WO2017194088A1

WO2017194088A1 - Method and apparatus for vacuum processing

Info

Publication number: WO2017194088A1
Application number: PCT/EP2016/060322
Authority: WO
Inventors: Markus Hanika; Oliver Graw; Thomas Berger
Original assignee: Applied Materials, Inc.
Priority date: 2016-05-09
Filing date: 2016-05-09
Publication date: 2017-11-16
Also published as: KR20190005929A; CN109072400A; CN109072400B

Abstract

A method for vacuum processing of a substrate (10) is provided. The method includes irradiating a substrate surface (11) or a surface of a first material layer on the substrate (10) with ions using an ion etch source (130) provided in a processing region (110) while the substrate (10) is moved through the processing region (110) along a transportation path (20), moving the substrate (10) along the transportation path (20) into a deposition region (120), and depositing at least one second material layer over the substrate surface (11) or over the first material layer while the substrate (10) is stationary.

Description

METHOD AND APPARATUS FOR VACUUM PROCESSING

FIELD

[0001] Embodiments of the present disclosure relate to a method for vacuum processing of a substrate and an apparatus for vacuum processing of a substrate. Embodiments of the present disclosure particularly relate to methods and apparatuses for physical vapor deposition, for example, sputter deposition used in the manufacture of display devices.

BACKGROUND [0002] Techniques for layer deposition on a substrate include, for example, sputter deposition, thermal evaporation, and chemical vapor deposition (CVD). A sputter deposition process can be used to deposit a material layer on the substrate, such as a layer of a conductive material. Substrates provided on substrate carriers can be transported through a processing system. In order to perform multiple processing measures on the substrate, an in- line arrangement of processing modules can be used. An in-line processing system includes a number of subsequent processing modules, wherein processing measures are conducted in one processing module after the other. A plurality of materials such as metals, also including oxides, nitrides or carbides thereof, may be used for deposition on a substrate. Coated materials may be used in several applications and in several technical fields. For instance, substrates for displays are often coated by a physical vapor deposition (PVD) process such as a sputtering process, e.g., to form thin film transistors (TFTs) on the substrate.

[0003] With development of new display technologies and a tendency towards larger display sizes, there is an ongoing demand for layers or layer systems used in displays that provide an improved performance, e.g., with respect to electrical characteristics. As an example, a low contact resistance between conductive layers can be beneficial. Oxidized material at the contact interface between conductive layers can increase the contact resistance, reducing a quality of the manufactured display. [0004] In view of the above, new methods for vacuum processing of a substrate and apparatuses for vacuum processing of a substrate, that overcome at least some of the problems in the art are beneficial. Specifically, methods and apparatuses that allow for a reduced contact resistance between conductive layers are beneficial.

SUMMARY

[0005] In light of the above, a method for vacuum processing of a substrate and an apparatus for vacuum processing of a substrate are provided. Further aspects, benefits, and features of the present disclosure are apparent from the claims, the description, and the accompanying drawings.

[0006] According to an aspect of the present disclosure, a method for vacuum processing of a substrate is provided. The method includes irradiating a substrate surface or a surface of a first material layer on the substrate with ions using an ion etch source provided in a processing region while the substrate is moved through the processing region along a transportation path, moving the substrate along the transportation path into a deposition region, and depositing at least one second material layer over the substrate surface or over the first material layer while the substrate is stationary.

[0007] According to another aspect of the present disclosure, a method for vacuum processing of a substrate is provided. The method includes moving an ion etch source provided in a processing region with respect to a substrate provided on a transportation path, irradiating a substrate surface or a surface of a first material layer on the substrate with ions provided by the ion etch source while the ion etch source is moved, moving the substrate along the transportation path into a deposition region, and depositing at least one second material layer over the substrate surface or over the first material layer. [0008] According to an aspect of the present disclosure, an apparatus for vacuum processing of a substrate is provided. The apparatus includes at least one processing region having at least one ion etch source, at least one deposition region having one or more deposition sources, and a transportation path extending through the at least one processing region and the at least one deposition region. The apparatus is configured to irradiate a substrate surface or a surface of a first material layer on the substrate with ions provided by the at least one ion etch source while the substrate passes the at least one ion etch source. The apparatus is configured to deposit at least one second material layer over the substrate surface or over the first material layer while the substrate is stationary. [0009] According to yet another aspect of the present disclosure, an apparatus for vacuum processing of a substrate is provided. The apparatus includes at least one processing region having at least one ion etch source, at least one deposition region having one or more deposition sources, a transportation path extending through the at least one processing region and the at least one deposition region, and a drive configured to move the at least one ion etch source with respect to the transportation path.

[0010] Embodiments are also directed at apparatuses for carrying out the disclosed methods and include apparatus parts for performing each described method aspect. These method aspects may be performed by way of hardware components, a computer programmed by appropriate software, by any combination of the two or in any other manner. Furthermore, embodiments according to the disclosure are also directed at methods for operating the described apparatus. The methods for operating the described apparatus include method aspects for carrying out every function of the apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS [0011] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments. The accompanying drawings relate to embodiments of the disclosure and are described in the following:

FIG. 1 shows a flowchart of a method for vacuum processing of a substrate according to embodiments described herein;

FIG. 2 shows a schematic view of an apparatus for vacuum processing of a substrate according to embodiments described herein; shows a schematic view of an apparatus for vacuum processing of a substrate according to further embodiments described herein; shows a schematic cross-sectional view of an apparatus for vacuum processing of a substrate according to embodiments described herein; shows a schematic view of an apparatus for vacuum processing of a substrate according to embodiments described herein; shows a schematic view of an apparatus for vacuum processing of a substrate according to further embodiments described herein; and shows a schematic cross-sectional view of a section of a display having a thin film transistor and a pixel electrode according to embodiments described herein.

DETAILED DESCRIPTION OF EMBODIMENTS

[0012] Reference will now be made in detail to the various embodiments of the disclosure, one or more examples of which are illustrated in the figures. Within the following description of the drawings, the same reference numbers refer to same components. Generally, only the differences with respect to individual embodiments are described. Each example is provided by way of explanation of the disclosure and is not meant as a limitation of the disclosure. Further, features illustrated or described as part of one embodiment can be used on or in conjunction with other embodiments to yield yet a further embodiment. It is intended that the description includes such modifications and variations.

