Abstract
After preparing two kinds of epitaxial Al films by vacuum deposition on NaCl substrutes, we observed thermal behavior during heating in a transmission electron microscope. In (III) single-crystal films, many of local dislocations escaped from the films, and small grains shrinked and disappeared with rise in the temperature above 873K, resulting in the films with a better quality. In polycrystalline films with preferred (III) orientations, normal grain growth occurred with raising the temperature; thereafter, newly nucleated grains showed abormal growth along a heat flow to a larger extentin comparison with the normal growth at a temperature above 873K.
