Column III-column V sublattice interaction via Zn and Si impurity-induced layer disordering of 13C-doped AlxGa1−xAs-GaAs superlattices

Abstract

Experiments are described employing secondary-ion mass spectroscopy (SIMS) to study the stability of 13C-doped Al0.5Ga0.5As-GaAs superlattices against Zn and Si impurity-induced layer disordering (IILD). The modulation depth of the SIMS 27Al and 13C signals is used as a sensitive probe of column III and column V sublattice interdiffusion. The data show that CAs is much more stable against Zn and Si IILD than the column III superlattice host crystal itself. The minor enhancement of CAs diffusion via the column III disordering agents, which is present to a significant extent for Si IILD but almost nonexistent for Zn IILD, suggests that there is no direct interchange of column III and column V sublattice atoms. The Zn and Si enhancement of carbon diffusion is probably caused by local Coulombic interaction between the diffusing Zn+i and Si+III species and the C−As acceptor.