Probing grain boundaries in As-doped polycrystalline silicon

Abstract

Using ¹¹¹In–¹¹¹Cd perturbed angular correlations, we investigated the behaviour of In in heavily As-doped polycrystalline silicon. The nuclear In tracers were either introduced by means of grain boundary (GB) diffusion or ion implantation. We find, that the in-diffused In tracers exclusively probe GBs which give rise to a broad distribution of static quadrupole frequencies. The implanted tracers exclusively probe Si bulk material, where they encounter As-dopants during thermal annealing and form the well-known In–As complexes #1 and #2, and the previously unknown complex #4 (eQV_zz=117 MHz, η=0) which involves three As atoms on nearest neighbor sites with respect to the probe. The implications of the present experiment on acceptor doping and GB probing are discussed.