On the nature of the silicon activation efficiency in liquid-encapsulated Czochralski-grown GaAs by photoluminescence

The shallow defect evolution in Si-implanted and -annealed liquid-encapsulated Czochralski-grown GaAs is investigated by photoluminescence experiments. Three major emission lines are found. The first emission line located at 1.492 eV corresponds to the SiGa-CAs radiative recombination. The remaining two lines located at 1.44 and 1.40 eV are shown to correspond to GaI-SiAs and VAs-SiAs radiative recombinations, respectively. The effects of these three shallow centers on the silicon activation efficiency are discussed with respect to different annealing and implantation conditions.