Electroplating deposition

Electroplating deposition of a thin adherent layer of a metal or alloy onto a substrate by electrochemical reduction of its ions from an electrolyte under application of a cathodic overpotential. 

It is claimed (165) that a composite electroplated deposit of Co plus Mo, regardless of the alloy thickness, provides far from such an active deposit as is achieved by in situ addition of very small amounts of Co and Mo anionic species during cathodic Hj evolution where at least 200 mV of overpotential... 

Finally, let us mention that a variety of anodised, electroplated, deposited and polysurface disc and large area planar alpha and beta standards are available from ... 

Figures 5 and 6 show secondary electron SEM images of the electroplated deposits in cross section and plan view, respectively for samples plated in a solution containing 0.01M-0.02M ethylene diamine. The deposition rate increases between 1.2 and 3.2 mA/cm2. Note that the plating time at 1.2 mA/cm2 is 180 minutes, 90 minutes for the samples plated at 1.8 and 2.4 mA/cm2, and 40 minutes for the sample plated at 3.2 mA/cm2. The grain structure of the deposits also varies with an increase in current density. The sample plated at 1.2 mA/cm2 (Figures 5a, 6a) is gold rich and has a smooth surface containing fine pores about 0.1 pm in diameter, while the samples plated at 1.8 and 2.4 mA/cm2 (Figures 5a, 5b, 6a, 6b) exhibit a columnar structure which becomes more coarse with an increase in current density. The deposit formed at 3.2 mA/cm2 appears to have a mixed structure, the bottom two-thirds having a dense, feathery appearance, while the top third has a fine columnar structure.

Electroplating Depositing a thin layer of metal on an object immersed in a solution by passing an electric current through it. 

Combined method of copper electroplating deposition and low temperature melting for damascene technology. Proceedings of SPIE, Vol. 6260, SPIE, Bellingham, WA, pp. 62601H1-62601H1. 

Copper is etched at further stages in the manufacture of printed circuit boards including, after resist application (1) removal of electroless and electroplated deposits before pattern plating with copper (2) prior to electroplating gold onto edge contacts and (3) final etching of all unwanted copper to leave the desired circuit pattern. 

Tungsten carbide and zirconium diboride electroplates deposited from ion melts by high-temperature electrochemical synthesis can be recommended for an increase in the surface hardness, as well as the wear, abrasive, and corrosion resistance of steel materials. 

The bath model is prepared (as described above), made electrically conductive, and put into a sulphamate nickel bath for an electroplated deposition. Depending on the size, geometry and required wall thickness, the model stays between three to seven weeks inside the electroplated hath including disruptions (to renew auxiliary anodes and insert covers). When reaching the required wall thickness, the process is ended and the mold shell is ground to the outer contour. If necessary, the flange surfaces have to be milled, and fixed bore holes have to be drilled. After thermal or chemical demolding of the bath models, the inner contour is cleaned, the mold is measured, values are compared to the CAD data, and a defined surface treatment is applied. 

At the cathode, the metal ions in solution are reduced to their metallic state and metal is electrodeposited onto the substrate at the anode, solid metal dissolves electrolytically, forming more metal ions that feed the cathodic plating reaction. Electroplating takes place until such time as the current is turned off. The maximum thickness of electroplated deposits is, in theory, only limited by the current utilized to apply the finish, and the length of plating time. However, once the practical thickness limit is exceeded for a specific material, a functional deposit can no longer be obtained. 

Sonoelectrochemistry has been employed in a number of fields such as in electroplating for the achievement of deposits and films of higher density and superior quality, in the deposition of conducting polymers, in the generation of highly active metal particles and in electroanalysis. Furtlienuore, the sonolysis of water to produce hydroxyl radicals can be exploited to initiate radical reactions in aqueous solutions coupled to electrode reactions. 

AppHcations for electroplated indium coatings include indium bump bonding for shicon semiconductor die attachment to packaging substrates and miscehaneous appHcations where the physical or chemical properties of indium metal are desired as a plated deposit. 

Indium chemicals and electroplated metal deposits ate replacing mercury (qv) in the manufacture of alkaline batteries (qv). Indium, like mercury, functions to reduce outgassing within the battery and promotes the uniform corrosion of the anode and cathode while the battery is under electrical load. Indium inorganic chemicals also find use as catalysts in various chemical processes. 

In electroless deposition, the substrate, prepared in the same manner as in electroplating (qv), is immersed in a solution containing the desired film components (see Electroless plating). The solutions generally used contain soluble nickel salts, hypophosphite, and organic compounds, and plating occurs by a spontaneous reduction of the metal ions by the hypophosphite at the substrate surface, which is presumed to catalyze the oxidation—reduction reaction. 

Nickel [7440-02-0] Ni, recognized as an element as early as 1754 (1), was not isolated until 1820 (2). It was mined from arsenic sulfide mineral deposits (3) and first used in an alloy called German Silver (4). Soon after, nickel was used as an anode in solutions of nickel sulfate [7786-81 A] NiSO, and nickel chloride [7718-54-9] NiCl, to electroplate jewelry. Nickel carbonyl [13463-39-3] Ni(C02)4, was discovered in 1890 (see Carbonyls). This material, distilled as a hquid, decomposes into carbon monoxide and pure nickel powder, a method used in nickel refining (5) (see Nickel and nickel alloys). 

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