Method for coating a coating area on the front surface of a substrate and apparatus for a thermal evaporation system

Abstract

The present invention relates to a method for coating a coating area (58) on a front surface (56) of a substrate (50) with a source material (40) that has been thermally evaporated and / or sublimated from a source (30) by electromagnetic radiation (80), and to an apparatus (100) for a thermal evaporation system (200) for coating a coating area (58) on a front surface (56) of a substrate (50) with a source material (40) that has been thermally evaporated and / or sublimated from a source (30) by electromagnetic radiation (80).

Description

[Technical Field]

[0001] The present invention relates to a method for coating a coating area on the front surface of a substrate with a source material that is thermally evaporated and / or sublimated from a source by electromagnetic radiation, wherein the source comprises one or more source parts made of the source material, the substrate and the source are placed in a reaction chamber containing a reaction atmosphere, and the electromagnetic radiation is provided as one or more incident radiation beams and coupled into the reaction chamber through a chamber window of the reaction chamber such that the one or more incident radiation beams and the perpendicular to the surface of the source make an incident angle greater than 0° and less than 90°, thereby forming a radiation plane. The present invention also relates to an apparatus for coating a coating area on the front surface of a substrate with a source material that has been thermally evaporated and / or sublimated from a source by electromagnetic radiation, the apparatus comprising a source arrangement for arranging a source having one or more source portions made of the source material, and a substrate arrangement for arranging a substrate, wherein the source arrangement and the substrate arrangement are arranged in a reaction chamber of the apparatus that can be filled with a reaction atmosphere, the reaction chamber further comprising a chamber window for coupling electromagnetic radiation provided as one or more incident radiation beams into the reaction chamber such that one or more incident radiation beams and a perpendicular to the surface of the source have an incident angle greater than 0° and less than 90°, thereby forming a radiation plane. [Background technology]

[0002] Figure 1 illustrates a simplified thermal evaporation system 200 based on the level of technology. The system 200 is based on sublimating and / or evaporating a source material 40 by bombarding it with electromagnetic radiation 80. In particular, in the thermal laser evaporation system 200, laser light 80 is used to evaporate and / or sublimate the source material 40 in order to coat a coating area 58 on a substrate 50. The source 30 and the substrate 50 are placed in a reaction chamber 10 of the apparatus 100, which may further be filled with a reaction atmosphere 14.

[0003] In such a system 200, a laser beam 80, or any electromagnetic radiation 80 generally suitable for evaporating and / or sublimating the source material 40, is coupled into the reaction chamber 10 through the chamber window 12 of the reaction chamber 10. In particular, in a system 200 of the art, a direct line of sight between the chamber window 12 and the source 30 is designed for the evaporation and / or sublimation of the source material 40 by the incident radiation beam 82.

[0004] However, as shown by the arrows in Figure 1 indicating the flow of evaporated and / or sublimated source material 40, the source material 40 is deposited not only on the coating area 58 of the substrate 50 but also on the chamber window 12. In other words, the chamber window 12 is exposed to the evaporated and / or sublimated flux, resulting in coating of the chamber window 12. In addition, there is spatial competition between the chamber window 12 and the substrate 50, especially when deposition on a large coating area 58 of the substrate is required. Either the laser beam 80 must collide with the source 30 at an angle that almost grazes it, causing the source surface 36 to deviate from a perfectly horizontal shape and resulting in unstable operation, or the substrate 50 must move far away from the source 30, requiring a very high local magnetic flux density on the source surface 36. Therefore, the combination of a large substrate 50 close to the source 30, which is ideal from the standpoint of material utilization, is difficult to achieve.

[0005] In view of the above, the object of the present invention is to provide an improved method for coating a coating area on the front surface of a substrate and an improved apparatus for coating a coating area on the front surface of a substrate, which do not have the drawbacks of the above-mentioned state of art. Specifically, the object of the present invention is to provide an improved method for coating a coating area on the front surface of a substrate and an improved apparatus for coating a coating area on the front surface of a substrate, which enable the protection of the chamber window from evaporated and / or sublimated source material without the need for a near-grazing collision of electromagnetic radiation onto the source, while simultaneously minimizing and / or optimizing the distance between the source surface and the coating area on the substrate. [Overview of the project]

[0006] This objective is satisfied by each of the independent patent claims. Specifically, this objective is satisfied by the method for coating a coating area on the front surface of a substrate as described in claim 1, and by the apparatus for coating a coating area on the front surface of a substrate as described in claim 30. Dependent claims describe preferred embodiments of the present invention. Details and advantages described with respect to the method for coating a coating area according to the first aspect of the present invention also refer to the apparatus for coating a coating area according to the second aspect of the present invention, in a technical sense, and vice versa.

[0007] According to a first aspect of the present invention, this objective is satisfied by a method for coating a coating area on the front surface of a substrate with a source material that is thermally evaporated and / or sublimated from a source by electromagnetic radiation, wherein the source comprises one or more source portions made of the source material, the substrate and the source are placed in a reaction chamber containing a reaction atmosphere, and the electromagnetic radiation is provided as one or more incident radiation beams and coupled into the reaction chamber through a chamber window of the reaction chamber such that the one or more incident radiation beams and perpendiculars to the surface of the source have an incident angle greater than 0° and less than 90°, thereby forming a radiation plane. The method according to the present invention is a) Providing a substrate using a substrate material that is transparent to or at least essentially transparent to electromagnetic radiation; b) A step of placing a substrate between the chamber window and the source in the reaction chamber, wherein the front surface of the substrate faces the source and the rear surface of the substrate faces the chamber window, c) A step of illuminating a source with one or more incident radiation beams through the substrate during the coating process, It is equipped with.

[0008] The methods according to the present invention are preferably intended to be carried out in and using a system for coating a coating area of ​​a substrate. The source material to be deposited is evaporated and / or sublimated by electromagnetic radiation striking the source material forming one or more source portions of the source. Each of the one or more source portions consists of a single source material. However, if there are two or more source portions in the source, the source materials of the different source portions may be the same or different.

[0009] The source and the substrate supporting the coating area are placed in a reaction chamber containing a reaction atmosphere. Preferably, the distance between the source and the coating area on the substrate is optimized to match the coating to be achieved. The reaction atmosphere according to the present invention is 10 -4 hPa~10 -12 For a vacuum of hPa and pure, ideal conditions, 10 -8 hPa~10 -12 It may be hPa, or 10 -8 The system may comprise or consist of one or more reaction gases, such as molecular oxygen, ozone, molecular hydrogen, or molecular nitrogen, each having an ambient pressure ranging from hPa to a maximum of 1 hPa. In the latter case, the reaction gases may preferably be selected according to the composition of the coating. Oxygen variants, O2 and O3, may preferably be provided in a ratio of approximately 9:1, as produced by an in-line glow discharge ozone generator. The reaction gases may also be at least ionized, and in particular by plasma ionization.

[0010] Electromagnetic radiation is supplied as one or more incident radiation beams and coupled into the reaction chamber through a chamber window. The electromagnetic radiation strikes the surface, forming an incident angle greater than 0° and less than 90°, along with a perpendicular to the source surface. Thus, a very small incident angle close to 0° represents an incident radiation beam striking the source surface almost perpendicularly, while a very large incident angle close to 90° represents an incident radiation beam that grazes the source surface.

[0011] According to the first step a) of the method according to the first aspect of the present invention, the substrate is provided using a substrate material that is transparent to or at least essentially transparent to electromagnetic radiation. In the sense of the present invention, transparent or at least substantially transparent specifically means that the transmitted electromagnetic radiation undergoes attenuation of less than 10%, preferably less than 1%. In other words, electromagnetic radiation can be irradiated through the substrate without significant attenuation. For this purpose, the substrate material is appropriately selected with respect to the electromagnetic radiation used, and in particular with respect to the wavelength of the electromagnetic radiation used.

[0012] Providing a substrate that is transparent to or at least essentially transparent to electromagnetic radiation enables the placement of the substrate between the chamber window and the source in the reaction chamber in the subsequent step b) of the method according to the first aspect of the present invention. Thus, during the coating process in step c) of the method according to the first aspect of the present invention, electromagnetic radiation enters the reaction chamber through the chamber window, strikes and irradiates the substrate, and only then strikes the target and illuminates the target.

[0013] In other words, the source surface is not masked by a substrate material that is transparent or at least essentially transparent with respect to electromagnetic radiation. Therefore, the positions of both the chamber window and the substrate can be selected without the constraint of needing a direct, unobstructed line of sight between the chamber window and the source surface.

[0014] The evaporation and / or sublimation flux of the source material, evaporated and / or sublimated by the colliding electromagnetic radiation, proceeds away from the surface of the source, particularly from a flat surface following a cosine distribution, for example. Therefore, in step b), the substrate is placed in the reaction chamber such that the front surface of the substrate supporting the coating area faces the source in order to enable the desired coating of the coating area.

