RECORDING GROOVES FOR FIBER-CHIP COUPLING IN PMMA USING KRF EXCIMER LASER RADIATION : EXPERIMENT AND SIMULATION

The fabrication of deep grooves with a high aspect ratio in poly-methylmethacrylate using excimer laser radiation (248 nm) and a cylindric lens has been investigated. The form of the grooves and their dimensions are evaluated with respect to the recording parameters. The patterns and their widths and depths may be adapted in a wide range depending on the particular application. As an example grooves for coupling monomode optical silica fibers were fabricated. Simulations were performed in order to explain the pattern formation. In a simple model the thermo-optic etching process may be simulated using a Gaussian-shaped laser beam and the FDBPM approach.