Abstract: In order to prevent salt precipitation after plating a wafer surface, the described cleaning process applied to the wafer covered with a plating solution uses a complex former solution or the solution of an acid. The presence of a suitable complex former enhances the solubility of heavy metal ions typically by orders of magnitudes. Hereby a precipitation of salts is avoided. After plating, the wafer is necessarily covered with a plating solution. In a first cleaning step, the solution of the complex former is applied on the wafer surface. This procedure reduces the amounts of plating salts in the solution and keeps the solubility of the remaining salts high at the same time due to a formation of soluble metal complexes. After that step, the wafer is completely covered with clean complex solution. This solution is removed in a following step by a stream of de-ionized water, leading to a clean, water-covered wafer. The drying of the wafer can be performed in a conventional procedure (e.g.

Abstract: A substrate is plated with a metal film of uniform thickness only in a limited area thereof which is to be plated. A substrate plating apparatus has a substrate holder for holding a substrate and a plating cell for plating a portion of a surface, to be plated, of the substrate held by the substrate holder. The plating cell has an anode disposed so as to cover the portion of the surface, to be plated, of the substrate held by the substrate holder, a cathode for supplying a current to the surface, to be plated, of the substrate in such a state that the cathode is brought into contact with the substrate, a plating liquid supplying device for supplying a plating liquid between the anode and the surface, to be plated, of the substrate, and a power source for applying a voltage between the anode and the cathode.

Abstract: A method of reducing etching of a seed layer by a plating solution. Prior to introducing the semiconductor wafer with the seed layer into the plating solution, the etching power of the plating solution is diminished.

Abstract: A method and an apparatus are described for regulating the concentration of metal ions in an electrolytic fluid, which is used for the deposition of metal with insoluble anodes and additionally contains compounds of an electrochemically reversible redox system. With the oxidized form of said system, metal is dissolved in an ion generator 1, traversed by the fluid, so that these compounds are thereby reduced. For the deposition of metal, the dissolved metal ions on the item to be treated are reduced. The compounds of the redox system in the reduced form are oxidized again on the insoluble anodes in the electroplating system 13. In order to keep the concentration of the metal ions in the electrolytic fluid constant, at least a portion of the electrolytic fluid, contained in the electroplating system, is conducted through one or a plurality of electrolytic auxiliary cells 6.

Abstract: An array of selectively addressible microelectrodes for combinatorial synthesis of complex polymers or alloys.

Abstract: A process for galvanic depositing of a dispersion layer on a surface of a work piece, in particular a contact layer on a plain bearing half liner, is described, whereby an electrolyte with the dispersed phase finely distributed therein is moved opposite the work piece surface to be coated with formation of a flow component parallel to the surface. In order to create advantageous processing conditions it is proposed that the surface of the work piece to be coated is profiled prior to coating with an average minimum profile depth of 5 &mgr;m and is then coated transversely to a relevant profile direction in a flow component of the electrolyte opposite the work piece surface.

Abstract: A method of reducing etching of a seed layer by a plating solution. Prior to introducing the semiconductor wafer with the seed layer into the plating solution, the etching power of the plating solution is diminished.

Abstract: A process and apparatus for supplying a soluble metal compound to an electrolyte solution uses a powder wetting device in a loop from a working tank. The powder wetting machine supplies the powdered metal compound directly into the electrolyte solution which rapidly dissolves to replenish the electrolyte compound during the treating process. The process and apparatus are particularly suitable for replenishing the metal salts consumed during an electroplating process.

Abstract: A metal plating apparatus is described which includes a compressible member having a conductive surface covering substantially all of the surface of the substrate to be plated. The plating current is thereby transmitted over a wide area of the substrate, rather than a few localized contact points. The compressible member is porous so as to absorb the plating solution and transmit the plating solution to the substrate. The wafer and compressible member may rotate with respect to each other. The compressible member may be at cathode potential or may be a passive circuit element.

