome at least some problems of the state of the art.

SUMMARY

[0007] In light of the above, carrier transport systems for transporting a carrier in a vacuum chamber, vacuum deposition systems, as well as methods of transporting a carrier in a vacuum chamber according to the independent claims are provided. Further aspects, advantages, and features are apparent from the dependent claims, the description, and the accompanying drawings. [0008] According to an aspect of the present disclosure, a carrier transport system for transporting a carrier is provided. The carrier transport system includes a track assembly extending in a transport direction. The track assembly includes at least one magnetic levitation unit for levitating a carrier and at least one drive unit for moving the carrier along the track assembly. The carrier transport system further includes a transfer device for moving the track assembly in a path switch direction transverse to the transport direction.

[0009] According to an aspect of the present disclosure, a carrier transport system for transporting a carrier is provided. The carrier transport system includes a track assembly extending in the transport direction. The track assembly includes at least one magnetic levitation unit configured to generate a magnetic levitation force for levitating a carrier and at least one drive unit configured to move the carrier along the track assembly in the transport direction. The track assembly is movable together with the carrier in a path switch direction transverse to the transport direction.

[0010] The at least one magnetic levitation unit may include one or more passive levitation magnets, particularly a plurality of permanent magnets for levitating the carrier.

[0011] In some embodiments, the carrier transport system described herein is configured to transport the carrier in a vacuum environment, and the movable track assembly is located inside a vacuum chamber. In other embodiments, the carrier transport system described herein is configured to transport the carrier in an atmospheric environment, and the movable track assembly is arranged outside a vacuum chamber.

[0012] According to an aspect of the present disclosure, a carrier transport system for transporting a carrier in a vacuum chamber is provided. The carrier transport system includes a vacuum chamber and a track assembly extending in the vacuum chamber in the transport direction. The track assembly includes a pressure- tight enclosure configured to maintain a predetermined pressure therein, particularly an atmospheric pressure, at least one magnetic levitation unit for levitating a carrier, and at least one drive unit for moving the carrier along the track assembly. At least one of the at least one magnetic levitation unit and the at least one drive unit is arranged inside the pressure -tight enclosure.

[0013] In an embodiment, a linear motor configured to move the carrier in the transport direction along the track assembly is arranged in the pressure-tight enclosure.

[0014] According to a further aspect of the present disclosure, a vacuum deposition system is provided. The vacuum deposition system includes a vacuum chamber, a track assembly extending in the vacuum chamber in a transport direction, a deposition source, and a transfer device. The track assembly includes at least one magnetic levitation unit for levitating a carrier and at least one drive unit for moving the carrier along the track assembly. The transfer device is configured to move the track assembly in a path switch direction toward or away from the deposition source.

[0015] According to a further aspect of the present disclosure, a method of transporting a carrier in a vacuum chamber is provided. The method includes transporting the carrier along a track assembly in a transport direction while levitating the carrier with at least one magnetic levitation unit of the track assembly. The method further includes transferring the track assembly together with the carrier in a path switch direction transverse to the transport direction.

[0016] Further, the carrier may be moved along the track assembly with at least one drive unit of the track assembly, particularly with a linear motor.

[0017] Embodiments are also directed at apparatuses for carrying out the disclosed methods and include apparatus parts for performing each described method aspect. These method aspects may be performed by way of hardware components, a computer programmed by appropriate software, by any combination of the two or in any other manner. Furthermore, embodiments according to the disclosure are also directed at methods for operating the described apparatus. The methods for operating the described apparatus include method aspects for carrying out every function of the apparatus. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] 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. The accompanying drawings relate to embodiments of the disclosure and are described in the following:

FIG. 1 shows a schematic sectional view of a carrier transport system according to embodiments described herein;

FIG. 2 shows a schematic top view of a carrier transport system according to embodiments described herein;

FIG. 3A shows a schematic sectional view of a vacuum deposition system according to embodiments described herein in a first position;

FIG. 3B shows the vacuum deposition system of FIG. 3 A in a processing position;

FIG. 3C shows the vacuum deposition system of FIG. 3 A in a second position; FIG. 4 shows a lower part of a carrier transport system according to embodiments described herein in a schematic sectional view; and

FIG. 5 is a flow diagram illustrating a method of transporting a carrier in a vacuum chamber according to embodiments described herein.

DETAILED DESCRIPTION OF EMBODIMENTS [0019] Reference will now be made in detail to the various embodiments of the disclosure, one or more examples of which are illustrated in the figures. Within the following description of the drawings, the same reference numbers refer to same components. Only the differences with respect to individual embodiments are described. Each example is provided by way of explanation of the disclosure and is not meant as a limitation of the disclosure. Further, features illustrated or described as part of one embodiment can be used on or in conjunction with other embodiments to yield yet a further embodiment. It is intended that the description includes such modifications and variations.

