Deposition of crystal polythiophene thin films by KrF excimer laser ablation

Thin films of polythiophene, a kind of polyheterocyclic compound with hydrogen function groups, were deposited by KrF excimer laser ablation of a compressed solid target in a vacuum chamber. The laser pulse fluence was approximately selected at 2 J/cm² with a pulse duration of 25 ns. The structural, topographic, and electronic properties of the deposited thin films were analyzed by atomic force microscope, x-ray diffraction, and Raman and infrared spectroscopy measurements. Deposited thin films were observed to have good crystal properties and to be composed of crystalline cubes with a uniform size of 0.1 μm. The electronic structure of the deposited thin films should be different from the target materials, resulting from the laser irradiation effects. The influence of the deposition temperature on the structural and electronic properties of the deposited thin films was studied.