Abstract: The present disclosure relates to the field of manufacturing of silicon carbide (SiC) single crystal wafers, and discloses a stripping method and a stripping device for SiC single crystal wafers. The single crystal wafers obtained by the present disclosure have no damage layer or stress residue on surfaces or sub-surfaces, and are simple in operation and low in cost.

Abstract: The disclosure provides a silicon carbide seed crystal and a method of manufacturing a silicon carbide ingot. The silicon carbide seed crystal has a silicon surface and a carbon surface opposite to the silicon surface. A difference D between a basal plane dislocation density BPD1 of the silicon surface and a basal plane dislocation density BPD2 of the carbon surface satisfies the following formula (1), a local thickness variation (LTV) of the silicon carbide seed crystal is 2.5 ?m or less, and a stacking fault (SF) density of the silicon carbide seed crystal is 10 EA/cm2 or less: D=(BPD1?BPD2)/BPD1?25%??(1).

Abstract: Printheads for a jetting apparatus. In one embodiment, a printhead comprises a plurality of flow-through jetting channels each configured to jet a print fluid out of a nozzle. The printhead further includes a supply manifold fluidly coupled to the flow-through jetting channels, a return manifold fluidly coupled to the flow-through jetting channels, and one or more bypass manifolds fluidly coupled between the supply manifold and the return manifold.

Abstract: An electrolyte for electrochemical machining of a ?-?? nickel-based superalloy includes NaNO3 at a content of between 10 and 50% by weight relative to the total weight of the electrolyte; an additive chosen from KBr, NaBr, KI, NaI and mixtures thereof, in an additive/NaNO3 molar ratio of between 1 and 15; optionally an ethylenediaminetetraacetic acid-based complexing agent at a content of between 1 and 5% by weight relative to the total weight of the electrolyte at a pH of between 6 and 12; optionally an anionic surfactant at a content of between 1 and 5% by weight relative to the total weight of the electrolyte; optionally NaOH to obtain the appropriate pH; and an aqueous solvent.

Abstract: The invention relates to a weld cleaning fluid, and method of cleaning weld or discolouration especially on stainless steel. Stainless steel welds, such as those done by TIG welding, require cleaning to remove the resulting surface discolouration and also to passivate the steel. This is often done using an electro-cleaning apparatus with the assistance of electrolyte cleaning fluids. A new cleaning fluid has been developed that has a generally neutral pH, instead of the highly acidic nature of previously used fluids, which avoids environmental and safety issues. The cleaning fluid composition preferably has potassium or sodium orthophosphate salts as the main active ingredient, or similar such salts, and has a pH of around 7. It may also include a sequestering or chelating agent such as a sodium and/or potassium salt of EDTA, and colouring and fragrance.

Abstract: A method for surface treatment of a stainless steel separator for a fuel cell comprises preparing a stainless steel sheet containing nickel, chrome and iron, and having a passive film on a surface of the stainless steel sheet, and dipping the stainless steel sheet into a mixed etching solution of nitric acid (HNO3) and sulfuric acid (H2SO4) at a temperature of 50-70° C. for 30 seconds to 30 minutes to selectively lower an amount of Fe in the passive film formed on the surface of the stainless steel sheet.

Abstract: An aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 982 g/L and an effective concentration of ammonium bifluoride (ABF), and being substantially free of a strong acid. Methods of treating the surface of a non-ferrous metal workpiece include exposing the surface to a bath of an aqueous electrolyte solution including a concentration of citric acid less than or equal to about 300 g/L and a concentration of ammonium bifluoride greater than or equal to about 10 g/L, and having no more than about 3.35 g/L of a strong acid, controlling the temperature of the bath to be greater than or equal to about 54° C., connecting the workpiece to the anode of a DC power supply and immersing a cathode of the DC power supply in the bath, and applying a current across the bath.

Abstract: A system used in polishing the metal includes a base assembly and an electrolytic cell assembly. The base assembly has a support stand which is mounted on to a connecting element. The base assembly further includes a holding cylinder that is provided with a hook or similar kind of means that is adapted to hold an anode fixture. A process of polishing the metal using system includes providing stripping solution which is free of cyanide is taken in a glass beaker of the electrolytic cell assembly and is heated. Further, the products that are to be polished are mounted on to the anode fixture using the plurality of hooks.

