RADIATION-INDUCED DAMAGE IN GaP BY MeV HELIUM IONS

The creation of defects in GaP bombarded with MeV ⁴He ions has been studied under ultra-high-vacuum condition by Rutherford backscattering/channeling (RBS/C) method, and the absolute damage cross section \sigma_d for GaP has been determined under bombardment of 1.0 MeV ⁴He ions, with the measured value 8.0xl0^-18 cm². Our experimental results suggest that the defect generation rate is strongly related to the surface condition. When the GaP covered with a thin amorphous layer, a significant ion beam annealing effect will be observed. The present results show that for GaP the damage is produced mainly by nuclear collision.