Segregation of boron to polycrystalline and single-crystal Si1 x yGexCy and Si1 yCy layers

Strong boron segregation to polycrystalline Si1 x yGexCy alloys from Si has previously been reported [MRS Symp. Proc. 669 (2001) J6.9]. In this study, we investigate potential mechanisms for this effect.We find that comparable segregation also occurs in both polycrystalline Si1 yCy and single-crystal Si1 x yGexCy, indicating neither Ge nor grain boundary effects are needed for it to occur. In addition, the stability of the electrical properties of polycrystalline Si1 x yGexCy with annealing suggests that inactive B–C defects are not forming. Point defect gradients are presented as a mechanism consistent with the electrical data. # 2003 Elsevier B.V. All rights reserved