Sputter deposition source, magnetron sputter cathode, and method for depositing material on a substrate.

Abstract

A sputter deposition source (200) for depositing material on a substrate (10) is described. The sputter deposition source includes an array (210) of magnetron sputter cathodes arranged in a row to coat the substrate (10) in a deposition region (30) in front of the array (210). At least one magnetron sputter cathode (100) of the array (210) includes a first rotatable target (110) rotatable about a first axis of rotation (A1) and a first magnet assembly (120) disposed within the first rotatable target (110) and configured to provide a closed plasma racetrack (P) on a surface of the first rotatable target, the plasma racetrack (P) extending along the first axis of rotation (A1) at a first side and a second side of the at least one magnetron sputter cathode (100). A magnetron sputter cathode for a sputter deposition source and a method for depositing material on a substrate are further described.

Description

[Technical Field]

[0001] Embodiments of this disclosure relate to substrate coating by sputtering. Embodiments particularly relate to a sputtering deposition source for coating a substrate with a material, a magnetron sputtering cathode that can be used in the sputtering deposition source, and a method for depositing a material on a substrate by sputtering. Embodiments described herein relate particularly to the deposition of a material on a sensitive substrate by sputtering. [Background technology]

[0002] Forming thin layers on a substrate with high layer uniformity is a relevant problem in many technological fields. Sputtering is a suitable process for uniformly depositing material on a substrate, and it has been developed as a valuable method in various manufacturing fields, such as in the manufacture of displays. During sputtering, atoms are ejected from the surface of the sputtering target by collisions with the energetic particles of the plasma. The ejected atoms propagate toward the substrate and adhere there, and as a result, a layer of sputtered material can be formed on the substrate.

[0003] However, sputtering can result in collisions between the substrate and energetic particles such as energetic plasma particles (electrons and / or ions), which can have adverse effects on the substrate. Specifically, sputtering using energetic plasma can have unfavorable effects on the properties of any upper layers, particularly sensitive films, that may be located on the substrate. The adverse effects of sputtering on sensitive substrates can be mitigated by using a cathode that provides a plasma confinement region that is not directed directly towards the substrate. "Facing-target sputtering (FTS)" systems with planar targets have been devised for this purpose.

[0004] In FTS systems, instead of directing particles towards the substrate, flat targets face each other, resulting in a reduced impact effect on the substrate. However, conventional FTS systems have limited plasma stability, compromising their suitability for mass production. Furthermore, FTS systems are typically associated with reduced deposition rates and low material utilization, leading to low productivity and a risk of substrate surface contamination.

[0005] From the above perspective, it would be beneficial to provide improved apparatus and methods for depositing material by sputtering on a substrate, particularly on a substrate sensitive to collisions with energetic particles. Specifically, it would be beneficial to provide a sputtering deposition source and a magnetron sputtering cathode that enable coating of sensitive substrates by sputtering with improved material utilization and improved deposited layer quality. [Overview of the Initiative]

[0006] In light of the foregoing, a sputtering deposition source, a magnetron sputtering cathode, and a method for depositing material on a substrate are provided according to the independent claims. Further embodiments, advantages, and beneficial features are evident from the dependent claims, this specification, and the accompanying drawings.

[0007] According to one embodiment, a sputter deposition source is provided. The sputter deposition source includes an array of magnetron sputter cathodes arranged in a row to cover a substrate placed in a deposition region on the front side of the array. At least one magnetron sputter cathode of the array comprises a first rotating target rotatable about a first rotation axis and a first magnet assembly disposed within the first rotating target and configured to provide a closed plasma race track on the surface of the first rotating target, the closed plasma race track extending along the first rotation axis at a first side and at a second side of at least one magnetron sputter cathode different from the first side.

[0008] In some embodiments, the array may include a plurality of magnetron sputter cathodes, each having a specified feature on at least one of the magnetron sputter cathodes. Specifically, the first and second sides of a magnetron sputter cathode may be sides facing the longitudinal direction of the array, i.e., toward each adjacent magnetron sputter cathode in the array. When the plasma confinement region is directed toward adjacent magnetron sputter cathodes rather than toward the substrate, the risk of substrate damage due to particle collisions can be reduced.

[0009] In one embodiment, a magnetron sputter cathode is provided for use in any of the sputter deposition sources described herein. The magnetron sputter cathode includes a rotating target rotatable around a rotation axis, and a magnetron assembly disposed within the rotating target. The magnetron assembly includes a first magnet having a first polarity pole oriented radially outward, and a second magnet having a second polarity pole oriented radially outward, wherein the first and second magnets extend adjacent to each other along a closed path for generating a closed plasma racetrack on the surface of the rotating target, with a first plasma confinement region extending parallel to the rotation axis on a first side of the magnetron sputter cathode and a second plasma confinement region extending parallel to the rotation axis on a second side of the magnetron sputter cathode, distinct from the first side.

[0010] In particular, the first and second sides of the magnetron sputter cathode may be essentially opposite sides. Specifically, the first side may face the first adjacent magnetron sputter cathode, and the second side may face the second adjacent magnetron sputter cathode, and the magnetron sputter cathode, as well as the first and second adjacent magnetron sputter cathodes, may belong to an array of magnetron sputter cathodes arranged in a row.

[0011] In one embodiment, a method is provided for depositing a material on a substrate using a sputter deposition source according to any embodiment described herein. The method includes sputtering the material from at least one magnetron sputter cathode having a first magnet assembly positioned within a first rotating target that rotates around a first axis of rotation, the first magnet assembly providing a closed plasma racetrack on the surface of the first rotating target, with a first plasma confinement region extending parallel to the first axis of rotation on a first side of at least one magnetron sputter cathode and a second plasma confinement region extending parallel to the first axis of rotation on a second side of at least one magnetron sputter cathode, distinct from the first side.

[0012] This disclosure is understood to encompass apparatus and systems for performing the disclosed methods, including apparatus parts for performing each described embodiment of the method. Embodiments of the method may be performed, for example, by hardware components, by a computer programmed with appropriate software, or by any combination of the two. This disclosure is also understood to encompass methods for operating the described apparatus and systems. Methods for operating the described apparatus and systems include embodiments of methods for performing all functions of each apparatus or system. This disclosure is understood to encompass products manufactured according to any of the described deposition methods. In particular, coated substrates are provided that are manufactured according to any of the methods described herein and / or using any of the sputter deposition sources described herein.

[0013] To allow for a detailed understanding of the features listed above, a more specific description of the subject matter, briefly summarized above, is provided below with reference to embodiments. The accompanying drawings are relevant to the embodiments and are also described below. [Brief explanation of the drawing]

[0014] [Figure 1]This is a schematic cross-sectional view of a sputtering deposit source according to an embodiment described herein. [Figure 2(a)] This is a schematic diagram of the first side view of a magnetron sputter cathode according to an embodiment described herein. [Figure 2(b)] This is a schematic diagram of the front surface of a magnetron sputter cathode according to an embodiment described herein. [Figure 2(c)] This is a schematic diagram of a second side view of a magnetron sputter cathode according to an embodiment described herein. [Figure 2(d)] This is a schematic cross-sectional view of a magnetron sputter cathode according to an embodiment described herein. [Figure 2(e)] This is a schematic cross-sectional view of the magnet assembly of a magnetron sputter cathode. [Figure 3] This is a schematic front view of a sputter deposition source according to an embodiment described herein. [Figure 4(a)] This is a schematic diagram of the first side view of a magnetron sputter cathode according to an embodiment described herein. [Figure 4(b)] This is a schematic diagram of the front surface of a magnetron sputter cathode according to an embodiment described herein. [Figure 4(c)] This is a schematic diagram of a second side view of a magnetron sputter cathode according to an embodiment described herein. [Figure 4(d)] This is a schematic cross-sectional view of a magnetron sputter cathode according to an embodiment described herein. [Figure 5] This is a schematic front view of a sputter deposition source according to an embodiment described herein. [Figure 6A] This is a schematic cross-sectional view of a sputtering deposit source according to an embodiment described herein. [Figure 6B] This is a schematic cross-sectional view of a sputtering deposit source according to an embodiment described herein. [Figure 7] This is a schematic cross-sectional view of a sputtering deposit source according to an embodiment described herein. [Figure 8] It is a schematic cross-sectional view of a sputter deposition source according to an embodiment described in this specification. [Figure 9] It is a flowchart illustrating a method of depositing a material on a substrate according to an embodiment described in this specification.

