Photoluminescence properties of SiOxCy-films deposited under argon atmosphere and Si-based organometallic precursor by O-Cat-CVD

We report the deposition of silicon-based photoluminescent thin-films i.e. silicon oxycarbide (SiO
x
C
y
), with the help of organic catalytic chemical vapor deposition (O-Cat CVD) technique. Tetra-ethyl orthosilicate (TEOS) material was used as the single source organometallic precursor while tungsten (W) filament was exploited as catalyst during deposition. The deposition chamber worked under an atmosphere of argon (Ar) gas while the deposition time was 30 minutes. In this work, the influence of the argon flow was evaluated on the photoluminescence (PL) properties of the thin films which was varied from 20–60 sccm. Different bonding states and chemical states of the deposited films were analyezed by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) techniques, respectively. Through FTIR and XPS measurements, the formation of SiO
x
C
y
thin films has been confirmed. The thickness of the films and the refractive index were investigated from an ellipsometer at constant wavelength (632.8 nm) with variable angle measurements. The intense PL emissions were observed in a wide spectra of visible region for as-deposited films. The possible origin of PL emissions can be either from the incorporation of different luminescence-related defect centers and/or quantum confinement effect in the SiO
x
C
y
matrix.