[0020] A carrier transport system is configured for transporting a carrier in a vacuum environment, particularly in a vacuum chamber or in a vacuum system including a plurality of vacuum chambers arranged next to each other, e.g. in a linear array. The carrier transport system may provide one, two or more transport paths, wherein the carrier can be moved or conveyed along the one or more transport paths in a transport direction. A first transport path T1 may extend next to a second transport path T2, e.g., essentially parallel to the first transport path Tl. The first transport path Tl and/or the second transport path T2 may extend next to each other in a transport direction T which may be an essentially horizontal direction.

[0021] The first transport path Tl and the second transport path T2 may be offset from each other in a path switch direction S. The distance between the first transport path Tl and the second transport path T2 in the path switch direction S may be 10 cm or more, particularly 20 cm or more, and/or 100 cm or less, particularly 50 cm or less.

[0022] The carrier transport system described herein can be a part of a vacuum processing system, particularly a vacuum deposition system configured for depositing a material on a substrate carried by a carrier. The vacuum deposition system may be an in-line processing system, such that a substrate can be continuously or quasi-continuously processed. The carrier transport system may be configured to displace or transfer the carrier from a first position on the first transport path Tl away from the first transport path Tl to at least one of the second transport path T2 and a processing position P in which the substrate can be processed. Specifically, the carrier transport system can laterally displace the carrier from a first position on the first transport path Tl to a second position away from the first transport path in the path switch direction S. The path switch direction S may be transverse to the transport direction T, particularly essentially perpendicular to the transport direction T. When the carrier is moved from one transport path to another transport path in the path switch direction S, said movement is also referred to herein as a“path switch”. [0023] In some embodiments, a levitated carrier is transported along the first transport path T1 in the transport direction T, moved away from the first transport path T1 in the path switch direction S to a processing position P where the substrate is processed, moved in the path switch direction S to the second transport path T2, and is transported along the second transport path T2, e.g. in a direction opposite to the initial direction.

[0024] The carrier transport system may be configured for a contactless transport or an essentially contactless transport of the carrier along the first and/or second transport paths, e.g. using a magnetic levitation force for holding the carrier in a floating state. In other words, the transport system may not use a contacting mechanical force for transporting the carrier. Instead, the transport system may magnetically push or pull the carrier towards a new position. For example, the carrier is magnetically moved by a repulsive and/or an attractive magnetic force along a track assembly extending in the transport direction T.

[0025] In some implementations, there is no mechanical contact between the track assembly and the carrier at all during the carrier transport. In other embodiments, there may be a lateral mechanical contact between the carrier and the track assembly during the transport which may serve for stabilizing the carrier in a lateral direction and/or for preventing a carrier evasion from the track assembly, yet, at least a major part of the weight of the carrier is held by magnetic forces, such that the carrier moves while being in a floating state.

[0026] The carrier transport system may include a magnetic levitation system in some embodiments. The magnetic levitation system may be configured for holding the carrier in a floating state during transport in which a major part of the carrier weight or the whole carrier weight is held by magnetic forces.

[0027] FIG. 1 is a schematic sectional view of a carrier transport system 100 according to embodiments herein. The carrier transport system 100 is configured for transporting a carrier 10 which may carry a substrate 11 in a transport direction T in a vacuum chamber 101. The transport direction T is perpendicular to the paper plane of FIG. 1. The carrier 10 and/or the substrate 11 that is carried by the carrier 10 may have an essentially vertical orientation during the transport (e.g., a vertical orientation +/- 10°).

[0028] The carrier transport system 100 includes a track assembly 150 which extends in the transport direction T in the vacuum chamber 101. The carrier 10 can be moved contactlessly or essentially contactlessly along the track assembly 150 in the vacuum chamber 101.

[0029] According to embodiments described herein, the track assembly 150 includes at least one magnetic levitation unit 156 for levitating the carrier 10 and at least one drive unit 154 for moving the carrier along the track assembly 150 in the transport direction. The at least one magnetic levitation unit 156 may include one or more levitation magnets configured to generate a magnetic levitation force for levitating the carrier, i.e. for magnetically holding the weight or a major part of the weight of the carrier. For example, the at least one magnetic levitation unit 156 may be configured to magnetically hold the carrier above a bottom track 151 or bottom rail of the track assembly 150, as is schematically depicted in FIG. 1.

[0030] The at least one drive unit 154 may be configured to move the carrier 10 along the track assembly 150 in the transport direction. In some embodiments, the at least one drive unit 154 may be configured to move the carrier 10 via magnetic forces. In particular, the at least one drive unit 154 may include at least one linear motor.

