METHOD FOR CONTACTLESSLY LEVITATING A MASKING DEVICE

FIELD

Embodiments described herein relate to the contactless levitation of a masking device, more specifically a masking device for masking a substrate. More specifically, embodiments described herein relate to the contactless levitation of masking devices configured for masking large area substrates in a vertical orientation.

BACKGROUND

[0001] Several methods are known for depositing a material on a substrate. For example, substrates may be coated using an evaporation process, such as a physical vapor deposition (PVD) process, a chemical vapor deposition (CVD) process, a sputtering process, a spraying process, etc. The process can be performed in a processing chamber of a deposition apparatus, where the substrate to be coated is located. A deposition material is provided in the processing chamber. A plurality of materials, such as small molecules, metals, oxides, nitrides and carbides, may be used for deposition on a substrate. Further, other processes like etching, structuring, annealing, or the like can be conducted in processing chambers.

[0002] Coated substrates may be used in several applications and in several technical fields. For instance, an application lies in the field of organic light emitting diode (OLED) panels. Further applications include insulating panels, microelectronics, such as semiconductor devices, substrates with TFT, color filters or the like.

[0003] OLEDs are solid-state devices composed of thin films of (organic) molecules that create light with the application of electricity. OLEDs can provide bright displays on electronic devices and use less power than for instance light-emitting diodes (LEDs) or liquid crystal displays (LCDs). In the processing chamber, the organic molecules are generated (e.g., evaporated, sputtered, or sprayed etc.) and allowed to condense as thin films on the substrates. The particles pass through a mask having a specific pattern to form an OLED pattern on the substrate.

[0004] In order to reduce the footprint of deposition apparatuses, there are deposition apparatuses that allow for processing of a masked substrate in a vertical orientation. In other words, the substrate and the mask are vertically arranged within the processing chamber. It is beneficial that the mask is precisely aligned with a target positon, since a misaligned mask can lead to a deterioration of the quality of the layers deposited on the substrate. For example, for providing patterns with very small dimensions on a substrate, e.g. to manufacture an OLED, a precise alignment of the masking device is needed.

[0005] In view of the above, there is a need for methods and apparatuses which can provide an improved alignment of a masking device.

SUMMARY

[0006] According to an embodiment, a method is provided. The method includes contactlessly levitating a mask assembly. The mask assembly includes a carrier and a masking device supported by the carrier. The method includes controlling a shape of the carrier while the mask assembly is contactlessly levitated.

[0007] According to a further embodiment, a method is provided. The method includes contactlessly levitating a first mask assembly by a first plurality of magnetic levitation forces. The first mask assembly includes a first carrier and a first masking device supported by the first carrier. The method includes measuring an alignment of the first masking device while the first mask assembly is contactlessly levitated by the first plurality of magnetic levitation forces. The method includes calculating a second plurality of magnetic levitation forces. The method includes contactlessly levitating a mask assembly by the second plurality of magnetic levitation forces. The mask assembly includes a carrier and a masking device supported by the carrier. The mask assembly is the first mask assembly or a second mask assembly. The second plurality of magnetic levitation forces provide a deformation of the carrier.

[0008] According to a further embodiment, an apparatus is provided. The apparatus includes a magnetic levitation system comprising a plurality of magnetic units. The apparatus includes a mask assembly comprising a carrier and a masking device supported by the carrier. The apparatus includes a control unit connected to the plurality of magnetic units. The apparatus is configured for controlling the shape of the carrier while the mask assembly is contactlessly levitated. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] A full and enabling disclosure to one of ordinary skill in the art is set forth more particularly in the remainder of the specification including reference to the accompanying drawings wherein:

Fig. 1 illustrates a deposition process for manufacturing an OLED;

Fig. 2 shows a mask assembly in a horizontal orientation;

Fig. 3 shows a mask assembly in a horizontal orientation, the mask assembly including a mask support;

Fig. 4 shows a mask assembly in a vertical orientation;

Fig. 5 shows a mask assembly in a vertical orientation, the mask assembly including a mask support;

Figs. 6-7 illustrate a method according to embodiments described herein;

Figs. 8a-b illustrate deformations of a carrier provided by a plurality of magnetic levitation forces;

Figs. 9a-b illustrate a method according to embodiments described herein; and Figs. 10-12 illustrate an apparatus according to embodiments described herein.

DETAILED DESCRIPTION

[0010] Reference will now be made in detail to the various embodiments, 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 and is not meant as a limitation. 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.

[0011] Embodiments described herein involve contactless levitation of a mask assembly. The term "contactless" as used throughout the present disclosure can be understood in the sense that a weight of the mask assembly is not held by a mechanical contact or mechanical forces but is held by a magnetic force. Specifically, the mask assembly may be held in a levitating or floating state using magnetic forces instead of mechanical forces. In some implementations, there can be no mechanical contact between the mask assembly and the rest of the apparatus at all during levitation, and for example alignment, of the mask assembly in the system.

[0012] An advantage, as compared to mechanical devices for guiding a mask assembly in a processing system, is that contactless levitation does not suffer from friction affecting the linearity and/or precision of the positioning and alignment of the mask assembly. The contactless levitation of the mask assembly allows for a frictionless movement of the mask assembly, wherein a position of the mask assembly, e.g. relative to a substrate masked by the masking device in a deposition process, can be controlled and maintained with high precision.

[0013] For example, a contactless levitation of a mask assembly during a deposition process is beneficial in that no particles are generated due to a mechanical contact between the mask assembly and sections of the apparatus, such as mechanical rails. Accordingly, a contactless levitation provides for an improved purity and uniformity of the layers deposited on the substrate, in particular since a particle generation is minimized when using contactless levitation.

[0014] According to embodiments, which can be combined with other embodiments described herein, a deposition or coating process may be or include a thermal evaporation process, a PVD process, a CVD process and/ a sputter process. A deposition source may be provided for performing a deposition process.

[0015] In the present disclosure, the terminology of "substantially parallel" directions may include directions which form a small angle of up to 10 degrees with each other, or even up to 15 degrees. The terminology of "substantially perpendicular" directions may include directions which form an angle of less than 90 degrees with each other, e.g. at least 80 degrees or at least 75 degrees. Similar considerations apply to the notions of substantially parallel or perpendicular axes, planes, areas, orientations or the like.

[0016] Some embodiments described herein involve the notion of a "substantially vertical" direction, plane, orientation and the like. A substantially vertical direction is considered a direction substantially parallel to the direction along which the force of gravity extends. A substantially vertical direction may deviate from exact verticality (the latter being defined by the gravitational force) by an angle of, e.g., up to 15 degrees.