[0013] With development of new display technologies and a tendency towards larger display sizes, there is an ongoing demand for layers or layer systems used in displays that provide an improved performance, e.g., with respect to electrical characteristics. As an example, a low contact resistance between layers can be beneficial. Specifically, the occurrence of oxides, such as metal oxides, at a contact interface of layers should be minimized or even avoided in order to provide a low contact resistance between the layers.

[0014] According to the present disclosure, an ion etch source, such as a linear ion etch source, is used to remove oxidized material from a substrate surface or a surface of a first material layer on the substrate. When the oxidized material has been removed, at least one second material layer is deposited on the substrate surface or on the substrate or the first material layer. The first material layer and the at least one second material layer can be conductive layers. As an example, the conductive layers can be selected from metal layers and indium tin oxide (ITO) layers. The etching process using the ion etch source and the deposition of the at least one second material layer can be performed without vacuum breach. A contact resistance between the substrate or the first material layer and the second material layer can be reduced, specifically since a reduced amount of oxidized material or even no oxidized material is present at the contact interface between the substrate or the first material layer and the second material layer. It is to be understood that the present disclosure is not limited to the removal of oxidized material from a substrate surface or a surface of a first material layer on the substrate. The embodiments described herein, and particularly the ion etch source, can be used for other surface treatment processes, e.g., a removal of other materials or material layers from a substrate or a material layer on the substrate. [0015] FIG. 1 shows a flowchart of a method for vacuum processing of a substrate according to embodiments described herein.

[0016] According to an aspect of the present disclosure the method includes, in block 1100, irradiating a substrate surface or a surface of a first material layer on the substrate with ions using an ion etch source provided in a processing region while the substrate is moved through the processing region along a transportation path. The method includes in block 1200 a moving of the substrate along the transportation path into a deposition region, and, in block 1300, depositing at least one second material layer over the substrate surface or over the first material layer while the substrate is stationary. According to some embodiments, which can be combined with other embodiments described herein, the ion etch source is a linear ion etch source. [0017] In some implementations, the method further includes depositing the first material layer over the substrate surface. Specifically, the first material layer can be deposited before the etching process using the ion etch source is conducted. Oxidized material can be removed from the substrate surface or the surface of the first material layer before the at least one second material layer is deposited, and a contact resistance at the contact interface between the at least one second material layer and the substrate or the first material layer can be improved.

[0018] According to some embodiments, which can be combined with other embodiments described herein, the method can further include irradiating a surface of the at least one second material layer with ions using the ion etch source used in the irradiation of the substrate surface or the surface of the first material layer or with another ion etch source configured similarly or identically to the ion etch source used in the irradiation of the substrate surface or the surface of the first material layer.

[0019] As an example, the method of the present disclosure can include process sequences like (i) deposition of the first material layer, irradiating (etching) a surface of the first material layer, and deposition of the at least one second material layer; (ii) irradiating (etching) of the substrate surface and deposition of the at least one (second) material layer on the substrate surface; (iii) irradiating (etching) the substrate surface and deposition of two or more (second) material layers (i.e., the at least one second material layer can include two or more second material layers); (iv) deposition of the first material layer, irradiating (etching) the first material layer, deposition of the at least one second material layer, and irradiating (etching) the second material layer.

[0020] In some implementations, the at least one second material layer includes two or more second material layers. The two or more second material layers can be made of the same or of different materials. As an example, one second material layer of the two or more second material layers can be irradiated with ions using the ion etch source before another second material layer of the two or more second material layers is deposited thereon.

[0021] The processing region and the deposition region can be regions within a vacuum chamber of a vacuum processing system. In other implementations, the processing region and the deposition region can be provided by different vacuum chambers connected to each other. The processing region and the deposition region can be separated from each other, for example, using at least one of locks, valves and separation devices, such as a gas separation shielding. The processing region and the deposition region will be further explained with reference to FIGs. 2 to 6. [0022] According to some embodiments, the method provides a combination of a dynamic etching process and a stationary or static deposition process. The terms "stationary" and "static" as used throughout the present disclosure can be understood in the sense that the substrate is substantially not moving with respect to the vacuum chamber and/or the deposition sources provided in the deposition region. [0023] Specifically, the deposition process can be a static deposition process, e.g., for display processing. It should be noted that "static deposition processes", which differ from dynamic deposition processes do not exclude any movement of the substrate as would be appreciated by a skilled person. A static deposition process can include, for example, at least one of the following: a static substrate position during deposition; an oscillating substrate position during deposition; an average substrate position that is essentially constant during deposition; a dithering substrate position during deposition; a wobbling substrate position during deposition; a deposition process for which the cathodes are provided in one vacuum chamber, i.e. a predetermined set of cathodes are provided in the vacuum chamber; a substrate position wherein the vacuum chamber has a sealed atmosphere with respect to neighboring chambers, e.g. by closing valve units separating the vacuum chamber from an adjacent chamber during deposition of the layer; or a combination thereof. A static deposition process can be understood as a deposition process with a static position, a deposition process with an essentially static position, or a deposition process with a partially static position of the substrate. In view of this, a static deposition process, in which the substrate position can in some cases be not fully without any movement during deposition, can still be distinguished from a dynamic deposition process.

[0024] According to some embodiments, which can be combined with other embodiments described herein, the ion etch source can be moving or stationary, for example, while the substrate surface and/or the surface of the first material layer is irradiated with the ions. [0025] In some implementations, the ion etch source can be moving with respect to the transportation path while the substrate is transported along the transportation path. As an example, the method can further include an irradiating of the substrate surface or the surface of the first material layer with ions while the ion etch source is moved. Specifically, both the substrate and the ion etch source can be moving while the substrate surface or the surface of the first material layer is irradiated with the ions provided by the ion etch source. Moving both the substrate and the ion etch source allows for a fast etching process.

[0026] In other implementations, the ion etch source can be stationary while the substrate passes the ion etch source. As an example, the ion etch source can be stationary while the substrate surface or the surface of the first material layer is irradiated with the ions from the ion etch source. The stationary ion etch source allows for a simple configuration of the apparatus.

