Abstract Surface modification processes using various excimer UV sources are described. In addition to applications of excimer lasers, photolytic processes using newly developed incoherent excimer UV and vacuum UV sources are discussed. These UV sources, based on excimer formation in silent discharges, offer photolytic large area surface treatment at low temperature. Results are presented on the photoetching of polymer surfaces. In addition, metal deposition processes are discussed. In a two-step method, thin metal—organic films are used to obtain activated surface areas for subsequent electroless plating processes. The decomposition of thin solid films on arbitrary surfaces can be initiated by excimer lasers as well as by excimer lamps. It is concluded that laser irradiation involves pyrolytic decomposition effects while lamp exposure results mainly in photolytic decomposition of the precursor films. Direct activation of surfaces for electroless plating is demonstrated using high intensity excimer laser irradiation.