Direct femtosecond laser lithography for photoresist patterning

Development of maskless lithography techniques may solve the problem of photomask cost. Furthermore, it could open a market for small-scale manufacturing applications. Since femtosecond lasers have been found suitable for processing of a wide range of materials with submicrometer resolution, it is attractive to use this technique for maskless lithography. In this paper, we report direct laser writing of lithographic patterns with submicron feature width on thin photoresist film by a femtosecond laser. The patterns were analyzed with a scanning electron microscope. The effects of laser energy and number of pulses on the feature size were investigated. Finally, we present various results on submicron photoresist patterning, which show great potential for future application.