Ion Beam Enhanced Formation and Luminescence of Si Nanoclusters from a-SiO_x

摘要

The effect of ion beams on the formation of Si nanoclusters from a-SiO_x films and their luminescence properties is investigated. a-SiO_x films with Si content ranging from 33 to 50 at. percent were deposited by Electron Cyclotron Resonance Plasma Enhanced Chemical Vapor Deposition (ECR-PECVD) of SiH_4 and O_2. prior to anneal, some samples were implanted with 380 keV Si to a dose ranging from 5.7X10~(14) cm~(-2) to 5.7 X10~(16)cm~(-2). All films were rapid thermal annealed under flowing Ar environment, and hydrogenated after anneals to passivate defects and to enhance the luminescence of Si nanoclusters. For films with Si content less than 40 at. percent, ion beam greatly increases the PL intensity. Based on the effect of the ion beams dose and the ion specie, we propose that ion beams damage greatly promotes nucleation of small Si clusters from the a-SiO_x matrix.