Depth profile of the microhardness in helium implanted GaP

Abstract
Depth profiles of the damage density and the microhardness are measured in GaP single crystals implanted with 1 MeV helium ions. From an analysis of the experimental data it follows that the microhardness increases up to a damage density of about 16% due to point defect hardening. At higher damage densities the microhardness decreases rapidly, probably due to the formation of extended defects.