Synthesis and analysis of titanium nitride/titanium oxynitride films using colliding plasma pulsed laser deposition techniques

Abstract

Titanium nitride/oxynitride thin films hold significant potential for use as transparent coatings and for creating functionalized surfaces. We have investigated the synthesis and analysis of titanium nitride/ titanium oxynitride thin films on quartz substrates using reactive colliding pulsed laser deposition (CPLD) technique. The major challenge in reactive pulsed laser deposition of titanium nitride/oxynitride is controlling the reactive incorporation of nitrogen and oxygen species in the titanium plasma, due to complex plasma plume dynamics. Here, we have systematically investigated the interaction and expansion of colliding titanium plasma plumes over a broad pressure range (10⁻⁵ mbar to 10 mbar) using 2D imaging. The 2D imaging reveals that expansion of the plasma plume is strongly influenced by background pressure. At low pressure colliding plasma plumes expand freely in forward direction. While higher pressure leads to plume confinement due to increased collisions between the plasma and ambient species. Based on this study, we performed colliding-plume PLD in ambient air to deposit TiN/oxynitride films. The characterization of deposited films using XRD and EDXA confirms the presence of titanium nitride/ oxynitride phases with nitrogen content of ≈5 wt% and significant oxygen arising from both substrate and oxide formation. Optical transmittance measurements show the high transmittance (∼90%) in the range 400 nm-700 nm, consistent with non-uniform distribution of titanium nitride particulates and presence of titanium oxynitride.