PROCESSING SYSTEM

FIELD OF INVENTION

[0001] Embodiments of the present disclosure relate to apparatuses and methods for transporting a device, particularly carriers for carrying substrates or masks during processing. More specifically, the present disclosure relates to apparatuses and methods for transporting devices in a vacuum processing system employing magnetic levitation.

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 can 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 stack, an in-line arrangement of processing modules can be used. An in-line processing system includes a plurality of 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 may be supported by a carrier, i.e. a carrying device for carrying the substrate in the vacuum system. The carrier carrying the substrate is typically transported through the vacuum system using a transport system. The transport system may be a magnetic levitation system, such that the carrier can be transported contactlessly or essentially contactlessly.

[0005] While magnetic levitation systems have many advantages, enhancing and accelerating the transport of devices in the vacuum system is challenging. For instance, driving efficiency in a magnetic levitation system used in vacuum processing systems is dependent on a variety of factors that need to be considered.

[0006] Accordingly, there is a demand for providing improved systems and methods for transporting devices such as carriers, particularly for vacuum processing systems, which overcome at least some of the problems of the state of the art.

SUMMARY

[0007] In light of the above, a drive unit for moving a device in a vacuum processing system is provided. The drive unit includes one or more electromagnets having one or more coils, and a housing, the one or more electromagnets being arranged within the housing. The housing includes a rib-structure that covers the one or more electromagnets, the rib-structure having one or more structures extending in a common direction towards the one or more electromagnets.

[0008] According to an aspect of the present disclosure, a drive unit for moving a device in a vacuum processing system is provided. The drive unit includes one or more electromagnets having one or more cores, and a housing, the one or more electromagnets being arranged within the housing. The housing comprises a rib-structure that covers the drive unit, the rib-structure having a one or more structures extending in a common direction away from the one or more electromagnets.

[0009] According to a further aspect of the present disclosure, a transportation apparatus, particularly a magnetic transportation apparatus, is provided. The transportation apparatus includes a drive unit according to embodiments described herein, and a device comprising one or more first magnetic counterparts for interacting with the one or more electromagnets of the drive unit.

[0010] According to a further aspect of the present disclosure, a vacuum processing apparatus is provided. The vacuum processing apparatus includes one or more vacuum chambers, and a transportation apparatus according to embodiments described herein, the transportation apparatus being provided inside the one or more vacuum chambers.

[0011] According to a further aspect of the present disclosure, a method for moving a device is provided. The method includes providing a drive unit having a housing and a rib-structure, the rib- structure comprising one or more structures extending in a common direction and covering one or more electromagnets arranged in the housing; and moving the device by using the drive unit.

[0012] 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 present disclosure are also directed at methods for operating the described apparatus. It includes method aspects for carrying out every function of the apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS [0013] 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 side view of a drive unit and a device according to embodiments described herein;

Fig. 2 shows a side view of a drive unit according to embodiments described herein;

Fig. 3A shows a front view of a drive unit according to embodiments described herein; Fig. 3B shows a bottom view of a rib-structure according to embodiments described herein; Fig. 4 shows a vacuum processing apparatus according to embodiments described herein; and

Fig. 5 shows a flow diagram of a method according to embodiments described herein.

DETAILED DESCRIPTION OF EMBODIMENTS

[0014] 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. Generally, 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.

[0015] In vacuum processing systems, transport of devices is an essential procedure to ensure continuous processing of elements and high yields. For example, the devices can be carriers that support a substrate to be processed in the vacuum processing system.

[0016] To allow for a smooth transport, levitation transport apparatuses can be used for transporting devices within a vacuum processing system. For example, magnetic levitation systems for transporting devices through the system can be used. These systems can include, among other features, a drive unit e.g. a linear motor, to provide a movement of the devices in a substantial contactless manner.

[0017] The drive units normally include several actuators or electromagnets providing a force to several magnetic counterparts being arranged at the device to be transported such that the device can be moved in a transport direction along the drive unit. However, providing the drive unit in a vacuum environment is challenging, since many mechanical and electrical components of the electromagnets are not vacuum capable. For example, the provision of electromagnets in a vacuum environment may lead to large outgassing rates and contamination of the processing system.

