Electron transport across aluminum/ultrathin silicon oxide/phosphorus implanted silicon barriers

Abstract

Schottky barrier diodes are fabricated on silicon surfaces whose impurity concentrations are controlled by ion implantation techniques. The barriers are produced by electron beam evaporation or sputtering of the metal. The forward characteristics of the diodes show that the forward voltage of Schottky barrier diodes made by sputtering is 50–100 mV larger than those made by electron beam evaporation. Electron spectroscopy for chemical analysis measurements show that, for sputtering, the silicon oxide thickness at the interface between the metal film and silicon substrate is 0.2 nm thicker than for electron beam evaporation. Theoretical and experimental studies of Schottky barrier diodes in which the metal and silicon substrate are separated by a thin layer silicon oxide are reported.