Visualization by near-field microscopy of the impacts of swift heavy ions in amorphous metallic alloys

The surface of amorphous metallic ribbons (Fe81B13.5Si3.5C2) irradiated wit h swift heavy ions is studied by atomic force microscopy (AFM). Ion impacts are materialized by the formation of hillocks for irradiations at 300 K wi th a high (dE/dx)(e) (above similar to 55 keV nm(-1)). The height of the hi llocks strongly decreases when the samples are aged during 1 year at room t emperature. Conversely, irradiation at 80 K does not induce noticeable modi fications of the surface of the ribbons. The results indicate that the form ation of the hillocks, which are flattened by the sample growth, is essenti ally due to the damage created by electronic excitation in individual ion t racks. (C) 1998 Elsevier Science B.V. All rights reserved.