[0027] According to a further aspect of the present disclosure a method for vacuum processing of a substrate includes moving an ion etch source provided in a processing region with respect to a substrate provided on a transportation path, irradiating a substrate surface or a surface of a first material layer on the substrate with ions provided by the ion etch source while the ion etch source is moved, moving the substrate along the transportation path into a deposition region, and depositing at least one second material layer over the substrate surface or over the first material layer. [0028] In some implementations, the method further includes depositing the first material layer over the substrate surface. Specifically, the first material layer can be deposited before the etching process using the ion etch source is conducted. Oxidised material can be removed from the substrate surface or the surface of the first material layer before the at least one second material layer is deposited, and a contact resistance at the interface between the at least one second material layer and the substrate or the first material layer can be improved.

[0029] According to some embodiments, which can be combined with other embodiments described herein, moving the ion etch source includes a moving in at least one of a first direction parallel to the transportation path and a second direction perpendicular to the transportation path. As an example, the first direction can be a horizontal direction and/or the second direction can be a vertical direction. The ion etch source, such as the linear ion etch source, can be vertically and/or horizontally scanned over the substrate surface, for example, to remove oxidised material from the substrate surface or the surface of the first material layer. The moving of the ion etch source and the first direction and the second direction can improve an efficiency of the etching process. [0030] The term "vertical direction" is understood to distinguish over "horizontal direction". That is, the "vertical direction" relates to a substantially vertical movement of the ion etch source, wherein a deviation of a few degrees, e.g. up to 10° or even up to 30°, from an exact vertical direction or vertical movement is still considered as a "substantially vertical direction" or a "substantially vertical movement". The vertical direction can be substantially parallel to the force of gravity. Likewise, the "horizontal direction" relates to a substantially horizontal movement of the ion etch source, wherein a deviation of a few degrees, e.g. up to 10° or even up to 30°, from an exact horizontal direction or horizontal movement is still considered as a "substantially horizontal direction" or a "substantially horizontal movement". [0031 ] In some embodiments, the ion etch source is moved sequentially or simultaneously in the first direction and the second direction. The ion etch source can move along a continuous or discontinuous movement path in a plane spanned by the first direction and the second direction. As an example, the ion etch source can move along a continuous movement path, when the ion etch source is moved simultaneously in the first direction and the second direction. The ion etch source can move along a discontinuous movement path, when the ion etch source is moved sequentially in the first direction and the second direction.

[0032] According to some embodiments, which can be combined with other embodiments described herein, an operation of the ion etch source is based on a position of the substrate on the transportation path. Specifically, an on/off-mode of the ion etch source can be triggered by a movement and/or position of the substrate. As an example, the ion etch source can be switched on when the substrate enters the processing region. The ion etch source can be switched off when the substrate leaves the processing region and, for example, enters the deposition region. In some implementations, the ion etch source can be repeatedly switched on and off while the substrate moves through the processing region. [0033] In some implementations, the substrate is moving or stationary while the substrate surface or the surface of the first material layer is irradiated with the ions. As an example, the method further includes moving the substrate along the transportation path while the substrate surface or the surface of the first material layer is irradiated with the ions. Specifically, both the ion etch source and the substrate can be moving during the etching process. Moving both the ion etch source and the substrate can shorten a process time of the etching process. A throughput of the apparatus can be improved.

[0034] In other examples, the substrate is stationary positioned on the transportation path while the ion etch source moves with respect to the transportation path to irradiate the substrate surface for the surface of the first material layer with the ions. Keeping the substrate stationary allows for a flexible selection of the process time of the etching process. Specifically, the process time can be selected such that substantially the whole oxidised material is removed from the substrate surface or the surface of the first material layer.

[0035] According to some embodiments, which can be combined with other embodiments described herein, a moving speed of the substrate along the transportation path and/or a moving speed of the ion etch source is substantially constant during at least one of the irradiation with ions and the deposition of the first material layer and/or the at least one second material layer. According to further embodiments, which can be combined with other embodiments described herein, a moving speed of the substrate along the transportation path and/or a moving speed of the ion etch source can be varied or changed (i.e., a non-uniform moving speed can be provided) during at least one of the irradiation with ions and the deposition of the first material layer and/or the at least one second material layer. As an example, the moving speed of the substrate along the transportation path and/or the moving speed of the ion etch source can be varied or changed during the irradiation with ions for providing local etch rate changes at the substrate.

[0036] In some embodiments, the second material layer is deposited over the substrate surface or over the surface of the first material layer while the substrate is stationary. Specifically, the deposition process can be a stationary or static deposition process. In further embodiments, the second material layer is deposited over the substrate surface or over the first material layer while the substrate is moved through the deposition region along the transportation path. Specifically, the deposition process can be a dynamic deposition process.

[0037] When reference is made to the term "over", i.e. one layer being over the other, it is understood that, starting from the substrate, a first material layer is deposited over the substrate, and the second material layer, deposited after the first material layer, is thus over the first layer and over the substrate. In other words, the term "over" is used to define an order of layers, layer stacks, and/or films wherein the starting point is the substrate. This is irrespective of whether the layer stack is considered upside down or not.

[0038] The term "over" shall embrace embodiments where one or more further material layers are provided between the substrate and the first material layer and/or the first material layer and the second material layer. In other words, the first material layer is not directly disposed on the substrate and/or the second material layer is not directly disposed on the first material layer. However, the present disclosure is not limited thereto and the term "over" shall embrace embodiments where no further layers are provided between the substrate and the first material layer and/or the first material layer and the second material layer. In other words, the first material layer can be disposed directly on the substrate and can be in direct contact with the substrate. The second material layer can be disposed directly on the first material layer and can be in direct contact with the first material layer.

[0039] According to some embodiments, which can be combined with other embodiments described herein, at least one of the first material layer and the second material layer can be a conductive layer. As an example, the first material layer can be the first conductive layer and the second material layer can be a second conductive layer. As an example, the material of the first material layer and/or the second material layer is selected from the group consisting of a metal, a metal alloy, titanium, aluminum, indium tin oxide (ITO), and any combination thereof.

