Coating device and method for operating a coating device

Abstract

The invention relates to a coating device and to a method for operating a coating device. According to different embodiments, a coating device (100) can have: a bearing device (130) which provides a rotational axis (131) and is designed to rotate a tubular sputtering target (10) supported by means of the bearing device (130) about the rotational axis (131); a plurality of movably supported coupling electrodes (110) which are arranged one behind the other in a row along the rotational axis (131) for coupling an alternating voltage into the sputtering target (10); and a positioning device (120) which is designed to influence a position of the plurality of coupling electrodes (110) relative to one another and / or relative to the rotational axis (131) on the basis of a parameter that represents a geometry of the sputtering target (10).

Description

[0001] Coating device and a method for operating a coating device

[0002] Various embodiments relate to a coating device and a method for operating a coating device.

[0003] In general, workpieces or substrates can be processed, e.g. machined, coated, heated, etched and / or structurally modified. One method for coating a substrate is cathode sputtering (so-called sputtering). By means of sputtering (i.e. by means of a sputtering process), one or more layers can be deposited on a substrate. For this purpose, a plasma-forming gas can be ionized using a cathode, whereby a material to be deposited (the so-called target material) of the cathode can be sputtered using the plasma thus formed. The sputtered target material can then be brought to a substrate on which it can be deposited and form a layer. The target material can be provided as a replaceable component, the so-called target.

[0004] Modifications of cathode sputtering include sputtering using a magnetron (a sputtering device comprising a magnet system), so-called magnetron sputtering, or so-called reactive magnetron sputtering. In these cases, the formation of the plasma can be assisted by a magnetic field. To generate the magnetic field, a magnet system can be arranged near the cathode (then also referred to as the magnetron cathode), which forms a self-contained magnetic field line tunnel (also referred to as a plasma channel or race track) on the surface of the target material (target surface). Plasma formation is promoted within this field line tunnel, allowing the formation of a toroidal plasma tube.

[0005] Modifications to cathode sputtering also include so-called AC sputtering, which is used, among other things, with a target material with low electrical conductivity. Instead of a direct current, where the target serves as the cathode, an alternating current (AC) is coupled into the target material to form the plasma, whereby the name "cathode" is often retained. In high-frequency sputtering (also known as HF sputtering or RF sputtering), the alternating current is a high-frequency alternating current. Due to various technological hurdles, RF sputtering is traditionally limited to planar, e.g., plate-shaped, targets, so-called planar cathodes.

[0006] Against this background, it has been recognized from various perspectives that RF sputtering cannot be readily transferred to tubular targets, so-called tubular cathodes. In particular, it has been recognized that the tubular target tends to be sputtered in an uneven manner during RF sputtering (also referred to as inhomogeneity). This inhomogeneous sputtering of the target material impairs both the resulting coating properties and the technical utilization of the tubular cathode (also referred to as target utilization). The latter is particularly important when the target material is very expensive, as in the case of indium tin oxide (ITO). Annual ITO target costs are in the millions of euros for highly productive production plants. Thus, simply increasing target utilization by 10% can save hundreds of thousands of euros per year.For example, the desired target utilization may be more than 80%, but this is rarely achieved. In many cases, target utilization is only 70% or less.

[0007] In this context, it was further recognized that the tendency towards inhomogeneous sputtering increases with the length of the tubular cathode, especially for lengths exceeding 1 m. Against this background, it was recognized that the propagation of electromagnetic waves in the target, which is conventionally excited by coupling the alternating voltage to the front of the target, leads to an inhomogeneous power distribution, which promotes the inhomogeneous sputtering of the target material. The propagation of the electromagnetic waves is clearly influenced by the elongated geometry of the tubular target in such a way that the resulting power distribution is modulated along the target length. This is the case, for example, when the alternating voltage is fed into the tubular cathode via so-called end blocks, as is conventionally the case.

[0008] According to various aspects, a coating device is provided that reduces the tendency for inhomogeneous sputtering of the target material, thus facilitating the sputtering of a target by means of an AC voltage coupled therein, especially when its length exceeds 1 m. This contributes to increasing target utilization and facilitates scaling sputtering to larger substrates, which in turn reduces operating costs or at least increases economic efficiency.

[0009] It was clearly recognized that the tendency towards inhomogeneous sputtering of the target material can be reduced by coupling the alternating voltage at several (e.g., more than two) points along the length of the target using electrodes (also referred to as coupling electrodes), so that the influence of the geometry of the tubular target on wave propagation is reduced. This makes it possible, for example, to adapt the number and / or spatial distribution of the coupling electrodes to the geometry of the tubular target. If the coupling electrodes are arranged outside the tubular target, this inhibits the interaction of the coupling electrodes with any processes or components present within the tubular target, which, for example, facilitates the cooling of the tubular target using a fluid arranged therein (e.g., a cooling liquid).If the position of the coupling electrodes depends on the geometry of the tube target, this promotes a uniform coupling of the alternating voltage into the tube target.

[0010] It shows

[0011] Figures 1A to 3A each show various aspects of a coating device according to various embodiments in a schematic view; Figures 3B and 3C each show various aspects of the circuit according to various embodiments in a schematic view;

[0012] Figure 3D shows various aspects of the coating device 100 according to various embodiments in a perspective schematic view;

[0013] Figure 4 shows various aspects of the coating device according to various embodiments in a schematic view; and

[0014] Figure 5 shows a method for operating a coating device in a schematic flow diagram.

[0015] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology such as "top," "bottom," "front," "back," "fore," "rear," etc., will be used with reference to the orientation of the described figure(s). Since components of embodiments can be positioned in a number of different orientations, the directional terminology is for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention.It is understood that the features of the various exemplary embodiments described herein may be combined with one another unless specifically stated otherwise. The following detailed description is therefore not to be construed in a limiting sense, and the scope of the present invention is defined by the appended claims.

[0016] Throughout this description, the terms "connected," "attached," and "coupled" are used to describe both a direct and an indirect connection (e.g., resistive and / or electrically conductive, e.g., an electrically conductive connection), a direct or indirect connection, and a direct or indirect coupling. In the figures, identical or similar elements are provided with identical reference numerals where appropriate.

[0017] According to various embodiments, the term "coupled" or "coupling" can be understood in the sense of a (e.g. mechanical, hydrostatic, thermal and / or electrical), e.g. direct or indirect, connection and / or interaction. Several elements can, for example, be coupled to one another along an interaction chain, along which the interaction can be exchanged, e.g. a fluid (then also referred to as fluid-electrically conductively coupled). For example, two coupled elements can exchange an interaction with one another, e.g. a mechanical, hydrostatic, thermal and / or electrical interaction. A coupling of several vacuum components (e.g. valves, pumps, chambers, etc.) to one another can have them fluid-electrically conductively coupled to one another. According to various embodiments, "coupled" can be understood in the sense of a mechanical (e.g. physical orA coupling can be understood as a physical coupling, e.g., through direct physical contact. A coupling can be configured to transmit a mechanical interaction (e.g., force, torque, etc.).

