Indium segregation to dislocation loops induced by ion implantation damage in silicon

Abstract

Indium segregation to dislocation loops and indium co-diffusion were investigated using secondary ion mass spectrometry (SIMS) and a physically-based diffusion model. High doses of As (30 keV, 1×1015 cm2) and B (5 keV, 1×1015 cm2) were implanted in indium-doped Si wafers which were then annealed at 750 °C and 1000 °C in a nitrogen ambient. SIMS profiles showed indium segregation around the implantation damage in both As- and B-implanted Si samples. Indium segregation around the B implantation damage confirms that indium segregation is induced primarily by implantation damage. We present a diffusion model that describes the interaction of indium and dislocation loops and the electric field/chemical ion pairing effect. A simulation that includes this model can predict indium segregation to dislocation loops produced by As/B implantation damage. As/B implants also induce the transient enhanced diffusion of indium. A difference in diffusivity enhancement of indium is shown between As implants and B implants. It is proposed that the difference can be attributed to the difference in the amount of the net excess interstitials, primarily due to ion mass effects.