Abstract: An apparatus, a method, and an electrolytic solution are described for electropolishing metallic stents made, for example, of high-strength medical alloys. The apparatus may include an electropolishing container made from material of low thermal conductivity. The apparatus may include at least one spiral cathode for optimization of solution agitation and/or voltage distribution in the electrolytic solution. Further, an electrolytic solution including at least dimethylsulfate is described. A method for improved electropolishing to consistently produce smooth surfaces is also described.

Abstract: Substantially anhydrous electropolishing electrolyte solutions. The substantially anhydrous electropolishing electrolyte solutions described herein do not use water as a solvent; instead, such electropolishing electrolyte solutions use anhydrous alcohols and/or glycols as a solvent. For example, an electropolishing electrolyte solution, as described herein, may include an alcohol, at least one mineral acid, and at least one water sequestering agent. Suitable examples of water sequestering agent include, but are not limited to, polyfunctional alcohols. Methods of electropolishing metal articles using such electropolishing electrolyte solutions are disclosed herein as well.

Abstract: An aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 982 g/L and an effective concentration of ammonium bifluoride (ABF), and being substantially free of a strong acid. Methods of treating the surface of a non-ferrous metal workpiece include exposing the surface to a bath of an aqueous electrolyte solution including a concentration of citric acid less than or equal to about 300 g/L and a concentration of ammonium bifluoride greater than or equal to about 10 g/L, and having no more than about 3.35 g/L of a strong acid, controlling the temperature of the bath to be greater than or equal to about 54° C., connecting the workpiece to the anode of a DC power supply and immersing a cathode of the DC power supply in the bath, and applying a current across the bath.

Abstract: A copper foil for a printed wiring board, the copper foil being characterized by having, on at least one surface thereof, a roughed layer of the copper foil in which an average diameter at a particle root (D1) corresponding to a distance of 10% of a particle length from the root, is 0.2 ?m to 1.0 ?m, and a ratio of the particle length (L1) to the average diameter at the particle root (D1) is 15 or less when L1/D1. A copper foil for a printed wiring board, wherein a sum of area covered by holes on an uneven and roughened surface of a resin is 20% or more at a surface of the resin formed by laminating the resin and a copper foil for a printed wiring having a roughened layer and then removing the copper layer by etching. An object of the present invention is to develop a copper foil for a semiconductor package board in which the aforementioned phenomenon of circuit erosion is avoided without deteriorating other properties of the copper foil.

Abstract: There is provided a mixture having a freezing point of up to 50° C., formed by reaction between: (A) one molar equivalent of a salt of formula I (Mn+)(X?)n I or a hydrate thereof; and (B) from one to eight molar equivalents of a complexing agent comprising one or more uncharged organic compounds, each of which compounds has (i) a hydrogen atom that is capable of forming a hydrogen bond with the anion X?; and (ii) a heteroatom selected from the group consisting of O, S, N and P that is capable of forming a coordinative bond with the metal ion Mn+, which reaction is performed in the absence of extraneous solvent, wherein M, X? mind a have meaning given in the description.

Abstract: Methods and apparatuses of stents with likely reduced rates of tissue perforation are provided. Some embodiments include reducing the profile of a portion of the stent using a wire profile reduction electropolishing bath and/or other wire profile reduction means.

Abstract: A substantially anhydrous electropolishing electrolyte solution that includes at least one sulfate salt. The substantially anhydrous electropolishing electrolyte solutions described herein do not use water as a solvent; instead, such electropolishing electrolyte solutions use anhydrous alcohols and/or glycols as a solvent. For example, an electropolishing electrolyte solution, as described herein, may include an alcohol, at least one mineral acid, and at least one sulfate salt. The at least one sulfate salt can act as a source of sulfate ions to replenish sulfate ions consumed in the electropolishing process. Anhydrous sulfate salts can also act as water scavengers by reacting with water to form sulfate salt hydrates. Methods of electropolishing metal articles using such electropolishing electrolyte solutions are disclosed herein as well.

Abstract: Substantially anhydrous electropolishing electrolyte solutions. The substantially anhydrous electropolishing electrolyte solutions described herein do not use water as a solvent; instead, such electropolishing electrolyte solutions use anhydrous alcohols and/or glycols as a solvent. For example, an electropolishing electrolyte solution, as described herein, may include an alcohol, at least one mineral acid, and at least one water sequestering agent. Suitable examples of water sequestering agent include, but are not limited to, polyfunctional alcohols. Methods of electropolishing metal articles using such electropolishing electrolyte solutions are disclosed herein as well.