[0018] Furthermore, the distance between the device to be transported and the drive unit can influence transportation of the device. In particular, the greater the distance, the worse the transfer of forces from the drive unit towards the device. This distance is however also dependent on the electromagnets provided in the drive unit, especially on a thickness of a shield for separating the electromagnets from the surroundings of the drive unit e.g. from a vacuum environment. For example, conventional membrane shields of the drive unit often include a relatively high thickness to provide mechanical stability and to withstand pressure differences occurring between the drive unit and the vacuum environment in vacuum processing systems. [0019] In light of the above, it is beneficial to provide a drive unit that is suitable for the use in a vacuum environment and that provides for improved transportation.

[0020] According to embodiments described herein, a drive unit for moving a device in a vacuum processing system is provided. The drive unit includes one or more electromagnets having one or more coils and a housing. The one or more electromagnets are arranged within the housing. The housing further includes a rib- structure that covers the one or more electromagnets. The rib- structure further has one or more structures extending in a common direction towards the one or more electromagnets.

[0021] According to further embodiments described herein, a drive unit for moving a device in a vacuum processing system is provided. The drive unit includes one or more electromagnets having one or more cores and a housing. The one or more electromagnets are arranged within the housing. The housing further includes a rib-structure that covers the one or more electromagnets. The rib- structure further has one or more structures extending in a common direction away from the one or more electromagnets.

[0022] It is to be understood that the embodiments described herein can provide for alternative solutions to a substantially similar problem, in particular with respect to the independent claims.

[0023] With exemplary reference to Fig. 1, a drive unit 120 and a device 110 is provided according to embodiments herein. The drive unit may be configured to provide a movement to the device 110 in a transport direction T. The drive unit 120 includes one or more electromagnets 124. The device may include one or more second magnetic counterparts 112. The one or more second magnetic counterparts 112 may magnetically interact with the one or more electromagnets of the drive unit such that a movement is provided to the device 110. Between the device 110 and the drive unit 120, i.e. the one or more electromagnets 124, a gap G may be provided. Advantageously, by providing a drive unit according to embodiments described herein, a width of the gap G may be provided as narrow as possible.

[0024] The electromagnets include one or more coils 126. The drive unit 120 includes a housing 122 in which the one or more electromagnets are arranged. The housing 122 further comprises a rib-structure 130, the rib- structure having one or more structures 132. The one or more structures extend in a common direction towards the one or more electromagnets, e.g. in a common direction towards the one or more coils 126.

[0025] According to embodiments, a plurality of the one or more electromagnets 124 may be provided in a repetitive manner next to each other. The plurality of the one or more electromagnets 124 may be arranged sequentially in a transport direction T. In other words, the plurality of the one or more electromagnets 124 may be provided as a series connection. Additionally, the one or more electromagnets 124 may be controlled individually, e.g. the one or more electromagnets can be powered individually.

[0026] In further detail, the one or more electromagnets 124 may further include one or more cores 128. The one or more coils 126 may be wound around the one or more cores 128 such that, in a cross-sectional view, one coil is provided on two sides of one core. Accordingly, the one or more coils and the one or more cores can be provided in a repetitive manner adjacent to each other. Furthermore, sections of the drive unit may include two neighboring coils next to each other.

[0027] The one or more cores 128 can include a magnetic material, i.e. a ferromagnetic material such as iron or the like. The one or more coils 126 can be provided as conductive wires being wound around the one or more cores. The electromagnets may provide a magnetic force for acting on a device next to the drive unit. In particular, the one or more electromagnets may be provided below the device and may act on magnetic counterparts arranged at the device. Thus, a movement can be provided to the device in the transport direction T.

[0028] Accordingly, a “drive unit” can be understood as a unit configured for moving a device 110 as described herein in the transport direction T. In particular, the drive unit as described herein may be configured to generate a magnetic force acting on the device, e.g. a carrier, in the transport direction T. Accordingly, the drive unit can be a linear motor. More specifically, a drive unit for moving or transporting the device can be understood as a unit configured for providing a driving force, wherein the device is moved from one position to another, different position, for example a different position along the transport direction.

[0029] For example, the device can be a carrier carrying a substrate or a mask. As explained in more detail with respect to Fig. 4, the device can be levitated by a magnetic levitation unit, i.e. by a force counteracting gravity. The device can be moved by the drive unit in the transport direction T (different from a direction parallel to gravity) while being levitated. Accordingly, the drive force may be provided in a direction different from the levitation force.

[0030] As mentioned above, the one or more electromagnets 124 may include one or more cores 128, each core of the one or more cores being arranged adjacent to a coil of the one or more coils 126. Each core may include a height ci that is larger than a height C2 of each of the coils. In other words, the one or more cores may extend from the one or more electromagnets with respect to the one or more coils. Thus, a difference in height of the one or more cores and the one or more coils may be provided.