[0040] In some embodiments, the first material layer can provide a source of a display TFT and/or the second material layer can provide a pixel electrode of a display. As an example, the first material layer can be made of a metal or metal alloy, including titanium, aluminum, and any combination thereof. The second material layer can be made of indium tin oxide (ITO). The TFT will be explained in greater detail with reference to FIG. 7. [0041 ] According to some embodiments, which can be combined with other embodiments described therein, the substrate is transported along the transportation path in a substantially vertical orientation. As an example, the substrate surface or the surface of the first material layer is irradiated with the ions while the substrate is in a substantially vertical orientation. As used throughout the present disclosure "substantially vertical" is understood particularly when referring to the substrate orientation, to allow for a deviation from the vertical direction or orientation of ±20° or below, e.g. of ±10° or below. This deviation can be provided for example because a substrate support with some deviation from the vertical orientation might result in a more stable substrate position. Yet, the substrate orientation, e.g., during the etching process and/or the deposition process is considered substantially vertical, which is considered different from the horizontal substrate orientation.

[0042] The term "substrate" as used herein shall embrace substrates which are typically used for display manufacturing. The substrates can be large area substrates. For example, substrates as described herein shall embrace substrates which are typically used for an LCD (Liquid Crystal Display), a PDP (Plasma Display Panel), and the like. For instance, a large area substrate can be GEN 4.5, which corresponds to about 0.67 m² substrates (0.73x0.92m), GEN 5, which corresponds to about 1.4 m² substrates (1.1 m x 1.3 m), GEN 6, which corresponds to about 2.8 m² substrates (1.85 m x 1.5 m), GEN 7.5, which corresponds to about 4.29 m² substrates (1.95 m x 2.2 m), GEN 8.5, which corresponds to about 5.7m² substrates (2.2 m x 2.5 m), or even GEN 10, which corresponds to about 8.7 m² substrates (2.85 m x 3.05 m). Even larger generations such as GEN 11 and GEN 12 and corresponding substrate areas can similarly be implemented.

[0043] The term "substrate" as used herein shall particularly embrace substantially inflexible substrates, e.g., a wafer, slices of transparent crystal such as sapphire or the like, or a glass plate. In particular, the substrates can be glass substrates and/or transparent substrates. However, the present disclosure is not limited thereto and the term "substrate" may also embrace flexible substrates such as a web or a foil. The term "substantially inflexible" is understood to distinguish over "flexible". Specifically, a substantially inflexible substrate can have a certain degree of flexibility, e.g. a glass plate having a thickness of 0.5 mm or below, wherein the flexibility of the substantially inflexible substrate is small in comparison to the flexible substrates. [0044] According to embodiments described herein, the method for vacuum processing of a substrate can be conducted using computer programs, software, computer software products and the interrelated controllers, which can have a CPU, a memory, a user interface, and input and output devices being in communication with the corresponding components of the apparatus.

[0045] FIG. 2 shows a schematic view of an apparatus 100 for vacuum processing of a substrate 10 according to embodiments described herein.

[0046] According to an aspect of the present disclosure, the apparatus 100 includes at least one processing region 110 having at least one ion etch source, such as at least one linear ion etch source 130, at least one deposition region 120 having one or more deposition sources 140, and a transportation path 20 extending through the at least one processing region 110 and the at least one deposition region 120. The apparatus 100 can be configured to perform the method for vacuum processing of a substrate according to the embodiments described herein. In the following, the at least one linear ion etch source 130 is exemplarily described. However, it is to be understood that the present disclosure is not limited thereto and that other geometries or types of ion etch sources can be used.

[0047] The apparatus 100 can include a substrate carrier 30 configured to support the substrate 10. The substrate carrier 30 having the substrate 10 positioned thereon can be transported along the transportation path 20. The substrate carrier 30 can include a plate or a frame configured for supporting the substrate 10, for example, using a support surface provided by the plate or frame. Optionally, the substrate carrier 30 can include one or more holding devices (not shown) configured for holding the substrate 10 at the plate or frame. The one or more holding devices can include at least one of mechanical and/or magnetic clamps. [0048] In some implementations, the substrate carrier 30 includes, or is, an electrostatic chuck (E-chuck). The E-chuck can have a supporting surface for supporting the substrate thereon. In one embodiment, the E-chuck includes a dielectric body having electrodes embedded therein. The dielectric body can be fabricated from a dielectric material, preferably a high thermal conductivity dielectric material such as pyrolytic boron nitride, aluminum nitride, silicon nitride, alumina or an equivalent material; or the dielectric body may be fabricated from a very thin but less thermally-conductive material such as polyimide. The electrodes may be coupled to a power source which provides power to the electrodes to control a chucking force. The chucking force is an electrostatic force acting on the substrate to fix the substrate on the supporting surface. [0049] The at least one linear ion etch source 130 can be an argon ion source configured to emit a beam of energetic particles (ions) as indicated with reference numeral 134. In some implementations, the at least one linear ion etch source 130 is a vertical linear ion etch source. The at least one linear ion etch source 130 can be configured to provide an inductively coupled plasma (ICP). As an example, the at least one linear ion etch source 130 can include a coil electrically connected to a power supply, such as a radio frequency (RF) power supply. A current can be applied to the coil and a plasma can be generated by excitation of a process gas, for example argon, inside the at least one linear ion etch source. In further implementations, the at least one linear ion etch source 130 can be configured to provide a charged coupled plasma (CCP) using a plate. [0050] The term "linear" can be understood in the sense that the linear ion etch source 130 has a major dimension and a minor dimension defining an emission area of the ions (e.g., a substantially rectangular area), wherein the minor dimension is less than the major dimension. For example, the minor dimension can be less than 10%, specifically less than 5% and more specifically less than 1% of the major dimension. The major dimension can extend substantially vertically. In other words, the at least one linear ion etch source 130 can be a vertical linear ion etch source. According to some embodiments, a beam width of the ions provided by the at least one linear ion etch source 130, e.g., the emission area, can be in a range of between 1mm to 3000mm, specifically in a range of between 30mm to 2100mm, and can more specifically less than 50mm. The beam width can be defined perpendicular to the linear extension of the at least one linear ion etch source 130.

