Pulsed laser irradiation of 3 mu m thick silicone films at 157 nm below and above the ablation threshold of about 100 mJ/cm(2) has been investigated. Significantly above the ablation threshold, clean material removal is observed. Irradiation below threshold leads to surface swelling and a modification of the chemical composition as revealed by Raman spectroscopy. After 10,000 pulses at 30 mJ/cm(2) a nearly carbon free silica like material is obtained. The 157 nm-ablation threshold of this modified material amounts to 800 mJ/cm(2), which is similar to that of fused silica. At 60 mJ/cm(2), the CH3-content is similarly reduced, but a graphitization is observed after about 10 000 pulses. In both cases the modified material exhibits broadband visible luminescence. Combinations of modification and ablation are used to fabricate patterned silica films. (C) 2012 Elsevier B.V. All rights reserved.