Abstract: A method for making integrated circuit wafers wherein the wafer has vias or other openings in the wafer which openings have a barrier/adhesion or other metal layer which is metallized to form the circuit comprising activating the metal layer and then sensitizing the metallic layer using a sensitizing displacement composition comprising preferably an alkaline palladium non-ammonia nitrogen (ethylene diamine) complex which is contacted with the wafer at a specially controlled pH. The wafer is activated using an activation solution which contains a complexing agent for any dissolved metal. The sensitizing solution also preferably contains a complexing agent for dissolved metal and preferably contains a second complexing agent such as EDTA to solubilize base metal contaminants.

Abstract: A method of removing metal from a feedstock solution containing dissolved metal ions which comprises passing the feedstock through an annular gap, the inner surface of which is cathodic to the metal ion and the outer surface of which is anodic in such a way that the flow is turbulent.Also claimed is an apparatus for removing metal from a feedstock which comprises a reactor afforded by an inner cathode tube, and an outer anode tube spaced therefrom by a narrow annular gap, direct electric current supply means to the anode and cathode, pump means for pumping feedstock into the said annular gap at high flow rates, a holding tank, pipe work connecting the holding tank to the said pump means and the pipe work connecting the end of the annular gap remote from the pump to the holding tank.

Abstract: A low solids, solvent free liquid aqueous degreasing concentrate composition having high free alkalinity which includes from about 20% to about 40% by weight of an alkali builder constituent; from about 15% to about 25% by weight of a wetting agent mixture comprising; from about 60% to about 85% of an anionic or amphoteric wetting agent selected from the group consisting of anionic surfactants and amphoteric and anionic hydrotropes and from about 15% to about 40% non-ionic wetting agents; and the remainder water.

Abstract: A process for forming improved chromate conversion coatings on zinc surfaces by treating the zinc surface with an aqueous acidic chromating solution which contains hexavalent chromium and a soluble inorganic salt which has an cation which will form an insoluble organic silicate and, thereafter, treating the thus-formed chromate conversion coating with an aqueous alkaline silicate solution which contains a soluble alkali metal silicate and fluoride ions.

Abstract: A gold or gold alloy plating composition comprises: a source of gold ions such as potassium gold (I) cyanide; optionally a source of alloying metal (e.g. nickel or cobalt) ions, for example as a sulphate; optionally a complexing agent for the alloying metal ions if present, such as citic acid or oxalic acid; and a rate promoting additive compound of general formula IA or IB: ##STR1## wherein: each of R.sup.1 and R.sup.2 independently represents a hydrogen or halogen atom or a formyl, carbamoyl, C.sub.1-4 alkyl, amino, phenyl or benzyl group, wherein the alkyl, phenyl and benzyl moieties may optionally be substituted with one or more hydroxy or amino groups or halogen atoms;R.sup.3 represents a C.sub.1-6 alkylene radical which may optionally be hydroxylated; andQ represents --SO.sub.2 -- or --CO--.

Abstract: The invention relates to an activating composition for the electroless plating of non-conductive surfaces, in particular electronic printed circuit boards.The composition contains a metal complex in which the ligand consists of a quaternary nitrogen compound, especially a compound in which nitrogen forms part of a heterocyclic system and is quaternarized with a radical comprising an acid residue carrying a negative charge, for example a sulphonated group.The invention also concerns a method for the electroless plating involving the use of such composition, preceded by a preliminary treatment of the substrate and followed by the reduction of activating metal.The activating composition according to the invention allows to fix firmly the activator metal to the substrate.

Abstract: A process for electrodespositing a conductive material on a substrate is disclosed which comprises movably mounting the substrate in a first conductive liquid electroplating bath which contains the conductive material, maintaining substantially constant conditions of temperature and liquid circulation in the first bath, passing an electric current through the substrate and the first bath so as to deposit the conductive material on the substrate, periodically transferring the substrate to a second liquid bath, the second bath containing a liquid of the same composition or lower concentrations of dissolved ingredients as compared to the first bath, weighing the substrate when immersed in the second bath and calculating therefrom the weight in air of conductive material deposited, returning the substrate to the first bath, and continuing the plating in a series of stages of plating, weighing in liquid and plating until the desired deposit is built up.Apparatus for carrying on the method is also disclosed.

Abstract: A method for making printed circuit boards wherein the resistance of catalyzed nonconductive surfaces to solutions used in the processing stages, e.g., KOH used to remove an etch resist covering through-holes and the desired circuit lines, is enhanced by treating the catalyzed surface with an accelerator to activate the catalyst, treating the accelerated surface with a reducing agent, followed by baking.

Abstract: An improved process for purifying a nickel plating bath including a pyridine composition as an additive and which bath contains a breakdown product of the pyridine composition. The process has the following steps:a. adjusting the pH of the nickel plating bath to a pH of equal to or greater than 5.0;b. adding an effective amount of an oxidizing agent; andc. removing the breakdown product from the nickel plating bath.

Abstract: The production of uniformly blackened nickel deposits for decorative or functional purposes can be achieved by depositing nickel from an electroless nickel plate composition or electrolytically followed by forming a conversion coating on the electroless nickel deposit in a chromate bath which includes nitrate ions.