[0031] The carrier transport system 100 further includes a transfer device 160 for moving the track assembly 150 in the path switch direction S transverse to the transport direction T. In particular, the track assembly 150 may be movably mounted in the vacuum chamber 101, such that the track assembly 150 can be moved with the transfer device 160 in the path switch direction S. Specifically, a laterally displaceable bottom rail may be provided. The“lateral” direction as used herein may relate to the path switch direction S. In some embodiments, the transfer device 160 is configured to move the track assembly 150 in the path switch direction S together with the carrier 10 which may be held above the bottom track 151 of the track assembly 150 during the path switch movement. [0032] The track assembly 150 can be moved from a first position on the first transport path T1 to at least one of a second position on the second transport path T2 and the processing position P. The transfer device 160 may be configured to move the track assembly without a carrier and/or together with a carrier levitated thereon. For example, the track assembly 150 can be moved together with a carrier away from the first transport path Tl, whereupon the carrier can leave the track assembly 150 in the transport direction T, and the track assembly can be moved back to the first transport path Tl without a carrier. Another carrier may be moved onto the track assembly provided at the first position.

[0033] According to embodiments described herein, the track assembly 150 is movable by the transfer device 160 in the path switch direction. Accordingly, a carrier can be moved along the track assembly 150 in the transport direction T to a path switch position on the track assembly and, thereafter, moved in the path switch direction S together with the track assembly 150 without a hand-over of the carrier to an additional path switch device. Rather, simply by moving the track assembly 150 in the path switch direction S, the carrier can be moved in the path switch direction S as well. Specifically, no additional handling device for conducting a carrier track switch is needed. By moving the carrier together with the track assembly in the path switch direction, the tact rate can be reduced as compared to a situation in which a further handover of the carrier to a path switch device is needed. Further, due to the at least one magnetic levitation unit which can continuously levitate the carrier during the path switch movement, the generation of particles in the vacuum chamber can be reduced. Yet further, the complexity of the carrier design and the risk of carrier vibrations and/or carrier shock during a path switch can be reduced.

[0034] According to embodiments, which can be combined with other embodiments described herein, the transfer device 160 is configured to move the track assembly 150 between the first position on the first transport path Tl depicted in FIG. 1, a second position on the second transport path T2 and/or a processing position P. The processing position P may be closer to a deposition source 105 as compared to the first position and/or the second position. [0035] In some embodiments, the at least one drive unit 154 may comprise a linear motor configured to apply a magnetic force on the carrier for moving the carrier along the track assembly in the transport direction T. The at least one drive unit 154 may include a plurality of linear motors provided at the track assembly, e.g. at predetermined intervals along the transport direction.

[0036] In some implementations, the at least one drive unit may include a synchronous linear motor. In other embodiments, the at least one drive unit may include an asynchronous linear motor. Providing a drive unit including an asynchronous linear motor may be beneficial since an asynchronous linear motor can magnetically interact with a counter-unit 15 provided at the carrier, the counter-unit 15 being, for example, configured as a conductive trace at the carrier. For example, the counter-unit 15 may include a metal plate (e.g., an aluminum plate) provided at a lateral face of the carrier and/or extending in the transport direction T.

[0037] The at least one drive unit may include a linear motor including a plurality of coil units configured to generate a magnetic field for inducing currents in a counter-unit 15 provided at the carrier, e.g. provided at a lateral face of the carrier directed toward the at least one drive unit during transport.

[0038] In some embodiments, which may be combined with other embodiments described herein, the at least one drive unit 154 may be a linear motor provided laterally with respect to a carrier transportation space, such that the linear motor can magnetically interact with the counter-unit 15 provided at the lateral face of the carrier. In some embodiments, the at least one drive unit 154 is arranged to interact with a lower part of the carrier for moving the carrier in the transport direction.

[0039] In some embodiments, which may be combined with other embodiments described herein, the at least one magnetic levitation unit 156 includes a passive magnet unit, particularly a permanent magnet, which is provided at the track assembly 150. The permanent magnet unit is configured to generate a levitation force for levitating the carrier. The permanent magnet may be configured to magnetically interact with another permanent magnet provided at the carrier, such that the carrier can be held in a floating state with respect to the track assembly 150. For example, a vertical displacement of the carrier 10 from an equilibrium position may lead to an increasing restoring force between the permanent magnet provided at the track assembly and the other permanent magnet provided at the carrier, such that the carrier maintains the equilibrium position and does not sag/sink below or rise above a predetermined vertical level.

[0040] Specifically, a passive magnetic levitation system including permanent magnets only may be provided for levitating the carrier with respect to the track assembly 150. The at least one magnetic levitation unit 156 may include a first plurality of permanent magnets provided at preset intervals at the track assembly 150, and a second plurality of permanent magnets configured to magnetically interact with the first plurality of permanent magnets may be provided at the carrier. The at least one magnetic levitation unit 156 may be configured to hold the weight of the carrier, e.g. above a bottom track or lower rail of the track assembly 150.