[0017] Embodiments described herein may further involve the notion of a "substantially horizontal" direction, plane, orientation, and the like. A substantially horizontal direction is to be understood to distinguish over a substantially vertical direction. A substantially horizontal direction may be substantially perpendicular to the exact vertical direction defined by gravity.

[0018] Fig. 1 shows a schematic view of a deposition process for manufacturing OLEDs on a substrate 10.

[0019] For manufacturing OLEDs, organic molecules are generated by a deposition source 30 (e.g., evaporated, sputtered, sprayed etc.) and deposited on the substrate 10. A masking device 20 is positioned between the substrate 10 and the deposition source 30. The masking device 20 may have a specific pattern, e.g., provided by a plurality of openings or holes 23, so that organic molecules pass through the openings or holes 23 (e.g., along a path 32) to deposit a layer or film of an organic compound on the substrate 10. A plurality of layers or films can be deposited on the substrate 10 using different masking devices or different positions of the masking device 20 with respect to the substrate 10, e.g., to generate pixels with different color characteristics. For example, a first layer or film can be deposited to generate red pixels 34, a second layer or film can be deposited to generate green pixels 36, and a third layer or film can be deposited to generate blue pixels 38. The layer(s) or film(s), e.g., an organic semiconductor, can be arranged between two electrodes, such as an anode and a cathode (not shown). At least one electrode of the two electrodes can be transparent.

[0020] The substrate 10 and the masking device 20 can be arranged in a substantially vertical orientation during the deposition process. In Fig. 1, arrows indicate a vertical direction 40 and two horizontal directions 50 and 60.

[0021] According to embodiments, which can be combined with other embodiments described herein, a masking device 20 is configured for masking a substrate 10, e.g. in a deposition process. A masking device 20 may prevent one or more portions of the substrate 10 from being coated in a deposition process. During deposition, deposition material is emitted towards a substrate 10. A masking device may be arranged in a manner such that part of the deposition material emitted towards the substrate 10 impinges on the masking device 20 to prevent that a portion of the substrate 10 is coated. [0022] According to embodiments, which can be combined with other embodiments described herein, a masking device 20 may include a plurality of openings. The plurality of openings may be configured for allowing deposition material to pass through the masking device 20 and be deposited on a substrate 10 masked by the masking device 20. The plurality of openings may define a pattern.

[0023] According to embodiments, which can be combined with other embodiments described herein, a masking device 20 may be a flexible masking device. A masking device 20 may have mechanical properties similar to a foil or sheet. A masking device 20 may be or include a sheet of masking material. A masking device 20 may be supported by a mask support, e.g. a mask frame, according to embodiments described herein.

[0024] According to embodiments, which can be combined with other embodiments described herein, a masking device 20 may be configured for masking a large area substrate.

[0025] Fig. 2 shows a mask assembly 200 according to embodiments described herein. The mask assembly 200 includes a carrier 210. The mask assembly 200 includes a masking device 20 supported by the carrier 210. The mask assembly 200 shown in Fig. 2 is substantially horizontally oriented.

[0026] According to embodiments, which can be combined with other embodiments described herein, a carrier 210 may be a carrier adapted for carrying or supporting a masking device 20. A carrier 210 may define a plane.

[0027] The carrier 210 shown in Fig. 2 is in a non-deformed state. For example, the carrier 210 may be a carrier 210 resting on a planar support in a horizontal orientation of the carrier 210. No forces acting to change the shape of the carrier 210 are applied to the carrier 210. The periphery of a non-deformed carrier may include substantially straight edges, as shown in Fig. 2. The masking device 20 shown in Fig. 2 is a non-deformed state. A non-deformed masking device 20 may have the shape of a rectangle. The periphery of a non-deformed masking device may include substantially straight edges, as shown in Fig. 2.

[0028] According to embodiments, which can be combined with other embodiments described herein, a mask assembly 200 may include a mask support. Fig. 3 shows a mask assembly 200 including a mask support 310. In the exemplary embodiment shown in Fig. 3, the mask support 310 is a mask frame. The masking device 20, e.g. a flexible masking device, is supported by the mask support 310. The masking device 20 is connected to the mask support 310, e.g. by spot welding. The mask support 310 is attached to the carrier 210, e.g. by way of one or more fasteners such as screws or bolts. The mask assembly 200 shown in Fig. 3 is provided in a substantially horizontal orientation. The carrier 210, the mask support 310 and the masking device 20 shown in Fig. 3 are in a non-deformed state. The periphery of a non-deformed mask support, e.g. mask frame, may include substantially straight edges, as shown in Fig. 3.

[0029] The parts of a mask assembly, e.g. the carrier 210, masking device 20 and/or mask support 310, may be connected to each other to assemble the mask assembly. The assembling of the mask assembly 200 may be carried out in a substantially horizontal orientation of the mask assembly 200. After assembling the mask assembly 200, the mask assembly 200 may be provided in a substantially vertical orientation, e.g. for a subsequent coating process. Before, during or after the assembling of the mask assembly 200, a substrate can be positioned and/or fixed with respect to the mask assembly 200 or masking device 20. Further devices such as at least one of a carrier, a substrate frame and a substrate holding arrangement can be provided and used in positioning and fixing the substrate.

[0030] Fig. 4 shows a mask assembly 200 including a carrier 210 and a masking device 20 according to embodiments described herein. The mask assembly 200 is provided in a substantially vertical orientation. The mask assembly 200 may include a mask support (not shown) according to embodiments described herein. For example, the masking device 20 may be a flexible masking device connected to a mask frame.

[0031] The substantially vertically oriented masking device 20 shown in Fig. 4 is in a deformed state. The shape of the masking device 20 shown in Fig. 4 is different from the shape of a non-deformed masking device, e.g. masking device 20 shown in Fig. 3. The deformed state of the masking device 20 is schematically represented in Fig. 4 by the curved shape of the upper and lower edge of the masking device 20. The deformation of the masking device 20 may be caused by the force of gravity, illustrated by arrow 450, acting on parts of the mask assembly, such as the masking device or the mask support. A deformed masking device 20 may include at least one curved edge, e.g. a curved horizontal edge.

[0032] A deformation of a masking device may be due to a connection of the masking device to a mask support, e.g. a mask frame. Fig. 5 shows a mask assembly 200 according to embodiments described herein. The mask assembly 200 is provided in a substantially vertical orientation. The mask assembly 200 includes a mask frame 510. The mask frame 510 is connected to the carrier 210 by fasteners, e.g. screws. Two fasteners 515 are shown in Fig. 5. Further fasteners may be provided. The mask assembly 200 includes a masking device 20 (not shown in Fig. 5) connected to the mask frame 510. The mask frame 510 can have one or more frame elements, such as a first frame element 522, a second frame element 524, a third frame element 526 and a fourth frame element 528.