[0015] However, as already mentioned with respect to Figure 1, the evaporated and / or sublimated source material does not only move toward the desired coating area. Nevertheless, the evaporated and / or sublimated source material generally moves along a straight line. In step b), the evaporated and / or sublimated source material is deposited on the substrate by positioning the substrate such that in step c), electromagnetic radiation is irradiated through the substrate during the illumination process of the source, and thus in the direct line of sight between the chamber window and the source. In particular, the deposition of evaporated and / or sublimated source material onto the chamber window can be prevented or at least significantly reduced. Since the deposition of evaporated and / or sublimated source material onto the chamber window has a significant impact on the service life of the entire evaporation system, the service life can be significantly extended. Preferably, the replacement of the chamber window due to coating by evaporated and / or sublimated source material can be completely avoided.

[0016] Preferably, a method according to a first aspect of the present invention may be characterized in that laser light, particularly having a wavelength of 10 nm to 100 μm, preferably a wavelength selected in the infrared region, and especially a laser light having a wavelength of 1 μm, is used as electromagnetic radiation. The laser light has the advantage of being coherent and being available over a wide range of wavelengths and intensities. Appropriate laser light can be selected for each specific source material to be evaporated and / or sublimated. The laser light can be provided in pulses or, more preferably, continuously. This can provide very homogeneous evaporation and / or sublimation, particularly below the plasma threshold of a particular source material.

[0017] In addition, a method according to a first aspect of the present invention may involve focusing one or more incident radiation beams toward a source such that the median intersection area between one or more incident radiation beams and the substrate is larger than the intersection area between one or more incident radiation beams and the surface of the source. In other words, the spatial energy density of electromagnetic radiation impacting the surface of the source is greater than the spatial energy density in and within the substrate. Even if the substrate is inherently transparent to electromagnetic radiation, a small portion of the energy of the radiation beams may be absorbed by the substrate. Reducing the spatial energy density further reduces the risk of the substrate being harmed by absorbed electromagnetic radiation. At the same time, providing a small intersection area between one or more incident radiation beams and the surface of the source ensures a high energy density at this location and, consequently, evaporation and / or sublimation of the source material.

[0018] In particular, the method according to the first aspect of the present invention can be improved by positioning the focal point or focal volume of one or more focused incident radiation beams on the surface of the source. Thus, the aforementioned spatial energy density of the impacting electromagnetic radiation is maximized at the surface of the target. As a result, the evaporation and / or sublimation process of the source material is improved. Within the scope of the present invention, a focal volume is the minimum volume per unit length along the propagation of electromagnetic radiation, and a focal point is a special and ideal case of a point-like focal volume.

[0019] Furthermore, the method according to the first aspect of the present invention may be characterized in that the coating region is arranged, at least on average, in a plane perpendicular to the radiation plane. As described above, the radiation plane is defined as including the incident radiation beam and the perpendicular to the surface of the source. In other words, a coating region perpendicular to the radiation plane ensures that, with respect to the surface of the source, the coating region is arranged in a plane symmetric with respect to the radiation plane. Therefore, the evaporated and / or sublimated source material reaches the coating regions on both sides of the radiation plane with the same spatial distribution and angular distribution. Thereby, a uniform deposition of the evaporated and / or sublimated source material onto the coating region can be achieved or at least improved.

[0020] In a further improvement, the method according to the first aspect of the present invention may comprise that at least the coating region of the substrate, in particular the entire substrate, is planar. In other words, the coating region is completely contained within the above-mentioned plane perpendicular to the radiation plane. Thereby, it may become easier to plan the deposition of the evaporated and / or sublimated source material onto the coating region. In addition, shadowing of a part of the coating region by other parts of the coating region of the entire substrate can be prevented. Furthermore, as will be described later, using a planar coating region or a planar substrate may more easily enable the movement of the substrate.

[0021] Also, the method according to the first aspect of the present invention may be characterized in that one or more incident radiation beams and the surface normal to the source form an incident angle of 20° to 70°, preferably 35° to 55°. The lower the incident angle, the lower the risk of unstable operation when the source surface deviates from a perfect horizontal shape. The higher the incident angle, the lower the probability of overlap between the intersection area of the incident radiation beam and the substrate, which may cause coating disturbance in the coating region, and the coating region. An incident angle of 20° to 70°, preferably 35° to 55°, provides a good compromise between these two constraints.

[0022] In addition, the method according to the first aspect of the present invention comprises that one or more incident radiation beams are reflected at the surface of one or more source portions and return as one or more reflected radiation beams, particularly back to the front surface of the substrate, and the one or more reflected radiation beams are included within the radiation plane. In other words, the incident electromagnetic radiation is coupled into the reaction chamber, irradiated through the substrate, impinges on the surface of the source for evaporation and / or sublimation of the source material, and is accordingly reflected at the surface of the source and returns onto the substrate, particularly onto the front surface of the substrate. Preferably, for some embodiments, the reflected radiation beam may impinge on the front surface of the substrate at a position at least partially coated with the evaporated and / or sublimated source material. This can be provided, for example, by arranging the substrate such that the reflected radiation beam hits the substrate at least partially in the coating area, but preferably by moving the substrate relative to the source during the coating process, as will be described later.

[0023] Since the electromagnetic radiation is specifically selected to evaporate and / or sublime the source material, the source material absorbs the electromagnetic radiation significantly better than, in most cases, a permeable or at least essentially permeable substrate. Thus, the coating on the front surface of the substrate is reheated by the reflected radiation beam, whereby an annealing process can be carried out. Thereby, the overall quality of the coating can be improved.

[0024] In an improved embodiment of the method according to the first aspect of the present invention, the substrate is inclined relative to the source at an inclination angle greater than 0° about an inclination axis perpendicular to the radiation plane, the inclination angle being made between the perpendicular to the center of the coating area and the line connecting the center of the surface of the source and the center of the coating area, and the inclination angle made is selected such that the distance between the intermediate intersection area of the one or more incident radiation beams and the substrate and the source is greater than the distance between the intermediate intersection area of the one or more reflected radiation beams and the substrate and the source.

[0025] As mentioned above, the incident radiation beam is focused toward the surface of the source. As a result, the reflected radiation beam also has its focal point or focal volume on the surface of the source, and spreads toward the front surface of the substrate as it propagates, moving away from the surface of the source.

[0026] Therefore, as a first approximation, the reflection of electromagnetic radiation on the source surface maintains the focal alignment of the incident radiation beam in the reflected radiation beam. Thus, in this embodiment, the intermediate intersection area between the incident radiation beam and the substrate is larger than the intermediate intersection area between the reflected radiation beam and the substrate. As described above, a larger intersection area results in a lower energy density for each radiation beam, and vice versa. Thereafter, the energy densities of the colliding radiation beam and the reflected radiation beam can be easily adjusted according to the requirements of the actual coating. In the embodiment described above, the energy density at the intersection area between the reflected beam and the substrate is increased by the inclination of the substrate. This may be advantageous, for example, when it is preferable to perform an annealing process, but a specific energy density of the reflected radiation beam is required, which can be achieved by reducing the distance between the source surface and the intersection area between the reflected radiation beam and the substrate.

[0027] According to an alternative embodiment, the method according to the first aspect of the present invention can be improved by the substrate being tilted with respect to the source at an angle greater than 0° about a tilt axis perpendicular to the radiation plane, wherein the tilt angle is made between a perpendicular to the center of the coating area and a line connecting the center of the surface of the source and the center of the coating area, and the tilt angle is selected such that the distance between the source and the intermediate intersection area between one or more incident radiation beams and the substrate is smaller than the distance between the source and the intermediate intersection area between one or more reflected radiation beams and the substrate.

[0028] In this alternative embodiment, the substrate tilt is provided in the opposite direction to that of the embodiments described above. However, all the details and advantages described with respect to the embodiments described above remain valid, except that the substrate tilt in the opposite direction is considered.

[0029] In particular, in this embodiment, the intermediate intersection area between the incident radiation beam and the substrate is smaller than the intermediate intersection area between the reflected radiation beam and the substrate. Here again, a smaller intersection area results in a higher energy density for each radiation beam, and vice versa. Thus, the energy densities of the colliding and reflected radiation beams can be easily adjusted according to the requirements of the actual coating. In this embodiment, the energy density at the intersection area between the reflected beam and the substrate is reduced by the inclination of the substrate. This can be advantageous, for example, if the energy density of the reflected beam is too high, for example, high enough to cause the evaporation and / or sublimation processes of the source material deposited on the coating area on the front surface of the substrate to occur again. This can thus avoid the adverse effects of the reflected radiation beam colliding with the source material deposited on the front surface of the substrate. However, the inclination angle can be selected so that the annealing process can still be carried out.

[0030] Preferably, the method according to the first aspect of the present invention can be further improved by selecting a substrate tilt angle to adjust the energy density of one or more reflected radiation beams at the front surface of the substrate. As described above, the energy density of the reflected radiation beam at the front surface of the substrate depends on the focal characteristics of the radiation beam, in particular, on the distance between the reflective surface of the source and the intersection area between the reflected radiation beam and the substrate. Therefore, the latter value can be easily changed by actively adjusting the tilt angle. This allows, on the one hand, general adjustment of the energy density based on a given focal characteristic of the radiation beam, and on the other hand, active control of the energy density based on changes in focal characteristics, particularly by closed-loop control.

