Epitaxial Al contacts on Si(111) are fabricated by electron beam evaporation at various substrate temperatures around 250 °C. They are observed by high-resolution transmission electron microscopy. Schottky barrier heights (SBHs) of the contacts are measured using current-voltage and capacitance-voltage methods. In the case of single-crystalline Al film, the SBH does not change and its spatial distribution remains homogeneous up to an annealing temperature of 550 °C. In contrast with this, for an epitaxial Al film containing grain boundaries, the spatial distribution of the SBH becomes inhomogeneous above 400 °C. This is attributed to Si diffusion along the grain boundaries in the Al film.

No abstract

No abstract

The effects of electrically inactive ion implantation in n-type GaAs1−xPx (x≃0.38) on photoluminescence intensity have been studied. Improvement of the photoluminescence efficiency for the near-band-gap transition was achieved by a group-III element (B and Ga) ion implantation at 1013 cm−2. Group-V element (As) ion implantation led to deterioration of the efficiency to the same degree or more than group-VIII element (Ar) ion implantation. The results suggest that the efficiency improvement is attributed to a decrease in the concentration of the ’’killer’’ center, probably associated with the Ga vacancy included in the as-grown GaAsP crystals.

No abstract