Showing papers on "Electroplating published in 1977"

Method of manufacturing amorphous alloy

Abstract: A method of manufacturing an amorphous alloy in which there is provided an acidic plating bath consisting predominantly of divalent iron ions and a source of hypophosphite ions, and electroplating from such a bath to produce a plated layer of an amorphous alloy consisting predominantly of iron and phosphorous.

Method of making solar cell with multiple-metal contacts

Abstract: Solar cell having a contact formed from a titanium group element in contiguous relationship with the cell, a mixture of a titanium group element and a platinum group element overlying the titanium group layer, and a layer of a platinum group element overlying that layer. A body of silver or other contact metal is adhered to the platinum group layer. The three layers may be vapor deposited on the semiconductor body, while the silver layer is more advantageously applied by plating or electroplating.

Apparatus for electroplating sheet metals

Abstract: Metal in sheet or strip form is electroplated in a continuous or semi-continuous process in which a running length of the metal is passed through a bath of electrolyte solution having an anode structure supported therein adjacent the surface or surfaces to be electroplated. The structure of the anode enables use of the apparatus to electroplate strips of various widths without encountering adverse side effects or streaking and enables substantial economies in electrical current. The anode structure is particularly useful in the production of strip steel having a zinc coating on one side only.

Bright electroless plating process producing two-layer nickel coatings on dielectric substrates

Abstract: An adherent, bright metallic nickel coating is applied to the surface of a plastic or other dielectric part (or to a metal part) by an electroless process comprising, after suitable pretreatment of said surface, the deposition of a primary electroless nickel possessing special properties followed by a secondary electroless nickel of bright appearance with complete elimination of any subsequent electroplating process usually required to achieve this brightness. The nickel coating may be limited to selected surface areas of a coated part by mechanically removing portions of the primary coat prior to immersion of the part in a secondary electroless nickel bath.

Method of making a metalized substrate having a thin film barrier layer

Abstract: A method of fabricating a hybrid circuit including a siliceous substrate and thick metal conductors. A thin film barrier layer is provided intermediate the substrate and a vacuum-deposited metal layer, which metal layer is subsequently electroplated to provide the desired metal thickness. The barrier layer, which may suitably be a refractory metal oxide such as the oxides of zirconium, tantalum, titanium, or tungsten, prevents loss of adhesion between the vacuum deposited metal and substrate that occurs during electroplating.

Continuous electroplating apparatus

Abstract: Apparatus useful for the continuous manufacture of metal foil or printed circuit patterns includes a cathode supported over a plating tank with its flat bottom surface disposed horizontally. A continuous strip of basis metal to be plated is fed horizontally over the tank from reel to reel while being held in sliding contact with the bottom surface of the cathode by suction. Within the plating tank a pair of insoluble anodes having a block of electrically insulating material sandwiched therebetween are mounted opposite to the cathode, with a spacing between each anode and the basis metal traveling under the cathode. The insulating block has an upwardly opening groove formed transversely therein, and from this groove the electrolyte solution within the tank is caused to flow turbulently through the spaces between the anodes and the basis metal traveling under the cathode in order to speed the electrodeposition, as of copper, on the downward-facing surface of the basis metal.

Method and means for electrolytic precleaning of substrates and the electrodeposition of aluminum on said substrates

Abstract: Adherent deposits of aluminum can be obtained on metallic substrates by anodic etching of the substrates (reverse current electrolytic cleaning) employing a novel etch solution made as follows: 1. reacting a sufficient amount of aluminum with a hydrogen halide such as HCl, HBr, or HI (preferably hydrogen bromide) in an organic solvent such as benzene or toluene (and in the absence of water) to form a solution in which the concentration of the dissolved aluminum is from 2.0 M to 3.5 M; and 2. then adding hydrogen halide to the resulting solution of 1) above such that the hydrogen ion concentration of the said resulting solution is greater than 1.0 M but below the saturation point of hydrogen halide in said solution. Prior to the actual plating operation, the novel etch solution just described is directed to a plating chamber wherein the metallic substrate is electrocleaned by reverse current anodic etching, i.e., the substrate becomes the anodic terminal of the cell, the reverse of its electric potential in normal electroplating. Then the electroplating electrolyte is directed to the plating chamber to flush out the etch solution. Finally, fresh electroplating electrolyte is directed to the plating chamber for electroplating of the substrate, which is now rendered cathodic.