[0018] The term "sputtering" refers to the atomization of a material (also referred to as coating material or target material) using a plasma. The atomized components of the target material are thus separated from one another and can, for example, be deposited elsewhere to form a layer. Sputtering can be carried out using a so-called sputtering device, which may have a magnet system (in which case also referred to as a magnetron). The target material can be provided by a so-called sputtering target, which can, for example, be tubular (in which case also referred to as a tubular target) or plate-shaped (in which case also referred to as a plate target). To generate the plasma, a voltage can be applied to the sputtering target (also referred to as the target for short), so that the sputtering target is operated as a cathode. Even if the voltage is an alternating voltage, the term "cathode" is retained.

[0019] For sputtering, the sputtering target can be arranged in a vacuum processing chamber (also referred to simply as a vacuum chamber) so that sputtering can take place in a vacuum. For this purpose, the ambient conditions (the process parameters) within the vacuum processing chamber (e.g., process pressure, temperature, gas composition, etc.) can be set or regulated during sputtering. For example, a working gas can be provided within the vacuum processing chamber, which designates the plasma-forming gas or the plasma-forming gas mixture. The vacuum processing chamber can, for example, be designed to be airtight, dusttight, and / or vacuum-tight, so that a gas atmosphere with a predefined composition (also referred to as the working atmosphere) or a predefined pressure (also referred to as the working pressure or process pressure) can be provided within the vacuum processing chamber (e.g., according to a setpoint).The vacuum chamber may be arranged such that a vacuum (ie a pressure less than 0.3 bar) and / or a pressure in a range of approximately 1 mbar to approximately 1 mbar (in other words, fine vacuum) or less can be provided therein, e.g. a pressure in a range of approximately 10. 3 mbar to approximately 10 7 mbar (in other words high vacuum) or less, e.g. a pressure of less than high vacuum, e.g. less than approximately 10 7 mbar (in other words, ultra-high vacuum). The lowest pressure achievable in the vacuum chamber is also referred to as the residual vacuum.

[0020] A plasma can be formed using a so-called working gas (also referred to as a plasma-forming gas). According to various embodiments, the working gas can comprise a gaseous material that is inert, in other words, that participates in few or no chemical reactions. A working gas can, for example, be or become defined by the target material used and can be or become adapted to this. For example, a working gas can comprise a gas or a gas mixture that does not react with the target material to form a solid or is even inert towards it. The working gas can, for example, comprise a noble gas (e.g., helium, neon, argon, krypton, xenon, radon) or several noble gases. The plasma can be formed from the working gas, which, for example, essentially causes the target material to be atomized.If a reactive gas is used, it may exhibit a higher chemical reactivity than the working gas, e.g., with respect to the target material. In other words, the atomized target material can react more quickly with the reactive gas (if present) (i.e., form more reaction product per unit time) than with the working gas (e.g., if it reacts chemically with the working gas at all). The reactive gas and the working gas can be supplied together or separately as a process gas (e.g., as a gas mixture), for example, using the gas supply device.

[0021] It should be understood that what is described herein for sputtering can apply analogously to any other coating process, e.g., physical vapor deposition. In general, physical vapor deposition (e.g., sputtering) involves transferring the chemical composition of the target or coating material into the layer to be formed.

[0022] In order to effectively atomise the target material (also known as sputtering), the target material can be rotated around the magnet system. For this purpose, the target material can be configured in a tubular shape, as a so-called tubular target or tubular cathode, whereby the magnet system can be arranged inside the tubular target so that the tubular target can be rotated around the magnet system. For example, the magnet system can also be arranged outside the tubular target. The tubular target can, for example, have a tube on which the target material can be attached as a layer on an outer surface of the tube and can partially cover the surface of the tube. However, the tubular target can also be formed from the target material.

[0023] According to various embodiments, a magnetron cathode may have an extension (e.g., along a rotation axis, i.e., a length) that is greater than or equal to approximately 1 m, e.g., greater than or equal to approximately 2 m, e.g., greater than or equal to approximately 3 m or approximately 4 m, e.g., in a range from approximately 1 m to approximately 6 m. According to various embodiments, a magnetron cathode or its target material may have an extension (e.g., width or diameter, e.g., transverse to its rotation axis or transverse to its longitudinal extension) in a range from approximately 10 cm to approximately 50 cm (e.g., for planar targets, greater than approximately 20 cm), e.g., in a range from approximately 10 cm to approximately 40 cm, e.g., in a range from approximately 10 cm to approximately 30 cm, e.g., in a range from approximately 10 cm to approximately 20 cm (e.g., if the target is tubular), e.g., in a range from approximately 12 cm to approximately 18 cm. e.g.in a range of approximately 15 cm to approximately 16 cm. For example, a tubular magnetron cathode may have an inner diameter of less than or equal to 150 mm, e.g., less than or equal to 125 mm. For example, a tubular magnetron cathode may have an outer diameter of less than or equal to 200 mm, e.g., less than or equal to 133 mm.

[0024] The tubular target can be or become rotatably mounted at opposite end sections by means of so-called end blocks, wherein the end blocks can provide a supply of power (e.g., electrical power and cooling fluid) to the tubular target. More generally, reference is made herein to a storage device which can have one or more end blocks for storing a tubular target. If the storage device has two end blocks, one of the end blocks (the so-called drive end block) can have a drive train coupled to a drive (also referred to as target drive) for rotating the tubular target; and the other of the end blocks (the so-called media end block) can have a fluid line for supplying and removing cooling fluid (e.g., a water-based mixture), which can be passed through the target. The two end blocks are mounted, for example, suspended from a chamber ceiling (i.e., a chamber lid).

[0025] However, it is also possible to use just one end block (also called a compact end block), which contains the drive train and the fluid line and thus provides the functions of a drive end block and a media end block together. The side of the tubular target opposite the compact end block can, for example, project freely (i.e., hang freely), which is referred to as a cantilever configuration. The compact end block can be mounted in the cantilever configuration on a side wall of the vacuum chamber, through which the rotational axis of the tubular target extends. The side of the tubular target opposite the compact end block can, however, also be supported by means of a bearing block (illustratively a counter bearing), which is referred to as a bearing block configuration. The bearing block can also be provided by means of a passive end block, i.e., an end block which exchanges neither energy nor material with the tubular target, but only supports it.

[0026] The bearing device can generally (e.g. in the case of a tubular target and a plate target) have a carrier (also referred to as a magnet carrier) which is designed to hold the magnet system. The magnet carrier can, for example, be hollow (e.g. comprising a tube) and can be fluidically conductively coupled at the end to an end block which holds the magnet carrier (e.g. with its fluid line), so that the end block can exchange the cooling fluid with the end block. On the side opposite the end block, the tube can, for example, be closed at the end and have a lateral opening there through which the cooling fluid can pass. The magnet carrier can be round or polygonal, e.g. comprising a round tube or an angled tube. The magnet carrier and / or the magnet system can have a length (extension along the axis of rotation) in a range from approximately 1 m to approximately 6 m, e.g. in a range from approximately 2 m to approximately 5 m.