Embodiments for Carrying Out the Invention

[0015] Hereinafter, various embodiments are referred to in detail, and one or more examples of the embodiments are illustrated in the figures. In the following description of the drawings, the same reference numerals refer to the same components. Generally, only the differences with respect to the individual embodiments are described. Each example is provided for illustration and not meant to be limiting. Further, features illustrated or described as part of one embodiment can be used in or in combination with other embodiments to further bring about additional embodiments. The description is intended to include such modifications and variations.

[0016] FIG. 1 shows a sputter deposition source 200 for depositing a material on a substrate 10 according to an embodiment described in this specification. The sputter deposition source 200 includes an array 210 of magnetron sputter cathodes arranged in a row to cover the substrate 10 disposed in a deposition region 30 in front of the array 210 of magnetron sputter cathodes. The sputter deposition source 200 can be disposed within a vacuum deposition chamber 201 of a sputter deposition system.

[0017] The sputter deposition source 200 can be usefully used in an inline sputter deposition system in which the substrate 10 is continuously moved past the sputter deposition source 200 through the deposition region 30, particularly at an essentially constant substrate speed, in the substrate transport direction (e.g., from left to right in Figure 1) ("dynamic coating"). Alternatively, the substrate may remain stationary during deposition ("static coating"). The sputter deposition source 200 can also be used in a sputter deposition system in which the substrate 10 is moved in a reciprocating manner in two opposite directions within the deposition region 30 (e.g., to the right and to the left in Figure 1 in a oscillating motion), changing its direction of movement several times, which is also referred to herein as "substrate oscillating" or "substrate sweeping".

[0018] As used herein, the “front” or “front side” of the array 210 of magnetron sputter cathodes, or of one magnetron sputter cathode, refers to the side on which the substrate 10 is positioned during sputter deposition. The area in front of the array 210 where sputter deposition onto the substrate 10 occurs is referred herein to as the deposition area 30. The “back” or “rear side” of the array 210 of magnetron sputter cathodes, or of one magnetron sputter cathode, refers to the side opposite to the front side, i.e., the side facing away from the substrate 10 during sputter deposition. The “lateral side” of a magnetron sputter cathode in an array can be understood as the side facing, for example, an adjacent magnetron sputter cathode in the longitudinal direction L of the array. An array of magnetron sputter cathodes may be a linear array in which the magnetron sputter cathodes are arranged sequentially in a linear column direction, for example, at equal distances from each other, as schematically depicted in Figure 1. An array of magnetron sputter cathodes can also be a curved array in which the magnetron cathodes are arranged along a curve, for example, in an arc.

[0019] The array 210 of magnetron sputter cathodes comprises a plurality of magnetron sputter cathodes, in particular, 3, 4, 5, 6 or more, or 10 or more magnetron sputter cathodes. At least one magnetron sputter cathode 100 of the array is described in further detail below. It should be understood that the array 210 typically comprises several magnetron sputter cathodes arranged adjacent to one another, each having the features of at least one magnetron sputter cathode 100 as described herein. The sputter deposition source 200 in Figure 1 exemplifies a total of four magnetron sputter cathodes arranged in a row, with the inner cathodes (i.e., all except the first end cathode 203 and the second end cathode 204) being configured according to at least one magnetron sputter cathode 100. Although only two inner cathodes are shown exemplarily in Figure 1, three or more inner cathodes may be provided between the first end cathode 203 and the second end cathode 204.

[0020] At least one magnetron sputter cathode 100 of array 210 includes a first rotating target 110 rotatable around a first rotation axis A1, and a first magnet assembly 120 positioned within the first rotating target 110 and configured to provide a closed plasma race track P on the surface of the first rotating target. As described above, array 210 may include at least one magnetron sputter cathode 100, for example, a plurality of magnetron sputter cathodes configured according to 2, 4, 6, 10 or more magnetron sputter cathodes positioned adjacent to one another, in particular between two end cathodes (e.g., the first end cathode 203 and the second end cathode 204 as depicted in Figure 1).

[0021] A “magnetron sputter cathode” can be understood as a sputter cathode configured for magnetron sputtering, including a magnetic assembly for confining the sputtered plasma within a plasma confinement region during sputtering. A magnetron sputter cathode as described herein may include a rotating target configured to provide a target material to be deposited on a substrate and which can be set to a predetermined potential. The rotating target may be an essentially cylindrical or dogbone-shaped target that can rotate around a rotation axis. Rotation of the rotating target around the rotation axis during sputtering ensures more uniform sputtering of the target surface and, therefore, more uniform ablation and consumption of the target material on the rotating target, and as a result, the material utilization rate may be improved compared to a planar target. In particular, as used herein, a “rotating target” may not necessarily include the target material to be deposited on the substrate, but may be a rotatable target backing tube or rotatable target material holder on which the actual target material (typically a cylindrical material sleeve consumed during sputtering) will be mounted. The rotating target can be set to a predetermined potential for plasma ignition and maintenance, and can rotate around its axis of rotation together with the actual target material.

[0022] Magnetron sputtering is particularly advantageous in that it can provide high deposition rates because the sputtered plasma is confined by a magnetic assembly to a plasma confinement region adjacent to the surface of the rotating target to be sputtered. The magnetic assembly is positioned within the rotating target. By positioning the magnetic assembly within the rotating target, i.e., inside a cylindrical or dogbone-shaped target, free electrons on the target surface are forced to move within the magnetic field and cannot escape. This increases the likelihood of ionizing gas molecules typically by orders of magnitude, and as a result, the deposition rate can be significantly increased.

[0023] Sputtering can be used in the production of displays. More specifically, sputtering can be used for metallization, such as the creation of electrodes or buses. Sputtering is also used for the production of thin-film transistors (TFTs). It can also be used for the creation of transparent and conductive oxide layers, such as ITO (indium tin oxide) layers. Sputtering can also be used for the production of thin-film solar cells. Generally, thin-film solar cells consist of a back contact, an absorption layer, and a transparent and conductive oxide layer (TCO). Typically, the back contact and TCO layers are produced by sputtering, while the absorption layer is typically fabricated by a chemical vapor deposition process. In some embodiments, semiconductor substrates, such as wafers, can be coated by magnetron sputtering.

[0024] As used herein, the term “substrate” encompasses both non-flexible substrates, such as wafers or glass plates, and flexible substrates, such as webs and foils, and optionally includes one or more layers or materials previously deposited thereon. In some embodiments, the substrate is a non-flexible substrate, such as a glass plate, used, for example, in the production of solar cells. The term substrate particularly encompasses substrates having sensitive top layers, such as organic material layers or OLED layer stacks or patterns, on which further materials are deposited by sputtering, with a reduced risk of damaging the sensitive top layers.

[0025] A typical magnetic assembly used to confine sputtered plasma to a predetermined region is configured to provide a closed plasma racetrack. A “closed” plasma racetrack extends along a loop or track on the surface of a rotating target, so that electrons of the plasma cannot escape and, because the racetrack is closed, cannot leave the plasma racetrack at the open end of the plasma confinement region. More specifically, the magnetic assembly generates a magnetic field with magnetic field lines, around which free electrons of the plasma undergo helical circular motion, while remaining within the region defined by the plasma racetrack because the plasma racetrack is closed. The form of the closed plasma racetrack on the target surface is defined by a loop, along which the magnets of the magnetic assembly extend inward on the rotating target.