[0051] In some implementations, the at least one linear ion etch source 130 can have one or more outlets or ion sources arranged along a vertical line, e.g., in the major dimension, configured to provide the ions and/or the emission area. As an example, one continuous outlet or ion source can be provided. In other examples, a plurality of outlets or ion sources can be arranged along a line. For instance, the linear ion etch source can consist of multiple point sources closely aligned next to each other along the line. [0052] The ions are used to treat the substrate surface 11 and/or the surface of the at least one first material layer on the substrate 10, for example, to provide etching, cleaning, densification, and/or surface smoothing. Specifically, the ions can be used to remove oxidized material from the substrate surface 11 and/or the surface of the first material layer in order to provide improved electrical contact with a subsequently deposited material layer, such as the second material layer. The first material layer can be the very first material layer on the substrate surface (i.e., in direct contact with the substrate surface) or can be the uppermost layer of a plurality of first material layers on the substrate surface (i.e., not in direct contact with the substrate surface). In some implementations, the etching of the first material layer is performed if the first material layer is the very first material layer on the substrate surface, but is not performed if the first material layer is the uppermost layer of a plurality of first material layers on the substrate surface.

[0053] In some implementations, the apparatus 100 is configured to provide a combination of a dynamic etching process and a static deposition process. The apparatus 100 can be configured to irradiate the substrate surface 11 or the surface of the first material layer on the substrate 10 with ions (indicated with reference numeral 134) provided by the at least one linear ion etch source 130 while the substrate 10 passes the at least one linear ion etch source 130. As an example, the substrate surface 11 and/or the surface of the first material layer is irradiated during the transportation of the substrate 10 or substrate carrier 30 along the transportation path 20, for example, in a direction towards the at least one deposition region 120 (the transport direction 1). According to some embodiments, the apparatus 100 is configured to deposit at least one second material layer over the substrate surface 11 or over the first material layer while the substrate 10 is stationary.

[0054] The term "processing region" can be understood as a space or area where the substrate 10 can be provided or positioned so that the substrate 10 can be irradiated with the ions provided by the at least one linear ion etch source 130. The term "deposition region" can be understood as a space or area where the substrate 10 can be provided or positioned so that the substrate 10 can be coated with a material provided by the one or more deposition sources 140. [0055] According to some embodiments, which can be combined with other embodiments described herein, the apparatus 100 can include one or more vacuum chambers. The at least one processing region 110 and the at least one deposition region 120 can be provided by the same (one single) vacuum chamber. The vacuum chamber can be divided in two or more portions or areas providing the at least one processing region 110 and the at least one deposition region 120. The vacuum chamber can be divided using one or more separation devices 115, for example, a gas separation shielding. In other implementations, no separating device is provided between the at least one processing region 110 and the at least one deposition region 120. The at least one processing region 110 and the at least one deposition region 120 can be provided in the vacuum chamber without any separation there between. In yet further implementations, the at least one process region 110 and the at least one deposition region 120 can be provided by different vacuum chambers connected to each other, for example, using a gate and/or a valve. According to the embodiments described therein, the at least one processing region 110 and the at least one deposition region 120 are connected to each other vacuum- wise, so that the substrate 10 stays within the vacuum environment during the transfer from the at least one processing region 110 to the at least one deposition region 120, or vice versa.

[0056] According to some embodiments, which can be combined with other embodiments described herein, the at least one processing region 110 includes two or more processing regions each having one or more linear ion etch sources. Alternatively or additionally, the at least one deposition region 120 includes two or more deposition regions each having one or more deposition sources. Specifically, the apparatus can have multiple processing regions and/or multiple deposition regions for conducting multiple irradiation processes and multiple deposition processes, respectively.

[0057] The term "vacuum" as used throughout the present disclosure can be understood as a space that is substantially devoid of matter, e.g., a space from which all or most of the air or gas has been removed, except for process gases that are used in a deposition process, such as a sputter deposition process. As an example, the term "vacuum" can be understood in the sense of a technical vacuum having a vacuum pressure of less than, for example, 10 mbar. One or more vacuum pumps, such as turbo pumps and/or cryo-pumps, can be connected to the one or more vacuum chambers providing the at least one processing region 110 and the at least one deposition region 120 for generation of the vacuum. [0058] The term "transportation path" as used throughout the present disclosure can be understood as a way along which the substrate 10 or the substrate carrier 30 having the substrate 10 positioned thereon can be moved or conveyed, for example, through the at least one processing region 110 and the at least one deposition region 120. As an example, the transportation path can be a linear transportation path. The transportation path 20 can define a transport direction 1 for the substrate 10 or the substrate carrier 30 through the at least one processing region 110 and the at least one deposition region 120. The transportation path 20 can be a unidirectional transportation path or can be a bidirectional transportation path.

[0059] The apparatus 100 can have at least two transportation paths, such as the transportation path 20 and another transportation path (not shown). The at least two transportation paths can be provided so that a first substrate carrier having a first substrate positioned thereon may overtake a second substrate on a second substrate carrier, for example, when the second substrate is being coated. The at least two transportation paths can extend substantially parallel to each other, for example, in the transport direction 1 of the substrate 10 or substrate carrier 30. In some implementations, the at least two transportation paths can be displaced with respect to each other in the direction perpendicular to the transport direction 1 of the substrate carrier 30. The term "substantially parallel" relates to a substantially parallel orientation e.g. of direction(s) and/or path(s), wherein a deviation of a few degrees, e.g. up to 10° or even up to 15°, from an exact parallel orientation is still considered as "substantially parallel".

[0060] The transportation path(s) can be provided by respective tracks. As an example, the transportation path 20 can be provided by a track and the other transportation path can be provided by another track. As used throughout the present disclosure, the term "track" can be defined as a space or device that accommodates or supports the substrate carrier 30, which can be an E-chuck. As an example, the track can accommodate or support the substrate carrier 30 mechanically (using, for example, rollers), contactlessly (using, for example, magnetic fields and respective magnetic forces), or using a combination thereof.

