CORE-LEVEL PHOTOEMISSION-STUDY OF AS INTERACTION WITH INP(110) AND GAAS(110)

We present a comparative core level photoemission study of the interac tion between As and the (110) surfaces of GaAs and InP. In both cases it is found that As forms well ordered overlayers with the periodicity of the substrate surface. The interactions in the two cases are, none theless, very different. The bonding at GaAs is very weak, and the ads orbed species desorbs below 100 degrees C. in contrast, the interactio n with InP(110) is significantly stronger, and at temperatures around 330 degrees C an As-P exchange reaction is indicated and is seen the c ore level spectra. The latter data are interpreted in terms of a recen tly proposed structure model involving an As-covered InAs layer.(C) 19 97 American Vacuum Society.