Optical spectroscopy of plasma plume induced by pulsed laser deposition of TiO thin films

Kitazawa, Shinichi; Yamamoto, Shunya

The epitaxial growth of high quality TiO films has attracted much interest from the viewpoints of basic science and applications. In the synthesis process of TiO films, the pulsed laser deposition (PLD) method is widely employed because of its advantage for materials with high melting point. The laser irradiation generates plasmas from Ti bulk targets, and the evaporated Ti particles have interactions with buffer dioxide gas before/after the epitaxial growth. We observed the optical emission spectra from the plumes generated by laser ablation in order to improve on the epitaxial growth under proper conditions. The spectra show dependences of energy densities and wavelengths of the laser. The spectra are investigated for relevancies to the quality of films and crystallographic relationships that were assessed by x-ray diffraction, x-ray pole figures and Rutherford backscattering spectroscopy.