Abstract: A process for electrochemical oxidation of aldehydes to esters is provided. The invention includes electrooxidation at a pH where an intermediate hemiacetal is favored, thereby providing for maximum selectivity to the desired ester and for maximum reaction efficiency. In particular, the invention provides for the electrooxidation of acetaldehyde to methyl acetate. The invention is illustrated with reference reactants native to the carbonylation process for the manufacture of acetic acid. Processes described herein are readily adapted to an industrial scale, particularly for the removal of acetaldehyde from process streams.

Abstract: Process and apparatus controlling the cross-sectional flow distribution within a flowing stream such as a copper flux in an electrolytic copper deposition process. The flow distribution is controlled by a baffle comprised of two plates overlying one another, each having a set of openings, wherein the openings in the two plates generally correspond to one another but are slightly offset therefrom or varied in size in a non-uniform way along the radius of the plates such as to effect a modification of the uniformity or non-uniformity of the velocity flow rates across the cross section of the flowing stream in which the baffle is interposed.

Abstract: A method for producing a circuit substrate having a bump contact point, comprising the steps of (a) disposing a positive electrode in a plating solution stored in a storage tank, (b) exposing a conductive circuit formed on an insulating substrate, above the surface of the plating solution, (c) disposing a jet stream opening below the surface of the plating solution, and (d) spouting out the plating solution from the jet stream opening toward the negative electrode for electroplating using said conductive circuit as a negative electrode, to form the bump contact point on the surface of the negative electrode, and a jet stream type plating apparatus used therefor. According to the present invention, mixing of air bubbles in the plating solution can be inhibited, which in turn enables suppression of oxidative decomposition of the brightener components. As a consequence, the bump contact point can have a mushroom shape, and variation in the height of the bump contact points can be minimized.

Abstract: A rotary plater and method of plating are provided which improve the uniformity of plating across a plating surface of a workpiece. A plating solution distribution device is located in a plating cup between an anode and a cathode in a spaced relationship therebetween and is centered about a vertical axis of the plating cup. A motor is provided for relatively rotating the cathode and the plating solution distribution device with respect to one another. The plating solution distribution device distributes the plating solution over the plating surface at a distribution rate which increases radially outwardly from the vertical axis. With this arrangement the volume of plating solution at the outer periphery of the plating surface is enriched with ions to promote plating uniformity.

Abstract: The invention relates to a process for electrolytic treatment of copper foil, comprising the steps of: (A) applying a voltage across an anode and cathode, wherein the anode and cathode are in contact with an electroplating composition containing a gelatin component; (B) removing organic particulate matter by contacting the electroplating solution containing the organic particulate matter with an adsorbent polymer; and (C) electrolytically treating the copper foil. The electroplating composition can additionally contain an active sulfur-containing component, such as thiourea.

Abstract: An electrolytic cell comprising bipolar electrodes is employed for electrochemical deposition of copper, zinc, lead, nickel or cobalt. An interior space is provided between the cathode side and the anode side of a bipolar electrode. The electrolyte can flow substantially without an obstruction through the interelectrode space between adjacent electrodes. The current densities in the interelectrode space amount to 800 to 8000 A/m.sup.2. Gas is evolved on the anode side of the bipolar electrodes and causes liquid to flow along the anode side. In the middle of the height of the anode side that liquid flow has a vertical component having a velocity of 5 to 100 cm/second. Electrolyte solution flows from the upper edge portion of the anode side to a return flow space, in which the solution flows downwardly. From the return flow space the solution is returned to the lower portion of the interelectrode space.

Abstract: The present invention is a method of forming a phosphate chemical treatment film which is efficient and allows a high-quality chemical film to be obtained, by which a substance to be treated is subjected to electrolytic treatment while removing the sludge, which consists of impurities other than the unavoidable impurities in the phosphate chemical treatment bath. According to this method, an adequate phosphate chemical treatment film may be formed onto any type of metal material, to provide phosphate chemical treatment films having thicknesses not obtainable by the prior art.

