Optical Properties of Silicon Nanoparticles for Photovoltaic Applications

The optical properties of silicon nanodots embedded in a dielectric matrix are studied. A critical review of the existing literature is presented, with focus on the specificity of the compositional and structural characteristics of the involved material. The results are applied to the simulation of spectrophotometric measurements taken on thermally treated silicon rich oxide (SRO) grown by Plasma Enhanced Chemical Vapor Deposition. Our results include the determination of the optical properties of the SRO host matrix. Simulation of the R&T data indicate the precipitation of amorphous silicon clusters for annealing temperatures below 1000°C, and subsequent crystallization for higher temperatures. The dielectric function of silicon nanoparticles that form after annealing is observed to closely approach the literature data obtained for samples fabricated by thermal precipitation from a silicon implanted SiO2 matrix.