ANGLE-RESOLVED SIMS STUDIES OF ALXGA(1-X)AS(001)(2X4)-SURFACE RECONSTRUCTION

Angular distributions of Al+ and Ga+ ions desorbed by keV particle bom bardment have been measured from a modified AlxGa(1-x)As {001} (2 x 4) surface reconstruction. This surface was prepared from the GaAs{001} c(4 x 4) surface by deposition of one monolayer of aluminum in situ vi a molecular beam epitaxy. The surface was then annealed to 550 K produ cing a (2x4) reconstruction. By comparing experimental angular distrib ution results with molecular dynamics simulations of the bombardment p rocess, we show that Al and Ga segregate into different layers of the prepared (2 x 4) surface. (C) 1997 Elsevier Science B.V.