Glass micromachining using the VUVF2 laser

Theoretical and experimental studies of the surface quality in 157nm F-2 laser-ablated glasses are reported. Limitations set by statistical fluctuations in the multi-mode beam and by stationary beam non-uniformity are explored together with materials issues such as laser- induced surface cracking. Experimental work on ablating polymethylmethacrylate (PMMA), used as a low threshold medium for recording of the VUV beam, and soda lime glass are described. Use is made of the probe beam deflection technique to determine ablation thresholds, and a variety of methods adopted for characterising and assessing the quality of ablated surfaces e.g. scanning-electron microscopy, mechanical and optical interference profiling and atomic force microscopy. Preliminary roughness measurements are compared with theoretical expectations and the implication for glass micromachining with the F-2 laser discussed.