[0031] According to embodiments described herein, the drive unit 120 includes a housing 122 and the one or more electromagnets 124 are provided within the housing. The housing includes a rib-structure 130 covering the one or more electromagnets. The housing may further include a body 123. The rib-structure may be supported by the body 123 of the housing. For example, the rib-structure and the body 123 of the housing may be connected. The housing may include a sealing between the body 123 and the rib-structure. For example, the sealing may be an O-ring for sealing the housing with respect to the surroundings. The sealing may be a vacuum-capable sealing.

[0032] Additionally, the housing may be configured to shield the one or more electromagnets, in particular, to provide a barrier between the one or more electromagnets 124 and the surroundings of the drive unit 120. In particular, the surroundings of the drive unit may include a vacuum environment. For example, the drive unit 120 can be provided in the vacuum environment, e.g. in one or more vacuum chambers of a vacuum processing system as further explained with respect to Fig. 4. Thus, the housing may be configured to shield the one or more electromagnets from the vacuum environment.

[0033] According to embodiments described herein, the rib-structure 130 may be aligned with regard to the one or more coils 126 of the one or more electromagnets 124. The rib-structure may include one or more structures extending in a common direction and may include one or more cover parts between the one or more structures. The one or more structures may be aligned with the one or more coils and the one or more cover parts may be aligned with the one or more cores. It is to be understood that, although Fig. 1 shows a rib-structure being arranged at a top of the drive unit and the one or more structures extending towards a bottom of drive unit, the drive unit may also be provided such that the rib-structure is provided at a side of the drive unit, i.e. in a plane parallel to the paper plane in Fig. 1. Accordingly, a device can be transported where the magnetic counterparts are arranged at a side of the device.

[0034] The term “rib-structure” as used throughout the present disclosure may be understood as an object having structures that can be e.g. protrusions, ribs or teeth that extend from a common base in a common direction. The extending structures can be made of the same material as the base or cover part of the rib-structure. By providing several structures extending from a common base, the rib-structure can include several maximum points or areas and minimum points or areas that alternate with respect to each other. For example, a maximum point or area of an extending structure is followed by a minimum point or area of the base, etc. Thus, the rib-structure exhibits a rake- like shape. The one or more structures may have similar maximum points or areas that also display the height of the one or more structures. The minimum points or areas represent one or more cover parts of the rib-structure, i.e. the minimum points or areas represent the height of the one or more cover parts between the one or more structures.

[0035] The expressions “extend in a common direction towards” or “extend in a common direction away from” as used throughout the present disclosure may be understood in that at least one dimension of the one or more structures of the rib-structure e.g. an extension in length or height of the one or more structures, reach to a common plane that is parallel to a plane of the housing of the drive unit, i.e. to a plane that is parallel to any of the side areas, the top area or the bottom area of the housing.

[0036] According to embodiments, the rib-structure 130 may include a non-magnetic material. For example, the rib-structure may be made of a polymer, ceramics or stainless steel. Advantageously, the rib-structure may not interfere with the electromagnets of the drive unit, i.e. the rib-structure being made of a non-magnetic material may provide good shielding properties while avoiding disturbances of the magnetic force being provided for transportation of the device.

[0037] According to embodiments that can be combined with any other embodiment described herein, the rib-structure may include a circumferential part 136. The circumferential part 136 may encompass the one or more structures of the rib-structure. The circumferential part 136 may be arranged at the body 123 of the housing i.e. the circumferential part 136 may be connected to the body 123 of the housing to provide a closed system. The circumferential part may be formed from the same material as the one or more structures. It is to be understood that the circumferential part 136 may include one or more structures, e.g. the structures being arranged at the outermost part of the rib-structure and being connected to the body of the housing. The circumferential part 136 and the body 123 of the housing may be sealed with respect to each other. For example, the housing may include a sealing, e.g. an O-ring, to seal the rib-structure and the body of the housing.

[0038] According to embodiments described herein, the rib-structure 130 includes one or more structures 132 extending in a common direction. The one or more structures may extend in a common direction towards the one or more coils 126 of the electromagnets 124. In other words, the rib-structure, e.g. the one or more structures, may fill in the spaces provided by the different heights ci and C2 of the one or more cores and the one or more coils. According to embodiments, the one or more structures may have a height di.

