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In this paper, we review our main results on the optical and electrical properties of light-emitting silicon nanocrystals (Si-ncs) obtained from the thermally induced nucleation in amorphous silicon-rich nitride (SRN) films deposited either by plasma-enhanced chemical vapor deposition (PE-CVD) or magnetron sputtering. In particular, we discuss the Si-ncs microscopic light emission mechanism combining the optical data with the first-principle calculations of the absorption/emission Stokes shifts and recombination lifetimes. In addition, we report on the electrical injection characteristics of simple p-i-n device structures showing efficient bipolar transport and room temperature electroluminescence, and demonstrate efficient energy sensitization of erbium (Er) ions from the Si-ncs embedded in the SRN matrices. We further show that the light-emitting nanocrystals in SRN can be embedded in aperiodic photonic environments, where the localized optical modes can be used to significantly enhance the Si-ncs emission intensity at different emission wavelengths. These results suggest that the Si-ncs embedded in the SRN matrices have a large potential for the fabrication of optically active photonic devices based on the Si technology. [ABSTRACT FROM PUBLISHER]

We review our main experimental and theoretical results on the optical emission properties of Si-nanocrystals (Si-nc's) fabricated by colloidal and thin film deposition techniques, showing that the surface chemistry of the Si-nc's or the surrounding matrix play a crucial role in determining both the structural stability and the optoelectronic properties of Si-nc. Our results, guided by first-principles simulations indicate that nitrogen, oxygen, and carbon atoms bonded to the surface of nanometer silicon clusters play a crucial role in the emission mechanism of small Si quantum dots. The control and the understanding of the Si-nc surface structure and composition can provide alternative routes toward the fabrication of optically active complementary metal/oxide semiconductor devices. [ABSTRACT FROM PUBLISHER]