[0041] In other embodiments, the at least one magnetic levitation unit 156 may include one or more actively controlled magnet units, e.g. a plurality of actively controlled magnetic bearings which hold the carrier at a predetermined distance from the track assembly 150 via a feedback loop. For example, a distance between the carrier and the track assembly may be measured with one or more distance sensors, and one or more actively controlled magnet units may be controlled as a function of the measured distance.

[0042] Providing the at least one magnetic levitation unit as a purely passive magnet unit may be beneficial, since costs can be reduced - no active control being necessary -, and since problems with heat generation and power supply of active magnetic units in a vacuum chamber can be reduced. Further, the risk of a failure of the magnetic levitation system can be reduced, since permanent magnets are typically particularly fail-safe.

[0043] According to embodiments, which can be combined with other embodiments described herein, the track assembly 150 includes a bottom track 151 (also referred to herein as a“drive bar” or“lower rail”) which extends along the transport direction T at least partially below the carrier transportation space. The bottom track 151 may include a recess or a channel extending in the transport direction T into which a lower carrier portion may protrude during the transport, as is schematically depicted in FIG. 1. Specifically, a lower portion of the carrier which may carry one or more magnetic counter-units may protrude into a recess of the bottom track 151 extending in the transport direction T. The at least one magnetic levitation unit 156 of the track assembly 150 may be arranged laterally on both sides of the recess, such that the at least one magnetic levitation unit 156 can magnetically interact with the one or more magnetic counter-units of the carrier and keep the carrier at a predetermined vertical and/or lateral position with respect to the recess.

[0044] In some embodiments, a side stabilization unit configured to stabilize the carrier in the path switch direction S may further be provided at the track assembly. The stabilization unit may ensure a correct carrier position in the path switch direction (lateral direction) during the carrier transport along the transport direction. The side stabilization unit may be a magnetic side stabilization unit or a side stabilization unit providing a mechanical contact with the carrier.

[0045] The transfer device 160 may include a movable arm connected to the track assembly 150 and configured to shift the track assembly 150 in the path switch direction. A motor may be provided for moving the movable arm in the path switch direction. In some embodiments, the motor is arranged outside the vacuum chamber.

[0046] FIG. 2 is a schematic top view of a carrier transport system 100 according to embodiments described herein. The carrier transport system of FIG. 2 is similar to the carrier transport system of FIG. 1, such that reference can be made to the above explanations, which are not repeated here.

[0047] The carrier transport system 100 includes a track assembly 150 extending in the transport direction T in a vacuum chamber 101. The vacuum chamber 101 may be a processing vacuum chamber which houses a deposition source 105. Two or more carrier transportation paths (first transport path T1 and second transport path T2 in FIG. 2) may extend at least partially through the vacuum chamber 101 in the transport direction T. As is indicated by the two arrows in FIG. 2, the track assembly 150 is movably mounted in the vacuum chamber 101. Specifically, the track assembly 150 can be transferred from the first position on the first transport path T1 depicted in FIG. 2 to a second position away from the first transport path Tl, e.g. on the second transport path T2.

[0048] The track assembly 150 includes at least one magnetic levitation unit for levitating a carrier (not shown in FIG. 2). The track assembly 150 is movable in the path switch direction S with or without a carrier 10 levitated on the track assembly 150 by the at least one magnetic levitation unit 156. The track assembly 150 further includes at least one drive unit 154 for moving the carrier along the track assembly. The at least one drive unit 154 may include a linear motor including coils provided along the transport direction T at predetermined intervals.

[0049] Both the at least one magnetic levitation unit 156 and the at least one drive unit 154 are movable together with the track assembly 150 in the path switch direction S. Accordingly, the at least one magnetic levitation unit 156 of the track assembly is suitable for levitating the carrier both at the first position on the first transport path Tl and at the second position on the second transport path T2. Further, the at least one drive unit 154 is suitable for moving a carrier both along the first transport path Tl and along the second transport path T2.

[0050] In some embodiments, at least one second vacuum chamber 102 may be arranged next to the vacuum chamber 101, e.g. a high vacuum chamber, a low vacuum chamber, a loading chamber, and/or a load lock chamber. Further track assemblies 111 may be provided next to the track assembly 150 in the transport direction T, such that the carrier can be transported from the track assembly 150 to one or more of the further track assemblies 111. The further track assemblies 111 may not be movably mounted, i.e. may be stationary, e.g. fixed to the at least one second vacuum chamber 102. Accordingly, each further track assembly may be located on one of the transport paths. The further track assemblies 111 may include further magnetic levitation units for levitating the carrier and/or further drive units for moving the carrier along the further track assemblies.

[0051] FIG. 3 A is a schematic sectional view of a vacuum deposition system 200 according to embodiments described herein. The vacuum deposition system 200 may include a carrier transport system 100 as described above, such that reference can be made to the above explanations, which are not repeated here.