[0026] Conventional magnet assemblies are typically configured to provide a closed plasma race track on a single side of a magnetron sputter cathode, which is typically directed directly toward the substrate. Alternatively, two separate closed plasma race tracks may be generated on two opposite sides of the magnetron sputter cathode, for example, for double-sided sputtering, directed toward two different substrates. In the latter case, each of the two separate closed plasma race tracks is located on only one single side of the magnetron sputter cathode. Such a magnet assembly typically includes a first magnet surrounded by a second magnet located at close range, resulting in a closed plasma race track (a so-called "double race track") being generated in the region in front of the magnet assembly, and is also referred to herein as a "front-sputtered magnet assembly." While front-sputtered magnet assemblies can enable high deposition rates, they carry the risk that sensitive substrates may be adversely affected due to the high energy input per unit area toward the substrate.

[0027] The risk of damaging the sensitive substrate layer can be reduced by using a “front sputtering magnet assembly” positioned within a rotating target that faces the adjacent magnetron sputtering cathode rather than directly towards the substrate. Such an arrangement may also be referred to as “rotating-opposed-target sputtering (RFTS).” This arrangement reduces the proportion of target material atoms that propagate toward the substrate during sputtering. However, because the plasma racetrack generated by the front sputtering magnet assembly on one single (lateral) side of the magnetron sputtering cathode has a substantial angular extension around the rotation axis (e.g., 10° to 25°), target material atoms knocked out of the target propagate over a wide angular range around the magnetron sputtering cathode. Consequently, a considerable amount of target material accumulates on the vacuum chamber walls or material shield and is therefore wasted. Material utilization and productivity are reduced.

[0028] Embodiments described herein relate to specific shapes and designs of magnet assemblies in a rotating target that overcome the above-described problems. Specifically, the sensitive substrate may be further coated with a reduced risk of substrate damage, while simultaneously achieving increased material utilization. The magnet assembly according to the embodiments described herein is configured to provide a closed plasma race track on the surface of a rotating target, the closed plasma race track extending along the axis of rotation on a first side and on a second side of at least one magnetron sputter cathode distinct from the first side. In other words, a single closed plasma race track extending parallel to the axis of rotation is generated by the magnet assembly on different sides of at least one magnetron sputter cathode, in particular on two opposite sides which may optionally face the longitudinal direction L of the array of magnetron sputter cathodes.

[0029] In particular, a single closed plasma racetrack has a first plasma confinement region 31 extending parallel to the axis of rotation and facing a first adjacent magnetron sputter cathode on a first side of at least one magnetron sputter cathode, and a second plasma confinement region 32 extending parallel to the axis of rotation and facing a second adjacent magnetron sputter cathode on a second side of at least one magnetron sputter cathode opposite the first side. Such a racetrack may also be referred to as a "double-sided single racetrack" because the single closed racetrack extends across two different sides of the rotating target.

[0030] Referring back to Figure 1, the first magnet assembly 120 of at least one magnetron sputter cathode 100 is positioned inside the first rotating target 110 and is configured to provide a closed plasma race track P on the surface of the first rotating target 110, extending along the first rotation axis A1 on the first and second sides of the at least one magnetron sputter cathode 100. Specifically, the closed plasma race track P includes a first plasma confinement region 31 extending parallel to the first rotation axis A1 on the first side of the at least one magnetron sputter cathode, and a second plasma confinement region 32 extending parallel to the first rotation axis A1 on a second side of the at least one magnetron sputter cathode, distinct from the first side. Thus, the closed plasma race track P is a “double-sided single race track” as specified above.

[0031] Further details of the first magnet assembly 120 are shown in Figure 2. Figure 2(a) is a side view of the at least one magnetron sputter cathode 100 from a first side; Figure 2(b) is a front view of the at least one magnetron sputter cathode 100 as seen from the deposition region 30; Figure 2(c) is a side view of the at least one magnetron sputter cathode 100 from a second side opposite the first side; and Figure 2(d) is a cross-sectional view of the at least one magnetron sputter cathode 100 through its central cross section.

[0032] At least one magnetron sputter cathode 100 includes a first rotating target 110 that is rotatable around a first rotation axis A1, and a first magnet assembly 120 positioned inside the first rotating target 110. The first rotating target 110 may have an essentially cylindrical shape and is configured to provide a target material to be deposited on a substrate. The first magnet assembly 120 is formed to generate a closed plasma race track P on the surface of the first rotating target 110 during sputtering, the closed plasma race track P extending along the first rotation axis A1 on a first side and on at least one second side of the magnetron sputter cathode 100 distinct from the first side.

[0033] In particular, the first and second sides of at least one magnetron sputter cathode 100 are oriented in two different directions surrounding a first angle (a1) of 30° or more, especially 90° or more, even more particularly 135° or more, or even about 180° with respect to the first axis of rotation A1. In the latter case, the first and second sides are opposite sides of at least one magnetron sputter cathode. Thus, the closed plasma racetrack P may have a first plasma confinement region 31 and a second plasma confinement region 32 on the opposite side of at least one magnetron sputter cathode 100 in the circumferential direction.

[0034] In some embodiments, the first and second sides of at least one magnetron sputter cathode 100 are two opposite sides facing the longitudinal direction L of the array 210 of magnetron sputter cathodes, respectively. Thus, the closed plasma racetrack P may have a first plasma confinement region 31 facing the first adjacent magnetron sputter cathode of the array 210, and a second plasma confinement region 32 facing the second adjacent magnetron sputter cathode of the array located on the opposite side, as schematically depicted in Figure 1.

[0035] Because the first plasma confinement region 31 and the second plasma confinement region 32 of the closed plasma racetrack P are circumferentially positioned on different sides of at least one magnetron sputter cathode, a reduced amount of plasma particles (per unit area) strike the substrate, resulting in a "softer" sputtering process. When the first plasma confinement region 31 and the second plasma confinement region 32 are positioned adjacent to at least one magnetron sputter cathode 100 in the longitudinal direction L of the array 210, a significant portion of the target material atoms emitted from the first rotating target 110 propagate toward the adjacent magnetron sputter cathode in the array and adhere there (see arrows 901 and 902 in Figure 1). Target material atoms adhering to the adjacent magnetron sputter cathode can later be emitted from the adjacent magnetron sputter cathode toward the substrate, and are not lost or wasted. Some of the emitted target material atoms propagate toward the substrate 10 (see arrow 903 in Figure 1), where they form a layer, possibly at a reduced deposition rate ("stray coating"). Because the plasma is not directed directly toward the substrate, the risk of damaging the substrate with charged plasma particles is reduced.

[0036] Furthermore, because the closed plasma racetrack P extends along the first rotation axis A1 to two different sides of at least one magnetron sputter cathode 100, the angular extensions of the first plasma confinement region 31 and the second plasma confinement region 32 are relatively small (i.e., a "single" racetrack extending across different target sides compared to a "double" racetrack on a single target side), and as a result, stray covering in undesirable directions, such as towards the rear of the array, can be reduced. Figure 1 schematically illustrates that the plasma confinement region generated by a laterally inward-facing "front sputter magnet assembly" has a broader angular extension, promoting stray covering in undesirable directions (see arrow 905 in Figure 1).

[0037] A magnetron sputter cathode of array 210 positioned adjacent to at least one magnetron sputter cathode 100 is also referred to herein as a second magnetron sputter cathode 202 and is depicted in Figure 1 to the right of at least one magnetron sputter cathode 100. The second magnetron sputter cathode 202 includes a second rotating target rotatable about a second rotation axis A2 and a second magnet assembly 222 positioned within the second rotating target and configured to provide a closed plasma racetrack on the surface of the second rotating target, the closed plasma racetrack extending along the second rotation axis A2 on first and second sides of the second magnetron sputter cathode 202. Specifically, the second magnet assembly 222 may be configured according to the first magnet assembly 120 (apart from an optional magnetic pole reversal as depicted in Figure 1).