[0039] According to embodiments, the rib-structure may include one or more cover parts 134. The one or more cover parts may be arranged between the one or more structures i.e. the one or more cover parts may connect two neighboring structures of the one or more structures. The one or more cover parts 134 may have a height d ₂ that is smaller than a height di of the rib-structure, i.e. of the one or more structures. For example, the height d2 of the one or more cover parts may range between 0.3 to 1.5 mm, more particularly from 0.5 to 1 mm, or may even more particularly be 0.7 mm.

[0040] According to embodiments, the one or more structures may be aligned with the one or more coils 126 and the one or more cover parts 134 may be aligned with the one or more cores 128. Accordingly, the one or more cores 128 may be covered with the one or more cover parts having the height d2 and the one or more coils may be covered with the one or more structures having the height di being larger than the height d2. In other words, the one or more coils can be covered with a thicker part of the rib-structure compared to the one or more cores.

[0041] According to embodiments that can be combined with any other embodiment described herein, the height difference of height di and d2 may correspond to the difference in length of the one or more cores and the one or more coils. Thus, the one or more structures 132 can fill in the space that is formed due to the difference in length of the one or more cores and the one or more coils. Accordingly, the rib- structure may be configured to provide a thicker barrier between the one or more coils and the surroundings of the drive unit compared to the barrier between the one or more cores and the surroundings. In other words, it is to be understood that a rib-structure as described herein, beneficially provides for a membrane-like barrier which can be configured to be thinner than conventional membrane shields. Further, it is to be noted that the rib-structure can provide for a higher mechanical stability compared to conventional membrane shield solutions according to the state of the art while at the same time the thickness of the rib-structure can be reduced. In particular, such an arrangement of the rib-structure 130 may provide a greater distance between the one or more coils 126 and the one or more second magnetic counterparts 112 of the device to be transported in comparison to the distance between the one or more cores 128 and the one or more second magnetic counterparts 112 of the device.

[0042] Advantageously, the width of the gap G between the one or more cores 128 and the one or more second magnetic counterparts 112 of the device may not be limited anymore by a distance to be provided between the one or more coils and the one or more magnetic counterparts. In other words, the rib-structure provides barrier properties to the drive unit and shields the one or more coils from the surrounding environment while similarly enabling the one or more cores to come into closer contact with the one or more magnetic counterparts of the device to be transported. Further advantageously, the barrier properties of the rib-structure according to any of the embodiments described herein, provides high mechanical stability to withstand pressure differences between the housing of the drive unit and the vacuum environment. For example, inside the housing of the drive unit different pressure conditions, e.g. atmospheric pressure conditions, may exist.

[0043] According to embodiments and with exemplary reference to Fig. 2, a drive unit 220 is provided herein. The drive unit may be substantially similar to the drive unit as shown in Fig. 1. The drive unit includes a housing 122 and the one or more electromagnets 224 are provided within the housing. The housing includes a rib-structure 230 covering the one or more electromagnets. The housing may further include a body 223. It is to be understood that, although Fig. 2 shows a rib-structure being arranged at a top of the drive unit and the one or more structures extending towards a bottom of the drive unit, the drive unit may also be provided such that the rib-structure is provided at a side of the drive unit, i.e. in a plane parallel to the paper plane in Fig. 2. Accordingly, a device can be transported where the magnetic counterparts are arranged at a side of the device.

[0044] According to embodiments described herein, the electromagnets 224 include one or more cores 228. The one or more electromagnets may further include one or more coils 226. The housing 222 includes a rib-structure 230. The rib-structure includes one or more structures 232 that extend in a common direction away from the one or more electromagnets. In particular, the one or more structures may extend in a common direction away from the one or more cores 228 of the one or more electromagnets 224.

[0045] According to embodiments described herein, the rib-structure 230 may be aligned with regard to the one or more cores 128 of the one or more electromagnets 224. The rib-structure may include one or more structures 232 extending in a common direction away from the one or more cores and one or more cover parts 234 between the one or more structures. For example, the one or more structures 232 may be aligned with the one or more cores. In other words, the one or more structures may elongate the one or more cores of the electromagnets. In the embodiment as exemplarily shown in Fig. 2, the height ci of the one or more cores and the height C2 of the one or more coils may be substantially similar. However, it is to be understood that the one or more cores and coils may also include different heights. As explained with respect to Fig. 1, the rib-structure may be configured to shield the one or more electromagnets from the surroundings of the drive unit, e.g. from a vacuum environment in which the drive unit may be provided. [0046] According to embodiments described herein, the rib-structure 230 may include a ferromagnetic material. Advantageously, a magnetic force generated using the one or more electromagnets may be transferred through the one or more structures of the rib-structure. Accordingly, a magnetic force may be extended by the rib-structure 230. The rib-structure and the one or more cores may be made of the same material. [0047] According to embodiments, the rib-structure may include one or more cover parts 234.