[0027] According to various embodiments, the vacuum chamber can be provided by means of a chamber housing in which one or more chambers can be provided. The chamber housing can, for example, be coupled to a pump arrangement, e.g. a vacuum pump arrangement (e.g. gas-electrically conductive), for providing a negative pressure or a vacuum (vacuum chamber housing), and can be designed so stably that it withstands the effects of air pressure in the pumped-out state. The pump arrangement (comprising at least one vacuum pump, e.g. a high-vacuum pump, e.g. a turbomolecular pump) can make it possible to pump out part of the gas from the interior of the processing chamber, e.g. from the processing space. Accordingly, one or more vacuum chambers can be provided in one chamber housing. In other words, the chamber housing can be designed as a vacuum chamber housing.a coating chamber can be set up as a vacuum chamber.

[0028] Radio frequency (RF) is defined as a frequency in the range from approximately 20 kHz (kilohertz) to approximately 300 GHz (gigahertz), in particular a frequency in the range from approximately 1 megahertz (e.g., approximately 10 megahertz) to approximately 50 megahertz (e.g., approximately 15 megahertz). If the frequency of an alternating voltage is a radio frequency, it is also referred to as a high-frequency voltage.

[0029] According to various embodiments, the high-frequency voltage (also referred to as RF voltage or alternating voltage in the RF range) is selectively coupled into the sputtering target by electrodes, so-called coupling electrodes. Each of the plurality of electrodes can be assigned a section of the sputtering target into which the respective electrode couples the alternating voltage. The coupling can be carried out, for example, in a contact-free capacitive manner (particularly low-wear and / or suitable for a target material with low electrical conductivity), a sliding capacitive manner (particularly homogeneous), and / or a sliding galvanic manner (e.g., ohmically conductive). For this purpose, the coupling electrodes can be coupled to the target in a capacitive and / or ohmically conductive manner (e.g., galvanically conductive) depending on the type of coupling and / or the electrical conductivity of the target.

[0030] According to various embodiments, depending on the type of coupling, the coupling electrodes can be supported on the target, e.g., by sliding thereon and / or by means of a support wheel, so that the position of the coupling electrodes depends on the geometry of the tube target. It can be understood that what is described herein in this regard applies analogously to the fact that the dependence of the position of the coupling electrodes on the geometry of the tube target is implemented contactlessly, e.g., when the position of the coupling electrodes is influenced by means of an actuator.

[0031] Electrically conductive is understood herein to mean having an electrical conductivity (e.g. conductance and / or for direct current) of more than approximately 1 Siemens per meter (S / m), e.g. more than approximately 10 3 S / m or more than approximately 10 5S / m. Electrically insulating can be understood herein as having (e.g. conductance and / or for direct current) an electrical conductivity of less than approximately 10 6 Siemens per meter (S / m), e.g. less than approximately 10 ® S / m, than approximately 10 10 S / m or approximately 10 12 Ohmic conductivity is understood here as electrically conductive for direct current.

[0032] An electrical coupling can generally have a susceptance and / or a conductance. If two components are electrically coupled to one another, it can be understood that an electrical coupling exists between them, by means of which they can exchange electrical power. An ohmic coupling is understood here as providing an ohmic conductivity (also referred to as conductance). A capacitive coupling is understood here as providing (e.g. only) a susceptance, in particular (e.g. only) being electrically conductive (in the sense of a susceptance) for alternating current (e.g. in the HF range) and / or having an impedance that decreases with increasing frequency of the alternating current. A dielectric (also referred to as dielectric material) can be understood here as a material (e.g. a solid) in which the charge carriers present are localized (i.e., not freely movable). The dielectric material can be electrically (e.g. ohmic) insulating.

[0033] The term "non-magnetic" can be understood as essentially magnetically neutral, e.g., also slightly paramagnetic or diamagnetic. The term "non-magnetic" can, for example, be understood as having a magnetic permeability of essentially 1, i.e., in a range from approximately 0.9 to approximately 1.1. Examples of non-magnetic materials include: graphite, aluminum, platinum, copper, non-magnetic stainless steel, and a ceramic (e.g., an oxide).

[0034] Fig.1 A and Fig.1 B each illustrate various aspects of a coating device 100 according to various embodiments in a schematic detailed view. For example, Fig.1 A shows the coating device 100 with a view along the direction 103 (also referred to as reference direction 103) of the rotation axis 131, along which the coating device 100 or at least the sputtering target (not shown) are, for example, longitudinally extended. The coating device or at least the sputtering target can, for example, have a length (extension along the rotation axis 131) of more than approximately 2 m (meters) and / or less than approximately 6 m, e.g., in a range from approximately 2 m to approximately 5 m and / or more than 3 m. For example, Fig.1 B shows the coating device 100 with a view of the rotation axis 131, e.g.,along the direction 101 (also called transverse direction 101), along which the coating device 100 is transversely extended.

[0035] According to various embodiments, the coating device 100 can comprise a bearing device 130 configured to rotatably support a sputtering target 10 (also referred to as target for short), e.g., a tubular sputtering target 10. For example, the bearing device 130 can provide a rotation axis 131 and be configured to set the target 10 in a rotational movement about the rotation axis 131, e.g., by being configured to generate a torque or at least to transmit it to the target 10. The rotation axis 131 can therefore also be referred to herein as the rotation axis 131 of the target 10.

[0036] According to various embodiments, the coating device 100 can have a plurality of electrodes 110, so-called coupling electrodes 110, which are configured to couple an alternating voltage into the target 10. According to various embodiments, the plurality of electrodes can be arranged one behind the other in a row along the rotation axis 131, as shown by way of example in Fig. 1B, among others.

[0037] The AC voltage can be coupled in capacitively, for example, e.g. without an ohmically conductive (i.e. DC-conductive) connection between the plurality of electrodes and the target 10 (e.g. if they are galvanically separated from one another). The ohmically conductive connection between the plurality of electrodes and the target can, for example, not be present if the target is dielectric and / or if the coupling electrodes 110 are galvanically separated from the target, at least by means of a dielectric support body (not shown) which supports each of the electrodes on the target 10. If the ohmically conductive connection between the plurality of electrodes and the target is missing, each of the electrodes 110 can form a capacitor with the target 10, by means of which the AC voltage is coupled in.

[0038] It can be understood that the electrodes 110 can alternatively or additionally be ohmically coupled to the target 10, e.g., by means of an ohmically conductive connection. For example, as an alternative to capacitive coupling, the coupling can be carried out by means of an electrically conductive connection between the plurality of electrodes and the target 10. If reference is made herein to the capacitive coupling between the electrodes 110 and the target 10, it can be understood that the electrodes 110 can alternatively or additionally be ohmically coupled to the target 10, for which what has been described with regard to the capacitive coupling can apply analogously. The electrical power that is coupled into the target by means of the alternating voltage is preferably conveyed by means of the capacitive coupling, even if the electrodes 110 are ohmically coupled to the target 10.

[0039] Optionally, immediately adjacent electrodes 110 may be physically separated from each other, e.g., by means of a dielectric support body and / or by means of a distance 120e from each other.

[0040] If the target 10 is present, the electrodes 110 can be arranged at a distance 120o (also referred to as target distance 120o) from the target 10, e.g., without contact with respect to the target 10, and thus at a distance 120t from the rotation axis 131 (also referred to as rotation axis distance 120t) which is greater than the outer diameter of the target.