[0033] The force of gravity acts on the mask assembly 200 and may lead to a deformation, e.g. bending, of at least a part of the mask frame 510 and/or the masking device 20. The force of gravity may in particular lead to a deformation, e.g. bending, of horizontally oriented frame elements, such as the first frame element 522 and the second frame element 524 (indicated with solid lines). The non-deformed shape of the mask frame 510 is indicated in Fig. 5 with dashed lines. The masking device 20 shown in Fig. 5 is deformed. The masking device 20 may be deformed due to the connection of the masking device 20 to the mask frame 510.

[0034] The deformed masking device and the deformed mask frame shown in the figures are depicted in a schematic manner. A deformed masking device may have a different shape as the shape shown in Fig. 4. A deformed mask frame may have a different shape to the shape shown in Fig. 5.

[0035] For example, tension forces can be present. Tension forces can affect the shape of the mask frame and/or of the masking device. Tension forces can be provided to manage thermal expansion of the mask e.g. during a deposition process. If there is sufficient tension, a temperature increase changes only the mask tension, not the pixel position.

[0036] A deformation of the masking device 20 can lead to a misalignment of the masking device 20 with respect to the substrate. The quality and/or alignment of the deposited layer(s) can be deteriorated. For example for a flexible mask attached to a mask frame, a misalignment of the masking element caused by a deformation of the mask frame may have an order of magnitude which is comparable to the size of the structures on the substrate provided by the masking device. For example, with a mask device thickness of about 50 micrometers, a mask positioning precision can be about 2 micrometers, and a vertical deformation of the masking device can be at least 2.5 micrometers.

[0037] Fig. 6 illustrates a method according to embodiments described herein.

[0038] Fig. 6 shows a plurality of magnetic units 610. Individual magnetic units of the plurality of magnetic units 610 are indicated with reference numeral 615. The plurality of magnetic units 610 provide a plurality of magnetic levitation forces 620. Individual magnetic levitation forces of the plurality of magnetic levitation forces 620 are indicated with reference numeral 625. Each magnetic levitation force 625 of the plurality of magnetic levitation forces 620 extends in a substantially vertical direction, e.g. second direction 694.

[0039] Fig. 6 shows a first direction 692. The first direction may be a substantially horizontal direction. Fig. 6 shows a second direction 694. The second direction 694 may be a substantially vertical direction.

[0040] Fig. 6 shows a mask assembly 200 including a carrier 210 and a masking device 20 supported by the carrier 210. The plurality of magnetic levitation forces 620 act on the mask assembly 200. The mask assembly 200 is contactlessly levitated by the plurality of magnetic levitation forces 620.

[0041] According to embodiments, which can be combined with other embodiments described herein, while the mask assembly 200 is contactlessly levitated, e.g., by the plurality of magnetic levitation forces 620, the carrier 210 has a substantially vertical orientation.

[0042] During contactless levitation of the mask assembly 200 by the plurality of magnetic levitation forces 620, the carrier 210 is deformed. The contactlessly levitated carrier has a different shape as compared to a non-deformed carrier.

[0043] According to embodiments, which can be combined with other embodiments described herein, a deformation of the carrier 210 may be provided by the plurality of magnetic levitation forces 620. The magnitudes of the plurality of magnetic levitation forces may be controlled, e.g. by a control unit according to embodiments described herein, to provide a target deformation of the carrier 210.

[0044] Two or more magnetic levitation forces of the plurality of magnetic levitation forces 620 may have different magnitudes. In Fig. 6, different magnitudes of the magnetic levitation forces are indicated by upward arrows having different lengths. Magnetic levitation forces having different magnitudes may provide a deformation of the carrier 210. In Fig. 6, the deformed carrier 210 includes a curved upper edge 630.

[0045] The deformation of the carrier 210 may be provided to align the masking device 20 supported by the carrier 210. The masking device 20 is mechanically coupled to the carrier 210 in a manner such that, by deforming the carrier 210, the shape, position and/or alignment of the masking device 20 can be adjusted and/or controlled.

[0046] For example, the masking device may be attached to a mask support (not shown in Fig. 6), e.g. a mask frame according to embodiments described herein. The mask support may be attached to the carrier 210. By deforming the carrier 210, the shape, position and/or alignment of the mask support connected to the carrier 210 may be adjusted and/or controlled. The connection of the masking device to the mask support allows for aligning the masking device.

[0047] In Fig. 6, the masking device 20 of the contactlessly levitated mask assembly 200 is in a well-aligned position. The masking device 20 shown in Fig. 6 has a rectangular shape. The masking device 20 is substantially non-deformed. The upper edge 640 of the masking device 20 is straight. The upper edge 640 is aligned with a reference axis 642 defining a target alignment of the masking device 20. The lower edge 650 of the masking device 20 is straight. The lower edge 650 is aligned with a reference axis 652 defining a target alignment of the masking device 20. The well-aligned position of the masking device 20 is provided by the deformation of the carrier 210 provided by the plurality of magnetic levitation forces 620.

[0048] In light of the above, a method is provided. The method includes contactlessly levitating a mask assembly 200. The mask assembly 200 may be contactlessly levitated, e.g., by the plurality of magnetic levitation forces 620. The plurality of magnetic levitation forces 620 may be provided by a plurality of magnetic units 610. The mask assembly includes a carrier 210 and a masking device 20 supported by the carrier. The masking device 20 may be adapted for masking a substrate. The method includes controlling a shape of the carrier while the mask assembly is contactlessly levitated.

[0049] By controlling the shape of the carrier 210, embodiments described herein allow for aligning the masking device 20. A misalignment of the masking device 20 can be compensated or corrected.

[0050] A misalignment, which can be corrected by the method according to embodiments described herein, may result from a deformation of the masking device 20 and/or of a mask support 310, e.g. a mask frame 510, supporting the masking device 20. For example, a vertically oriented masking device 20 may be deformed during contactless levitation since the masking device 20 is connected to a mask frame which may be bent under the influence of the gravitational force acting on the mask frame. The method according to embodiments described herein allows compensating for a deformation of the mask support. A well aligned masking device 20 can be provided by controlling the shape of the carrier. Controlling the shape of the carrier 210 may include, e.g., deforming the carrier 210 to compensate for a deformation of the mask support and/or masking device. A well aligned masking device 20 has the advantage that an improved quality of the layers deposited on the substrate can be provided.

