Patterning of Bi2O3 films using laser-induced forward and backward transfer techniques

Patterning of Bi2O3 films was performed by laser-induced forward transfer (LIFT) and backward transfer (LIBT) techniques using the SHG beam of a Nd:YAG pulsed laser. Patterned parallel tracks of the transferred film were obtained on glass sample plates with the 0.14-mm air gap by using these techniques. It was shown from the observation of the track pattern that the LIFT produced unclear track edges and nanoparticle/nanocluster of film material scattered on the glass plate, while the LIBT formed clear track edges and clear transferred surface. It was revealed that the skin depth effect was dominant on the laser irradiation from the estimation of skin depth of the incident laser and the thermal diffusion length of the Bi2O3 film. A vapor-driven propulsion of the film was presumed for the LIFT mode from this result, but for the LIBT mode, normal vaporization from uppermost film surface on laser irradiation was considered, which were confirmed by SEM observations and surface roughness calculation of AFM images for LIFT- and LIBT-transferred films. The results revealed the LIBT method was more adequate for the patterning of the Bi2O3 film compared with the LIFT method. (C) 2012 Elsevier B.V. All rights reserved.