Acid zinc electroplating process and composition

Abstract: This invention relates to a method of producing bright zinc electrodeposits over a wide current density range, which comprises passing current from a zinc anode to a metal cathode for a time period sufficient to deposit a bright zinc electrodeposit upon said cathode; the current passing through an aqueous acidic bath composition containing at least one zinc compound providing zinc cations for electroplating zinc such as zinc chloride, zinc fluoborate, zinc sulfamate and zinc sulfate; chloride, fluoborate, sulfamate and/or sulfate anions may be added as salts of bath compatible cations to provide better electrical conductivity, and containing as cooperating additives at least one bath soluble substituted or unsubstituted polyether, at least one aliphatic unsaturated acid containing an aromatic or heteroaromatic group and at least one aromatic or N-heteroaromatic aldehyde.

Composite electrodeposits and alloys

Abstract: An alloy difficult to produce by conventional electrodeposition techniques is produced by electrodepositing at least one metal selected from the group comprising nickel, up to 50% cobalt, and iron with particles incorporating metal in chemically combined state. The particles contain a reactive element, such as carbon, nitrogen, and boron, and a metallic element, such as chromium, molybdenum, and tungsten. The electrodeposit of the particles in a metal matrix is treated in a reducing atmosphere so that the particles react, releasing at least some of their incorporated metal into the matrix to form the alloy while transferring the reactive element to the reducing atmosphere. This invention relates to a process for the production of an alloy. It is known to codeposit two or more metals on a substrate by electrodeposition either as permanent coatings or as coatings subsequently removed from the substrate, such as electroforms, to form an alloy with or without diffusion heat treatment. However, electrodeposition is subject to electrochemical restrictions which at best limit the alloy composition depositable or make it necessary to use commercially unsatisfactory process conditions and which at worst prevent certain alloys being produced as electroforms or even being produced at all by electrodeposition. For example, while attempts have been made to produce a nickel-chromium alloy electrodeposit by codepositing nickel and chromium metal, it has not proved possible in this way to produce commercially satisfactory nickel-chromium alloy electrodeposits containing useful amounts of chromium in the nickel matrix. Indeed the deposition processes used in these attempts have suffered from defects which have tended to make the processes themselves unsuitable for commercial usage. It is an object of the present invention to provide a process of making an electrodeposit of an alloy which is normally difficult to produce by conventional electrodeposition techniques. Generally speaking, the present invention is a process for producing an alloy comprising: coelectrodepositing a matrix of at least one metal selected from the group consisting of nickel, less than 50% by weight cobalt, and iron, with reactive particles incorporating metal in chemically combined state, said particles are compounds of at least one reactive element selected from the group consisting of carbon, nitrogen, and boron, and of at least one metallic element selected from the group consisting of chromium, molybdenum, and tungsten, thereby providing a composite electrodeposit; and heating said composite electrodeposit to temperatures of from about 1000° C. to about 1400° C. for at least 24 hours in a reducing gas atmosphere to release at least some of said metallic element of said particles from its chemically combined state into said matrix thereby forming said alloy while transferring at least some of said reactive element to said reducing gas atmosphere. While the process of the invention primarily is intended for the production of alloys which are difficult or even impossible to produce by conventional electrodeposition techniques, it is of course equally applicable to the production of alloys which can readily be produced by conventional electrodeposition techniques. Furthermore, the process of the invention can be used for the formation of alloy permanent coatings on a substrate or for the formation of coatings which are subsequently removed from the substrate, such as electroforms. References throughout this specification to "coatings" are to be taken to include electroforms which have been removed from the substrate upon which they were formed. The thermally decomposable reactive particles incorporating metal in chemically combined state may be codeposited in conjunction with particles which do not react under the conditions used to make the reactive particles react. In this way, an alloy may be produced containing particles which constitute, for example, a dispersion hardening dispersoid. The reactive particles incorporating metal in chemically combined state may alternatively or additionally to the foregoing non-reactive particles be codeposited with metal particles and/or with coated metal particles, for example, carbide coated metal particles. Although it has been proposed in the past to electrodeposit coatings made up of particles, incorporating metal in chemically combined state, in a metal matrix to improve the hardness and/or wear resistance of the matrix metal, such proposals have only resulted in the production of a composite coating of particles incorporating metal in chemically combined state in a metal matrix and not an alloy. Alloy production, it is thought, was precluded by the use of: (a) unreactive particles incorporating metal in chemically combined state, or (b) the wrong metal or metals, or (c) the use of process conditions or relative proportions of particles incorporating metal in chemically combined state, and matrix metal, which prevented reaction of the particles. For example, chromium carbide (Cr 3 C 2 ) and cobalt have been codeposited to form a Co--Cr 3 C 2 composite coating with improved initial hardness values, but have not been used to form an alloy. Preferably the process of the invention is used to codeposit nickel or nickel and up to 50% cobalt with chromium carbide particles to form an electrodeposited nickel-chromium or nickel-cobalt-chromium coating. Advantageously, sufficient chromium carbide particles should be utilized to give at least 13% chromium in the electrodeposited coating. However, when the electrodeposited coating contains both cobalt and chromium carbide particles, less than 50% by weight of the matrix should be cobalt, since more than this amount of cobalt leads to excessively high internal stress which precludes the use of such electrodeposites. The particles incorporating metal in chemically combined state can be reacted by heating in a reducing atmosphere such as hydrogen for at least 24 hours at temperatures of from about 1000° C. to about 1400° C. The degree of reaction of the particles incorporating metal in chemically combined state may be controlled, for example, by variation of the heat treatment temperature and/or time to allow different desired amounts of metal incorporated in the particles to be released. In this way, different properties may be achieved in the electrodeposited coatings. An advantageous heat treatment is to heat in hydrogen at 1000° C. for 24 hours and air cool. It is preferred to transfer at least 50% of the reactive element from the electrodeposit to the reducing gas atmosphere. Deposits prepared according to the invention may be applied electrolytically, using any convenient electroplating solution such as a Watts bath or sulfamate solution which may be used for electroforming. Preferably an aqueous electroplating solution should be used, although a non-aqueous solution may be employed where suitable. Whether aqueous or non-aqueous, the solution used in the process according to the present invention may deteriorate with time, and it is recommended that such solutions be used while fresh and/or frequently discarded and replaced with fresh solutions. When an electroform is being prepared by the process according to the invention, the particles incorporating metal in chemically combined state should be reacted, for example, by heating, preferably after the electroform is stripped from the substrate upon which it was formed. Alloys made according to the invention may be harder or softer in the as-plated condition than an electrodeposited coating of the alloy matrix metal in the as-plated condition, depending upon the particular metal or metals being considered. However, no matter whether the alloy is harder or softer in the as-plated condition than an electrodeposited coating of the matrix metal alone in the as-plated condition, the alloy retains its hardness after or on heating, to a much greater extent than does the coating of the matrix metal alone. Furthermore, such hardness property improvements may be obtained with alloys made according to the invention, without unduly affecting the electroformability of the alloys.