[0038] As depicted in Figure 1, the first side of at least one magnetron sputter cathode 100 may face the second magnetron sputter cathode 202, and the second side of the second magnetron sputter cathode 202 may face at least one magnetron sputter cathode 100. Such an arrangement has the beneficial effect that many of the target material atoms emitted from the rotating target propagate toward each adjacent magnetron sputter cathode, adhere to them, and are therefore not wasted. Furthermore, the plasma is not directed directly toward the substrate but is concentrated in the region between the adjacent magnetron sputter cathodes.

[0039] As illustrated in detail in Figures 2(d) and 2(e), the first magnet assembly 120 may include a first magnet 121 having a first polarity pole (e.g., the south pole illustrated in the figure by the first shaded type) oriented radially outward, and a second magnet 122 having a second magnetic pole (e.g., the north pole illustrated in the figure by the second shaded type) oriented radially outward. The first magnet 121 and the second magnet 122 extend adjacent to each other along a closed path inside the first rotating target 110 for generating a closed plasma racetrack P on the surface of the first rotating target.

[0040] In other words, both the first magnet 121 and the second magnet 122 extend along the closed circuit within the first rotating target 110, the first magnet 121 having a first polar magnetic pole oriented radially outward, and the second magnet 122 having a second magnetic pole oriented radially outward along the closed circuit. The first magnet 121 and the second magnet 122 extend adjacent to each other along the closed circuit, for example, with an essentially constant gap between them, as a result providing an essentially uniform plasma confinement region along the closed circuit.

[0041] Figure 2(e) is a cross-sectional view of the first magnet assembly 120 in a cross-section perpendicular to the extension of the loop. The south pole of the first magnet 121 is oriented radially outward (i.e., toward the first rotating target 110), and the north pole of the second magnet 122 is adjacent to it and oriented radially outward (i.e., toward the first rotating target 110), as a result a plasma confinement region (here, the second plasma confinement region 32) is generated by the resulting magnetic field lines on the surface of the first rotating target 110.

[0042] As illustrated in detail in Figure 2(b), the loop may include two linear track regions, each extending parallel to the first rotation axis A1. Along each of the linear track regions, the first magnet 121 and the second magnet 122 are oriented radially inward and outward to provide a first plasma confinement region 31 and a second plasma confinement region 32 on different sides of the first rotating target. The two linear track regions may extend axially over 60% or more, particularly 70% or more, of the axial dimension of the first rotating target 110, so that the target material on most of the surface of the first rotating target is sputtered by the generated plasma. The loop may further include two curved tracks connecting the two linear track regions at two opposite axial ends of at least one magnetron sputter cathode 100.

[0043] In some embodiments, the first magnet assembly 120 is configured to provide a closed plasma racetrack P including a first plasma confinement region 31 extending parallel to a first rotation axis A1 on a first side of at least one magnetron sputter cathode, a second plasma confinement region 32 extending parallel to the first rotation axis A1 on a second side of at least one magnetron sputter cathode different from the first side, a first curved plasma confinement region 33 connecting the first and second plasma confinement regions at a first axial end portion of at least one magnetron sputter cathode, and a second curved plasma confinement region 34 connecting the first and second plasma confinement regions at a second axial end portion of at least one magnetron sputter cathode.

[0044] In embodiments that can be combined with other embodiments described herein, the axial direction of at least one magnetron sputter cathode 100 (and the axial direction of the other magnetron sputter cathodes in the array) may be essentially perpendicular. Thus, the first curved plasma confinement region 33 may connect the first plasma confinement region 31 and the second plasma confinement region 32 at the upper end of at least one magnetron sputter cathode, and the second curved plasma confinement region 34 may connect the first plasma confinement region 31 and the second plasma confinement region 32 at the lower end of at least one magnetron sputter cathode. In the front view, as depicted in Figure 2(b), the closed circuit of the first magnet assembly 120, and therefore the closed plasma racetrack P provided by the first magnet assembly, may essentially have the shape of a racetrack with two straight lines spaced apart from each other in the longitudinal direction L of the array and connected by two curves at the two axial ends of the rotating target.

[0045] In some embodiments, both the first curved plasma confinement region 33 and the second curved plasma confinement region 34 may extend to the front of the array. Specifically, the plasma racetrack may be closed at both the upper end of at least one magnetron sputter cathode and the lower end of at least one magnetron sputter cathode on the front side facing the deposition region 30. Since the plasma racetrack is oriented toward the substrate at the two axial end portions of the first rotating target 110, the sputter deposition rate from the two axial end portions of at least one magnetron sputter cathode to the substrate can be increased by such a configuration of the first magnet assembly 120. In some embodiments, the increased deposition rate to the substrate regions (e.g., upper and lower substrate edge regions) corresponding to the axial end portions of at least one magnetron sputter cathode may be beneficial.

[0046] In other embodiments, both the first curved plasma confinement region 33 and the second curved plasma confinement region 34 may extend to the rear side of the array opposite the front side. Specifically, the plasma racetrack may be closed at both the upper end of at least one magnetron sputter cathode and the lower end of at least one magnetron sputter cathode on the rear side, which is oriented away from the substrate during sputter deposition. The sputter deposition rate onto the substrate region corresponding to the two axial end portions of the magnetron sputter cathode can be reduced by such a configuration of the first magnet assembly 120. In some embodiments, the reduced deposition rate onto the substrate region corresponding to the axial end portions of at least one magnetron sputter cathode (e.g., the upper and lower substrate edge regions) may be beneficial.

[0047] As further shown in Figure 1, the array 210 may include a first end cathode 203 provided at a first end of the array 210 in the longitudinal direction L, and / or a second end cathode 204 provided at a second end of the array 210 in the longitudinal direction L. The first end cathode 203 and / or the second end cathode 204 may include a different magnet assembly from the magnet assembly of the inner magnetron sputter cathode of the array in order to prevent or reduce stray coating toward the wall of the vacuum deposition chamber 201 at the end of the array 210.

[0048] In particular, the first end cathode 203 may include a third magnet assembly configured to generate a closed plasma race track extending along one side of the first end cathode 203, specifically, the closed plasma race track facing toward the remaining magnetron sputter cathodes of array 210. In an embodiment, the third magnet assembly 223 may include a first magnet having a first polarity pole oriented radially outward, and a second magnet surrounding the first magnet, having a second polarity pole oriented radially outward, to generate a closed plasma race track. In the cross-sectional view of Figure 1, the second magnet is positioned two opposite sides of the centrally located first magnet. The third magnet assembly 223 may correspond to a front sputter magnet assembly oriented laterally toward an adjacent magnetron sputter cathode but not toward the deposition region 30.

[0049] Alternatively or additionally, the second end cathode 204 may include a fourth magnet assembly 224 configured to generate a closed plasma race track extending along one side of the second end cathode 204, in particular, the closed plasma race track facing toward the remaining magnetron sputter cathodes of array 210. The fourth magnet assembly 224 may include a first magnet having a first polarity pole oriented radially outward, and a second magnet having a second polarity pole oriented radially outward, surrounding the first magnet along one side of the second end cathode. In the cross-sectional view of Figure 1, the second magnet is located two opposite sides of the centrally located first magnet. The fourth magnet assembly 224 may correspond to a front sputter magnet assembly oriented laterally toward the adjacent magnetron sputter cathode but not toward the deposition region 30.

[0050] In some embodiments, four, six or more magnetron sputter cathodes, each having some or all the features of at least one magnetron sputter cathode 100, are arranged between a first end cathode 203 and a second end cathode 204. In particular, each of the magnetron sputter cathodes arranged between the first end cathode and the second end cathode may have a magnet assembly configured to provide a closed plasma racetrack having two plasma confinement regions that extend axially on two opposite sides in the longitudinal direction L of each magnetron sputter cathode.

