Laser photoablation processes in organosilane thin films

We report on the excimer laser-induced photoablation of some organosilane polymers utilizing quartz microbalance techniques to monitor the nature of the ablation phenomenon. A fluence threshold for the ablation process is identified beyond which the material removal rate depends nonlinearly on the adsorbed laser fluence. Below this threshold, photo-oxidation of the polymer is observed as evidenced by mass uptake of the film. Our results suggest that photoablation of the polysilanes studied is a result of a combination of thermal and photochemical processes.