Patent Application
20100095892
Embodiments of the invention generally relate to an evaporator device, particularly for evaporating materials, such as metals. More particularly, embodiments of the invention relate to an evaporator device, a method of mounting an evaporator device, a method of operating an evaporator device, and a coating device.
Evaporator devices have many functions in a plurality of industrial fields, including, but not limited to, thin-film deposition applications in the production of displays, solar wafer manufacturing or in semiconductor device production. A typical evaporation deposition application is PVD (Physical Vapor Deposition).
In a typical PVD application, an evaporation crucible, which is provided with a material to be evaporated, is heated, for instance in a vacuum atmosphere, to the evaporating temperature of the material. Thereby, particles of the material are vaporized and travel towards a substrate to be coated.
Typical evaporator devices may include a housing encompassing an evaporator, on which the evaporation crucible may be supported and heated. The housing typically has an evaporation aperture for releasing the vapor produced inside of the housing towards the substrate to be coated. At the inner walls of the housing a shielding may be mounted, e.g. by screws. The shielding screens the inner walls of the housing from vapor particles and, in addition, from the heat emitted from the crucible. However, during evaporation, the shielding may also be heated, and therefore may deteriorate. Hence, in some cases, the shielding mounted at the inner walls of the housing is cooled. However, such cooling of the shielding may not be effective. Furthermore, during evaporation, the shielding is also coated with the vapor particles. Hence, from time to time, the coated shielding has to be replaced by an uncoated shielding, which may be a time consuming procedure requiring expensive materials.
In light of the above, an evaporator device according to independent claim 1, a method of mounting an evaporator device according to independent claim 13, a method of operating an evaporator device according to independent claim 14, and a coating device according to independent claim 15 are provided.
According to one embodiment, an evaporator device is provided, including a frame having an opening and being connectable to a cooling unit for cooling the frame, an evaporator being adapted for supporting an evaporator crucible within the frame, and a shielding frame, wherein the shielding frame is substantially concentrically within and adjacent to the frame detachably installable through the opening of the frame.
According to another embodiment, a method of mounting an evaporator device is provided, including providing an evaporator device having a frame having an opening and being connectable to a cooling unit for cooling the frame, an evaporator being adapted for supporting an evaporator crucible within the frame, and a shielding frame, wherein the shielding frame is substantially concentrically within and adjacent to the frame detachably installable through the opening of the frame, arranging the shielding frame substantially concentrically within and adjacent to the frame, and optionally installing an evaporator crucible at the evaporator.
According to a further embodiment, a method of operating an evaporator device is provided, including providing an evaporator device having a frame having an opening and being connectable to a cooling unit for cooling the frame, an evaporator being adapted for supporting an evaporator crucible within the frame, and a shielding frame, wherein the shielding frame is substantially concentrically within and adjacent to the frame detachably installable through the opening of the frame, the evaporator device having the shielding frame installed substantially concentrically within and adjacent to the frame, and having an evaporator crucible provided at the evaporator, cooling the frame, and heating the evaporator crucible.
According to a yet further embodiment, a coating device is provided, including an evaporator device having a frame having an opening and being connectable to a cooling unit for cooling the frame, an evaporator being adapted for supporting an evaporator crucible within the frame, and a shielding frame, wherein the shielding frame is substantially concentrically within and adjacent to the frame detachably installable through the opening of the frame, the evaporator device having the shielding frame installed substantially concentrically within and adjacent to the frame, and having an evaporator crucible provided at the evaporator.
Further features and details are evident from the dependent claims, the description and the drawings.
Embodiments are also directed to apparatuses for carrying out the disclosed methods and including apparatus parts for performing described method steps. Furthermore, embodiments are also directed to methods by which the described apparatus operates or by which the described apparatus is manufactured. It may include method steps for carrying out functions of the apparatus or manufacturing parts of the apparatus. The method steps may be performed by way of hardware components, firmware, software, a computer programmed by appropriate software, by any combination thereof or in any other manner.
It is contemplated that elements of one embodiment may be advantageously utilized in other embodiments without further recitation.
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of embodiments of the invention, briefly summarized above, may be had by reference to embodiments. The accompanying drawings relate to embodiments of the invention and are described in the following. Some of the above mentioned embodiments will be described in more detail in the following description of typical embodiments with reference to the following drawings in which:
a to 1c show cross sectional views of an evaporator device according to one example of embodiments disclosed herein;
a to 2c show cross sectional views of an evaporator device according to another example of embodiments disclosed herein;
Reference will now be made in detail to the various embodiments, one ore more examples of which are illustrated in the figures. Each example is provided by way of explanation, and is not meant as a limitation of the invention.