[0051] According to embodiments, which can be combined with other embodiments described herein, the mask assembly 200 may be contactlessly levitated by a plurality of magnetic levitation forces 620. The shape of the carrier may be controlled by controlling the plurality of magnetic levitation forces 620. The shape of the carrier 210 may be controlled by controlling the magnitudes of the plurality of magnetic levitation forces 620 acting on the carrier. The shape of the carrier 210 may be controlled in a contactless manner. For example, a deformation of the carrier may be provided in a contactless manner. No mechanical parts, such as e.g. actuators, are needed for controlling the shape of the carrier 210.

[0052] According to embodiments, which can be combined with other embodiments described herein, the shape of the carrier may be controlled exclusively by contactless forces, e.g. magnetic levitation forces. A deformation of the carrier 210 may be provided exclusively by contactless forces. The deformation of the carrier 210 may be a contactless deformation.

[0053] A contactless control of the shape of the carrier has the advantage that the generation of particles can be avoided, so that the quality and purity of the layers deposited on the substrate are improved.

[0054] Further, the deformation of the carrier 210, being provided by the plurality of magnetic levitation forces 620, may be provided by suitably configuring and controlling the plurality of magnetic units 610. No additional components or devices, e.g. mechanical actuators for deforming the carrier 210, are needed to provide the deformation, which has the advantage that a simple set-up is provided and that time, energy costs and other resources can saved.

[0055] According to embodiments, which can be combined with other embodiments described herein, controlling the shape of the carrier 210 may include providing a deformation of the carrier 210. [0056] A deformed carrier 210, e.g. a carrier 210 deformed by the plurality of magnetic levitation forces 620, has a shape which differs from the shape of the carrier 210 in the case where the carrier 210 is in a non-deformed state. Magnetic levitation forces may act on the carrier 210 to change the shape of the carrier 210. A carrier 210 in a deformed state may include at least one edge having a curved shape. Particularly, a horizontal edge of the deformed carrier, e.g. upper edge 630 shown in Fig. 6, may have a curved shape. The edge in question may be straight if the carrier is in a non-deformed state. For example, Fig. 4 shows a carrier 210 in a non-deformed state, wherein the upper edge 630 is straight.

[0057] According to embodiments, which can be combined with other embodiments described herein, a deformation of the carrier 210 provided by the plurality of magnetic levitation forces 620 to align the masking device 20 may be a target deformation of the carrier 210. The plurality of magnetic levitation forces, in particular the magnitudes of the plurality of magnetic levitation forces, may be controlled, e.g. by a control unit 1010, to provide the deformation of the carrier 210.

[0058] In some implementations, controlling the shape of the carrier 210 may include maintaining the carrier 210 in a substantially non-deformed state while the carrier 210 is contactlessly levitated. In such cases, no deformation of the contactlessly levitated carrier may be provided. For example, by maintaining the carrier in a non-deformed state, an upper edge of the carrier can be kept substantially straight during contactless levitation. The masking device 20 may be configured such that the masking device 20 is well aligned when the contactlessly levitated carrier is maintained in a substantially non-deformed state.

[0059] According to embodiments described herein, the shape of the carrier may be controlled to align the masking device. For example, a deformation of the carrier 210 can be provided to align the masking device 20.

[0060] An alignment of the masking device 20 according to embodiments described herein described herein may be an alignment of the shape of the masking device 20. The shape of the carrier 210 may be controlled to align the shape of the masking device with a target shape. For example, by deforming the carrier 210, the shape of the masking device 20 may be controlled so that the masking device 20 can be brought in a non-deformed shape, e.g. a substantially rectangular shape. Aligning the masking device 20 may include controlling the shape of the masking device so that at least one edge of the masking device, e.g. a horizontal edge, is substantially straight. [0061] An alignment of the masking device 20 which involves influencing and/or controlling the shape of the masking device 20, as described herein, is different from an alignment of the masking device 20 wherein the position or orientation of the masking device is changed by merely translating or rotating the masking device without affecting the shape of the masking device. For example, an alignment of the masking device 20 wherein only the vertical position of the masking device 20 is adjusted cannot be used for controlling the shape of the masking device 20.

[0062] According to embodiments, which can be combined with other embodiments described herein, the shape of the carrier 210 may be controlled to align an edge, e.g. an upper edge 640 shown in Fig. 6, of the masking device 20 with a substantially horizontal direction, e.g. the first direction 692. For example, a deformation of the carrier 210 may be provided to align an edge of the masking device with a substantially horizontal direction.

[0063] Fig. 7 illustrates a method of aligning a masking device 20 according to embodiments described herein. Fig. 7 shows a mask assembly 200. The mask assembly 200 includes a mask frame 510. The masking device 20 is connected to the mask frame 510. The mask frame 510 is connected to the carrier 210. The deformation of the carrier 210 provided by the plurality of magnetic levitation forces 620 allows for compensating for a deformation of the mask frame 510. While the mask assembly 200 is levitated by the plurality of magnetic levitation forces 620, the mask frame and the masking device are in a substantially non-deformed state. The deformation of the carrier 210 allows for aligning the mask frame 510. For example, by providing the deformation of the carrier 210, the first frame element 522 and the second frame element 524 can be well aligned with horizontal reference axes 742 and 752, respectively. A bending of the first frame element 522 and the second frame element 524 can be compensated by the deformation of the carrier 210. The masking device 20, being connected to the mask support 310, is well aligned while the mask assembly 200 is levitated by the plurality of magnetic levitation forces 620.

[0064] According to embodiments, which can be combined with other embodiments described herein, a mask assembly 200 may include a mask support 310. The masking device 20 may be connected to the mask support. The mask support 310 may be connected to the carrier 210.

[0065] A masking device 20 may be supported by and/or attached to the mask support 310. A mask support 310 may be a rigid mask support, e.g. for supporting a flexible masking device. [0066] A mask support 310 may define a plane. A masking device 20 supported by a mask support 310 may define a plane. A plane defined by a masking device 20 supported by a mask support 310, a plane defined by the mask support 310 and/or a plane defined by a carrier supporting the masking device 20 may be parallel or substantially parallel to each other.

[0067] A mask support 310 may be a mask frame 510. A mask frame 510 may define a window or opening. An area of the window or opening may be from 60% to 100% of an area of a masking device 20 supported by the mask frame 510. A masking device 20 may be attached to a mask support 310, e.g. a mask frame, at two or more peripheral portions of the masking device 20.

