Two sources of visible room-temperature luminescence were identified in films that contained ion-beam synthesized Si nano-crystals. By comparing luminescence spectra and photoluminescence decay lifetime measurements for Xe+-implanted films and films which contained Si nano-crystals, a luminescence feature was found which was attributed to defects in the oxide matrix. The H passivation of films selectively quenched the matrix defect luminescence. A luminescence which could be attributed to Si nano-crystals was then evident; with a lifetime that was of the order of ms. Upon annealing H-passivated samples again at temperatures below 500C, the intensity of the nano-crystal luminescence increased by a factor of more than 10.

K.S.Min, K.V.Shcheglov, C.M.Yang, H.A.Atwater, M.L.Brongersma, A.Polman: Applied Physics Letters, 1996, 69[14], 2033-5