[0061] FIG. 3 shows a schematic view of an apparatus 200 for vacuum processing of a substrate 10 according to further embodiments described herein. The apparatus 100 can be configured to perform the method for vacuum processing of a substrate according to some embodiments described herein. [0062] According to some embodiments, which can be combined with other embodiments described herein, the apparatus 200 includes a drive configured to move the at least one linear ion etch source 130 with respect to the transportation path 20. In some implementations, the drive can be configured to move the at least one ion etch source, such as the at least one linear ion etch source 130, substantially parallel and/or substantially perpendicular to the transportation path 20. As an example, the drive can be configured to move the at least one linear ion etch source 130 in at least one of a first direction (indicated with reference numeral 2) parallel to the transportation path 20 and a second direction perpendicular to the transportation path. As an example, the first direction can be a horizontal direction and/or the second direction can be a vertical direction. The term "vertical direction" is understood to distinguish over "horizontal direction". That is, the "vertical direction" relates to a substantially vertical movement of the linear ion etch source, wherein a deviation of a few degrees, e.g. up to 10° or even up to 30°, from an exact vertical direction or vertical movement is still considered as a "substantially vertical direction" or a "substantially vertical movement". The vertical direction can be substantially parallel to the force of gravity.

[0063] The apparatus 200 can include a track 132 in the at least one processing region 110. The track 132 can be configured to movably support the at least one linear ion etch source 130. The track 132 can be substantially parallel to the transportation path 20. The drive can be configured to move the at least one linear ion etch source 130 along the track 132 in the first direction. As an example, the drive can be configured to move the at least one linear ion etch source 130 back and forth along the track 132. In some embodiments, the drive is configured to move the at least one linear ion etch source 130 substantially perpendicular to the track 132, for example, in the second direction which can be the vertical direction. The movements in the first direction and the second direction can include bidirectional movements in the first direction and the second direction. As an example, the movement of the linear ion etch source can include back and forth movements in the first direction (as indicated with the double-ended arrow in FIG. 3) and/or back and forth movements in the second direction.

[0064] In some embodiments, the drive is configured to move the at least one linear ion etch source 130 sequentially or simultaneously in the first direction and the second direction. The at least one linear ion etch source 130 can move along a continuous or discontinuous movement path in a plane spanned by the first direction and the second direction. The plane can be a substantially vertically oriented plane. As an example, the at least one linear ion etch source 130 can move along a continuous movement path, when the at least one linear ion etch source 130 is moved simultaneously in the first direction and the second direction. The at least one linear ion etch source 130 can move along a discontinuous movement path, when the at least one linear ion etch source 130 is moved sequentially in the first direction and the second direction.

[0065] According to some embodiments, which can be combined with other embodiments described herein, the apparatus 200 can be configured to conduct the etching process with the substrate 10 being stationary or moving. As an example, the apparatus 200 can be configured to irradiate the substrate surface 11 or a surface of a first material layer on the substrate 10 with ions provided by the at least one linear ion etch source 130 while the substrate 10 passes the at least one linear ion etch source 130 or while the substrate 10 is stationary on the transportation path 20. Specifically, both the at least one linear ion etch source 130 and the substrate 10 can be moving during the etching process. In other examples, the substrate is stationary positioned on the transportation path 20 while the at least one linear ion etch source 130 moves with respect to the transportation path 20 to irradiate the substrate surface 11 or the surface of the first material layer with the ions.

[0066] FIG. 4 shows a schematic cross-sectional view of an apparatus for vacuum processing of a substrate 10 according to embodiments described herein. The at least one ion etch source, such as the at least one linear ion etch source 130, is provided on the track 132.

The at least one linear ion etch source 130 provides ions (indicated with reference numeral

134) for irradiation of the substrate 10 that is supported on the substrate carrier 30. The apparatus can include the drive configured to move the at least one linear ion etch source 130 along the track 132 in the first direction. Additionally or alternatively, the drive is configured to move the at least one linear ion etch source 130 in the second direction, wherein the second direction can be the vertical direction 3.

[0067] According to some embodiments, which can be combined with other embodiments described therein, the apparatus for vacuum processing can include a magnetic levitation system (not shown) configured for a contactless levitation of the substrate carrier 30 in, for example, the vertical orientation. The substrate carrier 30 can be an E-chuck. The term "contactless levitation" or as used throughout the present disclosure can be understood in the sense that a weight of the substrate carrier 30 is not carried or held by a mechanical contact or mechanical forces, but is carried or held by a magnetic force. Specifically, the substrate carrier 30 is held in a levitating or floating state using magnetic forces instead of mechanical 5 forces. As an example, the magnetic levitation system has no mechanical devices, such as rollers, that support the weight of the substrate carrier 30. In some implementations, there can be no mechanical contact between the substrate carrier 30 and the apparatus for vacuum processing at all. The contactless levitation is beneficial in that no particles are generated due to a mechanical contact between the substrate carrier 30 and sections of the apparatus 10 for vacuum processing, such as rollers. Accordingly, a purity of the layers deposited on the substrate 10 can be improved, in particular since a particle generation is minimized or even avoided.

[0068] The magnetic force provided by the magnetic levitation system is sufficient to hold the substrate carrier 30 having the substrate 10 positioned thereon in the floating state.

15 Specifically, the magnetic force can be equal to a total weight of the substrate carrier 30. The total weight of the substrate carrier 30 can include at least a weight of the (empty) substrate carrier and a weight of the substrate 10. As an example, a magnetic field generated by the magnetic levitation system is selected such that the magnetic force is equal to the total weight of the substrate carrier 30 in order to keep the substrate carrier 30 in the suspended or

20 levitating state.

[0069] FIG. 5 shows a schematic view of an apparatus 500 for vacuum processing of a substrate 10 according to embodiments described herein.

[0070] The apparatus 500 includes a plurality of regions, such as a first deposition region 508, the at least one processing region 510, and a second deposition region 520. The plurality

25 of regions can be provided in one vacuum chamber. Alternatively, the plurality of regions can be provided in different vacuum chambers connected to each other. As an example, each vacuum chamber can provide one region. Specifically, a first vacuum chamber can provide the first deposition region 508, a second vacuum chamber can provide the at least one processing region 510, and a third vacuum chamber can provide the second deposition region

30 520. In some implementations, the first vacuum chamber and the third vacuum chamber can be referred to as "deposition chambers". The second vacuum chamber can be referred to as "processing chamber" or "etching chamber". Further vacuum chambers or regions can be provided adjacent to the regions shown in the example of FIG. 5.