[0041] Due to the sputtering of the target, the outer diameter of the target may decrease during sputtering, e.g., unevenly along the axis of rotation. To compensate for this, the plurality of electrodes 110 can be movable, e.g., movably mounted, (e.g., toward or away from the axis of rotation) relative to the axis of rotation and / or relative to one another. For example, each electrode of the plurality of electrodes 110 can be movable, e.g., movably mounted, relative to one or more of the other electrodes 110. This makes it easier, for example, to adjust the target distance 120o for each electrode of the plurality of electrodes 110 according to a desired distance, e.g., to adjust it individually for each electrode, e.g., by moving each electrode toward or away from the axis of rotation. Optionally, for example, a distance 120e between two adjacent electrodes, also referred to as electrode distance 120e, can be changed, e.g., reduced and / or increased.Thus, for example, a homogeneity of an alternating electric field that is generated due to the alternating voltage and that is coupled into the target 10 can be increased.

[0042] Each of the electrodes may have an electrically conductive surface 110s (also referred to as an electrode surface) facing the rotation axis 131. The support body may optionally contact the surface 110s and / or the target, e.g., supporting each of the electrodes against the target 10.

[0043] It can be understood that the desired distance between the target and the multiple electrodes can be smaller than a dark-field distance. This inhibits plasma formation in the gap between the target and the multiple electrodes. A dark-field distance is defined as a distance according to Paschen's law (the graphical representation of which is also called a Paschen curve) at which the breakdown voltage as a function of gas pressure is greater than the amplitude of the alternating voltage.

[0044] According to various embodiments, a number of the plurality of electrodes 110, an extension of each of the plurality of electrodes 110 along the rotation axis 131, and / or the distance 120e between adjacent electrodes from one another (also referred to as electrode spacing 120e) can be adapted to the properties of the AC voltage and / or to the geometry (e.g., the length) of the target 10, e.g., according to a specification. The specification can, for example, represent the number of electrodes per path (e.g., reference path) along the rotation axis 131 (then also referred to as path density).

[0045] For example, a greater path density can lead to greater homogeneity (e.g., a more homogeneous distribution) of the spatial power distribution coupled into the target. For example, the plurality of electrodes can have at least one electrode per reference path (also referred to as reference length) along the rotation axis, so that at least one electrode can be arranged per reference path. The reference length can, for example, be in a range from approximately 0.75 m (meters) to approximately 1.25 m or less, e.g., approximately 1 m or less. For example, a length of each of the electrodes along the rotation axis 131 can be greater than 50% (e.g., 75% or 90%) of the reference length and / or less than the reference length. For example, the electrode spacing 120e can be in a range from approximately 0.5 m to approximately 0.01 m.

[0046] In an exemplary implementation, the path density can be one electrode per meter or more, e.g., one electrode per meter of target length 10 or more. Alternatively or additionally, the length of each of the electrodes can be less than 1 m and / or greater than 0.75 m.

[0047] According to various embodiments, directly adjacent electrodes can differ from one another, e.g., in their desired distance from the axis of rotation (e.g., in the case of a partially worn target) and / or in their length along the axis of rotation. For example, an electrode that forms the beginning and / or the end of the row of several electrodes arranged one behind the other can differ from the electrode immediately adjacent to it, e.g., in its desired distance from the axis of rotation (e.g., in the case of a partially worn target) and / or in its length along the axis of rotation. This makes it possible to compensate for edge effects when coupling the alternating voltage into the target. For example, the plurality of electrodes 110 can be distributed unevenly along the length of the target 10, whereby the homogeneity of the coupling of the alternating voltage into the target 10 can be increased.

[0048] According to various embodiments, the coating device 100 can have a positioning device 120. The positioning device 120 can be configured to position the plurality of electrodes 110 of the coating device 100 relative to the rotation axis 131 of the target 10 and / or relative to one another. For example, the position of each of the plurality of electrodes 110 can be based on the desired distance and / or a parameter representing a geometry of the target 10. For example, the parameter can represent an outer diameter of the target 10, e.g., a spatial distribution of the outer diameter along the rotation axis 131, and thus clearly a wear of the target 10. Alternatively or additionally, the parameter can represent a length of the target and / or a wall thickness of the target. Alternatively or additionally, the parameter can represent a sputtering material, e.g.,represent a chemical composition of the sputtering material, the target.

[0049] For example, the position of each of the plurality of electrodes can be adjusted, e.g., by means of the positioning device 120, such that the target distance 120o is the desired distance or deviates from the desired distance by at least less than approximately 20% (e.g., 10%). Alternatively or additionally, the position of each of the plurality of electrodes can be adjusted, e.g., by means of the positioning device 120, such that a predetermined criterion is met. The predetermined criterion can be met, for example, if the target distance 120o and / or the desired distance are smaller than the dark field distance. Thus, for example, the formation of a plasma between the plurality of electrodes 110 and the target 10 can be inhibited. For example, the fulfillment of the specific criterion can be integrated into the previously described parameter.

[0050] Fig. 1C and Fig. 1D each illustrate various aspects of the coating device 100 according to various embodiments in a schematic detailed view, analogous to Fig. 1A and Fig. 1B, in which the positioning device 120 has one (or more) linear bearings 124 and / or one (or more) gears 122, which are configured to position the plurality of electrodes 110. For example, the positioning device 120 can have a linear bearing (e.g., a respective individual linear bearing) per electrode, which provides the electrode with a degree of freedom toward or away from the axis of rotation. Of course, two or more electrodes can also be coupled to the same linear bearing 124.

[0051] For example, by means of the linear bearing 124, a respective electrode of the plurality of electrodes can be movably mounted relative to the rotation axis 131 in order to be able to change the target distance 120t. For example, the respective electrode can be displaced toward or away from the rotation axis according to a degree of freedom provided by the linear bearing 124, so that the rotation axis distance 120t changes.

[0052] For example, the gear mechanism 122 can be used to influence the position of the plurality of electrodes 110 relative to one another, and thus the electrode spacing 120e. For example, the gear mechanism 122 can be configured to decrease and / or increase the electrode spacing 120e. For example, the electrode spacing 120e can be a function of the parameter and / or depend on the criterion to be met (e.g., be determined based on this). For example, the gear mechanism 122 can be configured to position the plurality of electrodes 110 relative to one another. For example, instead of or in addition to the gear mechanism 122, the coating device 100 can have a (e.g., motor-driven) actuator (e.g., an electric motor) which supports, supplements, or optionally takes over the described functionality of the gear mechanism 122. For example, the coating device 100 can have a control loop, and the control loop can be configured to control the actuator.Alternatively, the actuator can be part of the control loop, e.g. if it is set up to adjust the gear.

[0053] Fig. 2A to Fig. 2D each illustrate various aspects of the coating device 100 according to various embodiments in a schematic detailed view in the direction of reference direction 103, in which each of the plurality of electrodes 110 is planar, e.g., plate-shaped, and / or at least the electrode surface facing the axis of rotation is concave. This favors each of the plurality of electrodes 110 forming a capacitor with the target 10, which favors the capacitive coupling of the alternating voltage into the target 10. It can be understood that the electrode surface 110s of each of the plurality of electrodes 110 is at least partially (e.g., completely) curved and / or at least partially (e.g., completely) uncurved. By way of example, an electrode with an uncurved surface 110s, see Fig.2B and Fig.2D, as well as an electrode with a curved surface 110s, see Fig.2A and Fig.2C, are shown.For example, the curved one.