Without limiting the scope, in the following, an evaporator device and corresponding methods of mounting and of operating an evaporator device according to embodiments disclosed herein are described, referring to an Aluminum evaporator. However, other materials, e.g. metals, metal alloys or plastic materials may be evaporated using the evaporator device of embodiments described herein. In particular, materials which may be provided to the evaporator as a wire may be vaporized with the evaporator device of embodiments described herein. Moreover, without limiting the scope of the present application, the following description refers to embodiments of an evaporator device which may be used in vacuum atmosphere.
Within the following description of the drawings, the same reference numbers refer to the same components. Generally, only the differences with respect to the individual embodiments are described. Further, in the following, the frame of the evaporator device may also be referred to as cooling frame. Moreover, the evaporator crucible may be referred to herein as crucible or evaporation crucible.
Typical applications of embodiments described herein are for example evaporation deposition applications in the production of displays, such as LCD, TFT, and OLED (Organic Light Emitting Diode) displays, solar wafer manufacturing and in semiconductor device production. Furthermore, typical substrates, which may be coated using the evaporator device according to embodiments disclosed herein, may be rigid or flexible, e.g. rigid glass substrates or flexible films, such as webs.
According to one embodiment, an evaporator device is provided, including: a frame having an opening and being connectable to a cooling unit for cooling the frame, an evaporator being adapted for supporting an evaporation crucible within the frame, and a shielding frame, wherein the shielding frame is substantially concentrically within and adjacent to the frame detachably installable through the opening of the frame.
According to embodiments disclosed herein, the shielding frame and the frame have the same three-dimensional form and the shielding frame has a smaller volume than the frame. For instance, the outer dimensions of the shielding frame may be smaller than the inner dimensions of the frame, such that at non-operating temperatures of the evaporator device, e.g. at ambient temperature, a clearance between the frame and the shielding frame is provided. In some embodiments, the shielding frame and the frame may be tubes, e.g. rectangular tubes or circular tubes.
a to 1c illustrate cross sectional views of an evaporator device 1 according to one example of embodiments disclosed herein.
Typically, the evaporator device 1 includes a cooling frame 10, a shielding frame 20 and an evaporator 30. In one example of embodiments disclosed herein, the cooling frame 10 and the shielding frame 20 may be rectangular tubes. Hence, in the example of
In the example as shown in
In a typical example of embodiments, the cooling frame 10 is vacuum tight and may be mounted, e.g. welded, at its front side 16 to a vacuum flange 14, as illustrated in
According to one example of embodiments, as shown in
Furthermore, the cooling frame 10 may be connected to a cooling unit 40, as shown in
According to embodiments disclosed herein, the evaporator device includes a shielding frame, which is detachably installable within the cooling frame through an opening thereof. Typically, the shielding frame is installable substantially concentrically within and adjacent to the cooling frame.
According to one embodiment, the opening of the frame is provided at the evaporation side of the evaporator device and the shielding frame has an opening and is installable within the frame such that the opening of the shielding frame is provided at the evaporation side of the evaporator device.
As an example of embodiments disclosed herein,
In embodiments disclosed herein, the shielding frame has a structure adapted for providing, when installed within the frame, a clearance to the frame at a non-operating temperature of the evaporator device and a close fit with the frame at an operating temperature of the evaporator device. Typically, the shielding frame may have a structure adapted for providing a clearance to the frame at a non-operating temperature of the evaporator crucible and a close fit with the frame at an operating temperature of the evaporator crucible. Alternatively or in addition, the shielding frame may have a structure adapted for providing a clearance to the frame at a non-operating temperature of the cooling unit and a close fit with the frame at an operating temperature of the cooling unit.
According to the example of embodiments shown in
In examples of embodiments disclosed herein, the cooling frame 10, e.g. as shown in
The cooling frame 10 including the flange 14 may have a total outside length in a range of about 220 cm to about 50 cm, typically of about 125 cm. A typical outside width and/or outside height of the cooling frame 10 may be in a range of about 20 cm to about 50 cm, typically about 37 cm. In case of a cooling frame 10 having a square cross section, the outside cross sectional dimensions of the cooling frame may typically be about 37 cm×about 37 cm.
