Temperature dependence of the light emission of Si nanocrystals embedded in SiO2

Abstract

Abstract We present results on the light emission of Si nanocrystals embedded into a SiO2 matrix obtained via ion implantation. As measurement temperature increases, the main photoluminescence peak shows a shift which is consistent with recombination involving confined electronic states of the nanoparticles around 150 – 170 K when the emission shows a sudden blueshift. After that, the usual energy redshift as temperature increases follows again. It was showed before that silicon nanoparticles light emission present a coexistence of localized states (surface or interface, that dominate the emission spectra at room temperature) and confined states (quantum confinement, dominating the low temperature range). In this work we investigate whether this anomaly in the nanoparticle PL peak energy as a function of temperature might be related to some of these localized states.