Effect of heat treatment on the state of Si impurity in GaAs studied with the photoluminescence technique

Abstract

The effect of heat treatment of Si-doped GaAs was investigated with photoluminescence (PL) measurement. The dependence of PL spectra on the carrier concentration due to Si shows that the PL lines in the wavelength range between 950 and 1500 nm are classified into two types depending on whether the carrier concentration is lower or higher than approximately 7×1017 cm−3. There is also a similar behavior for PL spectra in the bound exciton wavelength region between 800 and 950 nm. The characteristic carrier concentration is about 6×1017 cm−3, and is related to the onset of overlap between wavefunctions of excitons bound to Si impurity.