In some embodiments disclosed herein, the material of at least one of the shielding frame and the cooling frame may have a linear thermal expansion coefficient in the range of 5×10−6/K to 45×10−6/K at 20° C., typically in the range of 10×10−6/K to 20×10−6/K at 20° C. Alternatively or in addition, the material of at least one of the shielding frame and the cooling frame may have a volumetric thermal expansion coefficient in the range of 10×10−6/K to 90×10−6/K at 20° C., typically in the range of 30×10−6/K to 60×10−6/K at 20° C.
The linear thermal expansion of a material is the one-dimensional change with temperature and can be written:
wherein ΔL is the change in length after thermal expansion, L0 is the original length, ΔT is the change of temperature, and αL is the linear thermal expansion coefficient.
The change in volume with temperature, i.e. the volumetric thermal expansion of a material can be written:
wherein ΔV is the change in volume after thermal expansion, V0 is the original volume, ΔT is the change of temperature, and αV is the volumetric thermal expansion coefficient.
For instance, according to a typical example of embodiments, the shielding frame 20 and the cooling frame 10 consist of vacuum compatible stainless steel, which e.g. has a linear thermal expansion coefficient of 17.3×106/K at 20° C. and a volumetric thermal expansion coefficient in the range of 51.9×10−6/K at 20° C. Moreover, the cooling frame 10, an example of which is shown in
Therefore, at ambient temperature, there is a clearance between the shielding frame 20 and the cooling frame 10 of the evaporator device 1 when they are assembled. Hence, the shielding frame 20 can be installed within cooling frame 10 by arranging the shielding frame 20 in the opening 18 of the cooling frame 10 and pushing it along the longitudinal direction of the cooling frame 10 up to the lid 19. Typically, the opening 26 of the shielding frame 20 forms the evaporation opening of the evaporator device 1. When the evaporator device is operated, the cooling frame 10 is cooled, and an evaporator crucible (not shown) installed in recess 32 of the evaporator 30 is heated, e.g. to more than about 1300° C. in a high vacuum atmosphere. Hence, the shielding frame 20 expands in correspondence with the linear and volumetric expansion coefficient of the material of the shielding frame 20. Moreover, the cooling frame 10 may shrink in correspondence with the linear or volumetric expansion coefficient of the material of the cooling frame 10. Thereby, at operating temperatures of the evaporator device 1, the shielding frame 20 has a close fit with the cooling frame 10, as shown in
In one example of embodiments disclosed herein, shielding frame 20 protrudes from the opening 18 of the cooling frame 10, as shown in
According to examples of embodiments disclosed herein, the evaporator is mounted at an inner wall of the cooling frame. Furthermore, the shielding frame may have at least one recess for receiving the evaporator.
In one typical variation of the example shown in
In some embodiments disclosed herein, the cooling frame 10 and the shielding frame 20 of the evaporator device may be circular tubes. For instance,
The example of
Typical inner diameter of the cooling frame 110 may be in the range of about 50 mm to about 1250 mm, typically about 200 to about 700 mm. Moreover, the outer diameter of the shielding frame 120 may be smaller, e.g. in a range of about 0.2 mm to about 160 mm smaller, than the corresponding inner dimensions of cooling frame 10, depending on the linear or volumetric expansion coefficient of the shielding material and/or the cooling frame material. The thickness of the walls of the cooling frame 110 and/or of the shielding frame 120 may be in a range of about 3 mm to about 100 mm, typically of about 6 mm. In one typical example, the shielding frame 200 may have an internal diameter of about 20 cm. The length, i.e. the dimension along the longitudinal axis of the evaporator device, of the cooling frame 100 and/or the shielding frame 200 may be in a range of about 50 cm to about 200 cm, typically about 125 cm.
The cooling frame 100 including the flange 140 may have a total outside length in a range of about 220 cm to about 50 cm, typically of about 125 cm. A typical external diameter of the cooling frame 100 may be in a range of about 20 cm to about 50 cm, typically about 37 cm.
For instance, according to a typical example of embodiments disclosed herein, the shielding frame 120 and the cooling frame 110 consist of vacuum compatible stainless steel, which e.g. has a linear thermal expansion coefficient of 17.3×10−6/K at 20° C. and a volumetric thermal expansion coefficient in the range of 51.9×10−6/K at 20° C. Moreover, the cooling frame 110 may have an inner diameter of e.g. about 10 cm. Further, the shielding frame 20 may have an outer diameter which is e.g. about 4 mm smaller than the inner diameter of cooling frame 10.
