Distribution of gettering centres at a buried amorphous layer in silicon

A buried amorphous layer in Si has been investigated by means of metal gett ering before and after rc crystallization. Metal impurities, especially Cu atoms. are intentionally introduced and accumulated in damaged regions of S i, The measured Cu depth distributions have been compared to the correspond ing strain profiles and the microstructure of the Si lattice, The buried am orphous layer has been found to act like a diffusion barrier for the Cu ato ms. Cu gettering takes place at the crystalline side of the amorphous-to-cr ystalline (a/c) interface, In this region a Si lattice expansion is observe d. After recrystallization of the amorphous layer Cu gettering occurs as we ll outside of the former amorphous layer, mainly at the interfaces. The beh aviour of Cu atoms in Si seems to be: correlated to the supersaturation of self-interstitials. (C) 1999 Elsevier Science B.V. All rights reserved.