[0031] As described above, the back reflection of the incident radiation beam onto the front surface of the substrate is advantageous for some coating processes that can be provided by the method according to the first aspect of the present invention. However, the reverse is also possible; that is, the reflected radiation beam will damage the coating on areas of the substrate that have already been coated.

[0032] In this case, the method according to the first aspect of the present invention can be improved by tilting the substrate with respect to the source at an angle greater than 0° about an inclination axis perpendicular to the radiation plane, wherein the inclination angle is made between a perpendicular to the center of the coating area and a line connecting the center of the source surface and the center of the coating area, and the inclination angle is selected such that one or more reflected radiation beams miss the front of the substrate. Using such a substrate arrangement, in particular by appropriately selected inclination angles of the substrate, collision of reflected radiation beams with the front can be prevented. This can avoid the damaging effect on the substrate coating caused by the reflected radiation beams.

[0033] Additionally or alternatively, the method according to the first aspect of the present invention may also be improved by arranging absorber elements between the surface of one or more source portions and the front surface of a substrate such that one or more reflected radiation beams collide with the absorber elements and are absorbed by the absorber elements.

[0034] In some embodiments, spatial constraints and / or characteristics of the substrate itself prevent the aforementioned tilt of the substrate away from the reflected radiation beam. In such cases, absorber elements appropriately positioned within the path of the reflected radiation beam may be used to absorb the reflected radiation beam and, consequently, to prevent the damaging effect on the substrate coating caused by the reflected radiation beam. However, absorber elements may also be used in addition to the aforementioned tilt of the substrate.

[0035] According to a particularly preferred embodiment of the method according to a first aspect of the present invention, the substrate is moved relative to the position of the coating area on the front surface of the substrate to reposition the substrate during the coating process, and the distance between the source and the coating area is kept constant or at least essentially constant. In other words, in this embodiment, continuous coating of a large area on the front surface of the substrate can be provided. By keeping the distance between the source and the coating area constant or at least essentially constant, continuous coating in a stationary state or at least essentially stationary state can be provided. Alternatively or additionally, the homogeneity of the coating can be improved as a result.

[0036] In combination with the above embodiment, which includes a reflected radiation beam that strikes already coated areas on the front surface of the substrate, these already coated areas are also moved. Thereafter, the above annealing process can be carried out continuously in new unannealed areas.

[0037] Furthermore, the method according to the first aspect of the present invention can be improved by moving the substrate by at least one of the following methods. ·linear • Circular ·Spiral ·meandering This list is not closed, and other methods of moving the substrate are also possible. By selecting the most appropriate method of moving the substrate, a wide variety of possible coating patterns can be provided.

[0038] In addition, a method according to a first aspect of the present invention may include the substrate being moved along the line of intersection of the substrate and the radiation plane, at least on average. In particular, in the case of a planar substrate, the substrate is moved linearly along the line of intersection, at least on average. The above embodiments comprising a reflected radiation beam, and in particular the advantageous effects provided by such a reflected radiation beam, such as performing the annealing process in an already coated area on the substrate, can thereby be more easily implemented.

[0039] In another embodiment of the method according to the first aspect of the present invention, the substrate is subdivided into two or more substrate segments, the two substrate segments being arranged in a contiguous manner and connected in particular by a substrate connector, and moved together during the coating process. This allows coating areas on two or more separate substrate segments to be subsequently coated in a single coating session, preferably without the need to open the reaction chamber in between. This can increase the operating capacity of the method according to the first aspect of the present invention.

[0040] Two or more substrate segments may be held available within the reaction chamber. Additionally or alternatively, a suitable airlock may also be provided on the chamber wall of the reaction chamber, for example, to provide a load-lock chamber and / or differential pumping that can be pumped separately to successively supply two or more substrate segments for the intended coating.

[0041] Furthermore, a method according to a first aspect of the present invention may, in step c), if the substrate connector is less permeable with respect to electromagnetic radiation than the substrate material of the adjacent substrate segment, increase the intensity of one or more incident radiation beams during illumination of the substrate connector by a portion of one or more incident radiation beams. As described above, the incident radiation beams have a specific size, described by the intersection area between one or more incident radiation beams and the substrate when irradiated through the substrate. In most applications of the method according to a first aspect of the present invention, this intersection area will be larger than the size of the substrate connector. Thus, if the substrate connector is less permeable than the substrate segment, the incident radiation beams impacting the source are partially shadowed by the substrate connector. This shadowing effect can be counteracted by increasing the intensity of one or more incident radiation beams in step c) of the method according to the present invention. This can provide smooth, continuous, and uniform evaporation and / or sublimation of the source material.

[0042] Alternatively or additionally, a method according to a first aspect of the present invention may, in step c), if the substrate connector is more transparent with respect to electromagnetic radiation than the substrate material of the adjacent substrate segment, then the intensity of one or more incident radiation beams may be reduced during illumination of the substrate connector by a portion of one or more incident radiation beams. In contrast to the embodiments described in the preceding paragraph, the substrate connector now has higher transparency to the incident radiation beams than the transparency of the adjacent substrate segment. Thus, the incident radiation beams striking the source are partially enhanced when the intersection area between the incident radiation beams and the substrate includes the substrate connector. This enhancement effect can be offset by reducing the intensity of one or more incident radiation beams, thereby providing smooth, continuous, and uniform evaporation and / or sublimation of the source material.

[0043] Furthermore, a method according to a first aspect of the present invention may include reducing the speed of movement of the substrate during illumination of the substrate connector by a portion of one or more incident radiation beams, if the substrate connector is less permeable with respect to electromagnetic radiation than the substrate material of the adjacent substrate segment. The aforementioned shadowing effect of the substrate connector can also be offset by reducing the speed of movement of the substrate, i.e., two or more substrate segments continuously connected by the substrate connector, instead of increasing the intensity of one or more incident radiation beams. This can provide smooth, continuous, and uniform evaporation and / or sublimation of the source material.

[0044] Alternatively or additionally, if the substrate connector is more transparent with respect to electromagnetic radiation than the substrate material of the adjacent substrate segment, the speed of movement of the substrate may be increased during illumination of the substrate connector by a portion of one or more incident radiation beams. In the opposite case to the embodiments described in the preceding paragraph, i.e., in the case of a substrate connector that is more transparent than the substrate material, the enhancing effect caused by a substrate connector that is more transparent to electromagnetic radiation than the substrate material can be offset in particular by increasing the speed of movement of the substrate, i.e., two or more substrate segments continuously connected by the substrate connector, instead of reducing the intensity of one or more incident radiation beams. This can provide smooth, continuous, and uniform evaporation and / or sublimation of the source material.

[0045] According to a further alternative embodiment, the method according to the first aspect of the present invention may include moving the substrate at a constant speed. Moving the substrate at a constant speed is mechanically simple and can be easily provided. This can reduce the complexity of the apparatus for carrying out the method according to the first aspect of the present invention.

[0046] In addition, the method according to the first aspect of the present invention may also be provided as a flexible foil supported by support elements, particularly cylindrical rollers, within a reaction chamber, the foil being moved from a supply roll to a product roll during the coating process, the supply roll and / or product roll preferably located outside the reaction chamber. In embodiments having at least one of the rolls outside the reaction chamber, preferably a suitable airlock is provided in the chamber wall of the reaction chamber.

[0047] In other words, the flexible foil provided as a substrate is unwound from a supply roll, moved through the coating area, and then wound up again onto a product roll. Support elements within the reaction chamber ensure that the flexible foil remains in its track, and in particular, the support elements may also include one or more devices for applying tension to the foil. In the coating area, the flexible foil may be provided straight and / or bent, according to the requirements of the actual coating process. Furthermore, cooling of the foil is possible, for example, by an actively cooled support element or a designated cooling element located near the foil, the cooling element preferably comprising a cooling surface positioned parallel to the foil.

[0048] In summary, the flexible foil used as a substrate in the method according to the present invention allows for a significant increase in the dimensions of the substrate, particularly along the direction of movement. In embodiments of the coating process provided by the present invention, where the supply roll and product roll are located outside the reaction chamber, even the replacement of an exhausted supply roll or a fully filled product roll is possible. With respect to substrate supply alone, an infinite number of coating processes may be provided.

[0049] Furthermore, a method according to a first aspect of the present invention may be characterized in that the source comprises two or more, particularly separate, source portions, each of which is made of source material. As described above, the spatial characteristics of evaporation and / or sublimation mainly follow a cosine distribution, especially for sources having a flat surface. By comprising two or more source portions, each of which is illuminated by one or more incident radiation beams, the evaporated and / or sublimated source materials of the two or more individual source portions can be combined, and therefore the deposition of the source material onto the coating region on the front surface of the substrate can be made more uniform, the deposition can be accelerated, and / or the size of the coating region can be increased, and / or the shape of the coating region can be changed. In particular, the spatial homogeneity of the deposition flux, which results in variations in the thickness of the deposited film, can be minimized.

[0050] According to a further embodiment of the method according to the first aspect of the present invention, two or more of the source materials in the source portion are different.