Therefore, at ambient temperature, there is a clearance between the shielding frame 120 and the cooling frame 110 of the evaporator device 100 when they are assembled. Hence, the shielding frame 120 can be installed within cooling frame 10 by arranging the shielding frame 120 in the opening 18 of the cooling frame 110 and pushing it along the longitudinal direction of the cooling frame 110 up to the back side lid thereof. However, when the evaporator device is operated, the cooling frame 110 is cooled, and an evaporator crucible (not shown) installed in recess 32 of the evaporator 30 is heated, e.g. to about 1300° C. Hence, the shielding frame 120 expands in correspondence with the linear and volumetric expansion coefficient of the material of the shielding frame 120. Moreover, the cooling frame 110 may shrink in correspondence with the linear or volumetric expansion coefficient of the material of the cooling frame 110. Thereby, at operating temperatures of the evaporator device 100, the shielding frame 120 has a close fit with the cooling frame 110, such that the outer wall of the shielding frame 120 is in close contact to the inner wall of the cooling frame 110. As a result, a large area of the shielding frame 120 is cooled. Hence, the cooling is more effective as compared to a shielding mounted via a few screws at a distance to the cooling frame. Moreover, the shielding frame 120 is fixed inside of the cooling frame 110 during operation of the evaporator device. In addition, at non-operating temperatures, e.g. at ambient temperature, an easy and quick installation or exchange of the shielding frame is possible. Further, the structure of evaporator device 100 is simple and allows mounting and dismounting of the shielding without using installation tools or screws.
Typically, in a vacuum atmosphere, the evaporator device of embodiments disclosed herein produces a vapor cloud which may have a clubbed shape. When the evaporator device of embodiments disclosed herein is mounted via a vacuum flange, e.g. vacuum flange 14, at a vacuum coating chamber, the vapor cloud produced during evaporation may extend from the opening 26 of the shielding frame 20 into the coating chamber. For instance, at its maximum extension, the vapor cloud may have a diameter of up to about 1000 mm, typically of about 300 mm to about 800 mm, more typically of about 500 mm to about 600 mm.
A typical example of materials which may be evaporated using the evaporator devices 1 and 100 is Aluminum. However, other materials, such as other metals, e.g. Magnesium or Tin, metal alloys or plastics, may be contemplated. Typically, the material or materials to be evaporated may be provided in the form of a wire or wires, respectively.
According to one example of embodiments disclosed herein, the evaporator device includes a wire chamber adapted for continuously or discontinuously feeding a wire of material to be evaporated into the evaporator. Hence, according to another example of embodiments disclosed herein, during operation of the assembled evaporator device of embodiments disclosed herein, the wire may be continuously or discontinuously fed into the evaporator. Typically, the wire may be continuously fed into an evaporator crucible mounted in recess 32 of the evaporator 30. For instance, the wire may be introduced into the interior of the shielding frame 20 through the front side opening 26 of the shielding frame 20. As mentioned above, in some examples, the front side opening of the shielding frame is the evaporation opening of the evaporator device. That means, the wire may be introduced into the evaporator device through the evaporation opening. For example, a so called wire chamber may be mounted next to the evaporator device, e.g. at an extension of the flange 14 or 140. The wire chamber may by designed for encompassing a coil of the wire and continuously or discontinuously uncoiling the wire. Hence, the wire may be continuously or discontinuously transported into the crucible from the wire chamber which is mounted next to the evaporator device. Therefore, the feeding of the wire may be performed at the evaporation side of the evaporator device. In a variation of this example, e.g. in case that the shielding frame 20, 120 protrudes from the opening 18 of the cooling frame 10, 110, as shown in
According to an alternative example, as illustrated in
In a further example of embodiments disclosed herein, a method of mounting an evaporator device is provided, including providing an evaporator device according to any of the examples described above, arranging the shielding frame substantially concentrically within and adjacent to the frame, and optionally installing an evaporation crucible at the evaporator.