[0052] The vacuum deposition system 200 includes a vacuum chamber 101, a track assembly 150 extending in the vacuum chamber 101 in the transport direction T, and a deposition source 105 arranged in the vacuum chamber 101. The track assembly 150 is movable in the path switch direction S and includes at least one magnetic levitation unit 156 for levitating a carrier and at least one drive unit 154 for moving the carrier along the track assembly 150. The track assembly 150 can be moved in the path switch direction S via a transfer device 160 configured to move the track assembly 150 toward the deposition source 105 and/or away from the deposition source 105.

[0053] The deposition source 105 may be a sputter deposition source, e.g. a sputter deposition source including a plurality of targets which may optionally be rotatable. Alternatively, the deposition source 105 may be at least one of a CVD source, an evaporation source, and a PVD source.

[0054] In some embodiments, which can be combined with other embodiments described herein, the track assembly 150 includes a bottom track 151 and a top track 152 arranged above the bottom track 151 in a vertical direction. A carrier transportation space in which the carrier 10 is arranged during the transport extends between the bottom track 151 and the top track 152.

[0055] For example, a lower portion of the carrier 10 may extend downward into a recess or guiding channel of the bottom track 151 during the transport, and/or an upper portion of the carrier 10 may extend upward into a recess or guiding channel of the top track 152 during the transport, as is schematically depicted in FIG. 3 A. [0056] In some embodiments, the at least one drive unit 154 is arranged at the bottom track 151.

[0057] In some embodiments, the at least one magnetic levitation unit 156, particularly a passive magnet unit, more particularly a permanent levitation magnet is arranged at the bottom track 151. [0058] In some embodiments, a side stabilization unit 158 for stabilizing the carrier 10 in the path switch direction S is provided at the top track 152. For example, the side stabilization unit 158 is a magnetic side stabilization unit configured to hold the upper portion of the carrier at a predetermined lateral position. A tilting of the upper portion of the carrier can be reduced or prevented by the side stabilization unit 158. The side stabilization unit 158 may include a plurality of permanent magnets configured to apply a repulsive magnetic force to an upper portion of the carrier, such that the upper portion of the carrier is held at an equilibrium position.

[0059] In some embodiments, which can be combined with other embodiments described herein, the transfer device 160 includes a lower transfer device for moving the bottom track 151 in the path switch direction and/or an upper transfer device for moving the top track 152 in the path switch direction. The bottom track 151 and the top track 152 can be transferred in the path switch direction S essentially synchronously, such that the upper portion of the carrier can be held essentially above the lower portion of the carrier while the lower portion of the carrier is moved in the path switch direction. In some embodiments, the lower transfer device and the upper transfer device include a respective movable arm and a respective motor for moving the movable arm. Alternatively, one motor is provided for moving both the bottom track 151 and the top track 152 in the path switch direction.

[0060] A carrier 10 carrying a substrate 11 can be moved in a carrier transportation space between the bottom track 151 (or lower rail) and the top track 152 (or upper rail) of the track assembly 150 to a first position on the first transport path T1 that is depicted in FIG. 3 A. The movement of the carrier 10 along the track assembly 150 can be completely or essentially contactless, i.e. the carrier may be held in a floating state by a magnetic levitation system.

[0061] Thereupon, as is schematically depicted in FIG. 3B, the transfer device 160 can move the track assembly 150 including the bottom track 151 and the top track 152 in the path switch direction S to a processing position P away from the first transport path Tl. During said path switch movement, the carrier 10 can be levitated by the at least one magnetic levitation unit 156 of the track assembly 150, such that the carrier moves together with the track assembly 150 in the path switch direction S.

[0062] A material can be deposited on the substrate 11 that is carried by the carrier 10 in the processing position P with the deposition source 105, as is schematically indicated by three arrows in FIG. 3B.

[0063] Thereupon, as is schematically depicted in FIG. 3C, the transfer device 160 can move the track assembly 150 including the bottom track 151 and the top track 152 in the path switch direction S to a second position on the second transport path T2. During said path switch movement, the carrier 10 can be levitated by the at least one magnetic levitation unit 156 of the track assembly 150, such that the carrier moves together with the track assembly 150 in the path switch direction S toward the second transport path T2.

[0064] Thereupon, the carrier 10 can leave the track assembly 150, e.g. toward another vacuum chamber, by moving the carrier in the transport direction with the at least one drive unit 154 of the track assembly 150. The movement of the carrier along the track assembly 150 can be a completely or essentially contactless movement, i.e. during the movement a major part of the weight of the carrier is held via a magnetic levitation force generated by the at least one magnetic levitation unit 156. [0065] A quick and reliable path switch of the carrier without carrier hand-over and with a reduced risk of particle generation can be provided.