[0051] In addition, a method according to a first aspect of the present invention may also include a source shape such that one or more of the source segments have a source shape such that the portion of the source shape extending perpendicular to the radiation plane is larger than the portion of the source shape extending parallel to the radiation plane. In other words, since the source segments are illuminated, in particular fully illuminated, by the incident radiation beam, the spatial distribution of evaporated and / or sublimated source material in the source segments also has a larger range perpendicular to the radiation plane than parallel to the radiation plane. Thus, the advantages of changing the shape of the spatial distribution of evaporated and / or sublimated source material described above for sources having two or more source segments can be provided by a single source segment. Therefore, a larger range of coating area perpendicular to the radiation plane, and thus automatically perpendicular to the direction of substrate movement, and improved thickness uniformity can be provided, particularly for substrates moved during the coating process. Preferably, this leads to increased spatial uniformity of the deposited layer on the substrate.

[0052] Furthermore, a method according to a first aspect of the present invention may be characterized in that one or more incident radiation beams have a beam shape such that the portion of the beam shape extending perpendicular to the radiation plane is larger than the portion of the beam shape extending parallel to the radiation plane. In particular, when combined with a source having two or more appropriately arranged source portions and / or a single source portion having a source shape expanded perpendicular to the radiation plane, illumination of the entire source by the incident radiation beam can be more easily provided. In particular, one or more incident radiation beams may have beams having a portion extending perpendicular to the radiation plane so that the source material can be evaporated and / or sublimated for deposition over the entire width of the coating area. Preferably, this leads to increased spatial uniformity of the deposited layer on the substrate.

[0053] Additionally or alternatively, a method according to a first aspect of the present invention may involve one or more incident radiation beams having a beam shape such that the portion of the beam shape extending perpendicular to the radiation plane is smaller than the portion of the beam shape extending parallel to the radiation plane. In other words, in contrast to the embodiments described in the preceding paragraphs, only a small portion of the possible width of the coating area is covered by the intersection area of ​​one or more incident radiation beams having a beam shape with a small portion extending perpendicular to the radiation plane. In many applications, such as solar cells, the final device has inactive areas such as contact stripes. By providing incident radiation beams having the above-described beam shapes, and thereby reflected radiation beams as well, it is possible to localize the intersection area to these areas that are not used by the functional film deposited on the coating area.

[0054] According to another embodiment of the method according to the first aspect of the present invention, electromagnetic radiation is provided as two or more incident radiation beams, each of which illuminates the source through the substrate during the coating process. In particular, this makes it possible to provide electromagnetic radiation focused simultaneously on two or more foci or focal volumes in the source, each foci or focal volume being composed of one of the two or more incident radiation beams. In a single source portion, a larger area of ​​the surface of that single source portion can be used for evaporation and / or sublimation of the source material, which is particularly advantageous for source portions having an elongated shape. In addition, in a source comprising two or more source portions, one or more of the two or more incident radiation beams can be assigned to each of the two or more source portions. In particular, if the two or more source portions comprise different source materials, the incident radiation beams assigned to a particular source portion can be adaptively selected for each source material, for example, with respect to wavelength and / or intensity.

[0055] According to a second aspect of the present invention, the object can be satisfied by an apparatus for a thermal evaporation system for coating a coating region on the front surface of a substrate with a source material thermally evaporated and / or sublimated by electromagnetic radiation from a source. This apparatus comprises a source arrangement for arranging a source comprising one or more source parts made of the source material, and a substrate arrangement for arranging the substrate. The source arrangement and the substrate arrangement are arranged in a reaction chamber of the apparatus capable of filling a reaction atmosphere. The reaction chamber further comprises a chamber window for coupling electromagnetic radiation provided as one or more incident radiation beams into the reaction chamber such that one or more incident radiation beams and a perpendicular to the surface of the source form an incident angle greater than 0° and less than 90°, thereby forming a radiation plane. The apparatus according to the second aspect of the present invention is characterized in that the substrate arrangement comprises a substrate holder for arranging the substrate between the chamber window and the source.

[0056] The apparatus according to the second aspect of the present invention is intended for use as part of a thermal evaporation system for coating a coating region of a substrate. The source material to be deposited is thermally evaporated and / or sublimated by electromagnetic radiation impinging on the source material forming one or more source parts of the source. Other parts of the thermal evaporation system can be means for providing a reaction atmosphere, such as a radiation source for providing one or more incident radiation beams, and a vacuum pump and / or a supply system for reaction gas.

[0057] By means of the above, the source and the substrate can be arranged in a reaction chamber capable of filling a reaction atmosphere. The reaction atmosphere can be a vacuum of 10 -4 hPa to 10 -12 hPa, and for pure ideal conditions it can be 10 -8 hPa to 10 -12 hPa, or 10 -8The system may comprise or consist of one or more reaction gases, such as molecular oxygen, ozone, molecular hydrogen, or molecular nitrogen, each having an ambient pressure ranging from hPa to a maximum of 1 hPa. In the latter case, the reaction gases may preferably be selected according to the composition of the coating. Oxygen variants, O2 and O3, may preferably be provided in a ratio of approximately 9:1, as produced by an in-line glow discharge ozone generator. The reaction gases may also be at least ionized, and in particular by plasma ionization.

[0058] To arrange the source and the substrate supporting the coating area, the apparatus according to the second aspect of the present invention comprises appropriate means, namely a substrate arrangement and a source arrangement, respectively. Preferably, the distance between the source and the coating area on the substrate is optimized to match the coating to be achieved.

[0059] Electromagnetic radiation is provided by a radiation source as one or more incident radiation beams, particularly as laser beams. To couple one or more incident radiation beams into a reaction chamber, the reaction chamber comprises one or more chamber windows.

[0060] The incident radiation beam strikes the surface of the source, forming an incident angle greater than 0° and less than 90°, along with the perpendicular to the source surface. Therefore, a very small incident angle close to 0° represents an incident radiation beam striking the source almost perpendicularly, while a very large incident angle close to 90° represents an incident radiation beam that grazes the source.

[0061] According to the present invention, the substrate holder of the substrate arrangement places the substrate between the chamber window and the source, and therefore within the path of one or more incident radiation beams. Preferably, a transparent substrate is used to avoid masking of the source by the substrate.

[0062] By positioning the substrate within a direct line of sight between the chamber window and the source, evaporated and / or sublimated source material advancing toward the chamber window is deposited on the substrate. This can prevent or at least significantly reduce the deposition of evaporated and / or sublimated source material onto the chamber window. Since the deposition of evaporated and / or sublimated source material onto the chamber window has a significant impact on the service life of the entire evaporation system, the service life can be significantly extended. Preferably, the replacement of the chamber window due to coating by evaporated and / or sublimated source material can be completely prevented.

[0063] Preferably, the apparatus according to a second aspect of the present invention may be configured to perform the method according to the first aspect of the present invention. Thus, the apparatus according to a second aspect of the present invention provides all the advantages described above with respect to the method according to the first aspect of the present invention. [Brief explanation of the drawing]

[0064] The present invention will be described in detail below by means of embodiments and with reference to the drawings. The drawings show the following:

[0065] [Figure 1] This is a thermal evaporation system based on the level of technology. [Figure 2] This is a thermal evaporation system according to the present invention. [Figure 3] This is a perspective view of a first embodiment of the coating process according to the present invention. [Figure 4] Figure 3 is a side view of an embodiment of the coating process. [Figure 5] This is a side view of a second embodiment of the coating process according to the present invention. [Figure 6] This is a perspective view of a third embodiment of the coating process according to the present invention. [Figure 7] This is a perspective view of a fourth embodiment of the coating process according to the present invention. [Figure 8] This is a perspective view of a fifth embodiment of the coating process according to the present invention. [Figure 9] This is a perspective view of a sixth embodiment of the coating process according to the present invention. [Figure 10] This is a perspective view of a seventh embodiment of the coating process according to the present invention. [Figure 11] These are side views of the eighth and ninth embodiments of the coating process according to the present invention. [Figure 12] This is another embodiment of the thermal evaporation system according to the present invention. [Figure 13] This is a radial plane as defined in the present invention. [Modes for carrying out the invention]

[0066] Figure 2 shows a simplified thermal evaporation system 200 according to the present invention. Similar to the state-of-the-art system 200 illustrated in Figure 1, the system 200 according to the present invention is also based on sublimating and / or evaporating a source material 40 by bombarding a source 30 that provides the source material 40 with electromagnetic radiation 80. However, as will be described below, the system 200 according to the present invention has several differences from the state-of-the-art system 200, and is in particular preferably constructed to be used to carry out the method according to the present invention.

[0067] The thermal evaporation system 200 shown in Figure 2 comprises an apparatus 100, an electromagnetic radiation source 102, and means (not shown) for providing a reaction atmosphere 14. A source arrangement 16 comprising a source 30 and a substrate arrangement 18 comprising a substrate 50 are placed inside the reaction chamber 10 of the apparatus 100, and in addition, the reaction chamber is filled with the reaction atmosphere 14.

[0068] Reaction atmosphere 14 is 10 -4 hPa~10 -12 For a vacuum of hPa and pure, ideal conditions, 10 -8 hPa~10 -12 It may be hPa, or 10 -8The system may comprise or consist of one or more reaction gases, such as molecular oxygen, ozone, molecular hydrogen, or molecular nitrogen, having an ambient pressure of preferably 1 hPa from hPa. In the latter case, the reaction gases may be preferably selected according to the composition of the coating. Oxygen variants, O2 and O3, may be provided in a ratio of approximately 9:1, preferably produced by an in-line glow discharge ozone generator. The reaction gases may also be at least ionized, particularly by plasma ionization.

