Strong blue and red luminescence in silicon nanoparticles based light emitting capacitors

Light emitting capacitors (LECs) were fabricated using silicon rich oxide (SRO) films as active layer. Blue and red electroluminescence (EL) was observed by changing the silicon nanoparticle (Si-np) size from 1.5 to 2.7 nm embedded in the silica matrix. EL is ascribed to the charge injection into the Si-nps embedded in the SRO films through a balanced transport network. The EL emission is observed with the naked eye and in daylight conditions on the whole area of devices. Therefore, these results prove the feasibility to obtain LECs by using simple capacitors with SRO films as the active layer. (C) 2011 American Institute of Physics. [doi:10.1063/1.3655997]