WO2018106196A1 - Anticontamination membrane - Google Patents

Abstract

An anticontamination membrane for application in a machine for prolonging the operational life of the machine which comprises a substrate and a target material deposited thereon. The substrate can be produced by sputtering, electrolysis, evaporating and laser.

Description

ANTICONTAMINATION MEMBRANE

[0001 ] The present application claims a priority date of Singapore patent application with a title of Thin Film Deposition System and Sputtering Process having an application number of 10201 700127P and a filing date of 06 January 2017. All content or relevant subject matter of the priority application is hereby incorporated entirely or wherever appropriate by reference.

[0002] The present application relates to an anticontamination membrane for thin film deposition. The application also relates to methods for making, modifying, installing, assembling, maintaining, removing, replacing, recycling and using the anticontamination membrane for thin film deposition.

[0003] [0004] A thin film is a layer of sheet material ranging from fractions of a nanometer or monolayer to several micrometers in thickness. Controlled synthesis of materials as thin films is known as thin film deposition process, which is a fundamental step in many manufacturing processes. Sputter deposition is one type of the thin film deposition process, which is a Physical Vapour Deposition (PVD) method by sputtering, adopted for producing thin films in electrodes and diffusion barriers of integrated circuits, magnetic thin films for magnetic recording media, and indium-tin oxide (ITO) transparent conductive films for liquid crystal display units.

[0005] Known techniques of sputter deposition have shortcoming of accumulating coarse particulates, commonly known as "particles", on resulting films. The "particles" are clustered minute or fine particulates that built up on a substrate. The particles often grow to sizes as large as several microns in diameter, and the particles' accumulation on the substrate, for example, of an LSI (Large-Scale Integration circuits) could cause shorting of interconnections, disconnection, or other trouble, which leads to an increased percentage of rejected products.

[0006] [0007] The particles are primarily caused by thin film deposition equipment, which largely come from film deposited onto and then peeled off from surroundings of the substrate and inner walls (e.g. chamber walls), shutters, shield plates, and other parts of the thin film deposition equipment. The particles are scattered in broken state and pile up on the substrate, constituting a major contaminant source. However, the inner walls of the thin film deposition equipment, in reality, are very difficult to keep clean. Complete cleaning of the inner walls typically takes long time, and yet the inner walls and devices inside the thin film deposition equipment sometimes are practically inaccessible by cleaners (i.e. cleaning technicians). A countermeasure to reduce the coarse particulates on the inner walls is to physically roughen the inner walls, which are most susceptible to contamination, e.g., by spray coating with metal in advance, so as to secure or capture the deposits inseparably in place. The countermeasure calls for elaborate, scrupulous maintenance of the equipment, and still the anti-peeling effect upon the deposits is quite low. To overcome these difficulties, anticontamination materials in the form of disposable foils have been developed. It was considered that if such disposable foils were affixed to the inner walls beforehand, and removed after the formation (i.e. deposition) of a thin film on a substrate, the inner walls could be maintained clean. [0008] These disposable foils have, however, been found to possess a fatal defect in common. The film-forming substance deposited on the foils mounted in place are liable to come off rather easily, with the result that the formation of particles on the film deposited onto the substrate still occurred as before. Experience has revealed that in these disposable foils, the thicker the layer of the film-forming substance thereon, the more frequently the peeling-off phenomenon from the disposable foil occurs. It has also been found that the phenomenon is liable to occur specially when the film product to be deposited is a ceramic such as silicide or ITO. A remedy to preclude the separation is frequent replacement of the foils, which interrupts and seriously reduces the operation efficiency of thin film deposition. Another problem presented is that during thin film formation by vapour growth, the quality of the film being formed on the substrate is made non-uniform due to the fact that many contaminants flying from around the substrate, especially accompanied with the formation of many particles.

[0009] Under the circumstances there has been a strong demand for an effective means for covering the inner walls of thin film deposition equipment and preventing the particle formation on the inner walls.

[0010] The present application aims to provide one or more new and useful foils for thin film deposition. The present application further aims to provide one or more new and useful particle getters (also known as getter) with the one or more foils for thin film deposition. The application also aims to present new and useful methods for making, modifying, installing, maintaining, removing, recycling, replacing and using the one or more foils for thin film deposition. Essential features of the relevant inventions are provided by one or more independent claims, whilst advantageous features are presented by their respective dependent claims. The foil is alternatively known as a film, a sheet or a thin piece of material that is sometimes flexible, pliable or deformable.

[001 1 ] According to a first aspect, the present application provides an anticontamination membrane (e.g. silicide film) for thin film deposition process (e.g. sputtering process). The anticontamination membrane is alternatively known as anti-contaminating membrane, anticontamination film, anti-contamination sheet, anticontamination layer, anticontamination skin, anticontamination peel or anticontamination means. The anticontamination membrane comprises a flexible sheet material or sheet material for capturing scattered ions, such as positively charged Argon ions or particles in a vacuum chamber. The flexible sheet material is operable or configured to keep its integrity substantially throughout one or more cycles of the thin film deposition process, such as by withstanding more than 300°C, 360°C, 400°C, 465°C, 500°C, 545°C, 600°C, 668°C, 700°C, 763°C, 800°C, 857°C, 900°C, 963°C or higher, whether in vacuum (e.g. inside thin film deposition chamber) or air. The integrity includes structural, chemical composition, shape, size, surface texture, colour, some performance characteristics and other physical or chemical properties. For example, the integrity includes one or more of these indicators, known as structural, chemical composition, shape, size, surface texture, colour, some performance characteristics and other physical or chemical properties. For example, the integrity is preserved if the anticontamination membrane does not peel off, deform, shrink or change colour on an internal wall of a sputtering chamber, after one or more sputtering process. Moreover, the anticontamination membrane does not release or discharge contaminants (e.g. ions, gas particles) under cyclic or continuous exposure to high temperatures or electric charges (e.g. positively charged as anode).

[0012] The anticontamination membrane optionally further comprises one or more base sheets (e.g. composite materials), base structures (wire mesh), substrates (e.g. sandwich structure) and coatings, platings (i.e. plating layers, such as gold plating, silver plating), laminated materials, adhesives, which are harmless or do not release harmful particles if exposed during a thin film vapour deposition process. The anticontamination membrane optionally includes one or more ferrous foils (e.g. electrolytic iron foil) or ferroalloys (ferrous alloy) foils. Different or similar materials (substances) are optionally employed as coatings on an electrolytic nickel foil, provided that combined use or mixing does not constitute a source of contamination during manufacturing processes (e.g. puttering process). For example, a nickel foil is optionally coated with one of the metals constituting an alloy, or tungsten silicide-coated nickel foil is optionally used for the deposition of molybdenum silicide.

