M. Fernández-Guasti

Structural characterization of TiO2 thin films obtained by pulsed laser deposition

The structural characterization by Raman spectroscopy and X-ray diffraction of TiO2 thin films obtained by pulsed laser deposition is reported. The substrate temperature and the oxygen pressure effects are investigated. The main result is that rutile TiO2 thin films are obtained at low substrate temperatures. The film growth occurred mainly in the (110) direction.

Micro-Raman characterization of WO3 and MoO3 thin films obtained by pulsed laser irradiation

Abstract Thin films of MoO3 and WO3 have been obtained by pulsed laser deposition. The structure of the films and of the splashed species were studied by Raman microscopy. In the case of WO3 a single monoclinic phase was observed. For MoO3 the deposited material corresponds to its metastable phase known as β-MoO3. In the splashed species a mixture of the α-MoO3 and β-MoO3 phases is found.

Spectroscopic studies of two perpendicularly interacting carbon plasmas generated by laser ablation

The interaction of two plasmas generated by laser ablation from two perpendicular carbon (graphite, 99.99% purity) targets was analyzed by optical emission spectroscopy. The 1064 nm line of a Nd:YAG laser was used as energy source. Spatial and temporal measurements were performed. The covered spectral range was from 280 to 740 nm. Time of flight measurements were performed to determine the kinetic energies of different excited species. It was found that the excited species were more energetic; however, their lifetimes were shorter when the two plasmas were interacting. Carbon thin films were deposited at different positions relative to the plasmas and subsequently characterized by scanning electron microscopy and Raman spectroscopy.

Raman characterization of Bi12SiO20 thin films obtained by pulsed laser deposition

The synthesis by pulsed laser deposition and characterization by Raman spectroscopy of Bi12SiO20 thin films are presented. The Raman spectra of the thin films are close to their crystalline counterpart only in the presence of an oxygen flow during growth. In the absence of oxygen, the observed spectra are similar to that of pure bismuth material.