Submicron-resolution ablation with a KrF excimer laser beam patterned with a projection lens

A mask projection system working with KrF laser radiation is described. This system produces microscopic laser beams able to pattern gratings on the surface of various materials in the micrometer range by direct etching. Models have been developed to simulate the beam intensity profile on the sample. Various polymers have been irradiated, and their experimental profiles are compared with theoretical ones. Different ablation behaviors have been evidenced. Interesting consequences of thermal effects at this submicron scale are reported.