The behavior of Ar plasma-induced defects (inactivation centers), which deactivated Si donors in n-type material, was studied. Photoreflectance spectroscopic analysis, combined with step-wise wet etching, was used to depth-profile these centers. It was found that the point defects which were responsible for these centers underwent electronically enhanced diffusion under the minority carrier injection which was induced by laser illumination. This demonstrated that photo-excitation of carriers by the ultra-violet light from plasma could be the cause of a deep penetration of defect centers to far beyond the ion-stopping range. It was also found that diffusing point defects were trapped by the background defects or impurities, and finally generated complexes which were immobile. This suggested that deactivation might be dominated not by compensation but by the neutralization mechanism.

H.Nakanishi, K.Wada: Materials Science Forum, 1995, 196-201, 1407-12