Ionisation stimulated defect annealing in GaAs and InP

GaAs and InP samples were pre-damaged by 600 keV Ge ions at 77 K to obtain different damage levels and then post-irradiated at room temperature with different fluences of 390 MeV Xe ions. The samples were analysed by means of RBS and TEM. In GaAs the large electronic energy deposition causes pronounced annealing within the pre-damaged layers. The relative annealed fraction is nearly constant in a wide range of the pre-damage, it decreases remarkably for very high pre-damage levels, and increases with the Xe fluence. The Xe irradiation results in a local crystallisation of amorphous regions. In InP a slight damage annealing occurs at low Xe fluences, while with increasing dose additional damage is produced. This result is in accordance with previously found ionisation-stimulated damage production in virgin InP.