[0054] Electrode surface 110s can be a surface of rotation of the axis of rotation 131. The curved surface 110s can, for example, be a concavely curved surface 110s that faces, for example, the axis of rotation 131. For example, the electrode can be in the form of a ring segment. Alternatively or additionally, each of the electrodes can be shaped such that it encloses the target (e.g., a projection thereof) in an angular range of more than 100°, e.g., more than 120°, e.g., more than 150°. This allows, for example, the alternating electric field emanating from the electrode 110 to be coupled more homogeneously into the target 10 and / or a capacitance of the capacitor formed from the electrode and the target to be increased, which promotes the coupling of the alternating voltage.

[0055] Optionally, the positioning device 120 can have a plurality of rotatably mounted support wheels 126 as exemplary support bodies, as shown by way of example in Figures 2C and 2D. Each of the support wheels 126 can be coupled to one of the plurality of electrodes 110 in order to support the electrode on the target 10. This favors, for example, providing a time-invariant target distance 110t between each of the electrodes. Each of the support wheels 126 can be configured to roll on the target 10, e.g., when the target is subjected to a rotational movement. This prevents damage to the target 10. It can be understood that what has been described for the support wheels 126 can apply analogously to support bodies of a different type (e.g., a different geometry). For example, a support body rigidly coupled to the electrode can be used, which slides on the target 10 if damage to the target 10 is acceptable or at least minimal.

[0056] For example, the plurality of support wheels 126 can each be coupled to one of the plurality of electrodes 110 such that the position of the respective electrode is a function of the geometry of the sputtering target. For example, the positioning device 120, e.g., a spring element thereof, can be configured to transmit a force to each of the electrodes, which presses the support wheel, by means of which the electrode is supported on the target, against the target 10, so that the target distance 110t remains as invariant as possible, even if the cross-section of the target 10 is not circular and / or changes during the sputtering process. For example, the positioning device 120 can each have a single support wheel (see, for example, Fig. 2D) or several support wheels (see, for example, Fig. 2C) of the plurality of support wheels 126 per electrode.

[0057] According to various embodiments, the plurality of support wheels 126 may include one or more support wheels of a first type and / or one or more support wheels of a second type.

[0058] For example, a support wheel of the first type can galvanically (e.g., ohmically) couple the electrode corresponding to the support wheel of the first type to the target. For example, the support wheel of the first type can be electrically conductive, e.g., comprise an electrically conductive material, e.g., consist of it. An electrically conductive support wheel enables, for example, a galvanic coupling or a combination of a galvanic and a capacitive coupling between the respective electrode and the target 10 if a sputtering target material of the target 10 is also electrically conductive.

[0059] For example, a support wheel of a second type can galvanically (e.g., ohmically) separate the electrode corresponding to the support wheel from the target. For example, the support wheel of the second type can be electrically insulating (e.g., not electrically conductive), e.g., dielectric. For example, the support wheel of the second type can comprise, e.g., consist of, an electrically insulating material, e.g., a dielectric material. A support wheel comprising a dielectric material makes it possible, for example, to increase the capacitance of the capacitor formed from the electrode and the target.

[0060] Fig.3A illustrates various aspects of the coating device 100 according to various embodiments in a schematic detailed view in the direction of the transverse direction 101.

[0061] According to various embodiments, the coating device 100 may further comprise a circuit 140, e.g., a switching circuit 140, which couples the plurality of electrodes 110 to one another. The switching circuit may, for example, be configured to couple an alternating voltage provided to the circuit 140 into the target 10 in phase by means of the electrodes 110. For example, all electrodes 110 may couple the alternating voltage into the target 10 with the same phase.

[0062] According to various embodiments, the coating device 100 may comprise an AC voltage source 141, e.g., an AC voltage generator 141, configured to provide the AC voltage. For example, the AC voltage source 141 may be configured to provide the AC voltage at a high frequency, e.g., at a frequency in a range from approximately 1 megahertz (e.g., approximately 10 megahertz) to approximately 50 megahertz (e.g., approximately 15 megahertz). For example, the AC voltage source 141 may be coupled to the circuit.

[0063] Fig. 3B and Fig. 3C each illustrate various aspects of circuit 140 according to various embodiments in a schematic view. Circuit 140 may, for example, comprise a star connection that electrically couples the multiple electrodes to one another via a node coupled to AC voltage generator 141.

[0064] According to various embodiments, the circuit 140, e.g. its star connection, can have one or more than one electrical actuator 142 that is configured to influence an impedance and / or a capacitance by means of which two of the plurality of electrodes 110 are coupled to one another. For example, each electrode can be coupled to the node of the star connection by means of an electrical actuator 142 assigned to it. For example, the electrical actuator 142 can be configured to influence a phase of the alternating voltage and / or to ensure that the alternating voltage arrives at the electrodes in phase (e.g. also referred to as phase-synchronous). For example, the phase can be shifted by changing an impedance of the electrical actuator, e.g. by changing an inductance and / or a capacitance of the electrical actuator.This allows, for example, an in-phase coupling of the alternating voltage into the target 10 and can thus inhibit the occurrence of compensating currents within the target 10 between sections assigned to different electrodes.

[0065] The electrical actuator 142 can, for example, comprise a capacitive component (e.g., a capacitor) that couples the associated electrode to electrical ground or another reference potential and / or is connected in series between two electrodes. For example, the capacitive component can have an electrical capacitance that is variable, e.g., according to a desired capacitance value. This is illustrated by way of example in Fig. 3C, in which each of the electrical actuators 142 has an adjustable capacitor C1-C4 that is coupled to electrical ground or another reference potential.

[0066] By way of example, in Fig. 3C, the respective adjustable capacitors C1-C4, the plurality of electrodes 110, and the target 10 are combined in a first functional group 144. The first functional group represents, by way of example, the capacitive feed and the adjustable capacitors as tuning elements.

[0067] Alternatively or additionally, each electrical actuator 142 may, for example, comprise an inductive component (e.g., a coil) that couples the node to the associated electrode (e.g., connected in series between them) and / or is connected in series between two electrodes. For example, the inductive component may have an electrical inductance that is variable, e.g., according to a desired inductance value. This is illustrated by way of example in Fig. 3C, in which each of the electrical actuators 142 comprises a coil L1-L4.

[0068] By way of example, in Fig. 3C, the respective coils L1-L4 are combined in a second functional group 145, which exemplifies a star-shaped connection for power supply. Alternatively or additionally, the electrical actuator 142 can comprise, for example, a resistive component, e.g., an electrical resistor (not shown). For example, the resistive component can comprise an electrical resistance that is variable.

[0069] For example, each electrical actuator 142 may be configured as an oscillating circuit (e.g., LC circuit) having a coil and a capacitor and coupling the associated electrode to the node of the star circuit.

