Reconstruction and electron states of a Ga2Se3-GaAs heterointerface

It is established by electron microscopy and electron diffraction analysis that the formation of Ga2Se3(110) layers on GaAs(100) and (111) surfaces du ring heat treatment of the latter in selenium vapor is accompanied by the f ormation of transition regions with crystallographic orientations [310] and [(2) over bar (1) over bar (1) over bar], respectively. It follows from an investigation of the spectrum of surface electron states in the resulting heterostructures that a reduction in the density of surface electron states is achieved only after selenium vapor treatment in a narrow interval of tr eatment durations (from 5 min to 30 min under the conditions established in the present study). All the results are discussed on the basis of concepts involving reconstruction of the gallium arsenide surface during chalcogen treatment. (C) 1999 American Institute of Physics. [S1063-7826(99)01806-2].