Radiation damage in InSb by alpha particle implantation

Abstract

Radiation damage in InSb as a result of implanted helium ions has been investigated using RBS/channeling. {111} InSb samples were implanted with 50 keV He + up to a dose of 10 17 ions/cm 2 at temperatures from 77 to 525 K and rates varying from 2.2 × 10 13 to 2.6 × 10 14 ions cm −2 s −1. The formation of stable radiation defects depended on the temperature during implantation, the dose and the dose rate. No dechanneling due to radiation defects was observed after low dose rate implantation of samples heated to 200°C and above. In all other cases, the extent of dechanneling varied from a slight increase for samples implanted at elevated temperatures to amorphisation in samples implanted at 77 K, at doses higher than 2.5 × 10 16cm −2. The results of RBS/channeling and TEM indicate that the stable defect complexes are preferentially vacancy dislocation loops. No evidence for the presence of helium was found near the surface of any of the samples. Finally, the results of annealing radiation defects, both isochronally as well as by pulsed electron beam, are presented.