For instance, in a typical example of a method for mounting the evaporator device, described referring to the example shown in
Further, according to embodiments disclosed herein, because of the clearance between the shielding frame and the cooling frame of the assembled evaporator device at non-operating temperatures, the shielding frame can be easily exchanged. This may for instance be done by releasing the crucible from the evaporator recess 32, thereby releasing the electrical connectors 33, dismounting the evaporator 30 and removing the shielding frame 20 or 120 from the cooling frame 10 or 110, respectively, through the opening 18 of the cooling frame.
The removed shielding frame may then be discarded, if the material of the shielding frame is inexpensive. Alternatively, e.g. if the material of the shielding frame is expensive, the exchanged shielding frame may be restored by a cleaning procedure and may be mounted again in the evaporator device. For instance, a shielding frame made of vacuum compatible stainless steel and used during evaporation of Aluminum can be cleaned by treating it with an alkaline solution, e.g. NaOH.
In other examples of embodiments disclosed herein, as mentioned e.g. with respect to
In one embodiment, a method of operating an evaporator device, is provided, including providing an evaporator device according to any of the examples described above, the evaporator device having the shielding frame installed substantially concentrically within and adjacent to the frame, having an evaporator crucible provided at the evaporator, and optionally having the frame connected to the cooling unit, cooling the frame, and heating the evaporator crucible.
Hence, in one example of a method of operating an evaporator device according to embodiments disclosed herein, after mounting the evaporator device 100 as described above e.g. in a coating chamber, a vacuum may be established in the coating chamber, if necessary. Then, the cooling unit is started and the cooling frame 110 is cooled. After that, the evaporator is heated and a desired evaporation is performed, e.g. while substrates to be coated are continuously transported in front of the evaporation opening of the evaporator device 100. Since the shielding frame expands during heating of the crucible, a close fit between the shielding frame 120 and the cooling frame 110 is provided. Therefore, large areas of the shielding frame 120 are cooled. Further, the shielding frame 120 is fixed inside of the coating frame 110 during evaporation.
After coating of the substrates using the evaporator device according to embodiments disclosed herein, the heating of the crucible may be stopped. Hence, the crucible and the shielding frame cool down. The shielding frame 120 shrinks and is loosened from the cooling frame 110. Hence, an exchange of the shielding frame 120 may easily be performed, if necessary.
In one embodiment, a coating device may include an evaporation device according to any of the examples of embodiments described. For instance, the coating device may be a vacuum coating installation. In some examples of a coating device according to embodiments, a plurality of evaporator devices may be installed in an array or in line at a coating device, e.g. if large-area substrates have to be coated.
When using an evaporator device and performing a method of operating an evaporator device according to embodiments disclosed herein, the cooling is more effective as compared to an evaporator device or an operating method using a shielding mounted via a few screws at a distance to the cooling frame of the evaporator device. Moreover, during operation of the evaporator device the shielding frame may be fixed inside of the cooling frame. In addition, at non-operating temperatures, e.g. at ambient temperature, an easy and quick installation or exchange of the shielding frame is possible. Moreover, inexpensive shielding materials may be used, reducing the costs. Further, the structure of the evaporator device is simple and allows mounting and dismounting of the shielding frame without using installation tools or screws.
According to one embodiment, an evaporator device is provided, including a frame having an opening and being connectable to a cooling unit for cooling the frame, an evaporator being adapted for supporting an evaporation crucible within the frame, and a shielding frame, wherein the shielding frame is substantially concentrically within and adjacent to the frame detachably installable through the opening of the frame.
In some embodiments described herein, the shielding frame has a structure adapted for providing, when installed within the frame, a clearance to the frame at a non-operating temperature of the evaporator device and a close fit with the frame at an operating temperature of the evaporator device.
In some embodiments described herein, the shielding frame has a structure adapted for providing a clearance to the frame at a non-operating temperature of the evaporator crucible and a close fit with the frame at an operating temperature of the evaporator crucible.
In some embodiments described herein, the evaporator device has an evaporation side, the opening of the frame is provided at the evaporation side of the evaporator device,
In some embodiments described herein, the shielding frame has an opening and is installable within the frame such that the opening of the shielding frame is provided at the evaporation side of the evaporator device.
In some embodiments described herein, the evaporator is provided at an inner wall of the frame.
In some embodiments described herein, the shielding frame has at least one recess for receiving the evaporator.
In some embodiments described herein, the evaporator includes an electrical connector adapted for supplying heating current to an evaporator crucible supported on the evaporator.
