Arsenic diffusion in Si and strained SixGe1−x alloys at 1000 °C

Results of arsenic diffusion under intrinsic diffusion conditions in Si and SiGe (5, 10% Ge) alloys are presented. Epitaxial Si and compressively strained SiGe structures with buried marker layers of arsenic were grown using Molecular Beam Epitaxy. The concentration profiles before and after Rapid Thermal Annealing at 1000 °C have been measured using SIMS. An enhancement of intrinsic arsenic diffusivity in SiGe compared to Si is observed, in agreement with literature. However, for As in Si0.95Ge0.05 strain seems to compensate the effect of enhancement due to Ge chemical effect although for Si0.9Ge0.1 the chemical effect overcomes the retardation due to strain.