[0068] A mask frame 510 may include one or more frame elements. A window defined by the mask frame 510 may be enclosed by the one or more frame elements. A frame element of a mask frame may be bar-shaped. A mask frame 510 may include a first frame element 522. A mask frame 510 may include a second frame element 524. A mask frame 510 may include a third frame element 526. A mask frame 510 may include a fourth frame element 528. The third frame element 526 may be adjacent to or connected to the first frame element 522. The second frame element 524 may be adjacent to or connected to the third frame element 526. The fourth frame element 528 may be adjacent to or connected to the second frame element. The first frame element 522 may be adjacent to or connected to the fourth frame element 528. When the mask frame 510 is in a substantially vertical orientation, e.g. while the mask assembly is contactlessly levitated as described herein, the first frame element 522 and/or the second frame element 524 may extend in a horizontal or substantially horizontal direction. When the mask frame x is in a substantially vertical orientation, the third frame element 526 and/or the fourth frame element 528 may extend in a vertical or substantially vertical direction.

[0069] A mask support 310 may be supported by a carrier 210. A mask support 310 may be attached to a carrier 210. A mask support 310 may be attached to a carrier 210 at a plurality of coupling points. A mask support 310, e.g. mask frame 510, may be attached to a carrier 210 by a plurality of fasteners, e.g. screws or bolts. For example, at least two, e.g. three or more, fasteners may be used to attach a mask frame 510 to a carrier 210. A mask support 310 may be arranged between the carrier 210 and the masking device 20.

[0070] According to embodiments, which can be combined with other embodiments described herein, a mask support 310 may be mechanically coupled to a carrier 210 in a manner such that a deformation of the carrier 210 allows for adjusting the shape, alignment and/or position of the mask support 310. For example, in the case of a mask frame attached to a carrier by a plurality of screws, the alignment of the mask support 310 can be changed by deforming the carrier 210.

[0071] According to embodiments, which can be combined with other embodiments described herein, a masking device 20 supported by a carrier 210 may be mechanically coupled to the carrier 210 in a manner such that a deformation of the carrier 210 allows for adjusting the shape, alignment and/or position of the masking device 20. For example, in the case of a flexible masking device attached to a mask frame, wherein the mask frame is attached to a carrier by a plurality of screws, the alignment of the masking device can be changed by deforming the carrier.

[0072] According to embodiments, which can be combined with other embodiments described herein, the shape of the carrier 210 may be controlled to compensate for a deformation of the mask support 310, particularly a deformation of the mask support caused by the force of gravity acting on the mask support 310. For example, a deformation of the carrier 210 may be provided to compensate for a deformation of the mask support 310.

[0073] The shape of the carrier 210 may be controlled to align a first frame element 522 of a mask frame 510 with a substantially horizontal direction, e.g. the first direction 692. For example, a deformation of the carrier 210 may be provided to compensate for a deformation of a first frame element 522. The deformation of the carrier 210 may be provided to align the first frame element 522 with a substantially horizontal direction.

[0074] According to embodiments, which can be combined with other embodiments described herein, a magnetic levitation force is a force acting on a mask assembly 200. A magnetic levitation force is configured for counteracting the force of gravity acting on the mask assembly 200. A magnetic levitation force may be provided by a magnetic unit of the plurality of magnetic units 610. A magnetic levitation force extends in a vertical or a substantially vertical direction.

[0075] According to embodiments, which can be combined with other embodiments described herein, the plurality of magnetic levitation forces 620 jointly levitate the mask assembly 200. [0076] According to embodiments, which can be combined with other embodiments described herein, the plurality of magnetic levitation forces 620 is configured for providing a deformation, particularly a target deformation, of the carrier 210. The deformation may be provided to align a masking device 20 supported by the carrier 210.

[0077] According to embodiments, which can be combined with other embodiments described herein, a plurality of magnetic levitation forces 620 may include 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or more magnetic levitation forces.

[0078] According to embodiments, which can be combined with other embodiments described herein, a first magnetic levitation force of the plurality of magnetic levitation forces 620 may be provided by a first magnetic unit of the plurality of magnetic units 610. A second magnetic levitation force may be provided by a second magnetic unit of the plurality of magnetic units. A third magnetic levitation force may be provided by a third magnetic unit of the plurality of magnetic units 610. Each magnetic unit of the plurality of magnetic units 610 may provide a magnetic levitation force of the plurality of magnetic levitation forces 620.

[0079] Each magnetic levitation force of the plurality of magnetic levitation forces 620 has a magnitude. The magnitudes of the plurality of magnetic levitation forces 620 are provided and/or controlled to provide the deformation of the carrier 210. According to embodiments, which can be combined with other embodiments described herein, at least two, particularly at least three, magnetic levitation forces of the plurality of magnetic levitation forces 620 may have different magnitudes. The different magnitudes of the plurality of magnetic levitation forces 620 may provide the deformation of the carrier 210.

[0080] A plurality of magnetic levitation forces 620 may include at least one of: a first magnetic levitation force; a second magnetic levitation force; and a third magnetic levitation force.

[0081] According to embodiments, which can be combined with other embodiments described herein, the magnitude of the first magnetic levitation force may be different from the magnitude of the second magnetic levitation force.

[0082] According to embodiments, which can be combined with other embodiments described herein, the magnitude of the second magnetic levitation force may be different from the magnitude of the first magnetic levitation force. The magnitude of the second magnetic levitation force may be different from the magnitude of the third magnetic levitation force. [0083] The magnitudes of the plurality of magnetic levitation forces 620 may have several possible distributions or profiles. The distribution of the magnitudes may depend on the target deformation of the carrier 210 which is to be provided by the plurality of magnetic levitation forces 620. Figs. 8a-b show two examples of possible distributions of the magnitudes of the plurality of magnetic levitation forces 620. Further distributions may be considered as well.

[0084] The plurality of magnetic levitation forces 620 shown in Figs. 8a-b includes magnetic levitation forces 821, 822, 823, 824 and 825. As shown in Fig. 8a, the magnitude of a magnetic levitation force 823 acting on a central portion of the carrier 210 may be larger than each of the magnitudes of magnetic levitation forces 821 and 825 acting on the outer left and outer right portions of the carrier 210, respectively. Alternatively, as shown in Fig. 8b, magnetic levitation forces 821 and 825 may each have a magnitude which is larger than a magnitude of magnetic levitation force 823.