[0069] For example, to deposit a metal oxide on a substrate 50, oxygen and / or ozone may be selected as the reaction gas for the reaction atmosphere 14, and each metal may be provided as a source material 40 that is evaporated and / or sublimated during the coating process. Each oxide is formed by the reaction of the evaporated and / or sublimated metal with oxygen atoms provided by the reaction atmosphere 14.

[0070] The electromagnetic radiation 80 provided by the electromagnetic radiation source 102, preferably laser light 80, particularly having wavelengths of 10 nm to 100 μm, preferably selected in the infrared range, especially 1 μm, is coupled into the reaction chamber 10 through the chamber window 12 and used as an incident radiation beam 82 to evaporate and / or sublimate the source material 40 to coat a coating area 58 on the front surface 56 of the substrate 50 (see Figures 3 to 12). The electromagnetic radiation 80 is preferably focused toward the source 30 such that the focal volume 88 of the incident radiation beam 82 is located on or near the surface 36 of the source 30, as shown in Figure 2.

[0071] In addition, the perpendicular 32 between the incident radiation beam 82 and the surface 36 of the source 30 forms an incident angle 84 of 20° to 70°, preferably 35° to 55° (see Figures 4, 5, and 11). Furthermore, the perpendicular 32 and the incident radiation beam 82 form and define a radiation plane 110. In particular, Figure 2 shows a side view of the thermal evaporation system 200, and the cross section is formed by the radiation plane 110. A descriptive representation of the definition of the radiation plane 110 is illustrated in Figure 13.

[0072] Essential to the present invention, in both the method and the apparatus 100, the substrate 50 is positioned between the chamber window 12 and the source 40 in step b) of the method according to the present invention. In other words, the substrate 50 is positioned within the direct line of sight between the chamber window 12 and the source 40. To prevent masking of the source 40, the substrate material 52 is provided in step a) of the method according to the present invention to be transparent to, or at least essentially transparent to, electromagnetic radiation 80. Thus, during the coating process, electromagnetic radiation 80 irradiates through the substrate 50 before striking the surface 36 of the source 30, and thus illuminates the source 30 in step c) according to the present invention. As a result, the evaporated and / or sublimated source material 40, illustrated as arrow 40 in Figure 2, is deposited on the front surface 56 of the substrate 50 and cannot reach the chamber window 12. Since the deposition of evaporated and / or sublimated source material 40 on the chamber window 12 has a significant impact on the service life of the entire evaporation system 200, the service life can be significantly extended. Preferably, the replacement of the chamber window 12 due to coating by evaporated and / or sublimated source material 40 can be completely prevented.

[0073] In the embodiment shown in Figure 2, the substrate 50 comprises four substrate segments 70 arranged in a continuous manner and connected by substrate connectors 72. Each substrate segment 70, and therefore the entire substrate 50, is planar. Thus, the coating area 58 is also planar and can be positioned in a plane perpendicular to the radial plane 110.

[0074] Furthermore, the entire substrate 50 is moved along the movement direction 64 by the actuator 22 of the substrate holder 20. Since the substrate connectors 72 may be more or less permeable to the incoming electromagnetic radiation 80 compared to the substrate segments 70, the speed of movement of the substrate 50 along the movement direction 64 may be appropriately reduced or increased when each substrate connector 72 is illuminated by the electromagnetic radiation 80. This allows the energy deposition of the electromagnetic radiation 80 into the source 30, and consequently the evaporation and / or sublimation rate of the source material 40, to be kept constant over time. Alternatively, the intensity of the electromagnetic radiation 80 may be temporarily increased or decreased to keep the evaporation and / or sublimation rate of the source material 40 constant over time.

[0075] Alternatively, particularly in the case of a substrate 50 consisting of a single substrate segment 70, such as a flexible foil 66 (see Figure 12), a constant speed of movement of the substrate 50 along the movement direction 64 is also possible. Furthermore, different movement patterns, such as linear, circular, helical, or meandering movement patterns, are also possible. Preferably, the substrate 50 moves, at least on average, along the intersection line of the substrate 50 and the radial plane 110 (see Figure 13).

[0076] Several examples of coating processes are illustrated in Figures 3 to 12 below. All of these coating processes are carried out using the apparatus 100 according to the present invention and its respective thermal evaporation system 200, as illustrated in Figure 2. In Figures 3 to 10 below, only the essential elements for each coating process are shown, although all other necessary elements of the apparatus 100 are still present even if they are not shown.

[0077] Figures 3 and 4 show a first example of a coating process made possible by the method and / or apparatus according to the present invention, illustrated in a perspective view in Figure 3 and a side view in Figure 4. Therefore, both Figures 3 and 4 will be described together below.

[0078] Figures 3 and 4 illustrate the basic components for the coating process enabled by the present invention. An incident radiation beam 82 illuminates a source 30 comprising a source material 40. The perpendicular 32 between the incident radiation beam 82 and the center 34 of the surface 36 of the source 30 forms the aforementioned angle of incidence 84. The center 34 of the surface 36 of the source 30 should be understood as the center of the intersection area 92 between the incident radiation beam 82 and the surface 36 of the source 30.

[0079] Essential to the present invention is the arrangement of the substrate 50 providing the coating area 58 such that the incident radiation beam 82 strikes the rear surface 54 of the substrate 50 and then irradiates through the substrate 50. For this purpose, the substrate material 52 of the substrate 50 is transparent to the incident radiation beam 82, or at least essentially transparent. This positioning of the substrate 50 offers several advantages. In the embodiments illustrated in Figures 3 and 4, the substrate is arranged such that it is perpendicular to the radiation plane 110, and furthermore, such that the perpendicular 60 of the center of the coating area 58 is parallel, in particular, identical to, the line connecting the center 34 of the surface 36 of the source 30 and the center 62 of the coating area 58.

[0080] First, since the substrate 50 itself is transparent or at least inherently transparent, constraints on the spatial arrangement of the source 30, the substrate 50, and / or the incident radiation beam 82 can be avoided or at least significantly reduced.

[0081] The evaporated and / or sublimated source material 40 is then deposited on the substrate 50, primarily on the coating area 58 on the front surface 56 of the substrate 50, as desired. However, the evaporated and / or sublimated source material 40 also moves toward the chamber window 12 (see Figure 2) along the line of sight of the incident radiation beam 82. This source material 40 also deposits on the substrate 50, and thus the deposition of source material 40 onto the chamber window 12 can be prevented. This results in a significant extension of the service life of the entire thermal evaporation system 200 (see Figure 2).

[0082] In addition, the incident radiation beam 82 is focused toward the source 30. Preferably, as shown in Figures 3 and 4, the intersection area 92 between the incident radiation beam 82 and the source 30 is formed by or near the focal point or focal volume 88 of the incident radiation beam 82. As a result, the intermediate intersection area 94 between the incident radiation beam 82 and the substrate 50 covers a much larger area than the intersection area 92, and therefore, the energy deposition in the substrate 50 by the incident radiation beam 50 can be further reduced.

[0083] Furthermore, the incident radiation beam 82 can be reflected by the surface 36 of the source 30 to become a reflected radiation beam 86. The reflected radiation beam 86 is, by definition, contained within the radiation plane 110 and intersects with the substrate 50 again in the intersection area 96. In particular, in embodiments such as those shown in Figures 3 and 4, where the substrate 50 is moved along the direction of movement 64, the substrate 50 is already coated with at least the source material 40 in the region of the intersection area 96. Therefore, and in addition, due to the fact that in most cases the deposited material in the coated area 58 is less permeable than the substrate material 52, the energy deposited on the substrate 50 by the reflected radiation beam 86 and the already deposited source material 40 can carry out the annealing process.

[0084] Figures 5 through 12 below illustrate variations of the basic coating process shown in Figures 3 and 4. Therefore, with respect to the following embodiments, the differences from the coating process shown in Figures 3 and 4 will be explained in particular. For elements that remain unchanged, refer to the preceding explanation of Figures 3 and 4.

[0085] Figure 5 shows a second embodiment of the coating process enabled by the present invention. This embodiment is largely the same as, or at least similar to, the embodiments illustrated in Figures 3 and 4, except that the substrate is tilted at an angle 74 about a tilt axis 76. The angle 74 is made between a perpendicular 60 to the center 62 of the coating area 58 and a line connecting the center 34 of the surface 36 of the source 30 and the center 62 of the coating area 58.

[0086] As can be clearly seen in Figure 5, by tilting the substrate 50, the sizes of the intersection areas 94 and 96 of the incident radiation beam 82 and the reflected radiation beam 86 can be changed, while at the same time, the size of the coating area 58 is kept more or less constant.

[0087] In the embodiment shown in Figure 5, the intersection area 96 between the reflected radiation beam 86 and the substrate 50 is enlarged, thereby reducing the energy deposition within the substrate 50 caused by the reflected radiation beam 86, and in particular, the coating on the front surface 56 of the substrate 50 located in the intersection area 96. This may be applied, for example, to weaken or completely prevent the annealing process. In an alternative embodiment, the substrate 50 may also be tilted in the opposite direction, resulting in an increase in the respective energy deposition in the intersection area 96.

