EFFECTS OF THE ELECTRON-BEAM ON INP(100)

Auger Electron Spectroscopy (AES) is performed to monitor the InP(100) surface evolution while it is irradiated by an electron beam of 5 KeV energy and 10(-3) A.cm(-2) current density. A charge phenomenon appea rs during the irradiation of sputter-cleaned InP(100) by Ar+ at low en ergy (500 eV). The deposition of phosphorus or antimony at room temper ature on cleaned InP(100) is a good way of preventing this charging pr oblem. This is also achieved by the growth of stoichiometric indium ph osphide on InP(100) substrate, from an injection of phosphine and indi um trimethyl whose the ratio V/III is of 50, in a MOCVD (Metal Organic Chemical Vapor Deposition) reactor. The electron beam even acts to st imulate oxidation of the stoichiometric InP(100) surface involving on the top layers, into a well defined oxide such as InPO4 or a contamina tion layer composed of carbon and oxygen. The partial pressure in the spectrometer is about 10(-9) Torr. The incident electrons produce brea king of (In-P) chemical bonds so that the resulting indium fakes part in the oxidation process. The phosphorus is thought to be desorbed fro m the surface.