Polyimide surface modification by pulsed ultraviolet laser irradiation with low fluence

Abstract Surface modification on a polyimide film by pulsed ultraviolet (UV) laser irradiation with a fluence below its ablation threshold was studied by X‐ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and UV‐vis spectroscopy. It was observed that a photochemical reaction occurred and hydrophilic groups, such as —OH and —COOH, formed on the polyimide surface after irradiation. In addition, a ripple microstructure formed on the surface when the angle of incidence of the laser beam was 20–50 o . The contact angle of the polyimide surface with water decreased and the adsorption ability of the surface to a water‐soluble dye clearly increased after laser irradiation. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2739–2743, 2001