ZnO transparent thin films of different thickness were prepared with the Pulsed Laser Deposition (PLD) technique. The deposition of the films was carried out onto silicon and Corning glass substrates using a XeCl Excimer Laser (308 nm) as the light source and ZnO sintered ceramic targets in oxygen atmosphere. Structural investigations were carried out using Atomic Force Microscopy and X-ray Diffraction. As shown, the films grown have a polycrystalline wurtzite structure; the deposition parameters strongly affect the film surface topography (film roughness and shape/dimensions of grains) and the corresponding electrical/sensing properties. In addition, highly oriented nanostructures were identified, indicating the nucleation of nanorods with preferential orientation. The present work underlines that the film sensing properties can be controlled by modifying the deposition conditions.