Optical properties of GeO[SiO] and GeO[SiO2] solid alloy layers grown at low temperature

The optical properties of GeO[SiO] and GeO[SiO2] solid alloy films grown on Si(001) substrates were studied using Raman, Fourier transform infrared absorption (FTIR) and photoluminescence (PL) spectroscopies. A PL signal was observed in the infrared region both for as-deposited and annealed germanium silicate suboxide films. Furnace annealing led to an increase of the PL signal and to a redshift of the PL maximum. The PL at similar to 1100 nm is most probably due to defect-induced radiative transitions while the PL at similar to 1500 nm may be rather caused by amorphous Ge nanoclusters and Ge nanocrystals. Finally, the temperature dependence of the PL was studied. Anomalous quenching of the PL signal is observed which does not follow the classical Arrhenius law. The temperature dependence of the PL intensity is well explained by using a Berthelot model.

Automated summary

The optical properties of GeO[SiO] and GeO[SiO2] solid alloy films grown on Si(001) substrates were investigated, revealing that furnace annealing increases the photoluminescence (PL) signal and causes a redshift of the PL maximum. The temperature dependence of the PL showed anomalous quenching that could not be explained by the classical Arrhenius law. Instead, a Berthelot model provided a good explanation for the intensity of the PL signal.