Light emission of silicon oxynitride films prepared by reactive sputtering of silicon

Silicon oxynitride (SiOxNy) films were prepared on silicon (Si) substrates by reactive sputtering of Si followed by vacuum annealing at 900 °C for 1 h. Structures and composition of the SiOxNy films were analyzed by x-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and transmission electron microscopy. The annealed SiOxNy films were amorphous and composed of mixed SiN and SiO bonds. Blue and green emissions were observed in the photoluminescence (PL) spectra of these annealed SiOxNy films. The intensity ratios of blue/green PL increased with the intensity ratios of the decomposed Si 2 p peaks corresponding to SiN and OSiN bonds. At last, electroluminescence (EL) was demonstrated in the SiOxNy/Si specimens with an indium-tin-oxide top electrode and an Al bottom electrode.