Dislocation motion in Sb-doped SiGe on Si substrate

We have successfully grown antimony-doped Si _1-xGe _x epi-films with different doping level and a boron-doped one on Si (001) substrate. Using these samples, we have investigated the effect of these impurities in Si _1-xGe _x epifilm on dislocation velocity. Although dislocation velocities in the B-doped SiGe film were comparable to those in the undoped one because of the low concentration of B, those in Sb-doped samples are remarkably enhanced, which is qualitatively similar to the effects in bulk Si. The reduction of the activation energy of dislocation motion depended on the doping level of Sb and the amount of the reduction was 1.0 eV in the highest Sb-concentration film. This value is significantly larger than those reported in bulk Si. The velocities in the lowest Sb-concentration samples are also enhanced though the samples are thought to be electrically intrinsic at the temperatures where dislocation velocities were measured. Therefore, the large activation energy reduction is possibly attributed to multiple effects of the Fermi level change and other characteristic effects of the SiGe epifilm.