THERMAL AND PHOTON-ASSISTED INTERACTION OF AMMONIA, SILANE AND OXYGEN WITH INDIUM-PHOSPHIDE SUBSTRATES

The first stages of the interaction between InP substrates and gases used in chemical vapor deposition processes (NH3, SiH4 and O2) with and without the assistance of uv illumination have been studied for the first time in an uhv environment by surface techniques. Photo-assisted NH3 exposures lead to a nitrogen uptake in opposition to thermally-assisted exposures. Photo or thermally-assisted SiH4 exposures partly remove the native oxide and drive silicon atoms to form covalent bonds to InP. Successive exposures to SiH4 and O2 build the first silica layers. © 1990 Pergamon Press plc.