Nanoparticle-modified metal-oxide-silicon structure enhancing silicon band-edge electroluminescence to near-lasing action

With the insertion of SiO2 nanoparticles in the oxide layer, near-lasing actions such as threshold behavior and resonance modes are observed at the Si bandgap energy of metal-oxide-silicon (MOS) structure. The threshold current is similar to12 mA. The SiO2 nanoparticles cause simultaneous localization of electrons and holes to enhance phonon-assisted radiative recombination. Electroluminescence at Si bandgap energy is increased to orders of magnitude larger than in similar MOS structures without SiO2 nanoparticles. The efficient light emission at the Si bandgap energy indicates that a direct bandgap nature is not necessarily the basic requirement for radiative recombination. (C) 2002 Optical Society of America.