The cover parts may be aligned with the one or more coils to shield the one or more coils from the surroundings of the drive unit 220. The one or more cover parts 234 may include a height S1 ₂ . The height h2 may be smaller than a height hi of the one or more structures. In particular, the height I12 may be chosen such that a flux of electromagnetic force through the one or more cover parts is avoided or reduced. Additionally or alternatively, the one or more coils may include a length C2 that is smaller than a height ci of the one or more cores.

[0048] Advantageously and with exemplary reference to Fig. 2, the drive unit having a rib- structure 230 where the one or more structures extend from the one or more cores 228 provides for a distance between the one or more coils 226 and a device (not shown in Fig. 2) to be transported with the drive unit that is larger than height hi of the one or more structures. Accordingly, this distance is larger than a distance between the one or more cores 228 and the device. Accordingly, the one or more cores can be brought into close contact with the device via the extension of the cores provided by the one or more structures while ensuring a distance between the one or more coils and the one or more magnetic counterparts of the device that is large enough to ensure an unimpeded transport of the device.

[0049] Further advantageously and as mentioned above, the rib-structure provides high mechanical stability to withstand pressure differences between the vacuum environment, where the drive unit may be provided, and an environment having different pressure conditions, e.g. an atmospheric environment, inside the housing of the drive unit while simultaneously providing sections of the rib-structure having a decreased thickness to enhance the drive force provided by the drive unit.

[0050] According to embodiments described herein, the rib-structure may include a circumferential part 236, the circumferential part of the rib-structure being arranged with the body 223 of the housing. The circumferential part of the rib-structure may be connected to the one or more structures 232 via the one or more cover parts 234 of the rib-structure. The circumferential part may be formed from the same material as the one or more structures. The housing may include a sealing, in particular an O-ring, to seal the rib-structure, in particular the circumferential part, with respect to the body of the housing. Additionally and as explained with respect to Fig. 1, the circumferential part 236 may include one or more structures, e.g. the structures being arranged at the outermost part of the rib-structure with respect to the body of the housing.

[0051 ] According to embodiments and with exemplary reference to Figs. 3 A and 3B, a drive unit 320 is provided. The drive unit may be substantially similar to the drive unit as shown with respect to Fig. 1. For example, the one or more cores may include a height ci that is larger than a length C2 of the one or more coils.

[0052] With respect to the embodiment shown in Figs. 3A and 3B, the rib-structure 330 may include a circumferential part 336. It is to be understood that the circumferential part 336 may include one or more structures 332, e.g. the structures being arranged at the outermost part of the rib-structure and being connected to the body 123 of the housing. In particular, the circumferential part 336 may be formed by the one or more structures, i.e. by four structures building a frame sized to fit the body 123 of the housing and additionally extending towards the one or more electromagnets. The one or more electromagnets may include one or more coils 126 and may further include one or more cores 128. The structures of the circumferential part 336 may extend towards the one or more coils. The circumferential part 336 may be supported by the body 123 of the housing 122.

[0053] According to embodiments, the rib-structure 330 may include a continuous cover part 334 being arranged with respect to the one or more cores 128. A “continuous cover part” may be understood as a section of the rib-structure that includes a height d2 being smaller than a height di of the rib-structure 330 and extending along the dimension of the drive unit 320 i.e. extending in the transport direction. As can be exemplarily seen in Fig. 3B, the continuous cover part may not be disrupted by further structures of the one or more structures. The continuous cover part 334 may be provided at a center portion of the rib-structure, i.e. the circumferential part 336 may have a continuous width at any side of the rib-structure.

[0054] Advantageously, the drive unit according to any of the embodiments described herein, may provide a vacuum-capable barrier with respect to the surroundings of the drive unit. Accordingly, the drive unit can be provided in a vacuum environment while protecting the electromagnets of the drive unit from the vacuum. [0055] Additionally, it has been found that the exertion of the magnetic force from the drive unit towards the device, i.e. the magnetic force exerted from the one or more electromagnets towards the magnetic counterparts of the device, is dependent on a width of a gap between the magnetic counterparts of the device and the one or more cores of the electromagnets of the drive unit. The smaller the width of the gap, the better the exertion of magnetic force from the drive unit to the device. Accordingly, the provision of the drive force to the device can be enhanced by lowering the width between the drive unit, i.e. the one or more cores of the electromagnets and the device.

