Effects of ion implantation and thermal annealing on the photoluminescencein amorphous silicon nitride

When amorphous silicon nitride films are irradiated by a KrF excimer laser, they exhibit broad photoluminescence (PL) centered around 2.4 eV. The PL i ntensity gradually decreases and the PL peak energy shifts to a lower energ y with an increase of the implanted dose of Ar+ ions. This means that the P L consists of two components with peak energies at 2.66 and 2.15 eV and tha t implantation-induced defects such as vacancies are not the PL centers. Th e PL intensity is found to decrease if the film was thermally annealed, whi le the decreased PL intensity of the ion-implanted film recovers by the the rmal annealing. Based on these results, it is concluded that the defects ge nerated by hydrogen release or bond breaking act as nonradiative recombinat ion centers that quench the PL. (C) 1999 American Institute of Physics. [S0 021-8979(99)03609-9].