The anomalous shape of Zn diffusion profiles in GaAs was quantitatively explained. The Frank-Turnbull mechanism was suggested to govern interchanges, between interstitial and substitutional Zn, via Ga vacancies. It was proposed that these vacancies were either neutral or were singly ionized; depending upon the position of the Fermi level. In addition, 2 physical phenomena were proposed. Substitutional Zn thermally generated interstitial Zn-Ga vacancy pairs, and there was pairing between the donor (interstitial Zn) and the acceptor (substitutional Zn). The model furnished good agreement with experimental data.

K.B.Kahen: Applied Physics Letters, 1989, 55[20], 2117-9