CNR ExploRA

Articolo in rivista, 2011, ENG, 10.1002/pssc.201000413

Optical properties of silicon rich oxides

Summonte C, Centurioni E, Canino M, Allegrezza M, Desalvo A, Terrasi A, Mirabella S, Di Stefano MA, Miritello M, Lo Savio R, Simonte F, Agosta R

CNR-IMM, Via Gobetti 101, 40129 Bologna, Italy Dip. di Fisica e Astronomia, CNR-IMM-Matis, Università di Catania, Via Santa Sofia 64, 95123 Catania, Italy IMS R and D, STMicroelectronics, Stradale Primosole 50, 95121 Catania, Italy

Thermally treated silicon rich oxides (SRO) used as starting material for the fabrication of silicon nanodots represent the basis of tunable bandgap nanostructured materials for optoelectronic and photonic applications. The optical modelization of such materials is of great interest, as it allows the simulation of reflectance and transmittance (R&T) spectra, which is a powerful non destructive tool in the determination of phase modifications (clustering, precipitation of new phases, crystallization) upon thermal treatments. In this paper, we study the optical properties of a variety of as-deposited and furnace annealed SRO materials. The different phases are treated by means of the effective medium approximation. Upon annealing at low temperature, R&T spectra show the precipitation of amorphous silicon nanoparticles, while the crystallization occurring at temperatures higher than 1000 °C is also clearly identified, in agreement with structural results. The existing literature on the optical properties of the silicon nanocrystals is reviewed, with attention on the specificity of the compositional and structural characteristics of the involved material.

Physica status solidi. C, Current topics in solid state physics (Internet) 8 (3), pp. 996–1001