Control of point defects in semiconductors

The prospects for localized point defect control within II-VI compound semiconductors are considered with reference to doping, thermal annealing, electron and ion beam irradiation and localized 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 behavior following annealing of doped and un-doped CdTe. Controlled directional climb of dislocations within electron beam irradiated Zn se is demonstrated. In view of the differential diffusion of interstitials and vacancies, the prospect of localized semiconductor type conversion is considered