[0013] The flexible sheet material may comprise one or more layers of metal (e.g. transition metal or post-transition metal, which may be fully or partially exposed. Alloy of the metal or metal alloy may further be adopted for providing or constructing the flexible sheet material. Especially, the metal includes one or more ferromagnetic materials (also known as ferromagnets) that may be used in their substantially pure form or alloy. One example of the ferromagnetic materials is nickel, whether in a substantially pure or alloy form.

[0014] The flexible sheet material can comprise a substantially pure material, an oxide of the material or a combination of both. The metal (e.g. nickel or Ni with atomic number 28 as 28Ni) can exist at the flexible sheet material in a substantially pure form, known as having purity of more than 90%, 95%, 99%, 99.9%, 99.995% or even higher. A pure metal that is substantially free from impurity or contaminants is suitable for the sputtering process, which is sensitive to contamination. For instance, the layer of metal comprises a nickel foil of purity more than 50%, 85& or 99.9%, which appears lustrous, metallic, and silver with a gold tinge in room temperature and ambient environment. An embodiment of a relevant invention provides a nickel foil that has a purity of more than 99.9% of nickel material, and a surface of the nickel foil is oxidised. Oxidised nickel includes NiO (bunsenite), N12O3 and N1O2. Other examples of the metal include a pure tin (Sn) foil as rolled, a pure Zr (Zirconium) foil as rolled, a pure Al (aluminium) foil as rolled, a SUS304 stainless steel foil, a pure copper (Cu) foil as rolled, a tungsten foil or a molybdenum (Mo) foil.

[0015] The flexible sheet material may further comprise one or more roughened surfaces (e.g. mat, matt or matte surface, uneven surface, corrugated surface). A surface roughness Ra of the flexible sheet material at its oxidised surface is from 1 .Ομιη to 50μιη, preferably 3.0μιη to 20μιη or preferably from 5.0μιη to Ι Ο.Ομιτι. Alternatively speaking, a surface roughness Ra of the flexible sheet material at its oxidised surface is from 1 .0 μιη to 5.0 μιη, or preferably from 2.0 μιη to 4.0 μιη.

[0016] The one or more roughened surfaces can comprise an electrolytically treated surface (e.g. electrolytic nickel foil or surface), an oxidised surface, or both. The one or more roughened surfaces can also comprise a sand blasted surface. The one or more roughened surfaces can additionally comprise a laser or laser beam treated surface.

[0017] The roughened surface can comprise an uneven surface, which include fine grains, corrugation, irregularities, embossing features, indentations or a combination of any of these features.

[0018] Embodiments of the present application or the uneven surface comprises protrusions (e.g. embossing or embossed feature, protuberance), indentations, or a combination of both the protrusions and indentations. For example, respective protrusions and indentations (i.e. depressions, recesses, dimples and valleys) are next to each other, forming an uneven surface with grains, whether in regular or irregular patterns, lineally aligned or tessellated. [0019] The flexible sheet material may have a thickness from 1 μιη to 1 mm substantially. For example, the flexible sheet material has a uniform thickness of 10 μιη to 750μιη, a uniform thickness of 15 μιη to 550μιη, a uniform thickness of 18 μιη to 300μιη, a uniform thickness of 30 μιη to 200μιη, a uniform thickness of 40 μιη to 10Ομιη or a combination of any of these.

[0020] The flexible sheet material can be disposable or recyclable. For example, the flexible sheet material is disposed after going through a predetermined number (e.g. 10 times, 50 times, 100 times, 500 times) of sputtering process in a vacuum chamber. For instance, the flexible sheet material is cleaned or processed (e.g. by electrolytic process as reconditioned) after undergoing some cycles of thin film deposition processes. The cleaned or processed flexible sheet material is reused for the thin film deposition process after being cleaned or reconditioned.

[0021 ] The anticontamination membrane may comprise a predetermined profile (e.g. shape, size, boundaries) for being affixed to a thin film deposition equipment. For example, the anticontamination membrane is provided in the form of a roll, similar to that of an aluminium foil (i.e. misnomer tin foil). Of course, the anticontamination membrane alternatively has a rectangular shape, a square shape, a circular or round or round shape, an oval shape or a combination of any of these shapes.

[0022] The present application further provides a thin film deposition equipment (e.g. system or device for thin film vapour growth), which has vacuum chamber or a sputtering chamber. The thin film deposition equipment or equipment comprises a shield (e.g. anode cone, shutter, substrate shield, target shield) that has one or more portions of the shield's surface covered by the anticontamination membrane. For example, an inner surface of a wall or an inner wall surface of the chamber is partially or fully covered by the anticontamination membrane substantially. The thin film deposition equipment optionally further comprises a holder (also known as retainer) for fastening a substrate for film growth and one or more sputtering sources (e.g. magnetron) for confining charged plasma particles close to a surface of a sputter target. The shield comprises a vessel capable of being vacuumed or hermetically sealed, which has a wall for enclosing the holder and the one or more sputtering sources. One or more portions of an inner surface of a wall of the vessel is covered by the anticontamination membrane.

[0023] In some cases, the anticontamination membrane is detachably affixed to an inner surface of the vessel. In some other cases, the one or more portions of the equipment or an inner surface of the wall comprises a surface or first inner surface covered by a first anticontamination membrane, and a second surface or inner surface covered by a second anticontamination membrane. In the words, parts of thin film deposition equipment or equipment is covered by multiple pieces of anticontamination membranes, which optionally have different profiles, product specifications, performance indicators or other properties. Areas or surfaces that require stronger contaminant absorptions are covered or enwrapped with the anticontamination membrane with better performance. Areas or surfaces that are exposed to less contaminants are reused, recycled, or used with less number of cycles of thin film deposition processes.

[0024] According to a second aspect, the present application provides a method for making an anticontamination membrane for a thin film deposition process. The method comprises a first step of providing a flexible sheet material for capturing scattered ions; a second step of exposing at least one portion of the flexible sheet material; a third step of roughening of a surface of the one or more portions of the flexible sheet material; and a fourth step of detaching the at least one portion from the flexible sheet material. Some of these steps are possibly combined, divided or changed in sequence. For example, the step of a second step of exposing the one or more portions of the flexible sheet material, and the step of roughening of the surface of the one or more portions of the flexible sheet material together by subjecting the flexible sheet material to one or more cycles of electrolysis process. The anticontamination membrane facilitates efficient and high quality thin film deposition processes because the anticontamination membrane absorbs or traps errant particulates effectively over a prolonged process, even under high or cyclic temperature.

[0025] The step of roughening of the surface of the one or more portions of the flexible sheet material can comprise a step of treating the surface by an electrolytic process or electrolysis. The electrolytic process or electrolysis is able to provide uniform roughening surface whose surface roughness can be accurately or precisely regulated.