[0056] Advantageously, the rib-structure according to embodiments described herein provides for the gap between the one or more cores of the electromagnets and the magnetic counterparts of the device that is significantly reduced such that the one or more cores of the electromagnets of the drive unit and the one or more magnetic counterparts of the device can be provided in closer spatial vicinity. Accordingly, by reducing the gap between the cores and the magnetic counterparts, the drive force towards the device can be increased and transportation of devices is more efficient and faster. In addition, the rib-structure ensures a distance between the coils of the electromagnets and the magnetic counterparts that is large enough to ensure an unimpeded transport and avoid unwanted interactions between the coils and the magnetic counterparts. Accordingly, the drive unit according to any of the embodiments described herein provides for an improved transport of devices while similarly providing vacuum-compatibility of the drive unit.

[0057] With exemplary reference to Fig. 4, a front view of a vacuum processing apparatus 450 is shown according to embodiments described herein. According to embodiments which can be combined with any other embodiment described herein, the vacuum processing apparatus 450 includes a transportation apparatus 400 and one or more vacuum chambers. A vacuum may be provided in the one or more vacuum chambers, i.e. a vacuum may be applied in the one or more vacuum chambers to generate a vacuum environment. The vacuum processing apparatus may be configured to be used in material deposition processes. For example, the vacuum processing apparatus may be used for the processing of large area substrates employed for display manufacturing deposition sources. Accordingly, the vacuum processing device may further include a processing device such as an evaporation source, a sputter source, or other processing devices used for the processing of large area substrates.

[0058] The term “vacuum” can be understood in the sense of a technical vacuum having a vacuum pressure of less than, for example, 10 mbar. Typically, the pressure in a vacuum chamber as described herein may be between 10 ⁵ mbar and about 10 ⁸ mbar, more typically between 10 ⁵ mbar and 10 ' mbar, and even more typically between about 10 ⁶ mbar and about 10 ⁷ mbar. In some embodiments, the total pressure in the one or more vacuum chambers may range from about 10 ⁴ mbar to about 10 ⁷ mbar. Accordingly, the one or more vacuum chambers can be a “vacuum deposition chamber”, i.e. a vacuum chamber configured for vacuum deposition.

[0059] According to embodiments, the transportation apparatus 400 may include a magnetic levitation unit 440 for contact! essly levitating a device 110, as exemplarily shown in FIG. 4. In particular, the magnetic levitation unit 440 is configured for holding a device 110 in a transportation space. The transportation space may be understood as a zone where the device 110 is arranged during the transport of the device in a transportation direction T along a transport path. Typically, the magnetic levitation unit 440 is arranged above the transportation space. In particular, as exemplarily shown in FIG. 4, the magnetic levitation unit 440 is arranged to interact with one or more first magnetic counterparts 411 of the device 110.

[0060] In the present disclosure, a “magnetic levitation unit” can be understood as a unit configured for holding an object, e.g. a device such as a carrier, in a contactless manner by using magnetic force. In the present disclosure, the term “levitating” or “levitation” refers to a state of an object, e.g. a carrier carrying a substrate or a mask, wherein the object floats without mechanical contact or support.

[0061] According to embodiments, which may be combined with other embodiments described herein, the magnetic levitation unit 440 may include one or more actuators 441 for contactlessly holding the device 110 in a transportation space. For instance, the one or more actuators 441 may be attached to an outside surface of an upper chamber wall 452 of the vacuum processing apparatus, e.g. of a vacuum chamber.

[0062] In the present disclosure, “contactlessly levitating” or “contactlessly holding” can be understood in the sense that a weight, e.g. the weight of a carrier, particularly the weight of a carrier carrying a substrate or a mask, is not held by a mechanical contact or mechanical forces, but is held by a magnetic force. In other words, the term “contactless” as used throughout the description can be understood in that a carrier is held in a levitating or floating state using magnetic forces instead of mechanical forces, i.e. contact forces.

