Electron irradiation effects in Si observed at 4.2-25 K by means of in situ transmission electron microscopy

We have observed electron-irradiation effects in Si at low temperature, uti lizing in situ transmission electron microscopy. Amorphization is induced i n crystalline silicon (c-Si) by high-energy electron (MeV) irradiation at l ow temperatures. The mechanism of amorphization in Si is discussed in terms of self-interstitial clustering. In addition, we have also observed the el ectron (0.3 MeV) irradiation effects at 4.2 K in c-Si by means of high-reso lution transmission electron microscopy. We have found that numerous defect s of a few nanometer in diameter are introduced. The characteristics of the defects differs from those of the known interstitial clusters such as the {113} defects. The accumulation of the defects never leads to amorphization . (C) 1999 Elsevier Science B.V. All rights reserved.