[0051] In some embodiments, which may be combined with other embodiments described herein, a first shield 21 is positioned between at least one magnetron sputter cathode 100 and a deposition region 30, and / or a second shield 22 is positioned between a second magnetron sputter cathode 202 and a deposition region 30, so that a deposition window 20 is positioned between the first shield 21 and the second shield 22. The deposition window allows sputter deposition onto the substrate 10 from a plasma confinement region positioned between at least one cathode 100 and a second magnetron sputter cathode 202. In particular, each of the magnetron sputter cathodes of the array 210 may have its own shield positioned between the magnetron sputter cathode and the deposition region 30, so that a plurality of deposition windows are provided, each at a position corresponding to the region between the magnetron sputter cathodes.

[0052] Figure 3 shows a sputter deposition source with an array 410 of magnetron sputter cathodes arranged in a row in a front view. The array 410 includes a plurality of magnetron sputter cathodes 411 configured according to at least one magnetron sputter cathode 100 shown in Figure 2. Each magnetron sputter cathode includes a magnet assembly configured to generate a closed plasma racetrack extending in the respective axial directions at two opposite ends of each magnetron sputter cathode. The first and second plasma confinement regions are oriented toward each adjacent magnetron sputter cathode. The two curved plasma confinement regions at the axial ends of each cathode are located on the same side of the array, in particular, on the front side of the array facing the deposition region (or alternatively, on the rear side of the array facing away from the deposition region). The array 410 of magnetron sputter cathodes shown in Figure 3 enables the deposition of material onto the substrate at a moderately high deposition rate with reduced energy input into the substrate by charged particles, thereby reducing the risk of damage to the sensitive substrate surface. Optionally, one or two end cathodes, as described herein, may be added to the two opposite ends of array 410 (not shown in Figure 3).

[0053] Figures 4(a) to 4(d) are schematic diagrams of a magnetron sputter cathode 100' according to an embodiment described herein, which may replace at least one magnetron sputter cathode 100 shown in Figure 2 in any of the embodiments described herein. Figure 4(a) is a first side view, Figure 4(b) is a front view, Figure 4(c) is a second side view, and Figure 4(d) is a cross-sectional view of the central area of ​​the magnetron sputter cathode 100'. The magnetron sputter cathode 100' is similar to the at least one magnetron sputter cathode 100 described above, and therefore the above description can be referenced and will not be repeated here. Only the differences will be described.

[0054] The magnetron sputter cathode 100' includes a first rotating target 110 that is rotatable around a first rotation axis A1, and a first magnet assembly 120' positioned within the first rotating target 110. The first magnet assembly 120' includes a first magnet 121 having a first polar magnetic pole (e.g., a south pole) oriented radially outward, and a second magnet 122 having a second magnetic pole (e.g., a north pole) oriented radially outward. The first magnet 121 and the second magnet 122 extend adjacent to each other along a closed path for generating a closed plasma race track P' on the surface of the first rotating target, with the first plasma confinement region 31 extending parallel to the first rotation axis on the first side of the magnetron sputter cathode 100' and the second plasma confinement region 32 extending parallel to the first rotation axis A1 on a second side of the magnetron sputter cathode different from the first side (e.g., the opposite side).

[0055] The first curved plasma confinement region 33 connects the first plasma confinement region 31 and the second plasma confinement region 32 at the first axial end portion of the magnetron sputter cathode, and the second curved plasma confinement region 35 connects the first plasma confinement region 31 and the second plasma confinement region 32 at the second axial end portion of the magnetron sputter cathode. Unlike at least one magnetron sputter cathode 100 in Figure 2, the first curved plasma confinement region 33 may extend to the front side of the array (or alternatively, to the rear side of the array), and the second curved plasma confinement region 35 may extend to the rear side of the array (or alternatively, to the front side of the array). Thus, the closed plasma racetrack P' is oriented toward the deposition region 30 at one of the axial ends of the magnetron sputter cathode and with its back to the deposition region 30 at the other axial end of the magnetron sputter cathode. For example, the first curved plasma confinement region 33 may connect the first and second plasma confinement regions at the upper end of the magnetron sputter cathode on the front side of the array, and the second curved plasma confinement region 35 may connect the first and second plasma confinement regions at the lower end of the magnetron sputter cathode on the rear side of the array, or vice versa.

[0056] Specifically, the closed plasma race track P' may "turn" on the opposite side of the magnetron sputter cathode 100'. The side of the magnetron sputter cathode to which the closed plasma race track turns may differ between two adjacent magnetron sputter cathodes in the array, as schematically depicted in Figure 5. In particular, the closed plasma race track of at least one magnetron sputter cathode may include a first curved plasma confinement region in the upper axial end portion extending to the front of the array and a second curved plasma confinement region in the lower axial end portion extending to the rear of the array, while the closed plasma race track of a second magnetron sputter cathode adjacent to at least one magnetron sputter cathode may include a first curved plasma confinement region in the upper axial end portion extending to the rear of the array and a second curved plasma confinement region in the lower axial end portion extending to the front of the array. Optionally, additional magnetron sputter cathodes, each consisting of at least one sputter cathode and a second sputter cathode, can be arranged adjacent to one another in an alternating configuration, as schematically depicted in Figure 5.

[0057] Figure 5 shows a sputter deposition source with an array 420 of magnetron sputter cathodes arranged in a row in a front view. The array 420 includes a plurality of magnetron sputter cathodes configured according to the magnetron sputter cathode 100' shown in Figure 4, wherein adjacent magnetron sputter cathodes in the array have inverted magnet assemblies (i.e., the magnet assemblies of adjacent magnetron sputter cathodes are rotated 180° relative to each other around a rotation axis) so as to provide an alternating array of magnetron sputter cathodes. Each second magnetron sputter cathode 421 has a first curved plasma confinement region extending to the front of the array (located at the upper cathode end) and a second curved plasma confinement region extending to the rear of the array (located at the lower cathode end). The magnetron sputter cathodes 422, positioned between them, have a first curved plasma confinement region extending to the rear of the array (located at the upper cathode end) and a second curved plasma confinement region extending to the front of the array (located at the lower cathode end). Such an alternating arrangement of magnetron sputter cathodes can provide a sputtered deposit with more uniform upper and lower end portions, as it compensates for the potential inhomogeneity caused by the difference between the upper and lower curved plasma confinement regions.

[0058] As described above, end cathodes as described herein (not shown in Figure 5) may optionally be located at one or both ends of the array 420.

[0059] Figures 6A and 6B are schematic cross-sectional views of sputter deposition sources according to embodiments described herein. In the sputter deposition source 510 of Figure 6A, the magnet assemblies of two adjacent magnetron sputter cathodes are arranged "asymmetrically" with respect to each other. In the sputter deposition source 520 of Figure 6B, the magnet assemblies of two adjacent magnetron sputter cathodes are arranged "symmetrically" with respect to each other.

[0060] First, referring to Figure 6A, the first and second magnets of the first magnet assembly of at least one magnetron sputter cathode 511 are oriented toward the first and second magnets of the second magnet assembly of the second magnetron sputter cathode 512, which is positioned adjacent to at least one magnetron sputter cathode 511, and are positioned asymmetrically with respect to the first and second magnets of the second magnet assembly. "Asymmetrically positioned" can be understood as the first polar magnetic pole of the first magnet of the first magnet assembly of the first magnet assembly being oriented toward the second magnetic magnetic pole of the first magnet of the adjacent magnetron sputter cathode second magnet assembly, and the second magnetic magnetic pole of the second magnet of the first magnet assembly being oriented toward the first polar magnetic pole of the second magnet of the adjacent magnetron sputter cathode second magnet assembly. When the opposite poles of the magnetic assemblies of adjacent magnetron sputter cathodes are oriented toward each other, a larger plasma confinement region is generated between the magnetron sputter cathodes, or even a single continuous plasma confinement region extends between adjacent magnetron sputter cathodes. This results in a magnetic lensing effect that facilitates the divergence of charged particles away from the substrate, which can be beneficial for sputter deposition on sensitive substrates.

