DISTRIBUTION OF SILICON OVER SUBLATTICES IN SEMICONDUCTING A(3)B(5) COMPOUNDS

The stable site of Si substitutional impurities in GaAs and AlAs at T= 0 K is determined on the basis of an analysis of the energy of solutio n of silicon, and of the energies of formation of intrinsic defects an d the reaction energies of their interaction obtained by calculating t he total energy of the disordered compounds. These calculations indica te that amphotericity and vacancies have an effect on the distribution of Si, At low Si concentrations, Si in GaAs is located on the sublatt ice of the group III element, and in AlAs, on the sublattice of the gr oup V element. (C) 1997 American Institute of Physics.