AbstractWe have experimentally studied the photoluminescence (PL) properties of Si clusters in SiO2 glassy matrices. Si clusters in the SiO2 matrices were fabricated by Si+ ion implantation into SiO2 glasses and then thermally annealed in forming gas. Broad PL peaks are observed in the visible spectral region at room temperature. Resonantly excited PL spectra indicate that the strong coupling of excitons and stretching vibrations of the Si-0 bonds causes the broad luminescent spectra. It is concluded that the interaction between electronic and vibrational excitations controls the luminescent emission and the observed dynamics.
ABSTRACTSynthesis and size-dependent photoluminescence has been performed for Ge nanocrystals in SiO2 matrices with average diameters between 2 nm and 9 nm, formed by room temperature ion implantation into SiO2 followed by precipitation during vacuum thermal anneals. Nanocrystal size distributions obtained from electron microscopy data were used in conjunction with a quantum-confined exciton recombination model[l] to generate calculated photoluminescence spectra, which were compared with experimental spectra.
Large capacitance-voltage hysteresis loops in SiO2 films containing Ge nanocrystals produced by ion implantation and annealing