[0071 ] The vacuum chambers or regions can be separated from adjacent regions by a valve having a valve housing 504 and a valve unit 505. After a substrate carrier 30 with the substrate 10 thereon is, as indicated by arrow "1", inserted in a region, such as the at least one processing region 510, the valve unit(s) can be closed. The atmosphere in the regions can be individually controlled by generating a technical vacuum, for example, with vacuum pumps connected to the regions and/or by inserting one or more process gases, for example, in the first deposition region 508 and/or the second deposition region 520. A transportation path 20, such as a linear transportation path, can be provided in order to transport the substrate carrier 30, having the substrate 10 thereon, into, through and out of the regions. The transportation path 20 can extend at least in part through the first deposition region 508, the at least one processing region 510, and the second deposition region 520.

[0072] The apparatus 500 includes the at least one linear ion etch source 130 in the at least one processing region 510. The at least one linear ion etch source 130 can be configured according to the embodiments described herein. Within the deposition regions, such as the first deposition region 508 and the second deposition region 520, one or more deposition sources are provided. As an example, a first deposition sources 540 can be provided in the first deposition region 508. A second deposition source 550 can be provided in the second deposition region 520. A deposition source of the one or more deposition sources can include one or more cathodes and one or more anodes. As an example, the first deposition source 540 can include a first cathode 542 and a first anode 544. The second deposition source 550 can include a second cathode 552 and a second anode 554. For example, the one or more cathodes can be rotatable cathodes having the sputter targets of the material to be deposited on the substrate 10. The one or more cathodes can have a magnet assembly therein, and magnetron sputtering can be conducted for depositing of the layers.

[0073] The one or more cathodes and the one or more anodes can be electrically connected to a DC power supply. The one or more cathodes are connected to the DC power supply together with the one or more anodes for collecting electrons during sputtering. According to yet further embodiments, which can be combined with other embodiments described herein, at least one of the one or more cathodes can have a corresponding, individual DC power supply. Specifically, the first deposition source 540 can have a first DC power supply 546 and the second deposition source 550 can have a second DC power supply 556.

[0074] As used herein, "magnetron sputtering" refers to sputtering performed using a magnetron or magnet assembly, i.e., a unit capable of generating a magnetic field. Such a magnet assembly consists of one or more permanent magnets. These permanent magnets can be arranged within a rotatable sputter target or coupled to a planar sputter target in a manner such that the free electrons are trapped within the generated magnetic field generated below the rotatable target surface. Such a magnet assembly may also be arranged coupled to a planar cathode. According to some embodiments described herein, sputtering can be conducted as DC (direct current) sputtering. However, other sputtering methods such as MF (middle frequency) sputtering, RF (radio frequency) sputtering, or pulse sputtering can also be applied.

[0075] FIG. 5 shows the deposition regions having one deposition source including one cathode and one anode. Particularly for applications for large area deposition, an array of deposition sources can be provided within at least one of the regions, such as the first deposition region 508 and the second deposition region 520.

[0076] In some implementations, the first material layer is deposited on the substrate 10 in the first deposition region 508 using the first deposition source 540. As an example, the first material layer can be a metal layer of a TFT used in the display. Specifically, the first material layer can provide a drain electrode of a TFT. The substrate 10 having the first material layer is deposited thereon is transported from the first deposition region 508 into the at least one prossessing region 510 having the at least one linear ion etch source 130. The at least one linear ion etch source 130 can be stationary. Specifically, the at least one linear ion etch source 130 can provide the ions while the substrate 10 on the substrate carrier 30 passes the at least one linear ion etch source 130. As an example, the substrate surface or the first material layer on the substrate 10 can be irradiated with the ions from the at least one linear ion etch source 130 while the substrate carrier 30 is transported along the transportation path 20 through the at least one processing region 510. The etching process removes oxidized material from the substrate surface and/or the surface of the first material layer. [0077] Having completed the etching process, the substrate 10 can be transferred into the second deposition region 520 for deposition of a second material layer, for example, an indium tin oxide (ITO) layer, over the substrate 10. As an example, the second material layer provide a pixel electrode of the display, such as an electrode of a static pixel. A contact resistance between the first material layer and the second material layer can improved, since oxidized material has been removed from the first material layer during the etching process.

[0078] FIG. 6 shows a schematic view of an apparatus 600 for vacuum processing of a substrate according to embodiments described herein. The apparatus 600 is similar to the apparatus 500 described above with reference to FIG. 5, the difference being that the at least one linear ion etch source 130 is movable with respect to the transportation path 20. The movable linear ion etch source can be configured as described with reference to, for example, FIGs. 1, 3 and 4.

[0079] FIG. 7 shows a schematic cross-sectional view of a section of a display 400 having a thin film transistor and a pixel electrode according to embodiments described herein. The TFT according to the embodiments described herein can, for example, be used in display devices, such as liquid crystal displays (LCDs) and/or organic light emitting diode (OLED) displays.

[0080] The display includes a substrate 410, for example, a glass substrate. A gate electrode 420 is formed on or over the substrate 410. The gate electrode 420 can be deposited using a PVD process. As an example, the gate electrode 420 can include a metal. The metal can be selected from the group including Cr, Cu, Mo, Ti, and any combination thereof. The metal can also be a metal stack including two or more of the metals selected from the group including Cr, Cu, Mo, Ti, and any combination thereof. [0081] A gate insulator 430 is formed at least over the gate electrode 420, e.g., by a PECVD process. As an example, the gate insulator 430 can include at least one of SiN_x and SiO_y. The gate insulator can have at least two sub-layers, e.g., at least one SiN_x layer and at least one SiO_y layer. A channel layer 440 is formed on or over the gate insulator 430. The channel layer is the active (semiconducting) layer. The material of the channel layer 440 can be selected from the group consisting of ZnON, LTPS (p-Si), IGZO, and a-Si. An etch stopper 470, e.g., of SiO_x, is formed on the channel layer 440, e.g., by a PECVD process.

[0082] A source electrode 450 and a drain electrode 460 are formed on the channel layer 440, e.g., by a PVD process. The source electrode 450 and the drain electrode 460 (for example, the first material layer according to the embodiments described therein) can be made of a metal. The metal can be selected from the group including Cr, Cu, Mo, Ti, and any combination thereof. The metal can also be a metal stack including two or more of the metals selected from the group including Al, Ti, Cr, Cu, Mo, and any combination thereof. A passivation layer 480 is formed at least over the source electrode 450 and the drain electrode 460. The passivation layer 480 can, for example, be formed by a PECVD process.

