High-resolution x-ray diffraction investigations of He-implanted GaAs

The isolation of devices via ion implantation is one of the standard procedures in III-V processing, but so far little information is available concerning the degree of damage generated in regions near devices before and after annealing steps. We report on He implantation with typical ion dose and energy ranges into n-GaAs epilayers using high-resolution x-ray diffraction (HRXRD) for characterization. From analysis of rocking curves it is found that up to doses of 1014 cm-2 in the ion energy range of 25-370 keV a rapid thermal annealing treatment at 400 °C is sufficient to remove lattice distortions observed after implantation. The depth of the damaged region estimated by HRXRD is compared to transport of ions in matter calculations and secondary-ion mass spectroscopy measurements.