[0070] Optionally, the circuit 140 can further comprise an additional electrical actuator 143 (also referred to as matchbox 143). The matchbox is configured, for example, to influence a load impedance of the magnetron, e.g., to adapt it to an impedance of the AC voltage source 141. For example, the matchbox can be configured to reduce power reflection, e.g., to reduce it to zero. Analogous to the electrical actuator 142, the matchbox 143 can also comprise one or more capacitive components, one or more inductive components, and / or one or more resistive components. By way of example, Fig. 3C shows that the matchbox 143 comprises a capacitive component, a capacitor C1'.

[0071] Fig. 3D illustrates various aspects of the coating device 100 according to various embodiments in a perspective schematic view, illustrating, by way of example, the circuit 140 coupled to the plurality of electrodes 110. The plurality of electrodes 110 are illustrated, by way of example, with a concave surface that is at a distance (e.g., a surface distance) from the target 10. This allows the AC voltage to be capacitively coupled into the target 10 by means of the plurality of electrodes.

[0072] Fig.4 illustrates various aspects of the coating device 100 according to various embodiments in a schematic detailed view looking along the transverse direction 101.

[0073] According to various embodiments, the bearing device 130 may include a magnet system 132. For example, the rotation axis 131 may be arranged between the magnet system 132 and the plurality of coupling electrodes 110.

[0074] According to various embodiments, the bearing device 130 can be configured to support the target 10, e.g., to support it rotatably. For example, the target and / or the magnet system 132 can have a length along the rotation axis 131 that is greater than a reference (also referred to as a size reference). Alternatively or additionally, the bearing device 130 can have two end blocks 134, or a pair of end blocks 134 and associated counterbearings, or one end block 134 without a counterbearing (also referred to as a cantilever configuration, in which the magnetron is supported on only one side by means of the end block).

[0075] For example, the axis of rotation can be provided by the end block (e.g., with or without a counterbearing) or by the two end blocks, e.g., between them. Alternatively or additionally, the two end blocks, or the end block and the counterbearing, can be spaced apart by a distance greater than the size reference. It should be understood that what is explained herein in the specific context of one or two end blocks can apply analogously to any other type of support (e.g., for any other number of end blocks) for the magnetron, e.g., single-sided or double-sided.

[0076] For example, the size reference may be greater than approximately 2 m (meters) and / or less than approximately 6 m, e.g. in a range from approximately 2 m to approximately 5 m and / or greater than 3 m or than 4 m.

[0077] The two end blocks 134 (or the one end block 134 and the counter support) can, for example, be configured to rotatably support the target 10 between them. For example, the end block, e.g., the two end blocks 134, can be configured to allow a cooling medium (e.g., cooling water) to flow through the interior of the target 10 to thereby cool the target 10. This can, for example, prevent the electrodes from being arranged within the target.

[0078] Fig.5 illustrates a method 500 for operating a coating device in a schematic flow diagram.

[0079] The method 500 may include, at 510, coupling an alternating voltage into a tubular target. The alternating voltage may be coupled into the target by means of a plurality of movably mounted electrodes. The plurality of electrodes may be arranged in a row along a rotational axis of the sputtering target. The coupled alternating voltage may, for example, supply energy to a plasma to which the target is exposed.

[0080] Furthermore, the method 500 may include, at 520, changing a position of the plurality of electrodes. For example, the position of the plurality of electrodes may be changed relative to one another and / or relative to the rotation axis of the target. Furthermore, the position may be changed depending on a parameter representing a geometry of the sputtering target.

[0081] Method 500 may optionally further include atomizing the tubular target, which is rotated about the rotation axis, using the plasma. Alternatively or additionally, thermal energy can be extracted from the target, i.e., it can be cooled. This can be achieved, for example, by supplying a cooling fluid to the target and then removing it again.

[0082] According to various embodiments, the use of a plurality of movably mounted electrodes for coupling an alternating voltage into a target is described herein. The plurality of electrodes can be arranged one behind the other in a row along a rotational axis of the target, and their position can be changed relative to one another and / or to the rotational axis depending on a parameter, e.g., by means of a positioning device. The parameter can, among other things, represent a geometry of the target, as described herein. According to various embodiments, a coating device is provided that can improve the homogeneity of a sputtering process for long tubular cathodes and thus simplify the sputtering of long target tubes based on high-frequency alternating voltages.

[0083] According to various embodiments, it has been recognized that the propagation of electromagnetic waves along the tubular cathode can be problematic. It has been clearly recognized that although a standing wave can form along the tubular cathode when an alternating voltage is fed into it from one side or two sides by means of the end blocks, this does not allow homogeneous distributions (e.g. an inhomogeneity of < 5%) to be achieved if the tubular cathode is more than approximately one meter long. This can hinder the practical application of high-frequency magnetrons which have such long tubular cathodes. According to various aspects, however, it has been recognized that this problem can be solved by feeding (e.g. coupling) the alternating voltage into the tubular cathode at several points (e.g. using respective electrodes) on the tubular cathode. For example, the alternating voltage can be fed in at distances between 0.75 m and 1.25 m (e.g. approx.1 m).

[0084] According to various embodiments, the alternating voltage can be fed into the tube cathode multiple times in similarly long sections. The feed can be made, for example, at intervals of approximately 1 m (e.g., between 0.75 m and 1.25 m). The exact length of the sections can be determined and specified according to requirements. In principle, the more feeds, the more homogeneous the distribution of the alternating voltage (e.g., the resulting field) can be. However, with a higher number of electrodes, problems can increase, e.g., with regard to arc detection, technical complexity, symmetrization, etc. For example, too many and too short sections can be problematic. For example, section lengths in the range between 0.75 m and 1 m can be practical and therefore advantageous. Deviations from this are possible, however, whereby the aforementioned problems must be addressed individually and, if necessary, compensated for.Furthermore, the lengths of the sections at the respective ends of the tube cathode, also referred to as tube ends, may deviate from the range given as an example.

[0085] According to various embodiments, the wave characteristics of the coupled alternating voltage in the tube ends, which are accommodated in so-called end blocks for storage and drive purposes, can differ from the wave characteristics of the "inner" tube sections of the tube cathode. The "inner" sections of the tube cathode refer to sections located between the sections at the two tube ends on the front sides of the tube cathode (e.g., "outer sections"). To match the wave characteristics, the lengths of the electrodes at the tube ends can differ from the electrodes in the inner sections of the tube cathode.

[0086] According to various embodiments, it was further recognized that the AC voltage should be supplied to all sections of the tube cathode in phase-synchronization, thereby reducing the occurrence of compensating currents on the tube cathode between different sections. This can be achieved, for example, by means of a circuit, e.g., a star-shaped connection of the electrodes. The circuit is set up, for example, so that all branches of the star-shaped connection have the same wave properties (e.g., the same phase, the same amplitude). To enable this equalization of the wave properties, an electrical actuator (e.g., also referred to as a tuning element) can be provided in each branch. A central power supply for the circuit can be provided by means of a voltage generator (e.g., a high-frequency generator) and via a so-called match box at the star point.

[0087] There are various options for directly feeding the alternating voltage into the individual sections of the tube cathode.

[0088] In a first case, the alternating voltage can be fed capacitively into the tubular cathode. For this purpose, an electrode (e.g., a curved electrode, e.g., a round sheet) can be installed above each section of the tubular cathode. For example, the (curved) electrodes can partially enclose the respective section of the tubular cathode and together with it form a capacitor. The distance between the tubular cathode and the respective electrode must be so small that no plasma can form in the space between the tubular cathode and the respective electrode. For example, the distance must be smaller than the dark field distance. This approach can be used, for example, with intrinsic target materials.