Abstract: A method for etching a selected area of a conductive metal oxide layer deposited on a support is provided. The method comprises removing the area via electrochemical route in the presence of a polarized microelectrode and an electrochemical solution. In addition, an etched layer obtained with the foregoing method is provided.

Abstract: An aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 982 g/L and an effective concentration of ammonium bifluoride (ABF), and being substantially free of a strong acid. Methods of micropolishing a surface of a non-ferrous metal workpiece including exposing the surface to a bath of an aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 780 g/L and a concentration of ammonium bifluoride in the range of about 2 g/L to about 120 g/L and having no more than about 3.35 g/L of a strong acid, controlling the temperature of the bath to be between the freezing point and the boiling point of the solution, connecting the workpiece to an anodic electrode of a DC power supply and immersing a cathodic electrode of the DC power supply in the bath, and applying a current across the bath.

Abstract: This invention relates to methods of generating NP gallium nitride (GaN) across large areas (>1 cm2) with controlled pore diameters, pore density, and porosity. Also disclosed are methods of generating novel optoelectronic devices based on porous GaN. Additionally a layer transfer scheme to separate and create free-standing crystalline GaN thin layers is disclosed that enables a new device manufacturing paradigm involving substrate recycling. Other disclosed embodiments of this invention relate to fabrication of GaN based nanocrystals and the use of NP GaN electrodes for electrolysis, water splitting, or photosynthetic process applications.

Abstract: Bare aluminum baffles are adapted for resist stripping chambers and include an outer aluminum oxide layer, which can be a native aluminum oxide layer or a layer formed by chemically treating a new or used bare aluminum baffle to form a thin outer aluminum oxide layer.

Abstract: An aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 982 g/L and an effective concentration of ammonium bifluoride (ABF), and being substantially free of a strong acid. Methods of micropolishing a surface of a non-ferrous metal workpiece including exposing the surface to a bath of an aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 780 g/L and a concentration of ammonium bifluoride in the range of about 2 g/L to about 120 g/L and having no more than about 3.35 g/L of a strong acid, controlling the temperature of the bath to be between the freezing point and the boiling point of the solution, connecting the workpiece to an anodic electrode of a DC power supply and immersing a cathodic electrode of the DC power supply in the bath, and applying a current across the bath.

Abstract: An aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 982 g/L and an effective concentration of ammonium bifluoride (ABF), and being substantially free of a strong acid. Methods of treating the surface of a non-ferrous metal workpiece include exposing the surface to a bath of an aqueous electrolyte solution including a concentration of citric acid less than or equal to about 300 g/L and a concentration of ammonium bifluoride greater than or equal to about 10 g/L, and having no more than about 3.35 g/L of a strong acid, controlling the temperature of the bath to be greater than or equal to about 54° C., connecting the workpiece to the anode of a DC power supply and immersing a cathode of the DC power supply in the bath, and applying a current across the bath.

Abstract: An aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 982 g/L and an effective concentration of ammonium bifluoride (ABF), and being substantially free of a strong acid. Methods of treating the surface of a non-ferrous metal workpiece include exposing the surface to a bath of an aqueous electrolyte solution including a concentration of citric acid less than or equal to about 300 g/L and a concentration of ammonium bifluoride greater than or equal to about 10 g/L, and having no more than about 3.35 g/L of a strong acid, controlling the temperature of the bath to be greater than or equal to about 54° C., connecting the workpiece to the anode of a DC power supply and immersing a cathode of the DC power supply in the bath, and applying a current across the bath.

Abstract: Anode foil, preferably aluminum anode foil, is etched using a process of treating the foil in an electrolyte bath composition comprising a sulfate and a halide, such as sodium chloride. The anode foil is etched in the electrolyte bath composition by passing a charge through the bath. The etched anode foil is suitable for use in an electrolytic capacitor.

Abstract: A solution system for removing titanium carbide coatings on substrate surface by two electrolysis steps is provided. The solution system includes a first electrolyte solution for a first electrolysis step and a second electrolyte solution for a second electrolysis step. The first electrolyte solution contains 2-80 g/L soluble alkali metal hydroxide and 5-100 g/L complexant capable of complexing with titanium ions. The second electrolyte solution contains 50-300 g/L soluble alkali metal hydroxide, 5-100 g/L complexant capable of complexing with titanium ions, and 10-60 g/L alkylol amine. The method for removing titanium carbide coating from the substrate mainly includes two electrolysis steps respectively using the first and second electrolyte solution.

