Electrical activation and local vibrational mode from Si-implanted GaAs

Abstract

Local vibrational modes of lattice site Si implanted in GaAs were studied by laser Raman spectroscopy. From the dependence of the intensity of the local vibrational modes due to Si at As sites and Si pairs at Ga and As sites (SiGa-SiAs) on annealing temperature, implanted Si are considered to occupy the lattice sites with the structural recovery by annealing at lower than 550 °C, and form SiGa-SiAs pairs at higher than 550 °C besides the electrically active Si probably in Ga sites. The depth profiles of the intensity of the local vibrational mode and carrier concentration obtained after annealing at 850 °C indicate that Si at As sites prevent the generation of carriers, and Si at Ga sites have no contribution to the generation of carriers if they form the pairs with the nearest-neighbor Si at As sites.