[0026] The step of roughening of the surface of the one or more portions of the flexible sheet material may comprise a step of creating one or more surface structures of the surface of the one or more portions of the flexible sheet material. The one or more surface textures include grooves, depressions, embossing or any other visible or invisible surface textures. [0027] The method can comprise a step of oxidising the surface of the one or more portions of the flexible sheet material. The method can also comprise another step of subjecting the surface of the one or more portions of the flexible sheet material to an electrolysis process, which produces an electrolytic surface (e.g. for copper, nickel, iron) or electrolytic material (e.g. electrolytic copper, electrolytic nickel, electrolytic iron).

[0028] The method may additionally comprise a step of attaching a base sheet to the flexible sheet material. The base sheet comprises a base structure, a substrate, a coating layer (i.e. coating), a plating layer (e.g. plating), a laminated material or an adhesive layer, which is harmless or does not release harmful particles to thin film vapour deposition process. The base sheet provides additional structure support to the anticontamination membrane against peeling, or cyclic heating and cooling.

[0029] According to a third aspect, the present application provides a method of using anticontamination membrane for thin film deposition process. The method comprises a first step of offering an anticontamination membrane or the anticontamination membrane as mentioned earlier; a second step of providing a thin film deposition equipment; and a third step of detachably attaching (e.g. spot welding or precision spot welding) the anticontamination membrane to a wall of the thin film deposition equipment. Some of these steps are optionally combined, divided or changed in sequence. The method of using anticontamination membrane provides opportunities to remove an exhausted or used anticontamination membrane, and attaching a new anticontamination membrane to a wall of a thin film deposition equipment (e.g. anode cone, getter or particle getter). The used anticontamination membrane is possible to be recycled (e.g. cleaned or reconditioned) such that a recycled anticontamination membrane becomes useful for a thin film deposition process, or other processes.

[0030] The method can further comprise a step of performing thin film deposition process (e.g. sputtering), which utilises the anticontamination membrane. After some cycles of thin film deposition processes, the used anticontamination membrane is sometimes removed from a wall surface of a thin deposition equipment, possibly disposed subsequently. The used anticontamination membrane is possible to be replaced by a newly manufactured, a fresh (i.e. not used before), a cleaned or a reconditioned anticontamination membrane.

[0031 ] The method may further comprise a step of treating (e.g. cleaning) the wall before or after attaching the anticontamination membrane. The wall (e.g. an inner wall or surface of the thin film deposition equipment) is possibly made rough, oxidised, sand blasted or buffered for affixing the anticontamination membrane with improved adhesion.

[0032] Embodiments of the method additionally comprises a step of making available or attaching (e.g. affixing) a base sheet to the flexible sheet material in order to offer anticontamination membrane. The base sheet enhances structural integrity or lowers cost of the anticontamination membrane. For example, the anticontamination membrane comprises a metal sheet (e.g. stainless steel foil) coated with a nickel layer. The metal sheet and/or the nickel layer are possibly subjected to other processes (e.g. oxidising process, electrolysis process) before being attached to an inner wall of vacuum chamber for thin film deposition.

[0033] According to fourth aspect, the present application provides an anticontamination membrane (i.e. anticontamination) means that comprises a substrate (e.g. base sheet) for supporting the target material and a target material on the substrate for producing an irregular surface. The target material and the substrate can be the same material (e.g. nickel). One or more surfaces (e.g. both surfaces at opposite sides) of the substrate may irregular or uneven. The substrate can be pliable or flexible for applying onto one or more non-flat surfaces or areas of interest (e.g. machines or other parts where applicable). [0034] According to a fifth aspect, the present application provides a method for producing an anticontamination membrane by sputtering. The method comprises a first step of securing the substrate on a holder (i.e. retainer); a second step of placing the target material on one or more ejectors (e.g. magnetron); a third step of evacuating a chamber that encloses the holder; a fourth step of in-filling of a process gas or inert gas (e.g. Argon) into the chamber; a fifth step of energising the one or more ejectors creating a magnetic flux. Some of these method steps are optionally combined, divided or changed in sequence.

[0035] According to a sixth aspect, the present application provides a method for producing an anticontamination membrane by electrolysis. The method comprises a first step of treating the surface of the substrate (e.g. nickel foil); a second step of immersing the substrate in an electrolyte solution (e.g. nickel sulphate and ammonium sulphate); a third step of curing the substrate with the newly formed surface in another electrolyte solution (e.g. nickel sulphate, boric acid and nickel chloride); and a fourth step of baking the substrate in the oven. Some of these method steps are optionally combined, divided or changed in sequence.

[0036] According to a seventh step, the present application provides a method for producing an anticontamination membrane by evaporation. The method comprises a first step of attaching the substrate onto the holder; a second step of heating the target material (e.g. nickel) to its boiling point (i.e. 2,730^QC); and a third step of evaporating the target material (e.g. nickel) to the substrate (e.g. nickel foil) at the holder (i.e. retainer). Some of these method steps are optionally combined, divided or changed in sequence.

[0037] According to an eighth step, the present application provides a method for producing an anti-contaminating means by laser. The method comprises a first step of placing a substrate (e.g. nickel foil) onto the porous metal on the chuck; a second step of placing the master foil above the substrate; a third step of placing the polyimide foil above the master foil; a fourth step of activating the vacuum; and a fifth step of projecting the laser onto substrate, the master foil or both. Some of these method steps are optionally combined, divided or changed in sequence. A plurality of the substrates are possibly arranged in a vertical orientation with a divider (e.g. non-metallic materials such as paper) in-between each substrate. Some of these method steps are optionally combined, divided or changed in sequence. The substrate possible to be laid on surfaces of the parts of interest for preservation. The method may further utilise mechanised means to convey the substrate, such as by end effector grasping or vacuum. [0038] According to a ninth aspect, the present application provides a metal foil for thin film deposition. The foil comprises a ferromagnetic material (e.g. iron, cobalt, nickel, and gadolinium) for attaching to a sputtering equipment during sputter deposition and for trapping particles scattered flying from a vapour phase growth procedure. The metal foil has a thickness of about 0.1 millimetre or less, and a surface of the foil is roughened. The ferromagnetic material comprises nickel (Ni) material or nickel alloy, such as permalloy, elinvar, invar, nickel iron, nickel cast iron, nickel brasses, nickel bronzes, alloys with copper, chromium, aluminium, lead, cobalt, silver, and gold (e.g. Inconel, Incoloy, Monel, Nimonic). The roughened surface can be electrolysed. The metal foil may comprise protuberances or embossments on the electrolysed side or surface. The protuberances can comprise fine grains imperceptible to by a naked eye, but perceived as matt surface, or have a surface roughness, Ra, in the range of 05 to 20 pm. Some the fine grains as protuberances or embossments have sizes of Ι ΟΟμιτι or less. One or more portions of the metal foil may be oxidised. The metal foil can be detachable (e.g. a non-splitting sheet) from parts of thin film deposition equipment (e.g. a particle getter) for disposal, and the metal foil is accordingly known as a disposable foil. [0039] According to a tenth aspect, the present application provides a sputter deposition equipment that has one or more particle getters. At least one of the particle getters is connected to an anode of an electrical power supply; and the particle getter has a cone shape or any shape any shape for fitting the parts of the equipment.

