PHOTOLUMINESCENCE ENHANCEMENT BY EXCIMER-LASER IRRADIATION IN SILICON-OXIDE FILMS PREPARED BY PULSED-LASER ABLATION

Silicon oxide films were prepared at room temperature by pulsed laser ablation using an ArF or KrF excimer laser in a gas mixture of He and O-2. The effect of an ArF excimer laser irradiation on the deposited f ilm was investigated. As-deposited transparent films containing Si cry stallites with sizes greater than 10 nm show photoluminescence. Howeve r, after laser irradiation with 1000 shots, the photoluminescence (PL) intensity was increased by two orders of magnitude. The PL spectrum i s centered around 570 nm (2.2 eV). The origin of the large PL enhancem ent is discussed. (C) 1998 Elsevier Science B.V. All rights reserved.