Abstract: A porous titanium dioxide film having photonic properties is made by etching a titanium substrate in an electrolyte solution in the presence of an electric field. The electrolyte solution can be an organic electrolyte solution. Etching involves providing an electrolyte solution in contact with a pair of electrodes and passing an electric current through the electrolyte solution. The titanium substrate can be one of the pair of electrodes. The current has a wave profile selected from a group consisting of a periodic square profile, a sine wave, a linear profile, or a quintic profile, and is provided either parallel of perpendicular to a plane of the substrate.

Abstract: Anode foil, preferably aluminum anode foil, is etched using a process of treating the foil in an electrolyte bath composition comprising a sulfate and a halide, such as sodium chloride. The anode foil is etched in the electrolyte bath composition by passing a charge through the bath. The etched anode foil is suitable for use in an electrolytic capacitor.

Abstract: An aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 982 g/L and an effective concentration of ammonium bifluoride (ABF), and being substantially free of a strong acid. Methods of micropolishing a surface of a non-ferrous metal workpiece including exposing the surface to a bath of an aqueous electrolyte solution including a concentration of citric acid in the range of about 1.6 g/L to about 780 g/L and a concentration of ammonium bifluoride in the range of about 2 g/L to about 120 g/L and having no more than about 3.35 g/L of a strong acid, controlling the temperature of the bath to be between the freezing point and the boiling point of the solution, connecting the workpiece to an anodic electrode of a DC power supply and immersing a cathodic electrode of the DC power supply in the bath, and applying a current across the bath.

Abstract: An apparatus, a method, and an electrolytic solution are described for electropolishing metallic stents made, for example, of high-strength medical alloys. The apparatus may include an electropolishing container made from material of low thermal conductivity. The apparatus may include at least one spiral cathode for optimization of solution agitation and/or voltage distribution in the electrolytic solution. Further, an electrolytic solution including at least dimethylsulfate is described. A method for improved electropolishing to consistently produce smooth surfaces is also described.

Abstract: The present invention relates to a method for removing metal oxides from a substrate surface. In one particular embodiment, the method comprises: providing a substrate, a first, and a second electrode that reside within a target area; passing a gas mixture comprising a reducing gas through the target area; supplying an amount of energy to the first and/or the second electrode to generate electrons within the target area wherein at least a portion of the electrons attach to a portion of the reducing gas and form a negatively charged reducing gas; and contacting the substrate with the negatively charged reducing gas to reduce the metal oxides on the surface of the substrate.

Abstract: The present invention pertains to the use of an additive selected from the group consisting of amorphous silica, graphite powder, and a mixture thereof in a process to electroplate or electropolish a metal on a substrate using an ionic liquid as the electrolyte to increase metal layer thickness. It furthermore pertains to a method to electroplate or electropolish a metal on a metal substrate wherein an ionic liquid is employed as electrolyte, wherein a metal salt added to said ionic liquid or a metal anode is employed as metal source, and wherein said ionic liquid comprises said additive.

Abstract: A composition for use in polishing a wafer is disclosed. The composition includes an aqueous solution of initial components substantially free of loose abrasive particles and having a pH in the range of about 2 to 7, the aqueous solution including at least one polyelectrolyte and a surfactant. In certain embodiments, the wafer polishing composition can be adjusted to control cut rate and selectivity for modifying semiconductor wafers using a fixed abrasive Chemical Mechanical Polishing (CMP) process. Also disclosed is a CMP method and a process for polishing a wafer using the polishing composition.

Abstract: The invention relates to the defoaming of ionic liquids and also to compositions comprising at least one ionic liquid and at least one antifoam and, if appropriate, a solvent and/or further auxiliaries or additives.