[0088] Figures 6 and 7 show embodiments of the coating process, in which the incident radiation beam 82 has a beam shape 90 such that the portion of the beam shape 90 extending perpendicular to the radiation plane 110 is larger than the portion of the beam shape 90 extending parallel to the radiation plane 110. The two embodiments shown differ in the source shape 42 of the source 30; in Figure 6, the source shape 42 is more or less circular, while in Figure 7, the source shape 42 is also enlarged perpendicular to the radiation plane 110.

[0089] In both embodiments, the incident radiation beam 82 is focused toward the source 20, and therefore at a focal point 88 on or near the source surface 36 in Figure 6, and at an elongated, linear focal volume 88 on or near the source surface 36 in Figure 7. Thus, in both embodiments, focused, high-power-density illumination of the entire source 30 can be provided.

[0090] In the embodiment shown in Figure 6, the beam shape 90 inevitably results in the intersection areas 94 and 96 with the substrate 50 covering a wider area perpendicular to the radiation plane compared to the respective intersection areas 94 and 96 resulting from a circular beam shape 90 having the same cross-sectional area. Therefore, the coverage of the coating area 58 can be improved, particularly by the intersection areas 96 of the reflected radiation beam 86.

[0091] In addition to the advantages mentioned above, when combined with a source 30 having a source shape 42 similarly extended perpendicular to the radiation plane 110 as shown in Figure 7, illumination of the entire source 30 by the incident radiation beam 82 can be ensured by the extended portion of the beam shape 90 perpendicular to the radiation plane 110. Thus, the incident radiation beam 82 can evaporate and / or sublimate the source material 40 from the source 30 for deposition across the entire width of the coating region 58.

[0092] Additionally or alternatively, in another possible embodiment shown in Figure 8, the incident radiation beam 82 has a beam shape 90 such that the portion of the beam shape 90 extending perpendicular to the radiation plane 110 is smaller than the portion of the beam shape 90 extending parallel to the radiation plane 110. In other words, only a small portion of the possible width of the coating region 58 is covered by the intersection areas 94,96 of the incident radiation beam 82 and the reflected radiation beam 86, respectively. In many applications, such as solar cells, the final device has inactive areas such as contact stripes. By providing the incident radiation beam 82 having the aforementioned beam shape 90, and thereby the reflected radiation beam 86, it is possible to localize the intersection areas 94,96 to these areas that are not used by the functional film deposited on the coating region 58.

[0093] Figure 9 shows a further embodiment of the coating process provided by the present invention. In contrast to the embodiments described above, two separate incident radiation beams 82 are used, both focused onto the same source 30. This allows for a reduction in the energy density of the intersection areas 94,96 of both the incident radiation beam 82 and the reflected radiation beam 86, respectively. For example, the need for large intersection areas 94,96 to deposit energy into the substrate 50 and / or diffuse the material deposited on the coating area 58 may conflict with limitations on the available solid angle within the reaction chamber 10. The use of two or more incident radiation beams 82 can provide a solution to these competing boundary conditions.

[0094] Both incident radiation beams 82 define their own radiation planes 110 (not explicitly referenced in Figure 9). Clearly visible, each radiation plane 110 in this geometry is rotated about a direction within the radiation plane 110 with respect to the transport direction 64 and generally with respect to the elongated shape of the substrate 50. If the value of this rotation angle is sufficiently high and / or the incident angle 84 of each incident radiation beam 82 (see Figure 13) is sufficiently low, the intersection area 96 of the reflected radiation beam 86 is moved outside the area of ​​the substrate 50, allowing the reflected radiation beam 86 to detach from the substrate and / or be absorbed not by the substrate 50 but by a separate fixed absorber element 24 (not shown) adjacent to the substrate 50, thereby avoiding or significantly reducing the interaction of the reflected radiation beam 86 with the front surface 56 of the substrate 50 and thereby with the source material 40 deposited on the coating area 58.

[0095] Similar results to those that can be provided using a source 30 having a linear source shape 42 as illustrated in Figure 7 can be provided using a source 30 having two or more particularly separate source sections 38, each made of source material 40, as shown in Figure 10. In Figure 10, each of the source sections 38 is illuminated by a separate incident radiation beam 82. However, a single incident radiation beam 82 having an expanded or divided range covering both source sections 38 is also possible. Such separate incident radiation beams 82 may also originate from a single electromagnetic radiation source 102 (see Figure 2) which is divided into several incident radiation beams 82 by a mirror, beam splitter, or similar optical device.

[0096] The evaporated and / or sublimated source material 40 from the two individual source portions 38 combine for coating the coating region 58. Therefore, if both source portions 38 contain the same source material 40, the deposition of the source material 40 onto the coating region 58 on the front surface 56 of the substrate 50 can be accelerated, and / or the size of the coating region 58 can be enlarged, and / or the shape of the coating region 58 can be changed. In particular, the uniformity of the deposition film thickness can be improved, especially in the direction perpendicular to the direction of movement 64 along the front surface 56 of the substrate.

[0097] Alternatively, the source material 40 of the source portion 38 may be different. As described above, the evaporated and / or sublimated source material 40 of the source portion 38 combine during the coating process and are deposited together on the coating region 58. Thus, by providing different source materials 40, these different materials 40 are deposited together on the coating region 58 on the front surface 56 of the substrate 50. This may provide a deposition of alloys and / or compounds comprising or composed of different source materials 40, which also include atoms of the reaction gas of the reaction atmosphere 14, if applicable.

[0098] In particular, the reaction of one or more different source materials 40 that have evaporated and / or sublimated may result in a change in the reaction product with respect to the permeability with respect to electromagnetic radiation 80. Preferably, this change is an increase in permeability, and as a result, the reaction product deposited on the substrate 50 becomes more permeable to electromagnetic radiation 80 than each of the source materials 40. In this way, the absorption of electromagnetic radiation 80 that has passed through the substrate 50 by the deposited film may be reduced, thereby reducing or even avoiding the need to move the substrate 50 so that a region of sufficient permeability of the substrate 50 is continuously available for electromagnetic radiation 80 that has passed through the substrate 50 and the deposited film.

[0099] As described above with respect to Figures 3 to 10, the incident radiation beam 82 can be reflected by the surface 36 of the source 30 and become a reflected radiation beam 86 that returns onto the front surface 56 of the substrate 50. However, in some embodiments of the coating process provided by the present invention, the collision of the reflected radiation beam 86 onto the already coated portion of the front surface 56 would be counterproductive. However, Figure 11 illustrates two possible solutions, labeled "A" and "B," provided by the present invention to prevent the back reflection of electromagnetic radiation 80 onto the front surface 56. Solution "A," shown in the upper half of Figure 11, is based on tilting the substrate 50 away from the reflected radiation beam 86 of the electromagnetic radiation 80 at an inclination angle 74 greater than 0° around an inclination axis 76 perpendicular to the radiation plane 110. Here again, the inclination angle 74 is made between the perpendicular 60 to the center 62 of the coating region 76 and the line connecting the center 34 of the surface 36 of the source 30 and the center 62 of the coating region 76. In particular, the inclination angle 74 is selected so that one or more reflected radiation beams 86 miss the front surface 56 of the substrate 50. This arrangement of the substrate 50 can prevent the reflected radiation beams 86 from hitting the front surface 56. This can prevent damage to the coating of the substrate 50 caused by the reflected radiation beams 86.

[0100] As illustrated as solution "B" in the lower half of Figure 11, a appropriately positioned absorber element 24 can also be used to absorb the reflected radiation beam 86 before it strikes the front surface 56 of the substrate 50. This absorber element 24 is positioned within the path of the reflected radiation beam 86 and therefore absorbs the reflected radiation beam 86. This can prevent damage to the coating of the substrate 50 caused by the reflected radiation beam 86.

[0101] The solutions described in the preceding paragraph are particularly suitable for embodiments of the method according to the present invention in which spatial constraints and / or features of the substrate 50 itself prevent the aforementioned tilt of the substrate 50 away from the reflected radiation beam 86. However, the absorber element 24 may also be used in addition to the aforementioned tilt of the substrate 50.

[0102] Figure 12 illustrates another possible embodiment of the evaporation system 200 according to the present invention. This embodiment shares some features with the embodiment shown in Figure 2, the corresponding above description of which is referenced hereby. Specifically, the system 200 of Figure 12 also comprises an apparatus 100, an electromagnetic radiation source 102, and a reaction chamber 10 filled with a reaction atmosphere 14. A source arrangement 16, comprising a source 30, is additionally located within the reaction chamber 10 of the apparatus 100, which is filled with the reaction atmosphere 14.

[0103] Here too, the electromagnetic radiation 80, preferably laser light 80, provided by the electromagnetic radiation source 102 is coupled into the reaction chamber 10 through the chamber window 12 and used as an incident radiation beam 82 to evaporate and / or sublimate the source material 40 to coat the coating area 58 on the front surface 56 of the substrate 50. The electromagnetic radiation 80 is focused toward the source 30.

