Planarized solid-state epitaxial growth of Si and its effect on Schottky barrier diodes

Abstract

Planarized solid-state Si epitaxy can be grown controllably from Si-doped Al thin films by first depositing a very thin high-temperature underlay film of pure Al on the substrates. It is proposed that both Si pits, in pure Al contacts and Si mesas, in Si-doped Al contacts, nucleate and grow at local defect sites in the native SiO2 on the Si substrate; elimination of the sites leads to planar Si epitaxy structures. The electrical effect of the planar structures, which are p doped with Al, on n-type Schottky barrier diodes is similar to the thin-layer-plus mesa structures which are characteristic of conventionally processed Si-doped Al Schottky diodes after heat treatment. The planarized structures should, however, lead to more uniform and controllable results.