Abstract: The present invention relates to a method to electroplate or electropolish a metal on a substrate wherein an ionic liquid selected from the group of N+R1R2R3R4X? or N+R5R6R7R8Y? is employed as electrolyte, and a metal salt added to the ionic liquid is employed as the metal source or a metal anode is used as the metal source, wherein any one of R1 to R8 independently represents a hydrogen, alkyl, cycloalkyl, aryl, or aralkyl group that may be substituted with a group selected from OH, Cl, Br, F, I, phenyl, NH2, CN, NO2, COOR9, CHO, COR9, or OR9, at least one of R5 to R8 is a fatty alkyl chain, and one or more of R5 to R8 can be a (poly)oxyalkylene group wherein the alkylene is a C1 to C4 alkylene and the total number of oxyalkylene units can be from 1 to 50 oxyalkylene units, and at least one of R1 to R8 is a C1 to C4 alkyl chain, R9 is an alkyl or cycloalkyl group, X- is an anion having an N-acyl sulphonylimide anion (—CO—N?—SO2—) functionality, Y? is an anion compatible with the N+R5R6R7R8 ammonium cation, s

Abstract: The present invention relates to a method for removing metal oxides from a substrate surface. In one particular embodiment, the method comprises: providing a substrate, a first, and a second electrode that reside within a target area; passing a gas mixture comprising a reducing gas through the target area; supplying an amount of energy to the first and/or the second electrode to generate electrons within the target area wherein at least a portion of the electrons attach to a portion of the reducing gas and form a negatively charged reducing gas; and contacting the substrate with the negatively charged reducing gas to reduce the metal oxides on the surface of the substrate.

Abstract: There is provided a mixture having a freezing point of up to 50° C., formed by reaction between: (A) one molar equivalent of a salt of formula I (Mn+)(X?)n I or a hydrate thereof; and (B) from one to eight molar equivalents of a complexing agent comprising one or more uncharged organic compounds, each of which compounds has (i) a hydrogen atom that is capable of forming a hydrogen bond with the anion X?; and (ii) a heteroatom selected from the group consisting of O, S, N and P that is capable of forming a coordinative bond with the metal ion Mn+, which reaction is performed in the absence of extraneous solvent, wherein M, X? mind a have meaning given in the description.

Abstract: Methods for etching nickel and nickel alloy layers are disclosed. The etching compositions include inorganic acids and heterocyclic nitrogen compounds. Additionally, the etching methods may include anodic etching of the nickel or nickel alloy layer. The methods may be used in semiconductor packaging manufacture.

Abstract: Disclosed is an electrolyte for electrochemical machining of a metal product, which can reduce a defect of an electro-chemical machining product, increase a lifespan of an electrolyte and an electrode, and improve efficiency of the electrochemical machining. The electrolyte includes an inorganic salt and at least one of a complexing agent and a reducing agent in a solvent.

Abstract: Methods and compositions have been provided for removing barrier layer material from a work piece during an electrochemical mechanical polishing process while protecting a metallization layer of the work piece. The electrochemical planarization composition includes at least one complexing agent capable of complexing with the barrier layer material when exposed to a pH outside of a pH range of greater than about pH 2 and less than about pH 10, a corrosion inhibitor, abrasive particles, and a pH adjuster.

Abstract: Electrolyte compositions and methods for planarizing a surface of a substrate using the electrolyte compositions are provided. In one aspect, an electrolyte composition includes one or more chelating agents, one or more corrosion inhibitors, and one or more pH adjusting agents. In another aspect, an electrolyte composition includes one or more chelating agents, two or more corrosion inhibitors, and one or more pH adjusting agents. In another aspect, an electrolyte composition includes one or more chelating agents, one or more corrosion inhibitors, one or more pH adjusting agents, and one or more electrically resistive additives.

Abstract: The present invention relates to a method for the electropolishing of surfaces of metals and metal alloys. Said method is characterized in particular in that it can be applied to a wide range of metals. Thus, it is suitable for the electropolishing of metal surfaces comprising iron, tungsten, magnesium, aluminum or an alloy of these metals. The electrolyte used in the method comprises methanesulfonic acid and at least one alcoholic compound selected from aliphatic diols of general formula CnH2n(OH)2 with n=2-6 and alicyclic alcohols of general formula CmH2m-1OH with m=5-8.

Abstract: The invention is directed to an electropolishing solution for products or devices made from at least in part a cobalt-chromium alloy. The invention is particularly suitable for medical devices or intravascular stents made at least in part of cobalt-chromium. More particularly, the electropolishing process of the invention is particularly suited for use on implantable medical devices, such as stents, due to the biocompatibility of cobalt-chromium alloys. The invention is directed to an improved stent formed from a cobalt-chromium alloy, that possesses an ultrasmooth shiny surface. This invention is also directed to a method of electropolishing such a stent using an acidic electrolytic solution comprising a mixture of 6 parts of about 98% sulfuric acid (H2SO4), 1 part of about 37% hydrochloric acid (HCl) and 1 part by of about 85% concentrated phosphoric acid (H3PO4) to produce an exceptionally smooth surface.