[0085] As shown, the deformation of the carrier 210 provided by the plurality of magnetic levitation forces 620 shown in Fig. 8a is different from the deformation of the carrier 210 provided by the plurality of magnetic levitation forces 620 shown in Fig. 8b. In both cases, the deformation of the carrier 210 is provided to align the masking device 20.

[0086] Information regarding which particular distribution of the magnitudes of the magnetic levitation forces is suitable for providing a target deformation of the carrier 210 for aligning the masking device 20 may be obtained by performing one or more measurements while the mask assembly 200 is contactlessly levitated.

[0087] For example, one or more detectors, e.g. cameras, can be used to measure the alignment of the contactlessly levitated masking device. In some cases, it may be determined that a misalignment of the masking device 20 is present. The misalignment may be corrected by providing a suitable deformation of the carrier 210. Based on the measured misalignment of the masking device 20, a target distribution for the magnitudes of the magnetic levitation forces may be calculated to provide a target deformation of the carrier 210 for correcting the misalignment. The magnitudes of the magnetic levitation forces levitating the mask assembly 200 may then be adapted to match the calculated target distribution. With the target distribution in force, the magnetic levitation forces levitating the mask assembly provide the target deformation of the carrier 210. The deformation of the levitated carrier 210 compensates for the misalignment of the masking device 20 so that the masking device 20 is now well aligned. [0088] A process may involve the processing of several mask assemblies, each of which include carriers, masking devices and optionally mask supports, having e.g. a same type and size. An initial misalignment of the masking device e.g., caused by the gravitational force bending the mask support, may thus be the same misalignment for all mask assemblies being processed. Once a target deformation for one given carrier is determined for correcting the misalignment, and once a corresponding target distribution of the magnitudes of the magnetic levitation forces is calculated to provide the target deformation of that carrier, the same target distribution of the magnitudes may be applied for the subsequent mask assemblies being levitated and processed, without a need for repeating the measurement of the misalignment of the subsequent masking devices. A target distribution for the magnitudes of the magnetic levitation forces may be calculated once for one given mask assembly and thereafter be applied to a plurality of subsequent mask assemblies which are contactlessly levitated by the plurality of magnetic units.

[0089] Figs. 9a-b illustrates a method for aligning a masking device according to embodiments described herein.

[0090] Fig. 9a shows a mask assembly 200 which is contactlessly levitated by a first plurality of magnetic levitation forces 910 provided by the plurality of magnetic units 610. Individual magnetic levitation forces of the first plurality of magnetic levitation forces 910 are indicated with reference numeral 915. The first plurality of magnetic levitation forces 910 may be an initial plurality of magnetic levitation forces which is not configured for providing a deformation of the carrier 210. As shown in Fig. 9a, while the mask assembly 200 is contactlessly levitated by the first plurality of magnetic levitation forces 910, the carrier 210 may be in a substantially non-deformed state. For example, the magnitudes of the first plurality of magnetic levitation forces 910 may all be substantially the same. Each magnetic levitation force of the first plurality of magnetic levitation forces 910 may carry an equal proportion of the total weight of the mask assembly 200.

[0091] As shown in Fig. 9a, while the mask assembly 200 is contactlessly levitated by the first plurality of magnetic levitation forces 910, the masking device, and optionally a mask support 310 (not shown), may be in a deformed state, e.g. caused by the gravitational force acting on the masking device 20 and/or the mask support 310. As shown in Fig. 9a, a misalignment of the masking device 20 may be present while the mask assembly 200 is contactlessly levitated by the first plurality of magnetic levitation forces 910. In the example shown in Fig. 9a, an upper edge of the masking device 20 is not well aligned with reference axis 642. A lower edge of the masking device 20 is not well aligned with reference axis 652. The misalignment of the masking device 20 may be due to the deformed state of the masking device 20 and/or the mask support 310.

[0092] According to embodiments, which can be combined with other embodiments described herein, an alignment of the masking device and/or the mask support may be measured by one or more measuring devices, e.g. cameras or sensors. Fig. 9a shows two measuring devices 912 and 914 for measuring the alignment of the masking device. A single measuring device or two or more measuring devices may also be provided. While the mask assembly 200 is contactlessly levitated by the first plurality of magnetic levitation forces 910, the measuring device 912 and/or the measuring device 914 may be used to measure the alignment of the masking device. A misalignment of the masking device 20 may be detected. Particularly, a deviation of the shape of the masking device 20 with respect to a target shape of the masking device 20 may be determined from the measured alignment of the masking device 20.

[0093] For compensating the misalignment of the masking device 20, a target deformation of the carrier 210 may be determined. Particularly, a second plurality of magnetic levitation forces 920 may be determined. The magnitudes of the second plurality of magnetic levitation forces 920 may be calculated at least from the measured alignment of the masking device 20. The second plurality of magnetic levitation forces 920 may be configured for providing a deformation of the carrier 210 to compensate for the misalignment of the masking device 20.

[0094] Fig. 9b shows the second plurality of magnetic levitation forces 920 contactlessly levitating the mask assembly 200. The second plurality of magnetic levitation forces 920 is provided by the plurality of magnetic units 610. Individual magnetic levitation forces of the second plurality of magnetic levitation forces 920 are indicated with reference numeral 925.

[0095] As shown in Fig. 9b, while the mask assembly 200 is contactlessly levitated by the second plurality of magnetic levitation forces 920, the carrier 210 is in a deformed state. For example, the distribution of the magnitudes of the second plurality of magnetic levitation forces 920 may be non-uniform to provide a target deformation of the carrier 210. As shown in Fig. 9b, while the mask assembly 200 is contactlessly levitated by the second plurality of magnetic levitation forces 920, the masking device 20, and optionally a mask support 310 (not shown in Fig. 9b), may be in a substantially non-deformed state. As shown in Fig. 9b, while the mask assembly 200 is contactlessly levitated by the second plurality of magnetic levitation forces 920, the masking device 20 is well aligned. In the example shown in Fig. 9b, the upper edge of the masking device 20 is aligned with reference axis 642. The lower edge of the masking device 20 is aligned with reference axis 652.

[0096] As described above, once the magnitudes of the second plurality of magnetic levitation forces 920 are calculated for the masking device 20, the second plurality of magnetic levitation forces may also be applied for levitating and aligning one or more further mask assemblies, without the need for repeating the measurement of the misalignment and the calculation of the distribution of the magnetic levitation forces.