Process for making a metal plastic structure

Abstract: A process of electroplating aluminum comprising mechanically forming a composite aluminum-platable plastic structure, masking any exposed aluminum and thereafter electroplating the platable plastic surface.

Method of electroplating interconnections

Abstract: A method of forming interconnections is described wherein small gaps between contacts are bridged by electroplating metal onto both contacts to form a conductive path therebetween. Many interconnections may be made simultaneously between adjacent contacts by bridging the gap with metal by electroplating.

Method of regulating cathode current density in an electroplating process

Abstract: The invention relates to a method and apparatus for the regulation of cathode current density in electroplating baths, so that optimum deposition characteristics are obtained. The apparatus includes at least one controllable power supply unit, by means of which the plating current or voltage can be adjusted in accordance with the optimum current density J O , for the particular electroplating bath involved. The method includes the steps of measuring and adjusting the values of the plating current or voltage of the power supply unit in accordance with values determined from a graph F defined by the function U = F(I)J O , having the optimum current density J O as a parameter. The function defines the interdependence between the plating voltage and the current, with the J O as a parameter. The method facilitates the regulation of cathode current density to optimum deposition conditions, for electroplating articles having unknown and difficult to determine surface areas. The apparatus includes also a master computer with a memory store for automatically adjusting and controlling the power supply unit.