[0040] According to a ninth aspect, the present application provides a method for making a foil for thin film deposition. The method comprises a first step of providing a ferromagnetic material (e.g. iron, cobalt, nickel, and gadolinium); and a second step of attaching the ferromagnetic material to the parts of thin film deposition equipment for capturing scattered particles during the thin film deposition. The step of attaching the ferromagnetic material to the parts of thin film deposition equipment can comprises welding (e.g. precision spot welding) the ferromagnetic material to the parts of thin film deposition equipment. The method may further comprise a step of electrolysing the ferromagnetic material, possibly before attaching the ferromagnetic material to the parts of thin film deposition equipment (e.g. sputter deposition equipment). The method can further comprise a step of roughening the ferromagnetic material before attaching the ferromagnetic material to the parts of thin film deposition equipment. The method may further comprise a step of embossing the ferromagnetic material (before attaching the ferromagnetic material to the parts of thin film deposition equipment.

[0041 ] The one or more foils can include one or more nickel foils that can be used in copper and non-copper thin film deposition equipment and sputtering process. With a particle getter covered or made with the nickel foil, scattered particles will be readily caught by the particle getter during a thin film deposition sputtering process. The nickel foil covers a particle getter which form a nickel particle getter for non-copper thin film deposition process. The nickel particle getter provides better absorption of particles and last longer for the thin film deposition process. [0042] The one or more nickel foils have round shape emboss pattern such that surface areas of the one or more nickels foil are extended, which may be used in non-copper thin film deposition process. Surface of the nickel foil has absorption ability better than that of copper foil such that the nickel foil is able to catch more particles during the thin film deposition process. The nickel foil is further able to withstand high temperature. For example, melting point of nickel is 1 ,455°C, which is 370°C higher than that of copper. Nickel material also has smaller thermal expansion rate than that of copper. Typically, the maximum working temperature of a nickel foil is about 600°C, which is about 200°C higher than that of copper.

[0043] [0044] The nickel foil for thin film deposition provides better absorption of deposition and particle, better durability and longer lifetime in thin film deposition process. The nickel foil is especially suitable for non-copper thin film deposition process. Due to the excellent performance of nickel foil, the nickel foil for thin film deposition provides more opportunities of developing advanced semiconductor manufacturing process.

[0045] The present application provides an anticontamination membrane that includes:

1 . a treated electrolytic nickel foil;

2. a treated electrolytic nickel foil coated with a material which is the same as or is harmless and similar to the material to be deposited as a thin film by vapour phase growth onto the substrate;

3. a corrugated metal foil, and

4. a metal foil formed with a plurality of irregularities, namely many recesses and protrusions by embossing. [0046] The present application further provides an equipment for thin film deposition by vapour phase growth characterized in that the contamination of the devices and the formation of particles in the deposited thin film inside the equipment are prevented by the provision of an anticontamination means which is chosen from among (1 ) an electrolytic nickel foil or a nickel foil having a fine-grained thin layer of nickel or/and nickel oxide formed by nickel plating on the matte surface of the nickel foil, (2) a nickel or an electrolytic nickel foil having a fine-grained thin layer of nickel or/and nickel oxide formed by nickel plating on the matte surface of the foil, and coated with a material which is the same as or is harmless and similar to the material to be deposited as a thin film by vapour phase growth onto the substrate, (3) a corrugated nickel foil, and (4) a nickel foil formed with a plurality of irregularities by embossing. The application additionally provides an anticontamination means used in a thin film vapour deposition equipment which is selected from the group of said (1 ) to (4). The application further provides a method for preventing contamination of devices and formation of particles in the deposited thin film inside the equipment by using said anticontamination membrane. [0047] According to a twelfth aspect, the present application provides a system or device for thin film deposition by vapour phase growth. The system has an anticontamination means fitted therein. The anticontamination means includes a treated electrolytic Nickel foil that has fine grains of Nickel, Nickel oxide or a mixture of Nickel and Nickel oxide, which are precipitated by Nickel plating on numerous protuberances of a matte surface of an electrolytic Nickel foil. Contamination of devices and formation of particles a deposited thin film inside the system are possibly prevented, minimised or alleviated. The electrolytic Nickel foil can have on the matte surface thereof a surface roughness, Ra, in the range of 5 to 10 pm. One side of the treated electrolytic Nickel foil (known as foil) may have fine grains therein, which are oriented as a side for trapping scattered flying particles from a vapour phase growth procedure. The foil can be a disposable electrolytic Nickel foil, and the system can be a sputtering system.

[0048] Embodiments of the system have an anticontamination means fitted therein. The anticontamination means comprises a treated electrolytic Nickel foil having fine grains of Nickel, Nickel oxide or a mixture of Nickel and Nickel oxide precipitated by Nickel plating on numerous protuberances of a matte surface of an electrolytic Nickel foil. The foil is further possibly coated with a material, which is the same as or is harmless and similar to the material to be deposited as a thin film by vapour growth on a substrate (e.g. silicon wafer), whereby the contamination of devices and the formation of particles in the deposited thin film inside the system are often prevented. The electrolytic Nickel foil can have on its matte surface thereof a surface roughness, Ra, in the range of 5 to 10pm substantially. A side of the foil may have the fine grained thereon is oriented as a side for trapping or capturing particles scattered flying from a vapour growth procedure.

[0049] The Nickel foil can have fine grains of Nickel, Nickel oxide or a mixture of Nickel and Nickel oxide precipitated by Nickel plating on a surface of the Nickel foil, with or without coating of a material which is the same as or is harmless and similar to the material to be deposited as a thin film by vapour growth or to a substrate. The anti- contamination means may be spot welded to one or more apparatuses inside the system (e.g. sputtering system) so as to cover them. [0050] [0051 ] The accompanying figures (Figs.) illustrate embodiments and serve to explain principles of the disclosed embodiments. It is to be understood, however, that these figures are presented for purposes of illustration only, and not for defining limits of relevant applications.

Fig. 1 illustrates an application of a nickel foil in a chamber;

Fig. 2 illustrates a schematic of an embossing process of the nickel foil by electrolysis;

Fig. 3 illustrates a schematic diagram of an embossing process of the nickel foil by deposition; and

Fig. 4 illustrates a schematic of a cross section of a laser embossing set-up.

[0052] Exemplary, non-limiting embodiment of the present application will now be described with references to the above-mentioned figure. [0053] Fig. 1 illustrates an application of a nickel foil in a chamber. The chamber is a sputtering chamber 100. The sputtering chamber 100 is shown with a hinged semi- spherical door removed which has a thick concentric highly polished steel wall. Along an inner surface of the concentric steel wall is overlaid by an anticontamination membrane 102 as shown by a shaded part. The anticontamination membrane (i.e. anticontamination layer) 102 is substantially made of nickel with purity of more than 99.9%, hence is also known as a nickel foil.

