Monte Carlo simulation of L11-type ordering due to surface step migration in the epitaxial growth of III-V semiconductor alloys

Abstract We investigated L1 1 -type ordering due to surface step migration in III-V semiconductor alloys of ( A 0.5 B 0.5 ) III C V , using an Ising-like crystal growth model. A surface step along the [1 1 0] direction (the [1 1 0] step), which has a preference for unlike-atom pairs along the step, bears ( 1 11) and (1 1 1) variants (CuPt B -type) of the four possible L1 1 variants. On the other hand, a surface step along the [110] direction (the [110] step), which has a preference for like-atom pairs, produces either of the two CuPt B -type variants depending on the direction of the step motion. Antiphase boundaries are inserted parallel to (001) planes in the former case, and ( 1 11) or (1 1 1) in the latter case. The ordering rate in the case of the [110] step is larger than that for [1 1 0] step migration. These results explain well the previous experimental results obtained by transmission electron microscopy.