The study of heavy-ion damage in pure copper

The results of a transmission electron microscopy study of small vacancy cluster (8 A <= diameter <= 90 A) formation in pure copper, after irradiation with 30 keV Cu+ and W+ ions, are analysed. Cluster visibility is shown to depend on imaging conditions such as the orientation of the foil, the magnitude of the diffraction vector and the deviation parameter, while reliable and accurate determinations of the geometry, density, size and depth distribution of the defect clusters require a combination of micrographs taken under a series of strong-beam diffraction conditions or a combination of strong- and weak-beam conditions. The damage consisted entirely of Frank loops equally distributed on the four brace111 planes. (U.K.)