[0066] FIG. 4 is an enlarged view of a lower part of a carrier transport system 300 according to embodiments described herein in a schematic sectional view. The carrier transport system 300 may essentially correspond to the carrier transport system 100 of FIG. 1 and FIG. 2, such that reference can be made to the above explanations, which are not repeated here.

[0067] The carrier transport system includes a track assembly 150 which may include a bottom track 151 and optionally a top track 152. Only the bottom track 151 is depicted in FIG. 4. The track assembly 150 includes at least one drive unit 154 configured for moving the carrier 10 along the track assembly 150 in the transport direction T and at least one magnetic levitation unit 156 configured to generate a magnetic levitation force for levitating the carrier. The at least one drive unit 154 and the at least one magnetic levitation unit 156 may be arranged at the bottom track 151.

[0068] In some embodiments, which may be combined with other embodiments described herein, the track assembly 150 includes a pressure-tight enclosure 170, configured to maintain a predetermined pressure therein. Specifically, the pressure- tight enclosure may be an atmospheric box configured to maintain atmospheric pressure therein. Since the pressure -tight enclosure 170 is part of the track assembly 150, the transfer device 160 is configured to move the pressure-tight enclosure 170 together with the track assembly 150 in the path switch direction S. Providing a pressure-tight enclosure 170 at the track assembly 150 may be beneficial, because non-vacuum compatible components can be arranged inside the pressure-tight enclosure 170.

[0069] In some embodiments, at least one of the at least one drive unit 154 and the at least one magnetic levitation unit 156 is arranged inside the pressure-tight enclosure 170. In the embodiment depicted in FIG. 4, the at least one drive unit 154 is arranged inside the pressure-tight enclosure 170. Accordingly, the at least one drive unit 154 may include non- vacuum compatible components.

[0070] According to a separate aspect described herein, which may be made subject matter of an independent claim, a carrier transport system 300 with a pressure-tight enclosure 170 is described, particularly with an atmospheric box configured to maintain atmospheric pressure therein. The carrier transport system 300 may have some or all features of any of the carrier transport systems described herein.

[0071] The carrier transport system 300 includes a vacuum chamber 101, and a track assembly 150 extending in a transport direction T in the vacuum chamber 101. The track assembly 150 includes a pressure-tight enclosure 170 configured to maintain a predetermined pressure therein. The track assembly 150 further includes at least one magnetic levitation unit 156 for levitating a carrier 10 and at least one drive unit 154 for moving the carrier along the track assembly 150. At least one of the at least one magnetic levitation unit 156 and the at least one drive unit 154 is arranged inside the pressure-tight enclosure 170. In the embodiment depicted in FIG. 4, the at least one drive unit 154, particularly a linear motor, is arranged inside the pressure-tight enclosure 170. The pressure-tight enclosure 170 may be configured to maintain atmospheric pressure therein.

[0072] Accordingly, since the at least one drive unit 154 is arranged in an atmospheric environment, particularly in an atmospheric box provided inside the vacuum chamber 101, the at least one drive unit 154 does not need to be vacuum- compatible. This increases the flexibility and reduces costs. Further, the at least one drive unit 154 being arranged inside the pressure-tight enclosure 170 can be moved together with the track assembly 150 in the path switch direction S during operation. Accordingly, the at least one drive unit 154 can be positioned and adjusted as appropriate by moving the track assembly 150 to a predetermined position. Yet further, the supply of the at least one drive unit, e.g. with cooling fluid, signals and/or power, is facilitated, since supply lines 165 may extend from outside the vacuum chamber into the pressure -tight enclosure, i.e. into an atmospheric environment, such that the number of vacuum-feedthroughs can be reduced. Particularly, the supply lines may be provided in an atmospheric environment along the whole extension of the supply lines, as there may be no need for the supply lines to enter a vacuum environment of the vacuum chamber.

[0073] Yet further, the pressure-tight enclosure 170 having the at least one drive unit 154 provided therein can be pre-configured and commissioned as a sub- assembly that can be readily and quickly installed in the vacuum chamber, and the risk of a contamination of the vacuum chamber is reduced.

[0074] In some embodiments, which can be combined with other embodiments described herein, the transfer device 160 includes at least one movable arm 161 that is connected to the track assembly 150 and at least one motor 162 for moving the movable arm 161 together with the track assembly 150 connected thereto in the path switch direction S. [0075] The movable arm 161 may extend through a wall of the vacuum chamber 101 to the outside of the vacuum chamber 101, and the motor 162 may be arranged outside the vacuum chamber 101. Maintenance and service of the transfer device 160, particularly of the motor 162, can be facilitated, and a conventional motor can be used which is not vacuum-compatible.