[0061] Some pairs of adjacent magnetron sputter cathodes in the array may have magnet assemblies that are arranged asymmetrically with respect to each other, as schematically depicted in Figure 6A.

[0062] Referring now to Figure 6B, the first and second magnets of the first magnet assembly of at least one magnetron sputter cathode 521 are oriented toward the first and second magnets of the second magnet assembly of the second magnetron sputter cathode 522, which is positioned adjacent to at least one magnetron sputter cathode 521, and are positioned symmetrically with respect to the first and second magnets of the second magnet assembly. "Symmetrically positioned" can be understood as the first polar magnetic pole of the first magnet of the first magnet assembly of the first magnet assembly being oriented toward the first magnetic magnetic pole of the first magnet of the adjacent magnetron sputter cathode's second magnet assembly, and the second magnetic magnetic pole of the second magnet of the first magnet assembly being oriented toward the second polar magnetic pole of the second magnet of the adjacent magnetron sputter cathode's second magnet assembly. When the same poles of the magnet assemblies of adjacent magnetron sputter cathodes are oriented toward each other, a smaller plasma confinement region is generated between the adjacent magnetron sputter cathodes, which may be useful in reducing the sputter deposition rate and / or further reducing the energy input into the substrate.

[0063] Some pairs of adjacent magnetron sputter cathodes in the array may each have magnet assemblies arranged symmetrically with respect to one another, as schematically depicted in Figure 6B.

[0064] Figure 7 is a schematic cross-sectional view of a sputter deposition source 600 according to an embodiment described herein, configured for use in a double-sided sputtering system that enables simultaneous or subsequent coating of two substrates on both sides of the sputter deposition source 600. The sputter deposition source 600 may be configured according to any of the embodiments described herein.

[0065] The sputter deposition source 600 is located within the vacuum deposition chamber 201. A deposition region 30 for covering the substrate 10 is located in front of the sputter deposition source 600, and a second deposition region 630 for covering the second substrate 11 is located on the rear side of the sputter deposition source 600, opposite the first side. Substrate transport tracks may extend through each of the two deposition regions.

[0066] At least one magnetron sputter cathode 100, or several magnetron sputter cathodes of the array 210 of magnetron sputter cathodes, include a magnet assembly configured to produce a closed “double-sided single racetrack” as described herein. The “double-sided single racetrack” of at least one magnetron sputter cathode 100 includes a first plasma confinement region 31 directed toward a first adjacent magnetron sputter cathode, and a second plasma confinement region 32 directed toward a second adjacent magnetron sputter cathode. Thus, target material atoms emitted from the rotating target by plasma particles can propagate both toward the deposition region 30 where the substrate 10 is located, and toward the second deposition region 630 where the second substrate 11 is located. Material utilization can be further increased as the reduced amount of target material atoms accumulates on the walls of the vacuum deposition chamber 201 or other material shields.

[0067] In some embodiments, which may be combined with other embodiments described herein, at least one magnetic lens 25 may be provided in the region between the sputter deposition source and the deposition region. The at least one magnetic lens 25 may be configured to deflect charged particles (such as electrons or ions in the plasma) away from the substrate, which may further soften the sputter deposition on the substrate. In some embodiments, multiple magnetic lenses may be provided, for example, in the region of a deposition window 20, which may each be provided between a shield positioned between the magnetron sputter cathode and the deposition region.

[0068] Figure 8 is a schematic cross-sectional view of a sputter deposition source 701 according to an embodiment described herein, which is configured for use in an inline deposition system 700, in which the substrate 10 is transported downstream D past the sputter deposition source 701, particularly in continuous linear motion, during sputter deposition.

[0069] The sputtering deposition source 701 includes an array 210 of magnetron sputtering cathodes arranged in a single row extending in the longitudinal direction L. The array 210 includes at least one magnetron sputtering cathode 100 as described herein, which includes a first magnet assembly 120 configured to generate a closed plasma racetrack extending on a first side and a second side of at least one magnetron sputtering cathode 100. The first side and the second side of the at least one magnetron sputtering cathode are oriented in two different directions surrounding a first angle a1 with respect to a first rotation axis A1. The first angle a1 may be 160° or greater, in particular about 180°. In particular, the first side and the second side are oriented toward two adjacent magnetron sputtering cathodes in the longitudinal direction L such that collisions between the substrate and energetic particles from the plasma are significantly reduced during sputtering deposition. Optionally, several magnetron sputter cathodes with magnet assemblies oriented in the longitudinal direction L of the array may be provided in the initial region of the array 210, as schematically depicted in Figure 8. Thus, the adverse effects of sputter deposition on the sensitive substrate layer can be reduced.

[0070] Once the initial sputtered deposition layer is formed on the sensitive substrate by the magnetron sputter cathode positioned in the initial area of ​​array 210, the magnets of the subsequent cathode magnet assembly may be further tilted toward the substrate, as the initial sputtered deposition layer can act as a protective film for portions deposited after the sputtered deposition layer. Tilting the magnet assembly toward the substrate increases not only the sputter deposition rate but also collisions of the substrate with energetic and potentially harmful plasma particles.

[0071] The second magnetron sputter cathode 202 may be positioned adjacent to at least one magnetron sputter cathode 100 in the downstream direction D. The first and second sides of the closed plasma racetrack of the second magnetron sputter cathode 202 may surround a second angle a2 smaller than the first angle a1. Specifically, the magnets of the second magnet assembly of the second magnetron sputter cathode 202 may be tilted toward the substrate compared to the magnets of the first magnet assembly of at least one magnetron sputter cathode 100. For example, the second angle a2 is less than 180°, e.g., 120° to 150°. The second magnetron sputter cathode 202 results in an increased deposition rate and increased particle collisions with the substrate compared to at least one magnetron sputter cathode 100, which may be acceptable since an initial sputtered film acting as protection has already been deposited on the sensitive layer of the substrate. Optionally, several second magnetron sputter cathodes 202 having a second angle a2 between the first and second sides may be arranged adjacent to each other downstream of at least one magnetron sputter cathode 100.

[0072] Optionally, the third magnetron sputter cathode 301 may be positioned downstream of the second sputter cathode 202 in the downstream direction D. The first and second sides of the closed plasma racetrack of the third magnetron sputter cathode 301 may surround a third angle a3 smaller than the first and second angles a1 and a2. Specifically, the magnets of the third magnet assembly of the third magnetron sputter cathode 301 may be tilted further toward the substrate compared to the magnets of the second magnet assembly of the second magnetron sputter cathode 202. For example, the third angle a3 may be less than 120°, for example, between 70° and 110°. The third magnetron sputter cathode 301 results in an increased deposition rate and increased particle collisions with the substrate compared to the second magnetron sputter cathode 202, which may be acceptable since the sputtered film has already been deposited on the sensitive layer of the substrate by the previous magnetron sputter cathodes in the array. Optionally, several third magnetron sputter cathodes 301 having a third angle a3 between the first and second sides may be arranged adjacent to each other downstream of the second magnetron sputter cathode 202.

[0073] Optionally, further magnetron sputter cathodes having magnet assemblies in which the magnets are further tilted toward the substrate, for example, at least one fourth magnetron sputter cathode 302 enclosing a fourth angle a4 (smaller than the third angle a3) between a first side and a second side, and at least one fifth magnetron sputter cathode 303 enclosing a fifth angle a5 (smaller than the fourth angle a4) between a first side and a second side, may be provided downstream of the third magnetron sputter cathode 301. The sputter deposition rate may be increased in steps in the downstream direction D so that the sputter deposition layer acts as protection for the sensitive substrate layer at the downstream location of the initial area of ​​the array.