[0054] In the sputtering chamber 100 are three magnetrons located at the base of the concentric wall. Each magnetron 104 is supported by a stand whilst the opposite face is pointing in the direction of a holder 108. The opposite face is where a target material 106 is placed thereon. The three magnetrons 104 are placed equidistant laterally in a triangle formation. The pitch of the magnetrons 104 can be independently adjusted manually or remotely via a microcontroller.

[0055] The holder 108 is located at the opposite side of the magnetrons 104, in other words, at a top area proximal to the concentric wall. The holder 108 is then attached to a rotating spindle 1 10. The rotating spindle 1 10 is attached to the concentric wall at a top end. The holder is somehow suspended in the sputtering chamber 100 like an overhanging fan. The holder 108 itself has at least two gripping arm 1 12 that is disposed at a surface facing the three magnetrons 104. The gripping arms 1 12 clasp on to a substrate 1 14.

[0056] At the opposite end of the door of the sputtering chamber 100 are three valves aligned in a straight horizontal line bias slightly to the top section. A gas inlet valve 1 16 on a left position, an evacuation valve 1 18 at a centre position and a processed gas inlet valve 120 on a right position.

[0057] Fig. 2 illustrates a schematic of an embossing process of a nickel foil 142 by electrolysis 140. The nickel foil 142 is shown as a circular disc with a thickness of one millimetre (1 mm) and a diameter of about a hundred millimetres (100 mm). A top left schematic shows the circular nickel foil 142 from a side view and from a three- dimensional view. A first arrow 166 points thereafter to a first step. The first step is a surface treatment 174 of the nickel foil 142. Thereafter, a second arrow 168 points to a second step of providing an irregular surface treatment 176. Thereafter, a third arrow 170 points to a third step of curing 178. Thereafter, a fourth arrow 172 points to a fourth step of hardening or strengthening 180.

[0058] In detail, the nickel foil 142 is immersed in a first container 144 which contains hydrochloric acid 146, HCI. The hydrochloric acid-treated nickel foil 148 is then transferred to a second container 150 which contains a solution of nickel sulphate and ammonium sulphate 152.

[0059] The second container 150 also has two metallic electrodes 154 inserted into the solution of nickel sulphate, NiS04 and ammonium sulphate, (NH4)2804 152. The two electrodes 154 are connected to a DC (direct current) electrical power supply (not shown). The DC electrical power supply has a positive polarity and a negative polarity. The positive polarity is connected to the first electrode 154 on a left side of the second container 150. The negative polarity is connected to the second electrode 156 on a right side of the second container 150. The two electrodes 154,156 are supported by a holder (not shown) that suspends the two electrodes 154,146 in the solution. The nickel foil 142 acquires an irregular surface when an electrical potential is applied across the electrodes 154,156 immersed in the solution. The solution is an electrolyte that produces an electrically conducting solution when dissolved in a polar solvent, for example water (H2O) which is mixed with the solution of nickel sulphate and ammonium sulphate 152. The dissolved electrolyte separates into cations and anions, which disperse uniformly through the solvent. Electrically, the solution is neutral. If the electric potential is applied to the solution, the cations of the solution are drawn to the cathode (electrode with positive polarity) that has an abundance of electrons, while the anions are drawn to the anode (i.e. electrode with negative polarity) that has a deficit of electrons. The movement of anions and cations in opposite directions within the solution amounts to a current.

[0060] Nickel sulphate is a highly soluble blue-coloured salt which is mainly used for electroplating. The aqueous solution of nickel sulphate reacts with sodium carbonate to precipitate nickel carbonate, a precursor to nickel-based catalysts and pigments. The addition of ammonium sulphate to concentrated aqueous solutions of nickel sulphate precipitates Νί(ΝΗ4)2(80 -8Η2θ or known as ammonium nickel sulphate. This blue- colored solid is analogous to Mohr's salt, Fe(NH4)2(S04)2-6H20 is also known as ammonium iron sulphate. A precipitate 158 is formed on the surface of the nickel foil 142 producing the irregular surface. The surfaces include the top surface and the circumference of the nickel foil 142. If, however, the nickel foil 142 were suspended in the solution supported by a holder (not shown), the nickel foil 142 would be completely coated with the precipitate.

[0061 ] The precipitated nickel foil 160 is then transferred to a third container 162 which contains nickel sulphate (N1SO4), boric acid (H3BO3) and nickel chloride, (N1CI2) 164. The third container 162 has another set of electrodes 154,156 connected to a DC electrical supply. The irregular surface of the nickel foil 160 with ammonium nickel sulphate thereon is cured in the third container 162.

[0062] In the electroplating of the nickel foil, boric acid is used as part of a formula. One such known formula calls for about a 1 to 10 ratio of boric acid (H3BO3) to nickel sulphate (N1SO4), a very small portion of sodium lauryl sulfate and a small portion of sulphuric acid (H2SO4). Nickel chloride solution is used for electroplating nickel onto other metal items. A fresh layer of nickel is coated onto the surface of the irregular surface of the nickel foil. The fresh layer of nickel coated nickel foil is then baked in an oven 182 for hardening or strengthening! 80. [0063] Fig. 3 illustrates a schematic diagram of an embossing process of the nickel foil 142 by deposition 200. The nickel foil 142 is the substrate 1 14 which is held by a holder (not shown) via an air suction. The holder (i.e. retainer) is attached to a rotating spindle 1 10. The one end of the rotating spindle 1 10 is attached to a stepper motor 208. An evaporative source 202 is positioned beneath the substrate 1 14. The nickel foil 142 is tilted facing the evaporative source 202. The evaporative source 202 contains nickel whereby the evaporated vapour flux 204 (shown by the three directional block arrows pointing upwards) ascends to the surface of the nickel foil 142 above. The vapour flux 204 condenses on the surface of the nickel foil 142 and forms irregular tilted columns 210 as shown in a closed-up view as distinguished by a circular broken line. The irregularity 210 is caused by the random arrival of the vapour flux 204 on the surface (nickel foil). Adjacent columns 210 are unequal in size and as a result some columns 210 block the adjacent columns 210 from the vapour flux 204 causing a decrease in the latter's growth. Deposition of nickel on the substrate 1 14 is performed in a vacuum chamber (not shown). The base pressure of the vacuum chamber is about 6.7 x 10^"5 Pascal. The thickness of the nickel deposition is about one micron (1 μιη). The thickness of the nickel deposit can be varied by having longer exposure to the evaporation source 202. [0064] Fig. 4 illustrates a schematic of a cross section of a laser embossing 250 set-up. A solid nickel piece with a diameter of about twenty millimeters (20 mm) and a thickness in the range of one to two millimeters (1 ~2 mm) is used as a work piece 252. The work piece 252 is prepared by sawing, soft annealing, and subsequent polishing of the surface. A nickel foil with a thickness of about three microns (3 pm) is used as a master foil 254 which acts as a stencil. The master foil 254 has a grid of square perforations of about 100 μιη x 100 μιη. A gap of two microns (2 μιη) between adjacent squares.