[0104] The main difference is that in system 200 of Figure 12, the substrate 50 is provided as a flexible foil 66. The foil 66 is supplied by a supply roll 202 and moved through the reaction chamber 10 by an actuator 22 of the substrate holder 20, where it is coated in the coating area 58 along the way, and then wound onto a product roll 204. Providing the flexible foil 66 as the substrate 50 allows for a significant increase in the dimensions of the substrate 50, particularly along the direction of movement 64.

[0105] A support element 26, preferably a cylindrical roller as shown, within the reaction chamber 10 supports and guides the foil 66. In the illustrated embodiment, the supply roll 202 is located outside the reaction chamber 10, and the product roll 204 is located inside the reaction chamber 10. In other embodiments, this arrangement scheme may be switched, or both rolls 202 and 204 may be located inside or outside the reaction chamber 10, respectively. In an embodiment having at least one of the rolls 202 and 204 outside the reaction chamber 10, as illustrated in Figure 12, a suitable airlock 29 is provided in the chamber wall of the reaction chamber 10.

[0106] As shown in the figure, the flexible foil 66 may be provided straight in the coating area 58. Alternatively, a bent arrangement of the foil 66 in the coating area 58 is also possible. Furthermore, cooling of the foil 66 may also be provided, for example, by actively cooled support elements 26, 28, or by a designated cooling element 28 located near the foil 66, preferably having a cooling surface parallel to the foil 66.

[0107] In the illustrated embodiment, the substrate 50, i.e., the foil 66, moves around the support element 26 immediately after leaving the coating area 58. Thus, the foil 66 is bent away from the reflected radiation beam 86 so as not to come into contact with it. This produces the same effect as described with respect to embodiment "A" of Figure 11, which is provided by a suitable inclination of the planar substrate 50.

[0108] Additionally, an extra absorber element 24 is also part of the embodiment of the system 200 shown in Figure 12. This further ensures that the reflected radiation beam 82 returning to the front surface 56 does not collide.

[0109] Figure 13 schematically shows the definition of the radiation plane 110, which was referenced in the preceding explanations of Figures 2 to 12. The perpendicular 32 of the surface 36 of the source 30 and the incident radiation beam 82 make an incident angle of 84. Therefore, this perpendicular 32 and the incident radiation beam 82 span a plane, specifically the radiation plane 110. In Figure 13, the radiation plane 110 and the projection plane are identical. [Explanation of Symbols]

[0110] 10 Reaction Chamber 12 Chamber window 14 Reaction atmosphere 16 Sauce Arrangements 18 Circuit board arrangements 20 PCB holders 22 Actuators 24 Absorber elements 26 Support elements 28 Cooling elements 29 Airlock 30 Sources 32 Perpendicular line (source) 34. Center (Source) 36 Surface 38. Source section 40 Sauce Ingredients 42 Source Shape 50 circuit boards 52 Substrate Materials 54 Rear 56 Front 58 Coating area 60 Perpendicular line (coating area) 62 Center (Coating Area) 64 Direction of movement 66 foil 70 substrate segments 72 PCB connectors 74 Tilt angle 76 Tilt axis 80 Electromagnetic radiation 82 Incident radiation beam 84 Entrance bevel angle 86 Reflected radiation beam 88 Focal points / Focal volume 90 Beam shape 92. Intersection Area (Induction beam and source) 94. Intersection area (incident radiation beam and substrate) 96. Intersection area (reflected beam and substrate) 100 devices 102 Electromagnetic radiation sources 110 Radial plane 200 Systems 202 Supply Roll 204 Product Rolls

Claims

1. A method for coating a coating area (58) on the front surface (56) of a substrate (50) with a source material (40) that has been thermally evaporated and / or sublimated from a source (30) by electromagnetic radiation (80), The source (30) comprises one or more source sections (38) made of the source material (40), The substrate (50) and the source (30) are placed in a reaction chamber (10) containing a reaction atmosphere (14). The electromagnetic radiation (80) is provided as one or more incident radiation beams (82) and coupled into the reaction chamber (10) through the chamber window (12) of the reaction chamber (10) such that the one or more incident radiation beams (82) and the perpendicular (32) of the source (30) to the surface (36) make an incident angle (84) greater than 0° and less than 90°, thereby forming a radiation plane (110). The aforementioned method, a) Providing the substrate (50) using a substrate material (52) that is transparent to or at least essentially transparent to the electromagnetic radiation (80), b) A step of placing the substrate (50) between the chamber window (12) and the source (30) in the reaction chamber (10), wherein the front surface (56) of the substrate (50) faces the source (30) and the rear surface (54) of the substrate (50) faces the chamber window (12), c) The coating process includes the step of illuminating the source (30) with one or more incident radiation beams (82) through the substrate (50), The one or more incident radiation beams (82) are reflected by the surface (36) of the one or more source portions (38) and return as one or more reflected radiation beams (86), and the one or more reflected radiation beams (86) are contained within the radiation plane (110). The substrate (50) is tilted with respect to the source (30) at an inclination angle (74) greater than 0°, with respect to an inclination axis (76) perpendicular to the radial plane (110). The inclination angle (74) is made between the perpendicular (60) to the center (62) of the coating region (58) and the line connecting the center (34) of the surface (36) of the source (30) and the center (62) of the coating region (58). The method is characterized in that the inclination angle (74) is selected such that the distance between the intermediate intersection area (94) between the one or more incident radiation beams (82) and the substrate (50) and the source (30) is greater than the distance between the intermediate intersection area (96) between the one or more reflected radiation beams (86) and the substrate (50) and the source (30).

2. A method for coating a coating area (58) on the front surface (56) of a substrate (50) with a source material (40) that has been thermally evaporated and / or sublimated from a source (30) by electromagnetic radiation (80), The source (30) comprises one or more source sections (38) made of the source material (40), The substrate (50) and the source (30) are placed in a reaction chamber (10) containing a reaction atmosphere (14). The electromagnetic radiation (80) is provided as one or more incident radiation beams (82) and coupled into the reaction chamber (10) through the chamber window (12) of the reaction chamber (10) such that the one or more incident radiation beams (82) and the perpendicular (32) of the source (30) to the surface (36) make an incident angle (84) greater than 0° and less than 90°, thereby forming a radiation plane (110). The aforementioned method, a) Providing the substrate (50) using a substrate material (52) that is transparent to or at least essentially transparent to the electromagnetic radiation (80), b) A step of placing the substrate (50) between the chamber window (12) and the source (30) in the reaction chamber (10), wherein the front surface (56) of the substrate (50) faces the source (30) and the rear surface (54) of the substrate (50) faces the chamber window (12), c) The coating process includes the step of illuminating the source (30) with one or more incident radiation beams (82) through the substrate (50), The one or more incident radiation beams (82) are reflected by the surface (36) of the one or more source portions (38) and return as one or more reflected radiation beams (86), and the one or more reflected radiation beams (86) are contained within the radiation plane (110). The substrate (50) is tilted with respect to the source (30) at an inclination angle (74) greater than 0°, with respect to an inclination axis (76) perpendicular to the radial plane (110). The inclination angle (74) is made between the perpendicular (60) to the center (62) of the coating region (58) and the line connecting the center (34) of the surface (36) of the source (30) and the center (62) of the coating region (58). The method is characterized in that the inclination angle (74) is selected such that the distance between the intermediate intersection area (94) between the one or more incident radiation beams (82) and the substrate (50) and the source (30) is smaller than the distance between the intermediate intersection area (96) between the one or more reflected radiation beams (86) and the substrate (50) and the source (30).

3. The method according to claim 1 or 2, characterized in that the inclination angle (74) of the substrate (50) is selected to adjust the energy density of one or more reflected radiation beams (86) on the front surface (56) of the substrate (50).

4. A method for coating a coating area (58) on the front surface (56) of a substrate (50) with a source material (40) that has been thermally evaporated and / or sublimated from a source (30) by electromagnetic radiation (80), The source (30) comprises one or more source sections (38) made of the source material (40), The substrate (50) and the source (30) are placed in a reaction chamber (10) containing a reaction atmosphere (14). The electromagnetic radiation (80) is provided as one or more incident radiation beams (82) and coupled into the reaction chamber (10) through the chamber window (12) of the reaction chamber (10) such that the one or more incident radiation beams (82) and the perpendicular (32) of the source (30) to the surface (36) make an incident angle (84) greater than 0° and less than 90°, thereby forming a radiation plane (110). The aforementioned method, a) Providing the substrate (50) using a substrate material (52) that is transparent to or at least essentially transparent to the electromagnetic radiation (80), b) A step of placing the substrate (50) between the chamber window (12) and the source (30) in the reaction chamber (10), wherein the front surface (56) of the substrate (50) faces the source (30) and the rear surface (54) of the substrate (50) faces the chamber window (12), c) The coating process includes the step of illuminating the source (30) with one or more incident radiation beams (82) through the substrate (50), The one or more incident radiation beams (82) are reflected by the surface (36) of the one or more source portions (38) and return as one or more reflected radiation beams (86), and the one or more reflected radiation beams (86) are contained within the radiation plane (110). The substrate (50) is tilted with respect to the source (30) at an inclination angle (74) greater than 0°, with respect to an inclination axis (76) perpendicular to the radiation plane (110). The inclination angle (74) is made between the perpendicular (60) of the center (62) of the coating region (58) and the line connecting the center (34) of the surface (36) of the source (30) and the center (62) of the coating region (58). A method characterized in that the inclination angle (74) is selected such that one or more reflected radiation beams (86) do not pass over the front surface (56) of the substrate (50).