[0063] In the present disclosure, an “actuator” of the magnetic levitation unit can be understood as an active and controllable element. In particular, the one or more actuators may include a controllable magnet such as an electromagnet. The magnetic field of the one or more actuators may be actively controllable for maintaining and/ or adjusting the distance between the magnetic levitation unit and the carrier. In other words, an “actuator” of the magnetic levitation unit can be understood as an element with a controllable and adjustable magnetic field to provide a magnetic levitation force acting on the device e.g. the carrier. [0064] As exemplarily shown in FIG. 4, the one or more first magnetic counterparts 411 may be arranged at a top part of the device 110. The one or more first magnetic counterparts 411 of the device may magnetically interact with the one or more actuators 441 of the magnetic levitation unit 440. In particular, the one or more first magnetic counterparts 411 can be passive magnetic elements. For instance, the one or more first magnetic counterparts 411 may be made of a magnetic material, such as a ferromagnetic material, a permanent magnet or may have permanent magnetic properties.

[0065] A “passive magnetic element” or “passive magnet” as used herein may be understood as a magnet which is not actively controlled, e.g. via a feedback control. For example, no output parameter such as a magnetic field strength of the passive magnet is controlled depending on an input parameter such as a distance. For example, a “passive magnetic element” may include one or more permanent magnets. Alternatively or additionally, a “passive magnetic element” or “passive magnet” may include one or more electromagnets which may not be actively controlled.

[0066] According to embodiments, the device 110 can be carrier, particularly a substrate carrier or a mask carrier. However, it is to be understood that the vacuum processing apparatus 450 and/or the transportation apparatus 400 as described herein may also be used for other devices employed in a vacuum processing system, e.g. processing devices such as deposition sources.

[0067] The device 110 can be moved in the vacuum processing apparatus 450 by the transportation apparatus 400 in a transport direction T, as exemplarily indicated in FIG. 4. In FIG. 4, the transport direction T is perpendicular to the paper plane. The transport direction T is typically an essentially horizontal direction (horizontal +/-10°). In the present disclosure, the term “transport direction” can be understood as the direction in which the device is transported along a transport path by the vacuum processing apparatus. The transport path can be linear or curved. Further, the transport direction may vary along the transport path. Further, in FIG. 4 the vertical direction V and the lateral direction L are indicated. [0068] Further, as exemplarily shown in FIG. 4, the transportation apparatus 400 includes a drive unit 120 for moving the device 110 ina transport direction T. The drive unit is a drive unit described according to embodiments herein. It is to be understood that the one or more electromagnets 124 of the drive unit 120 may represent a stator part of an electromagnetic linear motor. [0069] According to embodiments that can be combined with any other embodiment described herein, the housing of drive unit may be provided completely or at least partially outside the vacuum environment i.e. in an atmospheric environment such that the rib-structure may provide a barrier between the vacuum environment and the atmospheric environment. Advantageously, the rib-structure according to any of the embodiments described herein, provides high mechanical stability and thus, can withstand pressure differences between the vacuum environment and the atmospheric environment.

[0070] Further, it is to be understood that the one or more electromagnets 124 are arranged to interact with the one or more second magnetic counterparts 112 of the device 110. In particular, the one or more second magnetic counterparts 112 can be provided at a bottom of the device 110. During device transportation, the one or more second magnetic counterparts 112 move in the transport direction T passing the one or more electromagnets 124. Accordingly, the one or more electromagnets 124 can be understood as the stator of an electro-magnetic linear motor and the one or more second magnetic counterparts 112 can be understood as the mover part of the electro magnetic linear motor. For instance, the electro-magnetic linear motor may be an asynchronous linear motor.

[0071] Accordingly, it is to be understood that the one or more second magnetic counterparts 112 of the device may magnetically interact with the one or more electromagnets 124 of the drive unit 120. In particular, the one or more second magnetic counterparts 112 can be passive magnetic elements. For instance, the one or more second magnetic counterparts 112 may be made of a magnetic material, such as a ferromagnetic material, a permanent magnet or may have permanent magnetic properties.

[0072] In other words, according to embodiments which can be combined with any other embodiments described herein, the one or more electromagnets 124 are configured for moving the device in the transport direction T, particularly in a contactless manner. In particular, it is to be understood that the one or more electromagnets 124 may be actively controllable for exerting a moving force on the device 110 in the transport direction T.

[0073] Accordingly, in the present disclosure, a “transportation apparatus” can be understood as a system or apparatus configured for moving, particularly transporting, a device along a transport path in a transport direction T. In particular, the transportation apparatus may be configured for transporting an essentially vertically oriented device. “Essentially vertically” as used herein may encompass a deviation of 10° or less from an exactly vertical orientation. More specifically, the device which may be moved by the transportation apparatus can be a carrier. Accordingly, the transportation apparatus for moving a device can be a carrier transportation apparatus for moving, particularly transporting, a carrier along a transport path in a transport direction T.

