White bright luminescence at room temperature from TEOS-based thin films via catalytic chemical vapor deposition

Strong white luminescence, visible to naked eye at room temperature, was observed from as grown SiOxCy thin films without the need of annealing. SiOxCy thin films were prepared by using catalytic chemical vapor deposition method (Cat-CVD) employing TEOS solution as the precursor and bubbled with the argon gas to form vapors. TEOS vapors were catalytically decomposed in the deposition chamber with the help of a tungsten filament. Scanning electron microscope (SEM) and transmission electron microscope (TEM) confirmed the formation of nano-crystals in SiOxCy matrix. Inter-atomic spacing shows the transition of Si-SiC nano-crystals in matrix. The intense emission is believed to come up either from the carbon incorporation in the nanocrystalline-structured film and/or quantum confinement effect of the observed nano-crystals in SiOxCy matrix.