INVESTIGATION OF LATENT TRACKS FROM HEAVY-IONS IN GES CRYSTALS BY HIGH-RESOLUTION TEM

Single crystals of GeS cleaved along the (010) plane were irradiated at GSI UNILAC with very heavy ions at energies of 5.9, 11.4 and 13 MeV/u. High resolution and-bright field observations with a 400 keV transmission electron microscope (TEM) as well as with a conventional 100 keV TEM were carried out. The planar bright field imaging of the ion tracks revealed relatively large amorphous cores of elliptical cross sections, oriented with respect to the crystal lattice. In the surrounding crystal regions strain contrast centres were detected. During the study with TEM the influence of heavy ion tracks on movements of dislocation lines in the crystal was observed. Successive images demonstrate the interaction of the tracks with dislocation lines.