Titanium-based films deposited using a Nd:YAG pulsed laser

Abstract.

Complex examinations were performed of the structure of films of metallic titanium, titanium nitride and titanium oxide deposited by means of PLD with a Nd:YAG laser. The influence of the deposition parameters on the film morphology was examined. The films revealed a nano-structure of good quality. A new tetragonal Ti(N) phase was revealed in the deposition of metallic titanium in a reactive chamber with an argon atmosphere. The TiN phase was formed during deposition of titanium nitride, independently of the nitrogen flow in the chamber. The transition of oxides from Ti₂O via TiO to TiO₂ was observed with an increasing flow of oxygen in the chamber for deposition of titanium oxide. TEM examinations of the microstructure in cross-sections of the film revealed a micro- columnar structure. All the examined films were characterised by a strong axial crystallographic preferred orientation on the basis of the measured pole figures. The <001> axial texture was identified within the deposited metallic titanium for the Ti(N) tetragonal phase as well as for the TiO oxide, while the <111> texture was observed in the case of TiN nitride. Measurements of the residual stresses of the first order in the TiN phase, by using the X-ray sin²ψ method, showed stress levels of -5000 to -7000 MPa. The residual stresses measured in the substrate of ferritic steel were about -150 MPa.