The kinetics of fast steps on crystal surfaces and its application to the molecular beam epitaxy of silicon

• DOI: 10.1147/rd.326.0804
• Publication Date: 2010-04-05T14:34:14Z
• Authors: R. Ghez; S. S. Iyer
• Keywords: Supersaturation; Crystal (programming language); Discontinuity (linguistics)

Crystal growth by molecular beam epitaxy (MBE) occurs under conditions of high supersaturation. The classic theory Burton, Cabrera, and Frank (BCF) is based on the assumption that surface steps move slowly. Consequently, it requires modifications to be applicable MBE because velocities may large. In addition, such are asymmetric structures, as observed experimentally field ion microscopy, capture probabilities from above below a step must differ markedly. Hence adatom concentration distribution cannot at equilibrium steps; there, also suffers discontinuity. We propose model treats motion Stefan problem respects its physical asymmetry. Calculations presented which extend complete recently published results had imposed restrictive condition local steps. Step velocity estimated function supersaturation, degree asymmetry, density. Concentration profiles then computed; they found generally skewed. all cases, we show behavior growing crystal convective rather than diffusive when supersaturation can understand extraordinary insensitivity Si changes in temperature orientation.