[0089] In a second case, the alternating voltage can be fed directly into the tubular cathode, e.g., with electrically conductive target materials. The design of the coating device is fundamentally similar to the first case, but the electrodes are additionally electrically connected to the tubular cathode. For example, the multiple electrodes can be supported directly on the tubular cathode by means of support rollers. The support rollers can then be used, for example, to create a galvanic coupling between the respective electrode and the tubular cathode. This can result in a superposition of a capacitive coupling and a galvanic coupling between the multiple electrodes and the tubular cathode.

[0090] In a third case, the described design of the coating device of the second case, in which the coating device has support rollers, can be applied to intrinsic target materials (cf., for example, the first case). However, for such target materials, no galvanic coupling results. Therefore, in this case, it is advantageous if the support rollers are not electrically conductive. Thus, for example, the same conditions can be created at all locations along the entire length of the tubular cathode. Furthermore, the support rollers can enable a constant distance between the target and the electrodes over the entire sputtering period, as described herein.

[0091] In the following, various examples are described which relate to what has been described above and shown in the figures.

[0092] Example 1 is a coating device that can comprise: a bearing device that provides a rotational axis and is configured to set a tubular sputtering target mounted by means of the bearing device into a rotational movement around the rotational axis and / or to supply a cooling fluid (e.g. a cooling liquid, e.g. cooling water) to said target; a plurality of movably mounted (e.g. non-magnetic) coupling electrodes that are arranged one behind the other in a row along the rotational axis for coupling an alternating voltage (e.g. with a high frequency) into the sputtering target; and a positioning device that is configured to determine a position of the plurality of coupling electrodes relative to one another (e.g. by means of a translation towards or away from the rotational axis) and / or relative to the rotational axis (e.g.by means of a translation towards or away from the axis of rotation) depending on a parameter that represents a geometry of the sputtering target.

[0093] Example 2 is a coating device according to Example 1, which may optionally further comprise: a circuit which electrically couples the plurality of coupling electrodes to one another and is configured to couple the alternating voltage provided to the circuit into the sputtering target in phase by means of the coupling electrodes.

[0094] Example 3 is a coating device according to Example 2, wherein the circuit comprises, for example, an electrical actuator which is configured to influence an impedance and / or a capacitance by means of which two of the plurality of coupling electrodes are coupled to one another.

[0095] Example 4 is a coating device according to any one of Examples 1 to 3, wherein each of the plurality of coupling electrodes is planar for capacitively coupling the alternating voltage into the sputtering target.

[0096] Example 5 is a coating device according to any one of Examples 1 to 4, wherein the positioning device is configured to influence a position of each coupling electrode of the plurality of coupling electrodes such that a distance of the coupling electrode from the sputtering target fulfills a criterion.

[0097] Example 6 is a coating device according to Example 5, wherein the criterion is met when the distance is smaller than a dark field distance.

[0098] Example 7 is a coating device according to any one of Examples 1 to 6, wherein the positioning device comprises, for each coupling electrode of the coupling electrodes, a linear bearing by means of which the coupling electrode is mounted so as to be movable toward or away from the axis of rotation.

[0099] Example 8 is a coating device according to any one of Examples 1 to 7, wherein the positioning device comprises a gear mechanism configured to influence the position of the plurality of coupling electrodes relative to one another as a function of the parameter.

[0100] Example 9 is a coating device according to any one of Examples 1 to 8, wherein the positioning device comprises, for each coupling electrode of the coupling electrodes, a support wheel coupled to the coupling electrode for supporting the coupling electrode on the sputtering target, for example such that the position of the plurality of coupling electrodes is a function of the geometry of the sputtering target.

[0101] Example 10 is a coating device according to Example 9, wherein the support wheel is configured to galvanically couple the coupling electrode to the sputtering target or to galvanically separate it from it.

[0102] Example 11 is a coating device according to Example 9 or 10, wherein the support wheel is dielectric or electrically conductive.

[0103] Example 12 is a coating apparatus according to any one of Examples 1 to 11, wherein the parameter comprises a spatial distribution of the diameter of the sputtering target.

[0104] Example 13 is a coating device according to any one of Examples 1 to 12, wherein the bearing device comprises a magnet system, and wherein the rotation axis is arranged between the magnet system and the plurality of coupling electrodes. The magnet system can be arranged, for example, between the target and the rotation axis.

[0105] Example 14 is a coating device according to any one of examples 1 to 13, wherein the positioning device is configured to influence the position of the plurality of coupling electrodes relative to one another by means of a movement (e.g., translation) of one or more than one first electrode of the plurality of electrodes toward or away from the axis of rotation, e.g., relative to a second electrode of the plurality of electrodes.

[0106] Example 15 is a coating device according to any one of examples 1 to 14, wherein the positioning device is configured to influence the position of the plurality of coupling electrodes relative to the axis of rotation by means of a movement (e.g., translation) of the plurality of electrodes (e.g., jointly) toward or away from the axis of rotation.

[0107] Example 16 is a coating device according to any one of Examples 1 to 15, which may optionally further comprise: an AC voltage source for providing the AC voltage.

[0108] Example 17 is a coating apparatus according to Example 16, wherein the AC voltage source is configured, for example, to provide the AC voltage at a frequency in a range of approximately 1 megahertz (e.g., 10 megahertz) to approximately 50 megahertz (e.g., 15 megahertz).

[0109] Example 18 is a coating device according to example 16 or 17, which can optionally further comprise: an additional electrical actuator (e.g., a matchbox) configured to influence an output-side impedance of the AC voltage source, by means of which the AC voltage source is coupled to the plurality of coupling electrodes. Example 19 is a coating device according to any one of examples 1 to 18, wherein the support device is further configured to supply the sputtering target with a cooling fluid.

[0110] Example 20 is a coating device according to any one of Examples 1 to 19, wherein each of the coupling electrodes has a concave surface facing the rotation axis.

[0111] Example 21 is a coating device according to any one of Examples 1 to 20, wherein an angular enclosure of each of the coupling electrodes with respect to the rotation axis is greater than 100 degrees (eg, greater than 120 degrees, eg, greater than 150 degrees).

[0112] Example 22 is a coating device according to any one of Examples 1 to 21, wherein at least one coupling electrode of the plurality of coupling electrodes is arranged per meter (e.g., per one meter) along the rotation axis.

[0113] Example 23 is a coating device according to any one of Examples 1 to 22, wherein the storage device is configured to store the sputtering target having an extension along the rotation axis of more than 2 (eg, more than 3, eg, more than 4) meters.

[0114] Example 24 is a coating apparatus according to any one of Examples 1 to 23, wherein the support device comprises two end blocks for rotatably supporting the sputtering target (eg, between the two end blocks), wherein a distance of the two end blocks from each other is greater than 2 (eg, more than 3, eg, more than 4) meters.

[0115] Example 25 is a coating apparatus according to any one of Examples 1 to 24, which may optionally further comprise: the tubular sputtering target.

