Interface-Mediated Photostimulation Effects on Diffusion and Activation of Boron Implanted into Silicon

Recent work has demonstrated the existence of nonthermal illumination effects on the diffusion of boron, arsenic, and isotopic silicon ion-implanted into silicon for ultra-shallow junction applications. In some cases, the degree of electrical activation is affected as well. The effects arise from super-bandgap light's direct action on bulk point defects via changes in their charge state. By contrast, the present work demonstrates the existence of a distinct mechanism whereby light acts indirectly on bulk defects via changes at a nearby interface. The changes occur in interfacial annihilation probability and/or electric potential, and affect the efficiency with which the interface absorbs point defects emitted by extended end-of-range defects during annealing.