Method of preparing aluminum wire for electrical conductors

Abstract: Aluminum wire, of either pure aluminum or an aluminum alloy is plated with a firm layer of nickel by passing the wire through a pickling bath of an aqueous solution of phosphoric and hydrochloric acids at a temperature of between 50° and 70° C and then electroplating the wire with nickel.

Process for electro-plating nickel on titanium

Abstract: A process for electroplating nickel on titanium which comprises connecting the titanium as the cathode in an acid solution to form a layer of titanium hydride on the titanium and thereafter immersing the hydrided titanium in a nickel plating solution and cathodically plating nickel thereover.

Trivalent chromium electroplating baths and method

Abstract: An aqueous trivalent chromium plating bath having low temperature stability comprising trivalent chromium ions preferably in a concentration of at least 0.2 M, sulphate ions preferably in a concentration of at least 0.3 M, a weak complexing agent for the chromium ions in a concentration of at least 0.1 M, and fluoride ions in a concentration of at least 0.025 M. The bath preferably also contains chloride ions in a concentration of at least 0.1 M.

Method and composition for electroplating chromium and its alloys and the method of manufacture of the composition

Abstract: A plating solution, the making thereof and the use for chromium plating is disclosed. The solution is an equilibrated essentially aqueous solution of a hexavalent thiocyanatochromium III complex wherein the ratio of the total chromium III to the total thiocyanate is about 1:6. A preferred and improved method of making the solution from a hexathiocyanatochromium salt is also disclosed.

Plating method for memory elements

Abstract: A method for electroplating in a single electroplating bath comprising varying the electric current density so that a non-magnetic plated film and a ferromagnetic plated film are selectively deposited. To achieve this effect the electroplating bath must contain at least about 1 g/l NaH 2 PO 2 .H 2 O.

Electroplating of thick film circuitry

Abstract: The improved circuit composite of the present invention is of the thick film type, but is readily solderable, weldable and bondable to wire without oxidizing. The composite comprises a refractory substrate such as alumina, beryllia or zirconia, a thick printed film pattern of oxidizable electrically conductive metal such as copper, nickel, or silver bonded to the substrate, and a thin electroplated film of non-oxidizable electrically conductive metal, such as gold or platinum, enclosing and adhering to the thick film pattern. The then-electroplated film allows wires and contacts to be soldered, welded or bonded to the pattern, as by ultrasonic or thermocompression bonding, without degrading the quality of the contact area and while permitting removal and subsequent reattachment of such wires and contacts. The method is simple, inexpensive and efficient. It calls for forming the thick film on the substrate and then electroplating the thin film thereover. The method results in durable circuit composites, particularly microcircuit composites of high quality and improved utility.

Solar cell with multiple-metal contacts

Abstract: Solar cell having a contact formed from a titanium group element in contiguous relationship with the cell, a mixture of a titanium group element and a platinum group element overlying the titanium group layer, and a layer of a platinum group element overlying that layer. A body of silver or other contact metal is adhered to the platinum group layer. The three layers may be vapor deposited on the semiconductor body, while the silver layer is more advantageously applied by plating or electroplating.

X-ray tube having focusing cup with non-emitting coating

Abstract: An x-ray tube is described including a focusing cup electrode coated with a high work function material, such as platinum or gold, to prevent the field emission of electrons from such cup. The method of applying the non-emitting coating is preferably sputtering or ion plating, but may also be electroplating followed by vacuum fusion in the case of gold or other low melting point metals.

Gold electroplating process

Abstract: Certain reducible species are found in gold electroplating solutions which interfere with efficient electroplating of gold and make uncertain gold thickness predictions based on current throughput. A gold electroplating process is described which minimizes formation of undesirable reducible species. This process uses an anode of titanium having a coating of the oxides of ruthenium, iridium, rhodium, titanium or mixtures thereof. In addition, a procedure is described for removing such chemical species from the gold plating bath which does not adversely affect the gold electroplating solution.

