Si-Si pair diffusion and correlation in AlxGa1−xAs and GaAs

Abstract
The Si impurity is diffused into GaAs at temperatures in the range 725≤T≤850 °C. Secondary ion mass spectrometry (SIMS) analysis is used to obtain the Si atom density in the Si‐diffused layers. On the basis of the SIMS data and the observation of a distinct exciton peak in absorption for samples diffused at temperatures ≲775 °C, we argue that in the range nSi≲4×1018/cm3 the Si impurity diffused into GaAs is correlated and is incorporated as Si‐Si nearest‐neighbor pairs.