[0065] The solid nickel work piece 252 is placed onto a vacuum chuck 256. Then the one nickel foil (master foil) 254 is overlaid on the work piece 252. A twenty-five micron (25 μιη) thick polyimide foil 258 covers the vacuum chuck 256, the master foil 254, and the work piece 252. By turning on the vacuum pump 266, the polyimide foil 258 seals the chuck 256 and subsequently the polyimide foil 258 presses the nickel foil 254 and the work piece 252 firmly together. The evacuated air travels through a vacuum chamber 264 by the air suction of the vacuum pump 266. The polyimide foil 258 is then irradiated with a Krypton Fluoride excimer (exciplex) laser 260. The polyimide foil 258 is a synthetic resin which exhibits high heat resistant property.

[0066] The Krypton Fluoride (KrF) excimer (exciplex) laser 260 with a pulse length of twenty-five nanoseconds (25 ns) and a wavelength of two hundred and forty-eight nanometers (248 nm), which is embedded in a laser workstation, is used for laser irradiation. The workstation furthermore comprises a beam shaping and homogenizing optics which provides a flat top beam profile at a laser spot area of 100 μιη x 100 μιη. The scanning of the laser beam across the polyimide surface is performed with a program-controlled x-y-z stage. The repetition rate of the laser was fixed at a frequency value of a hundred Hertz (100 Hz).

[0067] The size of the area patterned by micro-embossing is limited by the laser spot size. The number of pulses which are applied onto one point to create an impression is estimated to be about more than twenty times. With this pulse number the polyimide foil 258 is not drilled through and a thin polyimide layer of about 1 μιη remains which is sufficient to protect the upper nickel foil 254 from the thermal impact of the laser pulses. Therefore, after the embossing process the polyimide foil 258 with all contaminations and debris from the laser ablation can simply be removed by taking it away. Hence, contaminations of the work piece 252 or the nickel master foil 254 by debris can be excluded.

[0068] The applied laser pulses were absorbed in the polyimide foil 258 and caused laser ablation of the polyimide foil 258 and the formation of a plasma plume. Shock waves from the expanding plasma and thermal processes provide a momentum sufficient to emboss the structured master foil 254 into the underlying nickel piece 252.

[0069] The object of having an irregular surface of the nickel foil 142 and to lay on the surface of the sputtering chamber 100 is to extend the period of use of the sputtering chamber 100 before the next maintenance. The sputtered nickel foil 142 having the irregular surface is then used to apply onto the walls and parts in the sputtering chamber 100.

[0070] Functionally, the front view of the sputtering chamber 100 as shown in Fig. 1 is constructed with steel to withstand the atmospheric pressure exerted thereon when the internal chamber devoid of air or vacuumed. The cylindrical body and the two semi- spherical ends provide a uniform pressure distribution. Fig. 1 illustrates an application of the nickel foil 142 as well as a process of obtaining the nickel foil 142 by sputtering. [0071 ] In a sputtering process, the sputtering chamber 100 requires a controlled environment which is a vacuumed inner chamber, thus also known as vacuum chamber. The base pressure in the vacuumed inner chamber is about 10^"6 bars. The vacuumed inner chamber provides a cleaned environment free of suspensions and invisible charged ions and particles. Once the sputtering chamber is evacuated of air via the evacuation valve 1 18, Argon gas is filled with through the processed gas inlet 120. Argon is an inert element which is suitable for uses in high-temperature environment like in sputtering. Argon prevents the internal parts from oxidation and burning.

[0072] The magnetrons 104 contain electromagnets which is energized by an electrical current. The electrical source can be from an electrical grid. The electromagnets are coated with water resistant material to prevent corrosion and electrical short circuit. The inner cavity of the magnetrons 104 is filled with water to cool down the sputtering process. The water within can be running water which means that there are conduits that are connected to the magnetron 104 to provide water inflow and water outflow at different positions on the magnetron 104. During the sputtering process, the free electrons continuously hit the Argon atoms to create Argon positive ions. The positively charged Argon ions then collide with the target material 106 on the magnetron 104. The target material 106, nickel is negatively charged which attracts the Argon ions. The attraction causes bombardment of the Argon ions to the nickel ions. The momentum of the bombardment causes the nickel ions to project itself to the substrate 1 14 suspended at the top of the inner chamber. The substrate 1 14 is a nickel foil 142 which is to be coated with the nickel ions making the surface of the nickel foil 142 irregular.

[0073] In Fig. 2, the nickel foil 142 is shown as a circular disc with a thickness of one millimetre (1 mm) and a diameter of about a hundred millimetres (100 mm) is just an example. Having a considerable thickness provides reasonable strength during the embossing or having the irregular surface. A too thin foil makes embossing impracticable. The substrate 1 14 is the nickel foil 142 in Fig. 1 can also be of the same dimension. [0074] The hydrochloric acid 146, HCI in the first container 144 removes impurities on the surface of the nickel foil 142 which is a surface treatment 174 phase. The treated nickel foil 148 or activated nickel foil is then soaked in the second container 150 with electrolyte comprising nickel sulphate and ammonium sulphate 152. Nickel sulphate is used in the electroplating of nickel to the nickel foil 142. The addition of ammonium sulphate produces crystals on the surface of the nickel foil 142. This is the irregular surface treatment phase 176. The roughened nickel foil is then immersed in the third container 162 for strengthening of the roughened surface or curing 178. The final phase is baking in the oven 182 to harden or strengthen 180 the coating.

[0075] Fig. 3 provides a process of evaporating nickel. The evaporated nickel condenses on a cooler surface of the nickel foil 142 above which forms columns 210. The nickel foil 142 is continuously rotated to obtain a uniform distribution of the evaporated nickel from the evaporation source 202 beneath.

[0076] Fig. 4 provides a process of embossing on the nickel foil 142 by using firing a laser beam through a master foil 254 overlaid thereon. The vacuum chamber 264 provides the suction of the nickel foil 142 from the bottom side through the porous metal 262.

