Chromium and Manganese Redistribution in Semi‐insulating GaAs

Abstract

Cr and Mn redistribution in various semi‐insulating normalGaAs substrates annealed with or without encapsulation have been investigated quantitatively using secondary ion mass spectrometry (SIMS) and photoluminescence (PL). Mn was incorporated into Cr‐depleted sites (Ga vacancies). Cr out‐diffusion can be explained by simple diffusion theory having critical Cr depletion concentration under which no Cr depletion and Mn accumulation occur. While stress‐enhanced diffusion takes place without Mn incorporation in capped annealing, a large Cr out‐diffused area appears in the case of capless (face‐to‐face) annealing of high‐dose implanted normalGaAs . This may be attributed to defects and surface dissociation.