An investigation was made of C co-implanted layers that were formed by the high-dose Ge implantation of (100) Si, followed by rapid thermal annealing (1100C, 10s). In the absence of C, the layers (with Ge peak concentrations of about 15at%) were epitaxial and fully strained; but contained extrinsic dislocation loops in the Ge end-of-range region. In C co-implanted samples, the quality of the materials was improved since the formation of defects at the end of range was suppressed and the strain was reduced. The diffusion of minority carriers did not appear to be affected by the presence of secondary defects at the end of range. In C co-implanted material, even if extended defects were not present, a high concentration of minority carrier recombination centers was observed, which strongly reduced the carrier diffusion length.

S.Lombardo, K.K.Larsen, V.Raineri, F.La Via, S.U.Campisano, S.Lagomarsino, A.Kazimirov: Journal of Applied Physics, 1996, 79[7], 3456-63