EXCIMER-LASER PROCESSING FOR SURFACE IMPROVEMENT OF TIN OXIDE THIN-FILMS

Results are presented on the processing of tin oxide films using an ex cimer laser. Commercially available films of SnO2 deposited on glass s ubstrates were treated using a KrF excimer laser (248 nm). The results of these treatments were characterized by normal optical absorption, transmittance, and reflectance measurements in the VIS-NIR region alon g with x-ray diffraction and electrical conductivity measurements and a scanning electron microscopy (SEM) study. These were compared to the nontreated samples. The results inferred a relation between the amoun t of photoablated material with laser fluence, up to saturation. The o ptical spectroscopy results and the SEM study evidence modifications o f the treated surface. On the other hand, the x-ray analysis indicates that the crystal structure is not altered by the laser treatment but the film morphology is. Furthermore, an increase of 15% and better in the normalized integrated optical transmittance in the visible region was obtained with this treatment, without changing the film electrical conductivity.