Abstract: The invention describes a process for the electrolytical coating of an object of steel on one or both sides. Preferably, the object is a steel strip with zinc or a zinc iron alloy. Zinc or a zinc iron alloy is deposited on the object when the object is connected to form the cathode of a galvanic cell in an aqueous solution of zinc chloride and iron chloride with a pH of 0.1 to 3.0. The zinc chloride solution has a concentration of 50 to 1000 g/l for the deposition of metallic zinc. A partial flow of electrolyte solution is past continuously into a column filled with metallic zinc, where the trivalent iron formed there during the electrolysis is reduced to a bivalent iron, and metallic zinc is dissolved simultaneously therewith. The invention also describes an apparatus for the electrolytical coating of an object of steel.

Abstract: A process for electroplating a substrate by coating the substrate with a coating of conductive particles. The coating of conductive particles is applied to the substrate from an unstable aqueous dispersion essentially free of a dispersing agent using physical dispersion means to maintain the stability of the dispersion.

Abstract: An apparatus for continuously dissolving metal powder for use in plating includes a dissolving tank for dissolving metal powder for used in plating solution in a solvent, a filter for separating the solution containing undissolved residue into an undissolved residue and a filtrate, a recovery tank of the filtrate, and a plating solution storing tank for supplying recovered filtrate to a plating tank. The filter is a porous substance having a plurality of liquid passages in the axial direction thereof, and the filter is provided with a circuit for returning a liquid solution containing the undissolved residue passed through the passages to the dissolving tank and a pipeline for leading the filtrate to the recovery tank.A method of dissolving a nickel metal, which has a specific surface of 0.003 m.sup.2 /g or more, is dissolved with the use of the above-described apparatus.

Abstract: A first pair electrodes consisting of an anode to which a plurality of wiring lines to be anodized are connected and a cathode that is opposed to the anode, and a second pair electrodes for collecting impurities in a forming solution are immersed in a forming solution. A voltage is applied to the plurality of wiring lines in such a manner that at least one of the plurality of wiring lines receives the voltage for a different period than the other wiring lines.

Abstract: A method of recovering volatile ruthenium, which is separated and formed by constant potential electrolysis from high-level radioactive liquid waste discharged from the reprocessing step of spent nuclear fuel by purex process, in the form of stable solid. The method comprises electrolyzing at a constant potential a high-level radioactive liquid waste from which palladium has substantially been removed in advance, thereby vaporizing ruthenium, bringing the vaporized ruthenium into contact with an aqueous solution of formic acid to precipitate ruthenium oxide, and separating the precipitate from the aqueous solution of formic acid.

Abstract: An electroplated element is formed to include an insulating substrate, a conducting polymer polymerized in situ on the substrate, and a metal layer deposited on the conducting polymer. In one application a circuit board is formed by polymerizing pyrrole on an epoxy-fiberglass substrate in a single step process and then electrodepositing a metal over the resulting polypyrrole polymer. No chemical deposition of the metal is required prior to electroplating and the resulting layer of substrate-polymer-metal has excellent adhesion characteristics. The metal deposition is surprisingly smooth and uniform over the relatively high resistance film of polypyrrole. A continuous manufacturing process is obtained by filtering the solution between successive substrates to remove polymer formed in the solution, by maintaining the solution oxidizing potential within selected limits, and by adding a strong oxidant, such as KMnO.sub.

Abstract: An electrolytic cell system wherein an alkali metal chloride is electrolized to produce chlorine and alkali metal hydroxide in a diaphragm-type cell by feeding an aqueous slurry of an alkali metal chloride particulate to an anode compartment of the cell through at least one primary conduit and then a secondary conduit at a linear velocity of at least 6.5 feet per second. The secondary conduit has an interior cross-sectional area up to about 0.2 square inch and less than that of the primary conduit. By means of the described feed system, substantially uniform quantities of the aqueous slurry can be substantially simultaneously and continuously fed to a plurality of anode compartments.