Molecular processes on the semiconductor surface in the Ge-S system

In this paper we present the results of investigations of two processes that occur on the surface of germanium interacting with sulphur vapour. The first process is etching of the germanium. Analysis of experimental results indicates that a kinetic model which incorporates two competing processes (adsorption of S₂ and desorption of GeS) is most likely. The second process results in the formation of sulphide films on the crystal surface. The composition of these films was determined by chemical analysis and by X-ray microanalysis. The chemical structures of the films and of the Ge-GeS interface were investigated by electron spectroscopy for chemical analysis. The results described in this paper lead us to conclude that the displacement of a surface germanium atom is the rate-limiting step in the growth of the films.