Reducing Dislocation Density by Sequential Implantation of Ge and C in Si

Abstract

AbstractCarbon implantation was performed after high dose(5 x 1016/cm2) Ge implantation into [100] oriented Si substrates to study the effect of sequential implantation on dislocation nucleation. When the nominal peak concentration of implanted C is over 0.55 at%, Dislocations in the SiGe layer containing C are considerably reduced in density after solid phase epitaxial(SPE) annealing at 800°C for 1 hour, compared to the SiGe layer without C. These results suggest that during annealing, C atoms compensate the Geinduced misfit strain which causes dislocation generation in the region of peak Ge concentration. Channeling spectra obtained by RBS analysis show only 5% to 6% minimum back scattering yield as C atoms suppress the dislocation generation.