In-Situ Electrochemical Comparisons between GaAs and InP Regarding a Promising Anodic Process in Liquid Ammonia

Abstract

A protective monolayer "phosphazene" like film on InP has been already successfully evidenced by a controlled anodic process in liquid ammonia (NH3 Liq.). In order to understand the formation mechanism of this passivating film, in-situ comparisons of electrochemical interface responses are performed as well on InP as GaAs. Current-voltage and interfacial capacity measurements are explored on both semiconductors. Similarities of electrochemical behaviours between these two semiconductors are striking. But contrary to InP, the initial surface state is electrochemically recovered by an in-situ cathodic treatment on GaAs. This absolute reversible electrochemical behaviour is definitively significant for GaAs.