[0074] According to embodiments and as mentioned above, the device 110 can be a carrier for supporting a mask or a substrate in the vacuum processing apparatus. In the present disclosure, a “carrier” can be understood as a carrying device configured for carrying an object, e.g. a substrate or a mask, through a vacuum environment. In particular, the carrier can be a substrate carrier or a mask carrier used in a processing system, e.g. for vertically processing a substrate. The carrier may include a carrier body and a holding device, e.g. a mechanical, electrostatic, or magnetic chucking device, configured for holding the object, e.g. the substrate or the mask, at an object support surface of the carrier body. The carrier may be configured to carry a large-area substrate, i.e. a substrate having a size of 1 m ² or more, particularly 5 m ² or more, or even 8 m ² or more. Transporting and holding large and heavy carriers is challenging, particularly using magnetic levitation.

[0075] In the present disclosure, the term “substrate” may particularly embrace substantially inflexible substrates, e.g., a wafer, slices of transparent crystal such as sapphire or the like, or a glass plate. However, the present disclosure is not limited thereto, and the term “substrate” may also embrace flexible substrates such as a web or a foil. The term “substantially inflexible” is understood to distinguish over “flexible”. Specifically, a substantially inflexible substrate can have a certain degree of flexibility, e.g. a glass plate having a thickness of 0.5 mm or below, wherein the flexibility of the substantially inflexible substrate is small in comparison to the flexible substrates. According to embodiments described herein, the substrate may be made of any material suitable for material deposition. For instance, the substrate may be made of a material selected from the group consisting of glass (for instance soda-lime glass, borosilicate glass etc.), metal, polymer, ceramic, compound materials, carbon fiber materials or any other material or combination of materials which can be coated by a deposition process.

[0076] As mentioned above, the device can be a substrate carrier or a mask carrier. In particular, the carrier can be a substrate carrier for large area substrates or a mask carrier for masks employed for masking large area substrates. In the present disclosure, the term “large area substrate” refers to a substrate having a main surface with an area of 0.5 m ² or larger, particularly of 1 m ² or larger. In some embodiments, a large area substrate can be GEN 4.5, which corresponds to about 0.67 m ² of substrate (0.73mx0.92m), GEN 5, which corresponds to about 1.4 m ² of substrate (1.1 m x 1.3 m), GEN 7.5, which corresponds to about 4.29 m ² of substrate (1.95 m x 2.2 m), GEN 8.5, which corresponds to about 5.7 m ² of substrate (2.2 m x 2.5 m), or even GEN 10, which corresponds to about 8.7 m ² of substrate (2.85 m x 3.05 m). Even larger generations such as GEN 11 and GEN 12 and corresponding substrate areas can similarly be implemented.

[0077] According to embodiments which can be combined with any other embodiment described herein and with exemplary reference to Fig. 5, a method for moving a device is provided. The method includes providing (represented by box 570 in Fig. 5) a drive unit having a housing and a rib-structure. The rib-structure includes one or more structures extending in a common direction and covering one or more electromagnets arranged in the housing. According to embodiments, any drive unit as described according to embodiments herein may be provided.

[0078] The method further includes moving (represented by box 580 in Fig. 5) the device by using a drive unit. According to embodiments, the drive unit may be configured to provide a translational movement to the device. In particular, the drive unit may provide a magnetic force for translationally moving the device along a transport direction.

[0079] According to embodiments described herein, the method for moving a device may be carried out in a vacuum environment. For example, the drive unit may be provided in a vacuum environment. Advantageously, the method enables moving or transporting a device while avoiding the generation of particles contaminating a vacuum process.

[0080] According to embodiments, the device may be magnetically levitated and transported along a transport direction. In particular, the device may be transported in a vacuum environment, such as in a vacuum chamber. [0081] In view of the above, it is to be understood that compared to the state of the art, embodiments of the present disclosure beneficially provide for a drive unit, a transportation apparatus, a vacuum processing apparatus and a method for moving a device which are improved with respect to vacuum-compatibility and drive efficiency of a drive unit in vacuum environments, particularly in the field of high quality display manufacturing. Further, embodiments described herein beneficially provide for a more efficient transportation of devices compared to conventional transportation apparatuses.

[0082] While the foregoing is directed to embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.