Dislocation Related Photoluminescence in Silicon

Dislocation related photoluminescence in Si and SiGe is attributed to stable interstitial clusters bound to 60^∘{} dislocations. Density functional based total energy calculations in Si give binding energies between 1.5 and 3.6 eV for I₃ and I₄ clusters with 90^∘{} and 30^∘{} partials. They possess donor levels around Eᵥ+0.4eV which are consistent with deep level transient spectroscopic studies on p-Si. It is further suggested that the clusters would act as the obstacles to the movement of dislocations which may have been observed in recent transmission electron microscopy studies.