The effects of reactive atoms on microstructural changes in polycrystalline sintered alpha-SiC thin film specimens irradiated with 30 keV N(2)(+) or 20 keV Ne(+) at RT (room temperature) and isochronically annealed (400-900 degrees C) after irradiation were studied by TEM. Irradiation-induced amorphization occurred during irradiation at RT with both N: and Ne(+) irradiation. Bubbles were also observed to form, but nitrogen bubbles were more difficult to form than Ne bubbles. To investigate the effects of nitrogen on recrystallization behavior, the specimens irradiated with high dose and low dose of N(2)(+) were annealed, respectively. High nitrogen content depressed the epitaxial growth from the crystalline region to amorphous region, while the dependence of the recrystallization behavior on Ne dose was not clearly observed. (C) 2000 Elsevier Science B.V. All rights reserved.