High speed ablation of glass using TEA-CO/sub 2/ laser

Laser ablation has been applied to synthetic quartz and BK-7 glasses using the TEA-CO/sub 2/ laser for maskless high speed etching. The TEA-CO/sub 2/ laser beam with a 10.6 /spl mu/m wavelength and 80 ns pulse duration was focused by a ZnSe lens down to a spot diameter of about 400 /spl mu/m on the sample surface. The repetition-rates of laser were varied from 1 pps to 1000 pps to investigate the dependence of ablation rate on the repetition rate. The ablation was performed at atmospheric pressure and in a vacuum of 4.2 x 10/sup -5/ Torr. Ablated profiles including depth and width are observed by a surface profiler and optical microscopy. The chemical compositions of the ablated bottoms were measured by electron probe microanalysis.