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The paper describes the results of electrochemical investigations of Ni–Co deposition from a sulfamate bath in the presence of boric acid and two additives. The individual deposition of nickel was shown to be partly inhibited by the adsorption of sulfamate ions at low polarization; such inhibition was not observed for cobalt. The introduction of saccharin at 100 ppm, with a wetting agent seems to hinder sulfamate adsorption and Ni deposition departs at less cathodic potentials. The presence of cobalt has no effect on nickel deposition, whereas cobalt deposition is hindered by the presence of nickel in the bath. Galvanostatic deposition was carried out at the surface of a RDE and with a rotating cylinder Hull cell. At low current densities deposits with a Co content of approx. 40% were produced, but this content was shown to decrease with the applied current density. Examination of experimental data showed that cobalt deposition is diffusion-controlled and that Co content decreases with the applied current density relative to the limiting current density.

Copper was deposited on micropatterned electrodes in a parallel plate reactor (PPR) using an industrial acid copper plating bath, and the deposit thickness distributions were measured. The plating bath contained, besides copper sulfate and sulfuric acid as main components, small amounts of sodium chloride and an organic additive LP-1TM. Copper deposition was carried out under various flow conditions (laminar and turbulent) and applied current densities. Three patterns, each of them consisting of a series of parallel copper microtracks, were manufactured on the electrode surface. The pattern position was chosen to be parallel or perpendicular to the flow direction, corresponding to the two extreme positions for the industrial plating process of patterned electrodes, in casu the round pattern tracks of minicoils. A multi-ion model was used to simulate copper deposition from sulphuric acid solutions, taking into account flow phenomena controlling the mass transfer rate, and the deposition kinetics. The differential equations were solved numerically by use of the multidimensional upwinding method (MDUM). Copper deposition on plane electrodes was investigated and compared to cd distributions obtained from MDUM-simulations. For the case of perpendicular pattern position in laminar flow, the deposit growth in the vias was also modelled and simulated numerically.

For beta dosimetry, thin detectors and thin covering foils are used to indicate H(0.07). The photon energy response of these detectors is affected by the material of the detector, as well as of the dosemeter encapsulation. Experiments have shown that in the photon energy range 20 to 50 keV the relative response Ry = R(E)/R(137Cs) for exposure was found to be unexpectly high (Ry = 1.85) for carbon loaded LiF in a finger ring from stainless steel and unexpectedly low (Ry = 0.6) for thin TSEE-BeO detectors on a graphite substrate. Secondary electrons, produced in the surrounding materials contribute significantly to the energy absorption in the thin detector and can be used as the base to optimise photon energy response. The contribution of secondary electrons from different materials in front of the detector was investigated using PE, PTFE, PVC, aluminium, copper and stainless steel. The effect of the dosemeter encapsulation on the photon response depends on the Z value of the material and was found to increase, also for LiF + 1%C. with the mass energy absorption coefficient of the covering material as discussed previously for TSEE-BeO.