[0076] The movable arm 161 may extend through a sidewall of the vacuum chamber into the vacuum chamber where a distal part of the movable arm 161 is connected to the track assembly 150. The movable arm 161 can be shifted into the vacuum chamber via the motor 162, the motor being coupled to a proximal part of the movable arm 161 protruding out of the vacuum chamber. For example, the movable arm 161 may be provided with a slide 166 at a proximal part thereof that engages with a track 167, the motor 162 being configured to move the slide 166 along the track 167. Other driving mechanisms are possible.

[0077] In some implementations, the movable arm 161 is connected to the wall of the vacuum chamber 101 via a flexible bellow 163. This allows a movement of the movable arm 161 relative to the wall through which the movable arm 161 extends while maintaining a pressure difference between two opposing sides of the flexible bellow 163. A vacuum- feedthrough allowing a relative movement between the movable arm 161 and the vacuum chamber 101 is provided. [0078] In some embodiments, which can be combined with other embodiments described herein, the movable arm 161 provides a supply passage for supply lines 165 for supplying the track assembly 150, particularly for supplying at least one of the at least one magnetic levitation unit 156 and the at least one drive unit 154. In some implementations, at least one of a cable and a cooling line extend at least partially through the movable arm 161. The movable arm may be hollow. For example, the movable arm may be configured as a hollow tube element providing a supply passage. Accordingly, the track assembly 150 can be supplied with power and/or cooling fluid in an arbitrary position during the path switch movement. Further, the number of vacuum feed-throughs can be reduced and costs can be saved. [0079] The present description focuses on carrier transport systems for transporting a carrier inside a vacuum chamber, e.g. inside a vacuum processing chamber, a vacuum deposition chamber and/or a vacuum transport chamber. However, it is to be noted that any of the carrier transport systems described herein can also be configured for transporting a carrier in an atmospheric environment, and the movable track assembly may be arranged outside a vacuum chamber.

[0080] For example, the carrier transport assembly may include a track assembly extending in the transport direction and a transfer device for moving the track assembly in the path switch direction transverse to the transport direction. The track assembly may be arranged in an atmospheric environment, e.g. adjacent to a vacuum deposition system, in particular next to a closable opening of a load lock vacuum chamber of a vacuum deposition system. The load lock vacuum chamber may be configured as an airlock chamber for sluicing a carrier into a high-vacuum chamber. Accordingly, the carrier transport system described herein may be used for conducting a path switch of a carrier outside a vacuum deposition system, e.g. before the carrier re-enters the vacuum deposition system through the load lock chamber.

[0081] In some embodiments, a vacuum deposition system with a plurality of vacuum chambers includes at least one carrier transport assembly as described herein arranged inside a vacuum chamber of the vacuum deposition system, e.g. inside a vacuum deposition chamber, and at least one second carrier transport assembly as described herein arranged outside the vacuum chambers of the vacuum deposition system. Accordingly, carriers can conduct path switches inside the vacuum deposition system, e.g. in a first path switch direction, and carriers can conduct path switches outside the vacuum deposition system, e.g. in a second path switch direction opposite the first path switch direction. Thus, carriers can be transported along a looped path comprising two parallel carrier transport paths and two carrier transport assemblies for conducting path switches between the two carrier transport paths, the looped path being partially in a vacuum environment and partially in an atmospheric environment.

[0082] FIG. 5 is a flow diagram illustrating a method of transporting a carrier 10 in a vacuum chamber 101 according to embodiments described herein. [0083] In box 510, a carrier 10 is transported along a track assembly 150 in a transport direction T while levitating the carrier with at least one magnetic levitation unit 156 of the track assembly 150.

[0084] In box 520, the track assembly 150 is transferred together with the carrier that is levitated by the track assembly in a path switch direction S transverse to the transport direction. Specifically, the track assembly 150 including the at least one magnetic levitation unit 156 and including at least one drive unit 154 are moved together with the carrier in the path switch direction, e.g. from a first transport path T1 to at least one of a second transport path T2 and a processing position P. In some embodiments, the track assembly 150 is transferred together with the carrier from a first position on a first transport path T1 to at least one of a second position on a second transport path T2 and a processing position P.

[0085] In optional box 530, a material is deposited on a substrate carried by the carrier, the carrier being arranged at the processing position P close to a deposition source.

[0086] Embodiments described herein can be used for transporting carriers carrying at least one of large-area substrates, glass substrates, wafers, semiconductor substrates, masks, shields, and other objects. The carriers can carry one single object, e.g., a large-area substrate with a size of 1 m² or more, particularly 5 m² or 10 m² or more, or a plurality of objects having a smaller size, e.g. a plurality of semiconductor wafers. The carrier may include a holding device configured to hold the object at the carrier, e.g. a magnetic chuck, an electrostatic chuck, or a mechanical chucking device.

