Oxide film growth on GaAs and silicon substrates by anodization in oxygen plasma and its application to devices and integrated circuit fabrication

Abstract

The major achievements of the Department of Electronic Engineering, University of Tokyo, in the growth of native oxide films on GaAs and silicon substrates by anodization in an oxygen plasma, together with the feasibility of their application to the fabrication of devices and integrated circuits, are reviewed. Two advantages of this technology over thermal oxidation are the low substrate temperature and the fast oxidation rate. The low substrate temperature prevents the evaporation of arsenic oxide from the GaAs substrate during oxidation and makes it possible to produce a good native oxide film on the substrate. The generation of stacking faults and the redistribution of impurities in the silicon substrate were not observed because of the low substrate temperature. The practical importance of this technology was demonstrated by fabricating GaAs insulated gate field effect transistors and also by showing a very small structure shaped like a bird's beak on the periphery of the mask for selective oxidation.