The general concepts governing the electrochemical deposition of metal films on semiconductors are discussed, and recent results on the fabrication of Schottky junctions consisting of silicon electrodeposited with platinum, copper and gold are presented. In order to obtain good adherent metal films, the density of nuclei should be high and the films should be grown at low current densities where the charge transfer process is rate limiting. This situation can be realized using potential controlled electrochemical deposition. For metal deposition on silicon, the surface should be pretreated in HF to dissolve the oxide layer. Furthermore, the surface should be stable during deposition which can be achieved by tailoring the deposition solutions and by using electrochemical deposition at negative potentials. It is shown that by using this approach, n-type silicon / Pt, Au, and Cu Schottky junctions can be fabricated of a quality comparable to that of junctions prepared by sputter and vapor deposition techniques.

Electrochemical sharpening of metal wires can be achieved by rapid etching in the electropolishing regime. The electropolishing of nickel in I1SO4 glycerine/water solutions was found to be associated with the formation of a salt film at the surface. The shape of the tips was found to be dependent on the etching conditions: low aspect ratio tips were obtained in solutions with high resistivity, whereas high aspect ratio tips were produced in solutions with lower resistivity.* Electrochemical Society Student Member, * * Electrochemical Society Active Member, ied. The results for nickel tip sharpening could be applied for the preparation of the widely used noble metal tips.