Abstract: Deionisation and clarification process of the aqueous medium used in an electroerosion machine and product for this process, where the electroerosion machines are comprised of a purification circuit for this aqueous medium, which includes an ion exchange phase between some cationic and anionic resins with the aqueous dielectric medium, which has a conductivity of less than 40 ?S/cm, and to which a solution of oxalic acid and phosphoric acid in distilled/deionised water is added in the approximate proportion of oxalic acid between 0.18 and 0.035 moles and phosphoric acid between 1.28 and 2.5 moles per liter of solution.

Abstract: A method for making nanoparticles, nanoparticle inks and device layers therefrom is disclosed. In accordance with the present invention, nanoparticles are isolated from a composite material that is formed by treating a metal oxide precursor to form the metal nanoparticles and a metal oxide matrix. The nanoparticles are then isolated from the composite material by etching at least a portion of the metal oxide matrix to release the metal nanoparticles. In accordance with the embodiments of the invention, the nanoparticles are treated with surfactants and wetting agents either while etching or after etching, are isolated from the etchant and dispersed in a solvent medium and/or are otherwise treated or modified for use in a nanoparticle inks. A layer of the metal nanoparticle ink can then be used to form doped, undoped, patterned and unpatterned device layers or structures in micro-devices.

Abstract: An aqueous thiourea-free gold etching bath for electrolytically etching gold from a microelectronic workpiece. One embodiment of the aqueous thiourea-free bath contains: (a) about 0.5–1.5 M iodide; (b) about 0.1–0.3 M sulfite; and (c) about 1.0–3.0 g/L wetting agent. The bath is useful in a process for electrolytically etching gold from a microelectronic workpiece. A tool system in which the baths and processes of the present invention may be used is also described.

Abstract: An electropolishing method for removing potential device-contaminating particles from a wafer, is disclosed. The method includes immersing the wafer in an electropolishing electrolyte solution and removing defects and particles from the wafer by rotational friction between the wafer and the electrolyte solution in combination with electrolysis. The method is effective in removing particles from via openings of all sizes, including via openings having a width smaller than about 0.2 ?m.

Abstract: Polishing compositions and methods for removing conductive materials from a substrate surface are provided. In one aspect, a composition includes an acid based electrolyte system, one or more chelating agents, one or more corrosion inhibitors, one or more inorganic or organic acid salts, one or more pH adjusting agents to provide a pH between about 3 and about 10, a polishing enhancing material selected from the group of abrasive particles, one or more oxidizers, and combinations thereof, and a solvent. The composition may be used in an conductive material removal process including disposing a substrate having a conductive material layer formed thereon in a process apparatus comprising an electrode, providing the composition between the electrode and substrate, applying a bias between the electrode and the substrate, and removing conductive material from the conductive material layer.

Abstract: Process for the production of shaped articles of niobium or tantalum by electrochemical etching of a niobium or tantalum sheet covered by a structured photoresist mask in an aqueous solution containing hydrofluoric acid, the etching being effected under electrochemical conditions under which strong noise is superposed on the etching current and the etching solution contains a water-soluble polymer.

Abstract: A method of manufacture for optical spectral filters with omnidirectional properties in the visible, near IR, mid IR and/or far IR (infrared) spectral ranges is based on the formation of large arrays of coherently modulated waveguides by electrochemical etching of a semiconductor wafer to form a pore array. Further processing of said porous semiconductor wafer optimizes the filtering properties of such a material. The method of filter manufacturing is large scale compatible and economically favorable. The resulting exemplary non-limiting illustrative filters are stable, do not degrade over time, do not exhibit material delamination problems and offer superior transmittance for use as bandpass, band blocking and narrow-bandpass filters. Such filters are useful for a wide variety of applications including but not limited to spectroscopy, optical communications, astronomy and sensing.

Abstract: The present invention provides methods of polishing and/or cleaning copper interconnects using bis(perfluoroalkanesulfonyl) imide acids or copper tris(perfluoroalkanesulfonyl) methide acids compositions.