[0097] According to an embodiment, a method of aligning a masking device is provided. The method includes contactlessly levitating a first mask assembly, e.g. mask assembly 200, by a first plurality of magnetic levitation forces 910. The first mask assembly includes a first carrier and a first masking device supported by the first carrier. The first plurality of magnetic levitation forces may be provided by a plurality of magnetic units 610. The method includes measuring an alignment of the first masking device while the first mask assembly is contactlessly levitated by the first plurality of magnetic levitation forces 910. The method includes calculating, particularly from at least the measured alignment of the first masking device, a second plurality of magnetic levitation forces 920. The second plurality of magnetic levitation forces 920 may be calculated for the plurality of magnetic units 610. For example, the method may include calculating the magnitudes of the second plurality of magnetic levitation forces 920 from at least the measured alignment of the first masking device. The method includes contactlessly levitating a mask assembly by the second plurality of magnetic levitation forces 920. The mask assembly includes a carrier and a masking device supported by the carrier. The mask assembly is the first mask assembly or a second mask assembly. The second plurality of magnetic levitation forces 920 provide a deformation of the carrier. For example, the deformation of the carrier can be provided to align the masking device.

[0098] The first mask assembly according to embodiments described herein may be the mask assembly 200 according to embodiments described herein. The first carrier according to embodiments described herein may be the carrier 210 according to embodiments described herein. The first masking device according to embodiments described herein may be the masking device 20 according to embodiments described herein. The first mask assembly may include the mask support 310 according to embodiments described herein. Features and aspect described herein in relation to the mask assembly 200, the carrier 210 and the masking device 20 according to embodiments described herein also apply to the first mask assembly, the first carrier and the first masking device according to embodiments described herein.

[0099] The second plurality of magnetic levitation forces 920 according to embodiments described herein may be the plurality of magnetic levitation forces 620 according to embodiments described herein. The second mask assembly according to embodiments described herein may be the mask assembly 200 according to embodiments described herein. The second mask assembly may include the carrier 210, the masking device 20 and/or the mask support 310 according to embodiments described herein. Features and aspects described herein in relation to the plurality of magnetic levitation forces 620 and the mask assembly 200 also apply to the second plurality of magnetic levitation forces 920 and the second mask assembly according to embodiments described herein.

[00100] According to embodiments, which may be combined with other embodiments described herein, at least two magnetic levitation forces of the second plurality of magnetic levitation forces may have different magnitudes.

[00101] According to embodiments, which may be combined with other embodiments described herein, the method may include determining, from at least the measured alignment of the first masking device, a deviation of the shape of the first masking device from a target shape. The shape of the first masking device, for which the deviation is determined, may be the shape of the first masking device during contactless levitation of the first masking device by the first plurality of magnetic levitation forces 910. A target shape may be the shape of a substantially non-deformed first masking device.

[00102] According to embodiments, which may be combined with other embodiments described herein, the second plurality of magnetic levitation forces 920 are provided for contactlessly levitating the first mask assembly. The method may include changing from the first plurality of magnetic levitation forces to the second plurality of magnetic levitation forces while the first mask assembly is contactlessly levitated.

[00103] According to a further embodiment, and as illustrated in Fig. 10, an apparatus 1000 is provided. The apparatus 1000 includes a magnetic levitation system including a plurality of magnetic units 610. The apparatus 1000 includes a mask assembly 200. The mask assembly 200 includes a carrier 210 and a masking device 20 supported by the carrier. The apparatus 1000 includes a control unit 1010 connected to the plurality of magnetic units 610. The apparatus 1000 is configured for controlling the shape of the carrier 210 while the mask assembly 200 is contactlessly levitated.

[00104] According to embodiments, which can be combined with other embodiments described herein, the control unit 1010 may be configured for controlling the plurality of magnetic units 610 to control the shape of the carrier 210 while the mask assembly 200 is contactlessly levitated.

[00105] According to embodiments, which can be combined with other embodiments described herein, the plurality of magnetic units 610 may be configured for providing a plurality of the magnetic levitation forces 620 to contactlessly levitate the mask assembly 200. The control unit 1010 may be configured for controlling the plurality of magnetic levitation forces 620 to control the shape of the carrier 210, e.g. to provide a deformation of the carrier 210. The control unit 1010 may be configured for controlling the plurality of magnetic levitation forces 620 to provide a deformation of the carrier 210 to align the masking device 20.

[00106] The apparatus 1000 according to embodiments may be adapted for performing any of the method features according to embodiments of the methods described herein, particularly any of the features described in the dependent method claims. A control unit as described herein may be adapted for performing any of the method features of embodiments of the methods described herein, particularly any of the features described in the dependent method claims.

[00107] According to embodiments, which can be combined with other embodiments described herein, a plurality of magnetic units 610 may include a first magnetic unit. A plurality of magnetic units 610 may include a second magnetic unit. A plurality of magnetic units 610 may include a third magnetic unit. A plurality of magnetic units 610 may include further magnetic units. A plurality of magnetic units 610 may include 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or more magnetic units. For example, the plurality of magnetic units 610 may include from 5 to 20 magnetic units in one degree of freedom.

[00108] According to embodiments, which can be combined with other embodiments described herein, any magnetic unit of the plurality of magnetic units 610 may be an active magnetic unit. The plurality of magnetic units 610 may be a plurality of active magnetic units. [00109] According to embodiments, which can be combined with other embodiments described herein, an active magnetic unit may be configured for generating a magnetic field for providing a magnetic levitation force extending in a vertical direction, e.g. second direction 694 shown in the figures. An active magnetic unit can be controlled to provide an adjustable magnetic field. The adjustable magnetic field may be a static or a dynamic magnetic field. An active magnetic unit may be or include an element selected from the group consisting of: an electromagnetic device; a solenoid; a coil; a superconducting magnet; or any combination thereof.

[00110] The terminology of an "active" magnetic unit is used herein to distinguish from the notion of a "passive" magnetic unit. A passive magnetic unit may refer to an element with magnetic properties, which are not subject to active control or adjustment, at least not during operation of the apparatus. For example, the magnetic properties of a passive magnetic unit may not be subject to active control during contactless levitation of the mask assembly. A passive magnetic unit may be a magnetic material, such as a ferromagnetic material, a permanent magnet or may have permanent magnetic properties.

[00111] As compared to a passive magnetic unit, an active magnetic unit offers more flexibility and precision in light of the adjustability and controllability of the magnetic field generated by the active magnetic unit.

[00112] While a mask assembly 200 is contactlessly levitated by the plurality of magnetic units 610, the plurality of magnetic units 610 may be arranged above the mask assembly 200.

