STRUCTURE, MORPHOLOGY AND MELTING HYSTERESIS OF ION-IMPLANTED NANOCRYSTALS

Investigations of nanosized metal and semimetal inclusions produced by ion implantation in aluminium are reviewed. The inclusions are from 1 nm to 15 nm in size and contain from 80 to 100000 atoms. Embedded cry stallites, which are topotactically aligned with the surrounding matri x, may not be produced in this size range by any other method. The inc lusions offer unique possibilities for study of the influence of inter faces on the crystal structure of the inclusions as well as on their m elting and solidification behaviour. Studies are made with transmissio n electron microscopy (TEM), electron- and X-ray diffraction and in si tu RBS-channeling measurements. Bi, Cd, In, Pb and Tl inclusions all s how a substantial melting/solidification temperature hysteresis, which , in all cases except for Bi, is placed around the bulk melting temper ature, while bismuth melts below that temperature.