[0077] A method of using the anticontamination membrane 102 (i.e. anti-contaminating means or anticontamination means) by a sputtering process comprises the steps of firstly securing the substrate 1 14 on a holder 108. The substrate 1 14 in this case in the nickel foil 142. The holder 108 (i.e. retainer) is attached to a rotating spindle 1 10 driven by a rotating motor 208. Secondly, placing the target material 106 on at least one magnetron 104. The target material 106 is nickel. Thirdly, evacuating the chamber by sucking the air out providing a cleaned and controlled environment. Fourthly, in-filling of the processed gas back into the chamber which is the argon gas. Fifthly, energising the at least one magnetron 104 creating a magnetic flux. The magnetic flux ionises the Argon atoms producing positively charged Argon ions. The Argon ions bombard the target material 106 which is negatively charged ejecting the target material 106 onto the substrate 1 14. Finally, the nickel foil 142 is deposited with the nickel creating the irregular surface. [0078] A method of producing an anti-contaminating means by electrolysis 140 comprises the steps of firstly treating the surface of the nickel foil 142 with hydrolchloric acid 146 for the removal of impurities (oxides or particles). Secondly, immersing the hydrochloric acid-treated nickel foil 148 in a solution of nickel sulphate and ammonium sulphate 152 to produce precipitation 158 on the surface of the nickel foil 142. Thirdly, curing 178 the newly formed surface in a solution of nickel sulphate, boric acid and nickel chloride 164. Steps two and three makes use of electricity passing through electrodes 154,156 to achieve the coating on the surface. Lastly, hardening or strengthening 180 the nickel foil in the oven 182 to harden.

[0079] A method of producing an anti-contaminating means (i.e. anticontamination membrane or anticontamination means) by evaporation 200 comprises the steps of first attaching the nickel foil 142 or the substrate 1 14 onto a holder with rotating spindle 1 10 driven by the stepper motor 208. Secondly, heating a piece of nickel to its boiling point at 2,730^QC causing the evaporation of the nickel to the nickel foil 142 at the holder. The process takes place inside a vacuum chamber that is cleaned and controlled. The parts and the components are to withstand the high temperature demand.

[0080] A method of producing an anti-contaminating means by laser comprises the steps of firstly placing the nickel foil 142 is also known as the work price 252 onto the porous metal 262 on the vacuum chuck 256. The porous metal 262 has perforations allowing the suction of the nickel foil 142 by the vacuum chamber 264 beneath the porous metal 262 (i.e. nickel master foil or master foil). Secondly, placing the nickel master foil 254 above the nickel foil 142. The nickel master foil 254 is perforated. Each perforation is spaced evenly apart from the adjacent perforations. The master foil 254 acts as a stencil for the laser 260 to shoot through and also to protect the nickel foil 142 from being contaminated by the blasted nickel from the nickel foil 142. Thirdly, placing the polyimide foil 258 above the nickel master foil 254. The polyimide foil 258 provides a secure blanket of the underneath layers when the vacuum pump 266 is triggered. The polyimide foil 258 is also tolerant to high temperature. Finally, projecting the laser 260 through the polyimide foil 258, the nickel master foil 254 and hitting the nickel foil 142. The laser 260 hits the nickel foil 142 at a prescribed intensity without making a bore. The points of impact of the laser 260 creates indentations. The impacted points contrast with the non-blasted surface hence creating an irregular surface. [0081 ] A method of packaging the nickel foil, wherein the substrate 1 14 is arranged erected with a divider in-between each substrate 1 14. The divider is non-metallic material for example, paper. Paper is economically viable and environmentally sustainable. The substrates 1 14 can be packed in a packet of twelve inside a hard casing like a Perspex. Alternatively, the hard casing itself has slot compartments to house each substrate 1 14 without physically in contact with the adjacent substrate 1 14. The vertical arrangement ensures that the surface treatment of the substrate 1 14 is not damaged during transportation. [0082] A method of application of the nickel foil 142, wherein the substrate is laid on surfaces of the parts of interest for preservation and spot welded thereon. Typically, the main application of the substrate 1 14 will be on the surfaces of the inner parts of the sputtering chamber 100. The treated substrate 1 14 prolongs the operational life of the sputtering chamber 100 before the next servicing. In spot welding, the different substrates are held together under pressure exerted by electrodes (different from the electrodes used in the electrolysis). The thickness of the substrate 1 14 is approximately 1 mm. The process uses two shaped copper alloy electrodes to concentrate welding current into a small "spot" and to simultaneously clamp the substrates 1 14 together. Forcing a large current through the spot will melt the metal (nickel substrate) and form the weld. The attractive feature of spot welding is that a lot of energy can be delivered to the spot in a very short time (approximately 10-100 milliseconds). That permits the welding to occur without excessive heating of the remainder of the substrates 1 14. The weld is not exposed at the top surface of the adjoining substrates 1 14 to avoid contamination by the copper electrodes.

[0083] The substrate mentioned so far is circular in shape. Further process can be done to shape the circular substrate into other polygonal shapes if required.

[0084] The mentioned coating or deposition processes of the substrate (i.e. nickel foil) are controlled by a controller. The controller comprises a computer, a memory storage, an array of input and output (I/O) ports and connectors and a communication module. The I/O ports and connectors provide connection from the computer to the stepper motor 208, magnetrons 104 and access door in the sputtering chamber 100 of Fig. 1 as well as the evaporation process 200 shown in Fig. 3 and to the laser equipment 250 shown in Fig. 4. The computer provides management of resources and control the connected peripherals as mentioned. The computer and the peripherals are powered by an electrical grid independently. The computer is able to control one single process or all four of the mentioned deposition processes independently. The connection to the peripherals can be through a CAT (Category) 6 Ethernet cable with the corresponding network cards attached on the computer and the peripheral or a serial communication using USB (Universal Serial Bus). The network cards are part of the communication module. Wireless communication between the computer and the peripherals can also be achieved using wireless technology like Wi-Fi (radio frequencies), Bluetooth and Infrared. A typical communication module which comprises wired and wireless connectors and protocols is an Arduino Uno. Additional wireless module can be plugged into the Arduino Uno. The memory storage contains algorithms that controls a rotational rate of the stepper motor 208, an electrical current to the magnetrons 104. There can also be sensors detecting the thickness of the deposition on the substrate 1 14. The outputs of the sensors are fed to the computer for processing by the algorithms. The algorithm based on the sensor feedback can indicate the time for maintenance.

[0085] Take the process of sputtering for example, if the stepper motor 208 were to rotate at fifty rotations per minute with an input electrical current of one Ampere to the magnetrons 104 for a time of one minute, the thickness of the deposition ought to be one micron thick. However, if the feedback provided by the sensor detect a deviation on the thickness of the deposition, it would imply that the sputtering chamber 100 need to be serviced (cleaned). The deviation of the thickness could mean thicker perhaps caused by more unwanted particles sticking to the substrate. The servicing of the sputtering chamber 100 implies replacing the nickel foil 142 which is the nickel foil (the substrate).