[00113] According to embodiments, which can be combined with other embodiments described herein, the apparatus 1000 may include one or more measuring devices, e.g. measuring devices 912 and 914 shown in Fig. 11. The one or more measuring devices may be configured for measuring an alignment of the masking device 20 and/or of the mask support 310. The one or more measuring devices may be configured for measuring an alignment of the masking device 20 and/or mask support 310 while the mask assembly 200 is contactlessly levitated by the plurality of magnetic units 610. The control unit 1010 may be connected to the one or more measuring devices. The control unit 1010 may be configured for calculating the magnitudes of the plurality of magnetic levitation forces 620. The magnitudes may be calculated at least based on an alignment of the masking device 20 measured by the one or more measuring devices. [00114] According to embodiments, which can be combined with other embodiments described herein, the apparatus 1000 may include a processing chamber 1120. Fig. 11 shows a processing chamber 1120. The plurality of magnetic units 610 may be arranged in the processing chamber 1120. The one or more measuring devices, e.g. measuring devices 912 and/or 914, may be arranged in the processing chamber 1120.

[00115] A processing chamber 1 120 may be a vacuum chamber. A processing chamber may be a vacuum deposition chamber.

[00116] According to embodiments, which can be combined with other embodiments described herein, the apparatus 1000 may include a deposition source, particularly a deposition source for coating a substrate masked by the masking device 20. During coating, the substrate may be supported by the carrier 210 or by a further carrier. During coating, the substrate may be contactlessly levitated. The deposition source may be arranged in the processing chamber 1120. A deposition source may include a target, e.g. with deposition material thereon, or any other arrangement allowing material to be released for deposition on a substrate. A deposition source may include a rotatable target. The deposition material may be chosen according to the deposition process and the later application of the coated substrate. For example, the deposition material can be an organic material used in the manufacture of OLEDs. For instance, the deposition material of a deposition source may be a material including small molecules, polymers, and phosphorescent materials. For example, the deposition material can be selected from the group including, chelates (e.g., Alq ₃ ), fluorescent and phosphorescent dyes (e.g., perylene, rubrene, quinacridone derivatives, etc) and conjugated dendrimers.

[00117] Fig. 12 shows an apparatus 1000 according to embodiments described herein. The apparatus 1000 shown in Fig. 12 includes a magnetic levitation system including a plurality of magnetic units 610, e.g. active magnetic units such as electromagnetic devices, solenoids, coils or superconducting magnets. The magnetic levitation system extends in a first direction 692, which may be a substantially horizontal direction. The mask assembly 200 may be movable in the first direction 692 with respect to the plurality of magnetic units 610. As shown in Fig. 12, the mask assembly 200 may be connected to, e.g. attached to, a first passive magnetic unit 1210, e.g. a bar of ferromagnetic material.

[00118] According to embodiments, which can be combined with other embodiments described herein, a mask assembly 200 may be connected to one or more magnetic units, e.g. a first passive magnetic unit 1210 as shown in Fig. 12. A magnetic levitation force acting on the mask assembly 200 may be provided by an interaction of a magnetic field provided by the plurality of magnetic units 610, e.g. active magnetic units, with the magnetic properties of the one or more magnetic units, e.g. the first passive magnetic unit 1210, connected to the mask assembly 200. The interaction provides for a magnetic attraction between the plurality of magnetic units 610 and the first passive magnetic unit 1210. The magnetic attraction provides for an upward force acting on the first passive magnetic unit 1210. The mask assembly 200, being connected to the first passive magnetic unit 1210, is contactlessly levitated by the upward force.

[00119] For example, the carrier 210 of the mask assembly 200 may be mechanically coupled, e.g. attached, to the first passive magnetic unit 1210. The plurality of magnetic levitation forces 620 may act on the carrier 210 via the mechanical coupling of the carrier 210 to the first passive magnetic unit 1210. The action of the plurality of magnetic levitation forces 620 on the carrier 210, via the connection of the carrier 210 to the first passive magnetic unit 1210, can be controlled to provide a deformation of the carrier 210. For example, by providing a plurality of magnetic levitation forces 620 with different magnitudes, upward forces acting on the carrier 210 may be provided, wherein the upward forces have different magnitudes along the length of the carrier 210 in the first direction 692. The upward forces with different magnitudes can be configured for providing a target deformation of the carrier 210.

[00120] According to embodiments, which can be combined with other embodiments described herein, a plurality of magnetic units 610 may be arranged in a first direction 692. The plurality of magnetic units 610 may be a linear array of magnetic units extending in the first direction 692.

[00121] The plurality of magnetic levitation forces 620 may be spaced apart from each other in a first direction 692. A first magnetic levitation force of the plurality of magnetic levitation forces may be spaced apart from a second magnetic levitation force of the plurality of magnetic levitation forces in the first direction 692. A third magnetic levitation force of the plurality of magnetic levitation forces may be spaced apart from the second magnetic levitation force in the first direction 692.

[00122] According to embodiments, which can be combined with other embodiments described herein, the plurality of magnetic units 610 may extend in a first direction 692. The plurality of magnetic levitation forces may include a first magnetic levitation force and a second magnetic levitation force. The second magnetic levitation force may be spaced apart from the first magnetic levitation force in the first direction 692. A magnitude of the second magnetic levitation force may be different from a magnitude of the first magnetic levitation force. The plurality of magnetic levitation forces 620 may include a third magnetic levitation force spaced apart from the second magnetic levitation force in the first direction 692.

[00123] According to embodiments, which can be combined with other embodiments described herein, a substrate 10 may be a large area substrate. A large area substrate may have a size of at least 0.67 m ² . The size may be from about 0.67m (0.73x0.92m - Gen 4.5) to about 8 m ² , more specifically from about 2 m ² to about 9 m ² or even up to 12 m ² . For instance, a large area substrate can be GEN 4.5, which corresponds to about 0.67 m ² substrates (0.73x0.92m), GEN 5, which corresponds to about 1.4 m ² substrates (1.1 m x 1.3 m), GEN 7.5, which corresponds to about 4.29 m ² substrates (1.95 m x 2.2 m), GEN 8.5, which corresponds to about 5.7m ² substrates (2.2 m x 2.5 m), or even GEN 10, which corresponds to about 8.7 m ² substrates (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.

[00124] The term "substrate" as used herein embraces both inflexible substrates, e.g., a glass substrate, a wafer, slices of transparent crystal such as sapphire or the like, or a glass plate, and flexible substrates, such as a web or a foil. According to embodiments, which can be combined with other embodiments described herein, embodiments described herein can be utilized for Display PVD, e.g. sputter deposition on large area substrates for the display market.

[00125] While the foregoing is directed to embodiments of the disclosure, other and further embodiments may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.