Functional properties of silicon nanocrystals in oxigen-rich amorphous matrices formed by laser irradiation of substoichiometric silicon oxides

Autor: Alfredo Rubino, G. Fameli, Fulvia Villani, Stefano Salvatori, M. Burchielli, Maria Cristina Rossi, C. Felici, Gennaro Conte
Přispěvatelé: M., Burchielli, Conte, Gennaro, G., Fameli, C., Felici, Rossi, Maria Cristina, A., Rubino, S., Salvatori, F., Villani
Jazyk: angličtina
Rok vydání: 2002
Předmět:
Popis: Silicon-based nanostructured thin films have been obtained through laser irradiation of amorphous silicon oxides. The optoelectronic properties of nanostructured films largely differ from their amorphous counterpart, exhibiting optical gap narrowing, wavelength-dependent spectral modification of the photoluminescence (PL) and conduction mechanism variations. In particular, following the hydrogen effusion and related defect density increase, a spectral red shift and PL intensity quenching is detected for λ exc =514.5 nm, whereas PL enhancement and spectral blue shift is observed at λ exc =632.8 nm. Different thermal activation regimes of conductivity are also detected by conductivity measurements. Such results are discussed in terms of microstructural changes from an hydrogenated amorphous network to a nanostructured two-phase material where wavelength-selective excitation of radiative recombination channels and temperature-dependent conductivity paths occurs.
Databáze: OpenAIRE