[0086] The computer can also control the activation of the electrical current to the electrodes 154,156 as shown in Fig. 2 in the process of electrolysis 140. The computer can control a plurality of motor that elevates and lowers the substrate(s) 1 14 or the electrodes 154,156 into the electrolyte. In mass manufacturing, multiple substrates 1 14 can be put in a basket and lower into the electrolyte for an increased productivity. The placement of the multiple substrates 1 14 into the basket can be done by a plurality of anthropomorphic robotic arm. The anthropomorphic robotic arm is controlled by the computer as well. After each successful treatment of the substrate 1 14, the anthropomorphic robotic arm is programmed to retrieve the basket and transfer to a next station (different container of electrolyte) or to a packaging station for a final packaging. In fact, the anthropomorphic robotic arm can be used on all the different processes. For example, placing the substrate 1 14 on the holder 108 and retrieving by the anthropomorphic robotic arm for sputtering, evaporation and laser embossing. The use of the anthropomorphic robotic arm ensures consistency and control of the output quality of the substrate 1 14. A terminal part of the anthropomorphic robotic arm has a hand-like contraption to grasp onto the substrate 1 14. Alternatively, the terminal part of the anthropomorphic robotic arm has a plurality of suction cup that sucks the substrate onto the cup by using vacuum. The terminal part is also known as an end-effector.

[0087] In conclusion, the object of providing a more durable anti-contamination membrane is achieved by creating an irregular surface membrane. The anti- contamination membrane is specifically nickel which is the choice of material used as it is chemically and mechanically stable when used in application especially in a sputtering chamber 100. Three methods are described to achieve the object of producing an irregular surface nickel to be laid inside the sputtering chamber 100. The nickel foil 142, the substrate 1 14 and the work piece 252 are used interchangeably depending on the context.

[0088] [0089] In the application, unless specified otherwise, the terms "comprising", "comprise", and grammatical variants thereof, intended to represent "open" or "inclusive" language such that they include recited elements but also permit inclusion of additional, non-explicitly recited elements.

[0090] As used herein, the term "about", in the context of concentrations of components of the formulations, typically means +/- 5% of the stated value, more typically +/- 4% of the stated value, more typically +/- 3% of the stated value, more typically, +/- 2% of the stated value, even more typically +/- 1 % of the stated value, and even more typically +/- 0.5% of the stated value.

[0091 ] Throughout this disclosure, certain embodiments may be disclosed in a range format. The description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the disclosed ranges. Accordingly, the description of a range should be considered to have specifically disclosed all the possible sub-ranges as well as individual numerical values within that range. For example, description of a range such as from 1 to 6 should be considered to have specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within that range, for example, 1 , 2, 3, 4, 5, and 6. This applies regardless of the breadth of the range.

[0092] It will be apparent that various other modifications and adaptations of the application will be apparent to the person skilled in the art after reading the foregoing disclosure without departing from the spirit and scope of the application and it is intended that all such modifications and adaptations come within the scope of the appended claims.

Reference Numerals

100 sputtering chamber

102 anticontamination membrane

104 magnetron

106 target material

108 holder

1 10 rotating spindle

1 12 gripping arm

1 14 substrate

1 16 gas inlet valve

1 18 evacuation valve

120 processed gas inlet valve

140 embossing process by electrolysis

142 nickel foil

144 first container

146 hydrochloric acid

148 hydrochloric acid treated nickel foil

150 second container

152 nickel sulphate and ammonium sulphate

154 first electrode

156 second electrode

158 precipitate

160 precipitated nickel foil

162 third container

164 nickel sulphate, boric acid and nickel chloride

166 first arrow

168 second arrow

170 third arrow

172 fourth arrow

174 surface treatment

176 irregular surface treatment

178 curing

180 hardening or strengthening

182 oven 200 embossing process of the nickel foil by deposition

202 evaporative source

204 vapour flux

206 circular broken line

208 stepper motor

210 columns

250 laser embossing

252 work piece

254 master foil

256 vacuum chuck

258 polyimide foil

260 Krypton Fluoride excimer (exciplex) laser

262 porous metal

264 vacuum chamber

266 vacuum pump

Claims

Claims

An anticontamination membrane for thin film deposition process (e.g. sputtering process), the anticontamination membrane comprising

a flexible sheet material for capturing scattered ions of the thin film deposition process;

wherein the flexible sheet material is operable to keep its integrity at the thin film deposition process.

The anticontamination membrane of claim 1 , wherein

the flexible sheet material comprises a layer of metal.

The anticontamination membrane of claim 1 or 2, wherein

the flexible sheet material comprises at least one ferromagnetic material.

The anticontamination membrane of any of the preceding claims, wherein the flexible sheet material comprises a substantially pure material, an oxide of the material or a combination of both.

The anticontamination membrane of any of the preceding claims, wherein the flexible sheet material further comprises a roughened surface.

The anticontamination membrane of claim 5, wherein

the roughened surface comprises an uneven surface.

The anticontamination membrane of any of the preceding claims, wherein the flexible sheet material has a thickness from 1 μιη to 1 mm substantially.

A thin film deposition equipment comprising:

a shield that comprises at least a portion of its surface covered by the anticontamination membrane of any of the preceding claims.

The thin film deposition equipment of claim 8 further comprising

> a holder for fastening a substrate for film growth; and

> at least one sputtering source for confining charged plasma particles;

> the shield comprises a vessel having a wall for enclosing the holder and the at least one sputtering source; and

at least one portion of the wall is covered by the anticontamination membrane of any of the preceding claims.

The thin film deposition equipment of claim 9, wherein

the at least one portion of the wall comprises a first inner surface covered by a first anticontamination membrane according to any of the preceding claims 1 to 7; and a second inner surface covered by a second anticontamination membrane according to any of the preceding claims 1 to 7.

A method for making an anticontamination membrane for thin film deposition process, the method comprising:

> providing a flexible sheet material for capturing scattered ions;

> exposing at least one portion of the flexible sheet material;

> roughening of a surface of the at least one portion the flexible sheet material; and

> detaching the at least one portion from the flexible sheet material. The method of claim 10, wherein

the roughening of a surface of the at least one portion the flexible sheet material comprises treating the surface by an electrolytic process.

The method of claim 10 or 1 1 , wherein

the roughening of the surface of the at least one portion the flexible sheet material comprises creating surface structure of the surface of the at least one portion the flexible sheet material.

The method of any of the preceding claims 10 to 12 further comprising oxidising the surface of the at least one portion the flexible sheet material.

14. The method of any of the preceding claims 10 to 13 further comprising attaching a base sheet to the flexible sheet material.

15. A method of using anticontamination membrane for thin film deposition process, the method comprising

> offering an anticontamination membrane according to any of the preceding claims 1 to 7;

> providing a thin film deposition equipment;

> attaching the anticontamination membrane to a wall of the thin film deposition equipment.

16. The method of claim 15 further comprising

performing thin film deposition process.

17. The method of claim 15 or 16 furthering

removing the anticontamination membrane from the wall.

18. The method of claim 15 or 16 furthering

treating the wall for a thin film deposition process.

19. The method of any of the preceding claims 15 to 18 furthering

recycling the anticontamination membrane.

20. The method of any of the preceding claims 15 to 19 furthering

making available a base sheet for the anticontamination membrane.