5. The method according to claim 4, characterized in that the absorber element (24) is positioned between the surface (36) of the one or more source portions (38) and the front surface (56) of the substrate (50) such that one or more reflected radiation beams (86) collide with the absorber element (24) and are absorbed by the absorber element (24).

6. The method according to claim 1, characterized in that the laser light is used as electromagnetic radiation (80).

7. The method according to any one of claims 1 to 6, characterized in that the one or more incident radiation beams (82) are focused toward the source (30) such that the intermediate intersection area (94) between the one or more incident radiation beams (82) and the substrate (50) is larger than the intersection area (92) between the one or more incident radiation beams (82) and the surface (36) of the source (30).

8. The method according to claim 7, characterized in that the focal point (88) or focal volume (88) of one or more focused incident radiation beams (82) is located on the surface (36) of the source (30).

9. The method according to any one of claims 1 to 8, characterized in that the coating region (58) is arranged in a plane perpendicular to the radial plane (110) on an average basis.

10. The method according to claim 9, characterized in that at least the coating region (58) of the substrate (50) is planar.

11. The method according to any one of claims 1 to 10, characterized in that the one or more incident radiation beams (82) and the perpendicular (32) to the surface (36) with respect to the source (30) form an incident angle (84) of 20° to 70°.

12. The substrate (50) is moved relative to the position of the coating area (58) on the front surface (56) of the substrate (50) in order to reposition the substrate (50) during the coating process. The method according to any one of claims 1 to 11, characterized in that the distance between the source (30) and the coating region (58) is kept constant or at least essentially constant.

13. The method according to claim 12, characterized in that the substrate (50) is moved in at least one of the following directions: linear, circular, spiral, or meandering.

14. The method according to claim 12 or 13, characterized in that the substrate (50) is moved, at least on average, along the line of intersection between the substrate (50) and the radial plane (110).

15. The substrate (50) is subdivided into two or more substrate segments (70), The method according to any one of claims 12 to 14, characterized in that the two substrate segments (70) are arranged in a continuous manner, connected by a substrate connector (72), and moved together during the coating process.

16. The method according to claim 15, characterized in that, in step c), if the substrate connector (72) is less permeable to electromagnetic radiation (80) than the substrate material (52) of the adjacent substrate segment (70), the intensity of one or more incident radiation beams (82) is increased during illumination of the substrate connector (72) by a portion of the one or more incident radiation beams (82).

17. The method according to claim 15 or 16, characterized in that, in step c), if the substrate connector (72) is more transparent with respect to the electromagnetic radiation (80) than the substrate material (52) of the adjacent substrate segment (70), the intensity of one or more incident radiation beams (82) is reduced when the substrate connector (72) is illuminated by a portion of the one or more incident radiation beams (82).

18. The method according to any one of claims 15 to 17, characterized in that, if the substrate connector (72) is less permeable to electromagnetic radiation (80) than the substrate material (52) of the adjacent substrate segment (70), the speed of the movement of the substrate (50) is reduced when the substrate connector (72) is illuminated by a portion of one or more incident radiation beams (82).

19. The method according to any one of claims 15 to 18, characterized in that, if the substrate connector (72) is more transparent with respect to the electromagnetic radiation (80) than the substrate material (52) of the adjacent substrate segment (70), the speed of the movement of the substrate (50) is increased during illumination of the substrate connector (72) by a portion of the one or more incident radiation beams (82).

20. The method according to any one of claims 12 to 17, characterized in that the substrate (50) is moved at a constant speed.

21. The method according to any one of claims 1 to 20, characterized in that the substrate (50) is provided as a flexible foil (66) supported by a support element (26) within the reaction chamber (10).

22. The source (30) comprises two or more source sections (38), The method according to any one of claims 1 to 21, characterized in that each of the source portions (38) is made of the source material (40).

23. The method according to claim 22, characterized in that two or more of the source materials (40) in the source portion (38) are different.

24. The method according to any one of claims 1 to 23, characterized in that one or more of the source portions (38) have a source shape (42) such that the portion of the source shape (42) that extends perpendicular to the radial plane (110) is larger than the portion of the source shape (42) that extends parallel to the radial plane (110).

25. The method according to any one of claims 1 to 24, characterized in that the one or more incident radiation beams (82) have a beam shape (90) such that the portion of the beam shape (90) that extends perpendicular to the radiation plane (110) is larger than the portion of the beam shape (90) that extends parallel to the radiation plane (110).

26. The method according to any one of claims 1 to 25, characterized in that the one or more incident radiation beams (82) have a beam shape (90) such that the portion of the beam shape (90) that extends perpendicular to the radiation plane (110) is smaller than the portion of the beam shape (90) that extends parallel to the radiation plane (110).

27. The electromagnetic radiation (80) is provided as two or more incident radiation beams (82), The method according to any one of claims 1 to 26, characterized in that each of the two or more incident radiation beams (82) illuminates the source (30) through the substrate (50) during the coating process.

28. A method for coating a coating area (58) on the front surface (56) of a substrate (50) with a source material (40) that has been thermally evaporated and / or sublimated from a source (30) by electromagnetic radiation (80), The source (30) comprises one or more source sections (38) made of the source material (40), The substrate (50) and the source (30) are placed in a reaction chamber (10) containing a reaction atmosphere (14). The electromagnetic radiation (80) is provided as one or more incident radiation beams (82) and coupled into the reaction chamber (10) through the chamber window (12) of the reaction chamber (10) such that the one or more incident radiation beams (82) and the perpendicular (32) of the source (30) to the surface (36) make an incident angle (84) greater than 0° and less than 90°, thereby forming a radiation plane (110). The aforementioned method, a) Providing the substrate (50) using a substrate material (52) that is transparent to or at least essentially transparent to the electromagnetic radiation (80), b) A step of placing the substrate (50) between the chamber window (12) and the source (30) in the reaction chamber (10), wherein the front surface (56) of the substrate (50) faces the source (30) and the rear surface (54) of the substrate (50) faces the chamber window (12), c) The coating process includes the step of illuminating the source (30) with one or more incident radiation beams (82) through the substrate (50), A method characterized in that one or more incident radiation beams (82) have a beam shape (90) such that the portion of the beam shape (90) that extends perpendicular to the radiation plane (110) is larger than the portion of the beam shape (90) that extends parallel to the radiation plane (110).

29. A method for coating a coating area (58) on the front surface (56) of a substrate (50) with a source material (40) that has been thermally evaporated and / or sublimated from a source (30) by electromagnetic radiation (80), The source (30) comprises one or more source sections (38) made of the source material (40), The substrate (50) and the source (30) are placed in a reaction chamber (10) containing a reaction atmosphere (14). The electromagnetic radiation (80) is provided as one or more incident radiation beams (82) and coupled into the reaction chamber (10) through the chamber window (12) of the reaction chamber (10) such that the one or more incident radiation beams (82) and the perpendicular (32) of the source (30) to the surface (36) make an incident angle (84) greater than 0° and less than 90°, thereby forming a radiation plane (110). The aforementioned method, a) Providing the substrate (50) using a substrate material (52) that is transparent to or at least essentially transparent to the electromagnetic radiation (80), b) A step of placing the substrate (50) between the chamber window (12) and the source (30) in the reaction chamber (10), wherein the front surface (56) of the substrate (50) faces the source (30) and the rear surface (54) of the substrate (50) faces the chamber window (12), c) The coating process includes the step of illuminating the source (30) with one or more incident radiation beams (82) through the substrate (50), A method characterized in that one or more incident radiation beams (82) have a beam shape (90) such that the portion of the beam shape (90) that extends perpendicular to the radiation plane (110) is smaller than the portion of the beam shape (90) that extends parallel to the radiation plane (110).

30. Apparatus (100) for a thermal evaporation system (200) that coats a coating area (58) on the front surface (56) of a substrate (50) with a source material (40) that has been thermally evaporated and / or sublimated from a source (30) by electromagnetic radiation (80), A source arrangement (16) for arranging the source (30) which comprises one or more source sections (38) made of the source material (40), The system includes a substrate arrangement (18) for arranging the substrate (50), The source arrangement (16) and the substrate arrangement (18) are placed in the reaction chamber (10) of the apparatus (100) which can be filled with the reaction atmosphere (14). The reaction chamber (10) further comprises a chamber window (12) for coupling the electromagnetic radiation (80) provided as one or more incident radiation beams (82) into the reaction chamber (10) such that one or more incident radiation beams (82) and the perpendicular (32) of the source (30) to the surface (36) have an incident angle (84) greater than 0° and less than 90°, thereby forming a radiation plane (110). The substrate arrangement (18) includes a substrate holder (20) for positioning the substrate (50) between the chamber window (12) and the source (30), The apparatus (100) is configured to perform the method described in any one of claims 1 to 29.

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