DEEP-LEVEL TRANSIENT SPECTROSCOPY OF SI SI1-X-YGEXCY HETEROSTRUCTURES/

Deep-level transient spectroscopy was used to measure the activation e nergies of deep levels in n-type Si/Si1-x-yGexCy heterostructures grow n by solid-source molecular-beam epitaxy. Four deep levels have been o bserved at various activation energies ranging from 231 to 405 meV bel ow the conduction band. The largest deep-level concentration observed was in the deepest level and was found to be approximately 2x10(15) cm (-3). Although a large amount of nonsubstitutional C was present in th e alloy layers (1-2 at. %), no deep levels were observed at any energy levels that, to the best of our knowledge, have been previously attri buted to interstitial C. (C) 1998 American Institute of Physics.