The prospects for localised point defect control within II-VI compound semiconductors are considered with reference to doping, thermal annealing, electron and ion beam irradiation and localised strain. Interstitials and vacancies generated within electron beam irradiated II-VI compounds interact and coalesce in a TEM foil to form voids decorated by metallic precipitates and the processes of CdTe chemical decomposition are examined. Ion beam and electron beam irradiated material show clear differences in behaviour following annealing of doped and un-doped CdTe. Controlled directional climb of dislocations within electron beam irradiated ZnSe is demonstrated. In view of the differential diffusion of interstitials and vacancies, the prospect of localised semiconductor type conversion is considered.

Irradiation effects of high-energy electrons and protons, and 60Co gamma-rays on InP-related materials have been examined in comparison with those of GaAs and Si. Superior radiation-resistance of InP-related materials and their devices compared to GaAs and Si has been found by using deep-level transient spectroscopy (DLTS), photoluminescence (PL) and properties of devices such as solar cells and lightemitting devices. Moreover, minority-carrier injection enhanced annealing phenomena of radiation-induced defects in InP-related materials have also been observed even at low temperature of around 150K.

This paper provides a brief overview of some issues relating to the microstructure of irradiated silicon which are of importance to the semiconductor industry. The nature of ion-induced disorder and conditions for amorphization are initially treated since the starting microstructure can strongly influence subsequent annealing behaviour, particularly removal of residual defects, dopant diffusion and electrical activation. The use of implantation-induced disorder as a means of removing metallic impurities, so called gettering, is also an issue of major current interest for improved performance of devices. Some new gettering results are discussed.

We discuss results of molecular dynamics computer simulation studies of 3 keV and 5 keV displacement cascades in β-SiC, and compare them to results of 5 keV cascades in pure silicon. The SiC simulations are performed with the Tersoff potential. For silicon we use the Stillinger-Weber potential. Simulations were carried out for Si recoils in 3 dimensional cubic computational cells with periodic boundary conditions and up to 175,616 atoms. The cascade lifetime in SiC is found to be extremely short. This, combined with the high melting temperature of SiC, precludes direct lattice amorphization during the cascade. Although large disordered regions result, these retain their basic crystalline structure. These results are in contrast with observations in pure silicon where direct-impact amorphization from the cascade is seen to take place. The SiC results also show anisotropy in the number of Si and C recoils as well as in the number of replacements in each sublattice. Details of the damage configurations obtained will be discussed.