TRACK ETCHING IN AMORPHOUS METALLIC FE81B13.5SI3.5C2

A review of the presently available results for track etching in metal lic glasses is given. Latent tracks in amorphous Fe81B13.5Si3.5C2 can be selectively etched to surface pores with a wide cone opening angle, Etched tracks have been observed only if the alloy is in the amorphou s and not in the crystalline state. Annealing tests after ion irradiat ion show that track fading occurs for temperatures above 200 degrees C . An etching threshold is observed at a critical energy loss of 3.4 ke V/Angstrom, which is far above the threshold for creating damage (1.3 keV/Angstrom) as observed by resistivity measurements. The etching beh aviour near the threshold shows a transition regime from non-homogeneo us to homogeneous etching. This observation is related to etched track s in insulators. The occurrence of the etching threshold is used to de termine the influence of the distribution of the radial dose of ions h aving various velocities. The experimental results are compared with t hermal spike calculations.