[0083] A second material layer 490 can be provided in contact with the first material layer, for example, the drain electrode 460. In some implementations, the second material layer 490 provides a pixel electrode of the display, for example, a static pixel. The second material layer 490, specifically the pixel electrode, can be made of indium tin oxide (ITO).

[0084] The method and the apparatuses according to the embodiments described herein can be utilized at least in the manufacture of the first material layer, for example, the drain electrode 460, and the second material layer 490, for example, the pixel electrode. Specifically, the first material layer can be deposited and the etching process using the linear ion etch source can be conducted to remove oxidized material from a surface of the first material layer. A section of the second material layer 490 can then be deposited directly on the first material layer. Contact characteristics between the first material layer and the second material layer 490 can be improved, specifically since a reduced amount of oxidized material or even no oxidized material is present at the contact interface between the first material layer and the second material layer 490. A contact resistance between the first material layer and the second material layer 490 can be reduced and a performance of the display can be improved.

[0085] In some implementations, a contact resistance of source/drain metal layer stacks can be improved by etch removal of an oxidized metal layer of the source/drain metal layer stack. As an example, the stack can be a Ti/Al/Ti layer stack, which is at least partially oxidized during a TFT fabrication flow. The present disclosure provides an etching process, such as a dynamic etching process, before the static pixel ITO deposition. The whole process flow is under vacuum, and the Ti does not oxidize again before the ITO deposition.

[0086] According to some embodiments, the apparatus includes a long high vacuum module having a static linear vertical ion source for etching which is turned on/off triggered, for example, by the moving-by substrate to remove the oxide. In further embodiments, the apparatus includes a high vacuum module having a moving linear ion source ("hybrid process") for etching which is scanned along the substrate (horizontally and/or vertically). The on/off of the ion etch source can be triggered depending on a substrate-etch source position. There is no vacuum break between the etching and the deposition. After the etching the next layer, for example, pixel ITO can be deposited with a low contact resistance.

[0087] According to the present disclosure, an ion etch source, such as a linear ion etch source, is used to remove oxidized material from a substrate surface or a surface of a first material layer on the substrate. When the oxidized material has been removed, a second material layer is deposited on the substrate surface or on the substrate or the first material layer. The first material layer and the second material layer can be conductive layers. As an example, the conductive layers can be selected from metal layers and indium tin oxide (ITO) layers. The etching process using the ion etch source and the deposition of the second material layer can be performed without vacuum breach. A contact resistance between the substrate or the first material layer and the second material layer can be reduced, specifically since a reduced amount of oxidized material or even no oxidized material is present at the contact interface between the substrate or the first material layer and the second material layer.

[0088] While the foregoing is directed to embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

1. Method for vacuum processing of a substrate, comprising: irradiating a substrate surface or a surface of a first material layer on the substrate with ions using an ion etch source provided in a processing region while the substrate is moved through the processing region along a transportation path; moving the substrate along the transportation path into a deposition region; and depositing at least one second material layer over the substrate surface or over the first material layer while the substrate is stationary.

2. The method of claim 1, wherein the ion etch source is moving or stationary while the substrate surface or the surface of the first material layer is irradiated with the ions.

3. Method for vacuum processing of a substrate, comprising: moving an ion etch source provided in a processing region with respect to a substrate provided on a transportation path; irradiating a substrate surface or a surface of a first material layer on the substrate with ions provided by the ion etch source while the ion etch source is moved; moving the substrate along the transportation path into a deposition region; and depositing at least one second material layer over the substrate surface or over the first material layer.

4. The method of any one of claims 1 to 3, wherein the ion etch source is a linear ion etch source.

5. The method of any one of claims 1 to 4, further including: depositing the first material layer over the substrate surface.

6. The method of claim 2 or 3, wherein moving the ion etch source includes a moving in at least one of a first direction parallel to the transportation path and a second direction perpendicular to the transportation path.

7. The method of claim 6, wherein the ion etch source is moved sequentially or simultaneously in the first direction and the second direction.

8. The method of any one of claims 3 to 7, wherein the substrate is stationary or is moved along the transportation path while the substrate surface or the surface of the first material layer is irradiated with the ions.

9. The method of any one of claims 3 to 8, wherein the at least one second material layer is deposited over the substrate surface or over the surface of the first material layer while the substrate is stationary.

10. The method of any one of claims 3 to 8, wherein the at least one second material layer is deposited over the substrate surface or over the first material layer while the substrate is moved through the deposition region along the transportation path.

11. The method of any one of claims 1 to 10, wherein the substrate surface or the surface of the first material layer is irradiated with the ions while the substrate is in a vertical orientation.

12. An apparatus for vacuum processing of a substrate, comprising: at least one processing region having at least one ion etch source; at least one deposition region having one or more deposition sources; and a transportation path extending through the at least one processing region and the at least one deposition region, wherein the apparatus is configured to irradiate a substrate surface or a surface of a first material layer on the substrate with ions provided by the at least one ion etch source while the substrate passes the at least one ion etch source, and wherein the apparatus is configured to deposit at least one second material layer over the substrate surface or over the first material layer while the substrate is stationary.

13. The apparatus of claim 12, further including a drive configured to move the at least one ion etch source with respect to the transportation path.

14. An apparatus for vacuum processing of a substrate, comprising: at least one processing region having at least one ion etch source; at least one deposition region having one or more deposition sources; a transportation path extending through the at least one processing region and the at least one deposition region; and a drive configured to move the at least one ion etch source with respect to the transportation path.

15. The apparatus of claim 14, wherein the apparatus is configured to irradiate a

5 substrate surface or a surface of a first material layer on the substrate with ions provided by the at least one ion etch source while the substrate passes the at least one ion etch source or while the substrate is stationary on the transportation path.

16. The apparatus of any one of claims 12 to 15, wherein:

10 the at least one processing region includes two or more processing regions each having one or more ion etch sources; and/or the at least one deposition region includes two or more deposition regions each having one or more deposition sources.

15 17. The apparatus of any one of claims 12 to 16, wherein the ion etch source is a linear ion etch source.