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The surface properties of some polymers in relation to physicochemical affinity to similar or other materials (adhesion, moistening, adsorption etc.) are very poor, which then limits their use in specific technical applications. To improve the surface properties in this field a mechanical, wet-chemical or plasma treatment of the work pieces is applied. Most of these methods, however, have some disadvantages as, for example, alteration of the surface morphology, poor controllability and pollution of the environment. These are the reasons why improvement of these technologies are the subject of current research. One relatively new way to change the surface conditions of polymers is the use of excimer lasers. Recent results are presented concerning the interaction of UV-laser radiation with polymers and resulting photolytical modification and activation (adhesion, morphology) of their surface. These results show that under certain conditions polar groups are observable. On the basis of such activati...

Laser-assisted chemical etching of Co, Cr, Cu and Ti w;is investigated using aqueous solutions of phosphoric acid and KOH at different concentrations. Thin metal films on glass substrates and thin foils were etched upon irradiation with a focussed Ar-laser operating at 514 nm and an output power of about 1 W. Static etch rates of the order of 10 pmμmsol;s were obtained at measured background etch rates less than 103 nm/s. The influence of the laser power on the etch rate suggests dominating thermally activated etch reactions. Due to the thermal nature of the etch process etched lines of about two times smaller width than the estimated laser spot diameter could be obtained. Etching of lines in thin Ti films on glass subsu'ates was performed by laser direct writing at speeds of about 1 mm/s and a laser power of about 0.3 W. Cutting of thin Ti foils was obtained at cutting velocities of about 30 um/s and a power of 0.8 W. The width of the etched lines was found to be controlled by laser power and wr...