Norihide Nishida

Laser surface alloying of zinc-nickel doubly electroplated films on steel

A new method has been developed in which zinc-nickel doubly-coated films were electroplated onto steel substrates and then irradiated, using a high powered YAG laser with kaleidoscope for surface modification to alloy the zinc-nickel films.

A candidate for interconnection material; Al-Y alloy thin films

Abstract We propose Al-Y alloys as possible candidates for interconnections for silicon integrated circuits, because we have determined that bulk Al-RE (rare-earth) metal alloy systems, particularly in the Al-Y alloy system, possess very small grains, high heat and high corrosion resistance. By use of a co-evaporating method, Al-Y alloy films within the composition range of 0–8.6 wt% (0–2.8 at%) were deposited directly onto (100) Si substrates. These films exhibit a significant decrease in grain size in comparison with pure Al film. Furthermore, the electrical resistivity of the films, which increases with increasing Y concentration in the as-deposited state, tends to decrease to the level of pure Al by annealing.

Corrosion Behavior of Electroplated Zn-Co Alloys from Sulfate Solutions

We studied corrosion by Zn-Co alloys electroplated from sulfate solutions onto iron substrate in a salt spray test (SST) by using scanning electron, X-ray diffraction, and X-ray photoelectron spectroscopy (XPS).We found Zn-Co alloy surfaces corroded by SST to be covered by corrosion products (white rust) consisting of Zn(OH)2, ZnO, Zn5(CO3)2(OH)6, and ZnCl2·4Zn(OH)2 due to the dissolution of Zn. For γ-phase alloys consisting of 10∼20wt%Co, a corrosion product with low electrical conductivity (ZnCl2·4Zn(OH)2) formed mainly with the corrosion product apparently effective subsequently as a barrier against further corrosion. The good corrosion resistance of γ-phase films can be attributed to conversion to a more noble-metal site due to Co concentrating on the corroded surface as corrosion advanced.

Influence of the diluting gas on the formation of titanium boride films deposited by reactive ion plating with diborane

Abstract Titanium boride films were deposited by ion plating using a mixture of argon and 5% diborane, and a mixture of hydrogen and 5% diborane. The TiB2 phase forms by use of both atmospheres, but that which contains hydrogen showed a larger deposition rate and a larger variation of the B Ti ratio.

Structural characterization of Cu-Cr films

Abstract Cu 80 Cr 20 films were deposited by vapor deposition and by ion platings with and without bias. Only the film deposited by ion plating with the bias did form the non-equilibrium single-phase fcc solid solution. By heating above 673 K, phase separation occurred, leading to the formation of two layers, a Cr layer at the surface and a Cu layer in the remaining bulk.