Picosecond carrier lifetime in GaAs implanted with high doses of As ions: An alternative material to low-temperature GaAs for optoelectronic applications

Abstract

Nonstoichiometric GaAs obtained by implantation with 2 MeV arsenic ions at 1015 cm−2 dose is studied. As-implanted samples show a <200 fs lifetime of photocarriers and low resistivity due to hopping, with mobility less than 1 cm2/V s. Annealing of the samples at 600 °C leads to substantial recovery of postimplant damage, as seen from Rutherford backscattering channeling spectra and mobility increase to about 2000 cm2/V s, but photocarrier lifetime is still about 1 ps. These parameters are similar to those of low-temperature GaAs annealed at 600 °C, and make arsenic implanted GaAs an interesting material for optoelectronic applications.