[0087] The carrier may have an essentially vertical orientation during transport (e.g., vertical +/- 10°), or the carrier may have an essentially horizontal orientation during transport (e.g., horizontal +/- 10°). Specifically, the vacuum deposition system may be configured for vertical substrate processing or for horizontal substrate processing. [0088] While the foregoing is directed to embodiments, other and further embodiments may be devised without departing from the basic scope, and the scope is determined by the claims that follow.

Claims

1. A carrier transport system (100), comprising a track assembly (150) extending in a transport direction (T), the track assembly comprising: at least one magnetic levitation unit (156) for levitating a carrier (10); and at least one drive unit (154) for moving the carrier along the track assembly

(150), the carrier transport system further comprising a transfer device (160) for moving the track assembly (150) in a path switch direction (S) transverse to the transport direction (T). 2. The carrier transport system of claim 1, wherein the transfer device (160) is configured for moving the track assembly between a first position on a first transport path (Tl), a second position on a second transport path (T2), and/or a processing position (P).

3. The carrier transport system of claim 1 or 2, wherein the at least one drive unit (154) comprises a linear motor.

4. The carrier transport system of any of claims 1 to 3, wherein the at least one magnetic levitation unit (156) comprises a passive magnet unit, particularly a permanent magnet unit configured to hold the carrier in a floating state.

5. The carrier transport system of any of claims 1 to 4, wherein the track assembly (150) comprises a bottom track (151) and a top track (152), the at least one magnetic levitation unit (156) and/or the at least one drive unit (154) being provided at the bottom track.

6. The carrier transport system of claim 5, wherein a side stabilization unit (158) for stabilizing the carrier in the path switch direction (S), particularly a magnetic side stabilization unit, is provided at the top track (152).

7. The carrier transport system of claim 5 or 6, wherein the transfer device (160) comprises a lower transfer device for moving the bottom track (151) in the path switch direction (S) and an upper transfer device for moving the top track (152) in the path switch direction (S) synchronously with the bottom track (151). 8. The carrier transport system of any of claims 1 to 7, wherein the track assembly (150) comprises a pressure-tight enclosure (170) configured to maintain a predetermined pressure therein, particularly an atmospheric pressure, wherein the at least one drive unit (154) is arranged inside the pressure-tight enclosure.

9. The carrier transport system of any of claims 1 to 8, wherein the transfer device (160) comprises : at least one movable arm (161) extending through a wall of a vacuum chamber (101) and connected to the track assembly (150); and at least one motor (162) arranged outside the vacuum chamber (101) for moving the movable arm (161) in the path switch direction (S). 10. The carrier transport system of claim 9, wherein the movable arm is connected to the wall of the vacuum chamber (101) via a flexible bellow (163).

11. The carrier transport system of claim 9 or 10, wherein the movable arm provides a supply passage, particularly wherein at least one of a cable and a line for cooling fluid extends at least partially through the movable arm. 12. A carrier transport system (100), comprising a track assembly (150) extending in a transport direction (T), the track assembly comprising: at least one magnetic levitation unit (156) configured to generate a magnetic levitation force for levitating a carrier (10); and at least one drive unit (154) configured to move the carrier (10) along the track assembly (150) in the transport direction (T), wherein the track assembly (150) is movable together with the carrier in a path switch direction (S) transverse to the transport direction (T).

13. A vacuum deposition system, comprising : a vacuum chamber (101); a track assembly (150) extending in the vacuum chamber in a transport direction (T), comprising: at least one magnetic levitation unit (156) for levitating a carrier (10); and at least one drive unit (154) for moving the carrier along the track assembly (150), a deposition source (105); and a transfer device (160) for moving the track assembly (150) in a path switch direction (S) toward or away from the deposition source.

14. A method of transporting a carrier (10) in a vacuum chamber (101), comprising: transporting the carrier (10) along a track assembly (150) in a transport direction (T) while levitating the carrier with at least one magnetic levitation unit (156) of the track assembly (150); and transferring the track assembly (150) together with the carrier in a path switch direction (S) transverse to the transport direction (T). 15. The method of claim 14, comprising: transferring the track assembly (150) together with the carrier from a first position on a first transport path (Tl) to at least one of a second position on a second transport path (T2) and a processing position (P); and depositing a material on a substrate carried by the carrier.

16. A carrier transport system (100), comprising a vacuum chamber; and a track assembly (150) extending in the vacuum chamber (101) in a transport direction (T), the track assembly comprising: a pressure-tight enclosure (170) configured to maintain a predetermined pressure therein, particularly an atmospheric pressure; at least one magnetic levitation unit (156) for levitating a carrier (10); and at least one drive unit (154) for moving the carrier along the track assembly (150), wherein at least one of the at least one magnetic levitation unit (156) and the at least one drive unit (154) is arranged inside the pressure-tight enclosure (170).