[0074] In some embodiments that may be combined with other embodiments described herein, the array 210 further includes at least one front sputter cathode 304 located downstream of the second magnetron sputter cathode 202 (and downstream of any optional third, fourth, and fifth magnetron sputter cathodes). The front sputter cathode 304 includes a front sputter magnet assembly 310 configured to provide a closed plasma racetrack extending in one side of the front sputter cathode facing the deposition region 30. Some front sputter cathodes, for example, front sputter cathode 304 and front sputter cathode 305, may be located in the final region of the array 210 in the downstream direction. The front sputter cathode 304 results in a high deposition rate that may be acceptable because a protective layer is already formed on top of the sensitive substrate layer.

[0075] In some embodiments, which may be combined with other embodiments described herein, the magnet assembly of at least one magnetron sputter cathode may be movable to adjust the angle between a first side and a second side. In particular, the first angle a1 between the linear track areas of the magnet assembly may be adjusted, for example, using an actuator, in a range of 50° to 180°. This allows for the adaptation of the magnetron sputter cathode to the sensitivity of the substrate to be coated, to the deposition material to be deposited on the substrate, and / or to the sputter deposition process. In other embodiments, the position and arrangement of the magnet assembly inside the rotating target may be fixed.

[0076] In some embodiments, multiple shields, including a first shield 21 and a second shield 22, are positioned between the array 210 and the deposition area 30, and the deposition window 20 provided between two adjacent shields gradually increases in the downstream direction D. Specifically, the distance between adjacent shields is adapted to the respective inclination angles of the magnet assemblies of the associated magnetron sputter cathodes. Shields may not be positioned between the front sputter cathode and the deposition area 30.

[0077] In some embodiments, which may be combined with other embodiments described herein, the width and / or shape of the deposition window 20 between two adjacent shields may be adjustable. Thus, the deposition window 20 may be adjusted to the tilt angle of the magnet assembly of the associated magnetron sputter cathode. This allows for the adaptation of the sputter deposition source to substrates with varying levels of sensitivity.

[0078] Figure 9 is a flowchart illustrating a method for depositing material onto a substrate according to embodiments described herein.

[0079] In box 910, the material is sputtered from at least one magnetron sputter cathode having a first magnet assembly positioned within a first rotating target that rotates around a first axis of rotation. The first magnet assembly provides a closed plasma race track P on the surface of the first rotating target, with a first plasma confinement region extending parallel to the first axis of rotation on a first side of the first magnetron sputter cathode, and a second plasma confinement region extending parallel to the first axis of rotation on a second side of the first magnetron sputter cathode, distinct from the first side. The at least one magnetron sputter cathode may optionally be an inner magnetron sputter cathode of an array of magnetron sputter cathodes arranged in a row.

[0080] The first and second sides may be two opposite sides of at least one magnetron sputter cathode, the first side facing the first adjacent magnetron sputter cathode, and the second side facing the second adjacent magnetron sputter cathode of the array.

[0081] In box 920, the substrate is moved past the sputter deposition source in a continuous linear motion to coat the substrate with material. For example, the substrate may be coated in an in-line deposition system in which the substrate is moved past the sputter deposition source in a downstream direction D. The sputter deposition source may have several magnetron sputter cathodes arranged adjacent to each other in the downstream direction D. The first and second sides of at least one magnetron sputter cathode may face two different directions surrounding a first angle a1 with respect to a first axis of rotation. For example, the first angle may be about 180°.

[0082] Optionally, a second magnetron sputter cathode may be positioned downstream of at least one magnetron sputter cathode. The first and second sides of the second magnetron sputter cathode may face two different directions enclosing a second angle a2 smaller than the first angle with respect to the second axis of rotation of the second magnetron sputter cathode.

[0083] Optionally, a third magnetron sputter cathode may be positioned downstream of the second magnetron sputter cathode. The first and second sides of the third magnetron sputter cathode may face two different directions enclosing a third angle smaller than the first and second angles with respect to the third axis of rotation of the third magnetron sputter cathode.

[0084] Optionally, the front sputter cathode may be positioned downstream of the second (and optionally third) magnetron sputter cathode. The front sputter cathode is configured to provide a closed plasma racetrack extending along a single side of the front sputter cathode facing the deposition region.

[0085] In an alternative process, the substrate may be moved within the deposition region in a reciprocating manner, for example, between two deflection positions, particularly in a rocking or sweeping motion. In such a sputter deposition system, a plurality of magnetron sputter cathodes, configured according to at least one magnetron sputter cathode as described herein, may be arranged adjacent to one another, and particularly between two end cathodes. First and second plasma confinement regions may be arranged between two adjacent magnetron sputter cathodes, respectively, as shown in Figure 1, to obtain a "soft" sputter deposition on the substrate.

[0086] In some embodiments, the material deposited on the substrate forms a transparent conductive oxide film. For example, the material deposited on the substrate may include at least one of IZO, ITO, and IGZO. In some embodiments, the material includes a metal such as Ag.

[0087] The substrate may include a sensitive layer or pattern, particularly containing an organic or OLED material, which will be coated using a sputter deposition source as described herein.

[0088] The sputtering source can be configured for DC sputtering. In some embodiments, the sputtering source can be configured for pulsed DC sputtering.

[0089] In embodiments, the sputtering deposition source may be configured for sputtering transparent conductive oxide films. The system may be configured for the deposition of materials such as indium tin oxide (ITO), indium zinc oxide (IZO), indium gallium zinc oxide (IGZO), or MoN. In embodiments, the system may be configured for the deposition of metallic materials such as silver, magnesium silver (MgAg), aluminum, indium, indium tin (InSn), indium zinc (InZn), gallium, gallium zinc (GaZn), niobium, alkali metals (such as Li or Na), alkaline earth metals (such as Mg or Ca), yttrium, lanthanum, lanthanides (such as Ce, Nd, or Dy), and alloys of these materials. In embodiments, the system may be configured for the deposition of AlO x NbO x SiO x WO x ZrO x The sputtering deposition source may be configured for the deposition of metal oxide materials such as the following. The sputtering deposition source may be configured for the deposition of electrodes, in particular transparent electrodes in displays, especially OLED displays, liquid crystal displays, and touchscreens. More specifically, the system may be configured for the deposition of top contacts for top-emitting OLEDs. In embodiments, the system may be configured for the deposition of electrodes, in particular transparent electrodes in thin-film solar cells, photodiodes, and smart or switchable glass. The system may be configured for sputtering transparent dielectrics used as charge generation layers. The system may be configured for the deposition of materials such as molybdenum oxide (MoO), or transition metal oxides such as vanadium oxide (VO), tungsten oxide (WOx), zirconium oxide (ZrO), or lanthanum oxide (LaO). The system may be configured for sputtering transparent dielectrics used as light-enhancing layers such as silicon oxide (SiO), niobium oxide (NbO), titanium oxide (TiO), or tantalum oxide (TaO).

[0090] In an embodiment, the target material of the rotating target can be selected from the group consisting of silver, aluminum, silicon, tantalum, molybdenum, niobium, titanium, and copper. In particular, the target material can be selected from the group consisting of IZO, ITO, silver, IGZO, aluminum, silicon, NbO, titanium, zirconium, and tungsten. The sputter deposition source can be configured to deposit the material by a reactive sputter process. In the reactive sputter process, typically, an oxide of the target material is deposited. However, nitrides or oxynitrides can also be deposited as well.

[0091] The embodiments described herein can be utilized for Display PVD, i.e., sputter deposition onto large-area substrates for the display market. According to some embodiments, each carrier having a large-area substrate or a plurality of substrates can have a size of at least 0.67 m 2 Typically, the size is from about 0.67 m 2 (0.73 m × 0.92 m - Gen4.5) to about 8 m 2 More typically, from about 2 m 2 to about 9 m 2 or even up to 12 m 2 Typically, the substrate or carrier for which structures, devices, such as cathode assemblies, and methods according to the embodiments described herein are provided is a large-area substrate as described herein.

