Transformation of the InP(001) surface upon annealing in an arsenic flux

Abstract

We report experimental study of the transformation of the oxide-coated InP(001) surface during annealing in an arsenic flux. Using the RHEED method, it was shown that an InP1-хAsх layer is formed on the surface. The transformation of an oxidized surface occurs at a temperature higher at about 60°C than the transformation of an atomically clean surface. The activation energy Ea = 1.17 eV of the formation of an arsenic-containing layer was determined. The amount of arsenic substitution for phosphorus at different annealing temperatures was determined, which is 7% at an annealing temperature of 480°C and increases to 41% with an increase in the annealing temperature to 540°C. SEM analysis of surface reveals areas with high arsenic content (InAs islands). The size and density of such regions increases with an increase in the annealing temperature and at 540°C reaches 5.5 × 103 nm2 and 6 × 109 cm−2, respectively. However, despite the local inhomogeneities, the main surface area is covered with a uniform InPAs layer. The area covered with InAs islands occupies about 1.5% of the surface area at an annealing temperature of 540°C.