In some embodiments described herein, the shielding frame and the frame have the same three-dimensional form and the shielding frame has a smaller volume than the frame.
In some embodiments described herein, the shielding frame and the frame are hollow cylinders.
In some embodiments described herein, the shielding frame and the frame are each tubular and/or the openings of the frame and of the shielding frame are tube openings.
In some embodiments described herein, the shielding frame and the frame have materials and dimensions adapted for providing, when the shielding frame is installed within the frame, a clearance between the shielding frame and the frame at an non-operating temperature of the evaporator device, and
In some embodiments described herein, the material of at least one of the shielding frame and the frame has a linear thermal expansion coefficient in the range of 5×10−6/K to 45×10−6/K at 20° C., or in the range of 10×10−6/K to 20×10−6/K at 20° C.,
In some embodiments described herein, the material of at least one of the shielding frame and the frame has a volumetric thermal expansion coefficient in the range of 10×10−6/K to 90×10−6/K at 20° C., or in the range of 30×10−6/K to 60×10−6/K at 20° C.
In some embodiments described herein, the material of at least one of the shielding frame and of the frame includes a metal.
In some embodiments described herein, the material of at least one of the shielding frame and the frame includes at least one element selected from the group consisting of a refractory metal, Iron and stainless steel.
According to another embodiment, a method of mounting an evaporator device is provided, including providing an evaporator device having a frame having an opening and being connectable to a cooling unit for cooling the frame, an evaporator being adapted for supporting an evaporation crucible within the frame, and a shielding frame, wherein the shielding frame is substantially concentrically within and adjacent to the frame detachably installable through the opening of the frame, arranging the shielding frame substantially concentrically within and adjacent to the frame, and optionally installing an evaporation crucible at the evaporator.
In some embodiments of a mounting method described herein, the shielding frame has a structure adapted for providing, when installed within the frame, a clearance to the frame at a non-operating temperature of the evaporator device and a close fit with the frame at an operating temperature of the evaporator device.
In some embodiments of a mounting method described herein, the shielding frame has a structure adapted for providing a clearance to the frame at a non-operating temperature of the evaporator crucible and a close fit with the frame at an operating temperature of the evaporator crucible.
According to a further embodiment, a method of operating an evaporator device is provided, including providing an evaporator device having a frame having an opening and being connectable to a cooling unit for cooling the frame, an evaporator being adapted for supporting an evaporator crucible within the frame, and a shielding frame, wherein the shielding frame is substantially concentrically within and adjacent to the frame detachably installable through the opening of the frame, the evaporator device having the shielding frame installed substantially concentrically within and adjacent to the frame, having an evaporator crucible provided at the evaporator, and optionally having the frame connected to the cooling unit, cooling the frame, and heating the evaporator crucible.
In some embodiments of an operating method described herein, the shielding frame has a structure adapted for providing, when installed within the frame, a clearance to the frame at a non-operating temperature of the evaporator device and a close fit with the frame at an operating temperature of the evaporator device.
In some embodiments of an operating method described herein, the shielding frame has a structure adapted for providing a clearance to the frame at a non-operating temperature of the evaporator crucible and a close fit with the frame at an operating temperature of the evaporator crucible.
According to a yet further embodiment, a coating device is provided, including an evaporator device having a frame having an opening and being connectable to a cooling unit for cooling the frame, an evaporator being adapted for supporting an evaporation crucible within the frame, and a shielding frame, wherein the shielding frame is substantially concentrically within and adjacent to the frame detachably installable through the opening of the frame, the evaporator device having the shielding frame installed substantially concentrically within and adjacent to the frame, having an evaporation crucible provided at the evaporator, and optionally having the frame connected to the cooling unit.
In some embodiments described herein, the coating device and/or the evaporator device are adapted for coating in vacuum.
In some embodiments of a coating device described herein, the shielding frame has a structure adapted for providing, when installed within the frame, a clearance to the frame at a non-operating temperature of the evaporator device and a close fit with the frame at an operating temperature of the evaporator device.
In some embodiments of a coating device described herein, the shielding frame has a structure adapted for providing a clearance to the frame at a non-operating temperature of the evaporator crucible and a close fit with the frame at an operating temperature of the evaporator crucible.
The written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modifications within the spirit and scope of the claims. Especially, mutually non-exclusive features of the embodiments described above may be combined with each other. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims.
While the foregoing is directed to embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
