The study of nickel-induced enhancement of near-infrared luminescence in Si-rich silicon oxide films

The mechanism of nickel-induced enhancement of photoluminescence (PL) in Si-rich SiO2 film has been investigated. Due to the increasing density of Si nanocrystals and decreasing decay rate of photoluminescence, the intensity of near-infrared emission from SiO1.56/Ni/Si samples was enhanced by a factor of 4 than that of SiO1.56/Si samples without the Ni interlayer after annealing at 1000 °C. Temperature-dependent PL spectra confirmed the quantum confinement effect as the origin of the luminescence transition in these two samples. The demonstration of light-emitting diodes based on SiO1.56/Ni/Si and SiO1.56/Si systems showed that the NiSi2-distribution in SiO1.56 film could improve the turn-on voltage and give an additional benefit to the electroluminescence efficiency.