Process for gold plating

Abstract: The invention is a process for rapidly electroplating certain metals such as gold, nickel, tin-nickel and tin-lead alloys on contact fingers for electronic printed wiring boards. Particularly important is uniform distribution of current amongst the fingers so as to produce uniform metal platings with equal thickness. Also of importance is the provision to alter thickness among the individual fingers so as to plate metal where most needed for particular applications. Uniform and rapid plating are achieved by certain circuit designs together with high parallel flow rates of electroplating solution in the electroplating cell. Both electroplating uniformity and provision for selecting thickness for individual fingers permits savings in amounts of metal used without sacrifices in performance. This is particularly important in the case of gold electroplating because of the high cost and increasing use of gold.

Aluminum terminal and preparation

Abstract: PURPOSE: To prevent a corrosion due to a junction of copper and aluminum, with a jointing of the plated layer strengthened to the aluminum, by such means that nickel be directly electroplated on junction surfaces with copper, silver, tin, solder plated as necessary on its top. COPYRIGHT: (C)1978,JPO&Japio

Device for manufacturing substantially flat dies

Abstract: There is described a method for manufacturing by electroplating substantially flat dies or similar, which comprises adjusting the electric current strength by varying the sparing between the cathode and the anode inside the electrolyte proper.

Apparatus for continuously electroplating on only a single surface of running metal strip

Abstract: In a horizontal-type electroplating apparatus which includes a tank containing an electroplating bath for electroplating onto a single surface of running metal strip, the tank including anodes therein which have a width substantially equal to the width of the strip which passes through the tank, the apparatus also including an electric insulator sheet positioned in contacting relation to the upper surface of the strip which is opposite to the lower surface facing the anodes, the improvement wherein a nozzle for supplying the electroplating solution to the bath in the tank is provided at the bottom of the tank and is oriented to discharge the solution towards the lower surface of the running strip; wherein gas-jet nozzles are positioned to discharge gas towards the zones of the upper surface of the strip which are not contacted by the integral insulator sheet; and wherein an overflow device is provided along the side of the tank to control the level of the plating solution substantially equal to the level of the pass-line of the strip as it runs through the tank; each of these improvements acting to minimize the plating onto the opposite surface which is not to be plated.

Improved performance of GaAs microwave field-effect transistors with via-connections through the substrate

Abstract: Via-connections to source electrodes through the substrate of GaAs Schottky barrier MESFETs have been fabricated in a reproducible manner by means of etching, electroless gold plating, and electroplating. The short gold-plated source connections reduce the common-lead parasitic source inductance by a large factor, resulting in gain increases of 2 db at 4 GHz. At higher frequencies, the improvement over conventionally bonded transistors would become more pronounced.

Zinc electroplating bath

Abstract: An aqueous cyanide-free alkaline zinc bath for electroplating metallic surfaces with mirror-bright zinc coatings, which bath contains zinc ions, alkali metal hydroxides and, as the brightener, a polyalkylenepolyamine which is at least partially alkylated, with alkyl of 1 to 3 carbon atoms, at the basic nitrogens.

Plating method with lead or tin sublayer

Abstract: A nickel or cobalt layer is electroplated from a fluoborate bath directly onto a lead or lead alloy or tin or tin alloy sublayer, which has been electroplated onto a metal surface. Microcracked chrome is electroplated over the nickel or cobalt layer. With a nonconductive plastic substrate, the sublayer is electroplated onto a metal film which was deposited on the plastic by an electroless method. The plated product includes a sublayer of about 0.05 to 2 mils lead or lead alloy or tin or tin alloy, a second layer of about 0.05 to 2 mils nickel or cobalt, and an outer layer of about 0.001 to 1 mil chrome.

Continuous electroplating of alloy onto metallic strip

Abstract: A method of continuously electroplating alloys onto strip and wire. The strip is moved in an essentially mirror symmetrical path through the plating bath with the anode generally bisected by the mirror plane. The distance between anode and strip is smaller within the mirror plane, and larger at strip positions removed from the mirror plane, resulting in essentially uniform current density over the length of the strip immersed in the plating bath and in a homogeneous composition of the plated surface layer.