Surface migration of group V atoms in GaAsP grown on GaAs channeled substrates by molecular beam epitaxy

Surface migration of group V atoms (As and P) during molecular beam epitaxy was investigated for the first time by measuring lateral profiles of phosp horus content in GaAsP layers grown on (100) GaAs channeled substrates (CSs ) with 12-16 mu m wide (n11)A side-slope facet region (n = 3, 4, and 5) usi ng As-4 and P-2 beams. The P content x of the GaAs1-xPx layer on the (411)A side-slope region was 43% smaller (x = 0.11) than that on the (411)A flat substrates, while P contents of GaAsP layers on (311)A and (511)A side-slop e regions were larger than those of GaAsP layers on a corresponding hat sub strate. The observed lateral P content profile was well reproduced by simul ation based on a conventional surface migration model. The migration length s of As atoms, L-As, were determined as L-As((411)A) = 18 mu m, L-As((100)) = 28 mu m, L-As((511)A) = 33 mu m, and L-As((311)A) = 35 mu m, by comparin g the observed and simulated profiles. (C) 2000 American Vacuum Society. [S 0734-211X(00)05403-2].