ESCA and electron diffraction studies of InP surface heated under As molecular beam exposure

Chemical composition of InP substrate surface heattreated under As molecular beam exposure in an ultrahigh vacuum chamber was studied with ESCA, and surface reconstruction of the substrate was examined by in-situ electron diffraction. The InP substrate heated under the exposure of As molecular beam has mirror surface up to 5900C while the surface of InP heated above 4000C in vacuum is roughened. The ESCA study shows that thin InAs layer (thickness<20A) is formed on the surface of InP heated above 5000C under the exposure of As. The electron diffraction study indicates that the InP is cleaned at about 5000C in As pressures of 10-7 - 10-5 Torr. The InP surface is prevented from thermally decomposing by the coverage of the InAs layer, which may be formed through the following process: 2InPO4 + As4 → 2InAs + P2O5 + As2O3. (author)