Laser ablated plasma plume characteristics for photocatalyst TiO2 thin films preparation

The TiO2 plasma plume produced by pulsed laser deposition (PLD) using a Nd:YAG laser (532 nm) is investigated by temporal and spatial resolved optical emission spectroscopy. Dynamics of neutral and ionized titanium species in the plume agreed with a drag model, which was explained as a collision between the excited species and ambient gas. The velocity of neutral oxygen atoms is constant in spite of increasing the delay time after the laser irradiation and the distance from the target. The crystallinity of TiO2 films deposited in the ablation plasma of Ti and TiN target was higher than that of TiO2 target.