Abstract: A composition for removing a layer of tin, lead or tin/lead alloy from a copper substrate such as a printed circuit board comprises an aqueous solution of nitric acid and ferric acid and also contains anthranilic acid to inhibit the degree of attack on the copper substrate. A surfactant, such as a mixture of cocoamine and an ethoxylated fatty alcohol or a mixture of a phosphate ester and an ethylene oxide/propylene oxide copolymer, may also be present to improve the brightness of the remaining copper.

Abstract: A process for electroplating copper from an aqueous alkaline non-cyanide bath has improved resistance to degradation. At least a portion of the plating bath is subjected to electrolysis by an insoluble anode to which the current is controlled independently from the current to the soluble copper anode in order to reduce the level of bath impurities and maintain the quality of the deposit.

Abstract: An improved aqueous acidic electrolyte suitable for electrodepositing zinc alloys comprising a combination of zinc and at least one metal selected from the group consisting of nickel, cobalt, iron, and mixtures thereof incorporating an effective amount of an additive agent for providing improved grain-refinement and enhancing the adjustment of the codeposition of the alloying metals in the zinc alloy deposit. The additive agent comprises a bath soluble polyhydroxy compound having three or more hydroxyl groups at least one of which is substituted with a polyoxyalkylene group.The present invention further encompasses the process of employing the aforementioned electrolyte for the deposition of functional and decorative zinc alloy electrodeposits.

Abstract: An aqueous composition is provided for treating a laminate in the manufacture of a printed circuit board, the composition comprising a wetting agent, which has a positively charged quaternary nitrogen atom, and a reducing agent which is compatible with the wetting agent. Preferably the reducing agent is hydroxylamine or one or more of its salts, but oxalic acid or one or more oxalates may, alternatively or as well, be used. The compatibility of the wetting and reducing agents enables the number of process steps to be reduced.

Abstract: An aqueous initiator solution and process for rejuvenating such initiator solutions and for prolonging the useful operating life thereof by which copper and copper alloy substrates are treated therein to render them receptive to a subsequent electroless nickel plating step. The detrimental effects of progressive contamination of such aqueous initiator solutions with metal ion complexing agents during commercial use and/or precipitation of the noble metal ions which pregressively impairs the oprativeness of such activator solutions is overcome in accordance with the present invention by the addition of controlled amounts of ferric ions effective to maintain at least a sufficient portion of the noble metal ions in solution in a noncomplexed condition whereby the initiator solution is effective to pretreat the copper substrate prior to electroless nickel plating.

Abstract: A method of passivating a zinc-cobalt alloy, which alloy has a cobalt content of 0.1-2%, by contacting the alloy with an aqueous composition which has a pH of 0.5-2.5 and contains hexavalent chromium, hydrogen ions to provide the pH, chloride ions and sulfate ions and which may also contain nickel and/or cobalt ions.

Abstract: An improved electrolytic apparatus and process particularly applicable for high-speed electrodeposition of a metallic plating on a substrate such as on a printed wiring board of the type employed in the electronic industry. The apparatus employs a manifold assembly adapted to be immersed in the electrolyte and positioned adjacent to each of the anodes immersed therein for withdrawing electrolyte past the anode to provide a controlled rate of flow across the anode surface to achieve a substantially uniform mass transport rate across the fluid film on the surface of the anode. The apparatus is also adapted for returning at least a portion of the withdrawn electrolyte to the tank which can be arranged so as to impinge upon the article being plated.

Abstract: An improved aqueous acidic electrolyte suitable for electrodepositing zinc alloys comprising a combination of zinc and at least one metal selected from the group consisting of nickel, cobalt, iron, and mixtures thereof incorporating an effective amount of an additive agent for providing improved grain-refinement and enhancing the codeposition of the alloying metals in the zinc alloy deposit. The additive agent comprises a bath soluble terminally substituted polyoxyalkylene compound derived from the sulfation, amination, phosphating, chlorination, bromination, phosphonation, and sulfonation as well as combinations thereof;(a) The polymerization of alkylene oxides selected from the group consisting of ethylene oxide, propylene oxide, glycidol, butylene oxide and mixtures thereof; and(b) the alkoxylation of mono and polyhydroxy compounds selected from the group consisting of hydroxyl containing alkyl, alkenyl, alkynyl, aryl, as well as mixtures thereof.

Abstract: An aqueous bath suitable for electrodepositing zinc and alloys of zinc including zinc-nickel, zinc-cobalt, zinc-nickel-cobalt, zinc-iron, zinc-iron-nickel, zinc-iron-cobalt, and zinc-nickel-cobalt-iron containing a brightening amount of an AABB-type polyamide brightener in an amount effective to produce an electrodeposit of the desired brightness. The invention further contemplates the process of electrodepositing zinc and zinc alloys of the foregoing types on a conductive substrate employing the aqueous electrolyte.

Abstract: The difficulties associated with electroplating palladium metal or alloy deposits from palladium diammino dichloride, palladium diamino dinitrite and palladium triammino sulphite baths can be avoided by plating from palladium baths containing oxalate. The palladium and oxalate may be in a single complex, such as palladium diamino oxalate, (Pd(NH.sub.3).sub.2 C.sub.2 O.sub.4), palladium tetraamino oxalate (Pd(NH.sub.3).sub.4 C.sub.2 O.sub.4) or an ammonium or alkali metal salt of palladium dioxalate (M.sub.2 Pd(C.sub.2 O.sub.4)).sub.2), where M represents an ammonium or alkali metal cation.Alloying metal ions may also be present, as may an electrolyte, a brightener and/or a stress reducer.