[0116] Example 26 is a coating device according to any one of Examples 1 to 25, wherein the plurality of coupling electrodes comprises three or more coupling electrodes.

[0117] Example 27 is a method for operating a coating device, for example for operating the coating device according to any one of Examples 1 to 26. The method may comprise: coupling an alternating voltage into a tubular sputtering target by means of a plurality of movably mounted coupling electrodes arranged one behind the other in a row along a rotational axis of the sputtering target, for supplying a plasma (e.g., with electrical power) to which the sputtering target is exposed; and changing a position of the plurality of coupling electrodes relative to one another and / or to the rotational axis as a function of a parameter representing a geometry of the sputtering target.

[0118] Example 28 is a method according to Example 27, which may optionally further comprise: sputtering the tubular sputtering target, which is rotated about the rotation axis, using the plasma. Example 29 is a method according to Example 27 or 28, which may optionally further comprise: supplying a cooling fluid into the sputtering target to extract thermal energy.

[0119] Example 30 is the use of a plurality of movably mounted coupling electrodes which are arranged one behind the other in a row along a rotational axis of a sputtering target and whose position relative to one another and / or to the rotational axis is changed depending on a parameter representing a geometry of the sputtering target, for coupling an alternating voltage into the sputtering target.

[0120] Example 31 is configured as any one of Examples 1 to 30, further configured as claimed in any one of the following claims.

[0121] Example 32 is configured as any one of Examples 1 to 31, wherein the parameter representing the geometry of the sputtering target comprises or consists of a mechanical parameter, e.g., a weight of the sputtering target.

[0122] Example 33 is configured as any one of Examples 1 to 32, wherein the parameter representing the geometry of the sputtering target comprises or consists of a geometric parameter (e.g., geometric property of the sputtering target), e.g., an extent (e.g., diameter) of the sputtering target.

[0123] Example 34 is configured as any one of Examples 1 to 33, wherein the parameter representing the geometry of the sputtering target is at least (eg only) a function of the geometry of the sputtering target.

[0124] Example 35 is configured as any one of Examples 1 to 34, wherein the parameter representing the geometry of the sputtering target is independent of a capacitive coupling of the sputtering target to the coupling electrodes, e.g., of a capacitance provided between the sputtering target and each of the coupling electrodes.

[0125] Example 36 is configured as any one of Examples 1 to 35, wherein the parameter representing the geometry of the sputtering target is independent of the position of the plurality of coupling electrodes relative to each other and / or relative to the rotation axis.

[0126] Example 37 is configured as any one of Examples 1 to 36, wherein the parameter representing the geometry of the sputtering target is independent of a distance of each of the coupling electrodes from the rotation axis.

Claims

Patent claims 1. Coating device (100), comprising: • a bearing device (130) which provides a rotation axis (131) and is configured to set a tubular sputtering target (10) mounted by means of the bearing device (130) into a rotational movement about the rotation axis (131); • several movably mounted coupling electrodes (110) which are arranged one behind the other in a row along the rotation axis (131) for coupling an alternating voltage into the sputtering target (10); and • a positioning device (120) which is configured to influence a position of the plurality of coupling electrodes (110) relative to one another and / or relative to the rotation axis (131) depending on a parameter which represents a geometry of the sputtering target (10).

2. Coating device (100) according to claim 1, further comprising: • a circuit (140) which electrically couples the plurality of coupling electrodes (110) to one another and is configured to couple the alternating voltage provided to the circuit (140) into the sputtering target (10) in phase by means of the coupling electrodes (110); and • wherein the circuit (140) preferably comprises an electrical actuator (142) which is configured to influence an impedance and / or capacitance by means of which two of the plurality of coupling electrodes are coupled to one another.

3. Coating device (100) according to claim 1 or 2, • wherein the positioning device (120) is configured to influence a position of each coupling electrode of the plurality of coupling electrodes (110) such that a distance (120t) of the coupling electrode from the sputtering target (10) satisfies a criterion; and • the criterion is preferably fulfilled if the distance (120t) is smaller than a dark field distance.

4. Coating device (100) according to one of claims 1 to 3, wherein the positioning device (120) has, for each coupling electrode of the coupling electrodes (110), a support wheel which is coupled to the coupling electrode for supporting the coupling electrode on the sputtering target (10), preferably such that the position of the plurality of coupling electrodes (110) is a function of the geometry of the sputtering target (10).

5. Coating device (100) according to claim 4, • wherein the support wheel is configured to galvanically separate the coupling electrode from the sputtering target (10); and / or • the support wheel is dielectric.

6. Coating device (100) according to one of claims 1 to 5, wherein the parameter comprises a spatial distribution of the diameter of the sputtering target (10).

7. Coating device (100) according to one of claims 1 to 6, wherein the bearing device (130) has a magnet system (132), wherein the axis of rotation (131) is arranged between the magnet system (132) and the plurality of coupling electrodes (110).

8. Coating device (100) according to one of claims 1 to 7, further comprising: • an AC voltage source for providing the AC voltage; • wherein the alternating voltage source is preferably configured to provide the alternating voltage at a frequency in a range of approximately 1 megahertz to approximately 50 megahertz, preferably in a range of approximately 10 megahertz to approximately 15 megahertz.

9. Coating device (100) according to one of claims 1 to 8, wherein the bearing device (130) is further configured to supply the sputtering target (10) with a cooling fluid.

10. Coating device (100) according to one of claims 1 to 9, • wherein each of the coupling electrodes (110) has a concave surface facing the rotation axis (131), and / or • wherein an angular enclosure of each of the coupling electrodes (110) with respect to the axis of rotation (131) is greater than 100 degrees.

11. Coating device (100) according to one of claims 1 to 10, wherein at least one coupling electrode of the plurality of coupling electrodes (110) is arranged per meter along the rotation axis (131).

12. Coating device (100) according to one of claims 1 to 11, • wherein the storage device (130) is configured to store the sputtering target (10) which has an extension along the rotation axis (131) of more than 2 meters; and / or • wherein the bearing device (130) has two end blocks for rotatably supporting the sputtering target (10), wherein a distance (120t) between the two end blocks is greater than 2 meters.

13. Coating device (100) according to one of claims 1 to 12, further comprising: the tubular sputtering target (10).

14. Method, preferably for operating the coating device (100) according to one of claims 1 to 13, the method comprising: • Coupling an alternating voltage into a tubular sputtering target (10) by means of a plurality of movably mounted coupling electrodes (110) which are arranged one behind the other in a row along a rotational axis (131) of the sputtering target (10), for electrically supplying a plasma to which the sputtering target (10) is exposed; • Changing a position of the plurality of coupling electrodes (110) relative to one another and / or to the rotational axis (131) depending on a parameter representing a geometry of the sputtering target (10), preferably when the sputtering target (10) is exposed to the plasma and / or is set in a rotational movement.

15. Using a plurality of movably mounted coupling electrodes (110) which are arranged along a rotational axis (131) of a sputtering target (10) are arranged one behind the other in a row and whose position relative to one another and / or to the axis of rotation (131) is changed depending on a parameter which represents a geometry of the sputtering target (10), for coupling an alternating voltage into the sputtering target (10), preferably when the sputtering target (10) is exposed to a plasma and / or is set in a rotational movement.

Images