Abstract
Stereo electron microscopy has been used to obtain depth distributions of vacancy clusters in gold and nickel bombarded with 80-150 kev mercury or gold ions at 295°K and at 80°K. Clusters are found at depths comparable to the ranges of non-channelled ions. The ratio of median cluster depth to Lindhard projected range is 1·0 in gold and 0·5 in nickel. No temperature effect is found. The cluster size distribution does not vary significantly with depth.