[0092] The feature of the closed plasma racetrack facing the adjacent magnetron sputter cathode offers the advantage of achieving "soft" sputter deposition. For example, collisions between the substrate and high-energy particles are reduced. Damage to the substrate, particularly the OLED coating on the substrate, can be mitigated. This is particularly advantageous with respect to deposition on sensitive substrates or layers, more specifically, on substrates with sensitive coatings. The "double-sided single racetrack" feature produced by the magnet assemblies described herein increases material utilization by reducing collisions between the substrate and high-energy particles, while simultaneously reducing the amount of target material atoms adhering to the vacuum chamber walls and other material shields.

[0093] While the above covers some embodiments, other embodiments and further embodiments can be conceived without departing from the basic scope of this disclosure. The scope is determined by the following claims.

Claims

1. A sputtering deposition source (200) comprising an array (210) of magnetron sputter cathodes, wherein the array (210) is arranged in a row to cover a substrate (10) in a deposition region (30) in front of the array (210), and at least one magnetron sputter cathode (100) of the array (210) is A first rotating target (110) that can rotate around a first axis of rotation (A1), A first magnet assembly (120) is disposed within the first rotating target (110) and configured to provide a closed plasma race track (P) on the surface of the first rotating target, wherein the closed plasma race track (P) extends along the first rotation axis (A1) on a first side and a second side opposite the first side of the at least one magnetron sputter cathode (100) and A sputter deposition source (200) is provided.

2. The sputter deposition source according to claim 1, wherein the first and second sides of the at least one magnetron sputter cathode (100) are two opposite sides facing the longitudinal direction (L) of the array (210).

3. The first magnet assembly (120) is, A first magnet (121) having a first polar magnetic pole directed radially outward, A second magnet (122) having a second polar magnetic pole oriented radially outward, and Equipped with, The sputtering deposition source according to claim 1, wherein the first magnet (121) and the second magnet (122) extend adjacent to each other along a closed path for generating the closed plasma race track (P) on the surface of the first rotating target.

4. The sputtering deposition source according to claim 1, wherein the closed plasma racetrack (P) includes a first plasma confinement region (31) extending parallel to the first rotation axis (A1) on the first side of the at least one magnetron sputter cathode, a second plasma confinement region (32) extending parallel to the first rotation axis (A1) on the second side of the at least one magnetron sputter cathode, different from the first side, a first curved plasma confinement region (33) connecting the first and second plasma confinement regions at the first axial end portion of the at least one magnetron sputter cathode, and second curved plasma confinement regions (34, 35) connecting the first and second plasma confinement regions at the second axial end portion of the at least one magnetron sputter cathode.

5. The sputter deposition source according to claim 4, wherein the first curved plasma confinement region (33) extends to the front side of the array, and the second curved plasma confinement region (35) extends to the rear side of the array, or vice versa.

6. The first curved plasma confinement region (33) and the second curved plasma confinement region (34) both extend to the front side of the array, or The sputter deposition source according to claim 4, wherein both the first curved plasma confinement region (33) and the second curved plasma confinement region (34) extend to the rear side of the array opposite to the front side.

7. The second magnetron sputter cathode (202) of the array (210), which is positioned adjacent to the at least one magnetron sputter cathode (100), A second rotating target that can rotate around a second axis of rotation (A2), A second magnet assembly (222) is positioned within the second rotating target and configured to provide a closed plasma race track on the surface of the second rotating target, wherein the closed plasma race track extends along the second rotation axis (A2) on the first and second sides of the second magnetron sputter cathode (202) and A sputter deposition source according to any one of claims 1 to 6, comprising:

8. The sputter deposition source according to claim 7, wherein the first side of the at least one magnetron sputter cathode (100) faces the second magnetron sputter cathode (202), and the second side of the second magnetron sputter cathode (202) faces the at least one magnetron sputter cathode (100).

9. The closed plasma race track of the at least one magnetron sputter cathode comprises a first curved plasma confinement region in the upper axial end portion extending to the front of the array, and a second curved plasma confinement region in the lower axial end portion extending to the rear of the array. The closed plasma race track of the second magnetron sputter cathode comprises a first curved plasma confinement region in the upper axial end portion extending to the rear side of the array, and a second curved plasma confinement region in the lower axial end portion extending to the front side of the array. The sputter deposition source according to claim 7, wherein the array optionally comprises, in an alternating arrangement, further magnetron sputter cathodes corresponding to the at least one magnetron sputter cathode and the second magnetron sputter cathode.

10. Designed for inline deposition systems, The first and second sides of the at least one magnetron sputter cathode (100) are oriented in two different directions surrounding a first angle (a1) with respect to the first axis of rotation (A1), The sputter deposition source according to claim 7, wherein the first and second sides of the second magnetron sputter cathode (202) are oriented in two different directions that surround a second angle (a2) smaller than the first angle (a1) with respect to the second axis of rotation (A2).

11. The second magnetron sputter cathode (202) is positioned adjacent to the at least one magnetron sputter cathode (100) in the downstream direction (D) of the inline deposition system, and the array is at least one front sputter cathode (304) positioned downstream (D) from the second magnetron sputter cathode (202), A front sputtering magnet assembly (310) is configured to provide a closed plasma racetrack extending on one side of the front sputtering cathode facing the deposition region (30). The sputter deposition source according to claim 10, further comprising at least one front sputter cathode (304) having the above.

12. The sputter deposition source according to claim 7, further comprising a first shield (21) positioned between the at least one magnetron sputter cathode (100) and the deposition region (30), and a second shield (22) positioned between the second magnetron sputter cathode (202) and the deposition region (30), wherein the deposition window is positioned between the first shield and the second shield.

13. The magnet assemblies of two adjacent magnetron sputter cathodes in the array are arranged asymmetrically with respect to each other. The sputter deposition source according to any one of claims 1 to 6.

14. The array (210) is A first end cathode (203) provided at the first end of the array (210), comprising a third magnet assembly (223) for generating a closed plasma racetrack extending on one side of the first end cathode (203), The array further comprises, and the array can optionally, A second end cathode (204) provided at the second end of the array (210), comprising a fourth magnet assembly (224) for generating a closed plasma racetrack extending on one side of the second end cathode (204). A sputter deposition source according to any one of claims 1 to 6, further comprising:

15. It is a magnetron sputter cathode, A rotating target that can rotate around an axis of rotation, The rotating target comprises a magnet assembly, the magnet assembly is, A first magnet having a first polar magnetic pole oriented radially outward, and A second magnet having a second polar magnetic pole oriented radially outward. Equipped with, The first magnet and the second magnet are magnetron sputter cathodes, each extending adjacent to the other along a closed path for generating a closed plasma racetrack (P) on the surface of the rotating target, with the first plasma confinement region (31) extending parallel to the axis of rotation on the first side of the magnetron sputter cathode and the second plasma confinement region (32) extending parallel to the axis of rotation on the second side of the magnetron sputter cathode opposite the first side.

16. A method for depositing material onto a substrate, Sputtering the material from at least one magnetron sputter cathode having a first magnet assembly positioned within a first rotating target that rotates around a first axis of rotation (A1). Includes, The first magnet assembly provides a closed plasma racetrack (P) on the surface of the first rotating target, with a first plasma confinement region (31) extending parallel to the first rotation axis on a first side of the at least one magnetron sputter cathode, and a second plasma confinement region (32) extending parallel to the first rotation axis on a second side of the at least one magnetron sputter cathode opposite the first side. method.

17. The method according to claim 16, wherein the first side portion faces the first adjacent magnetron sputter cathode, and the second side portion faces the second adjacent magnetron sputter cathode.

18. The method according to claim 16 or 17, wherein the material deposited on the substrate forms a transparent conductive oxide film.

19. The method according to claim 16 or 17, wherein the material deposited on the substrate comprises at least one of IZO, ITO, IGZO, and Ag.

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