Interference lithography processes with high-power laser pulses

Laser interference lithography (LIL) is concerned with the use of interference patterns generated from two or several coherent beams of laser radiation for the structuring of materials. This paper presents the work on the processes based on resists and direct writing with laser interference lithography. In the work, a four-beam laser interference system was used as a submicrometer structuring tool in which a high-energy pulsed, frequency-tripled and TM polarized Nd:YAG laser (355 nm) with a coherent length of 3 m, energy power up to 320 mJ/cm2, pulse duration of 8 ns and 10 Hz repetition rate was used as a light source. The experimental results were achieved with 2-beam and 4-beam interference patterning. The processes can be used to define submicron surface relieves in large areas for use in the field of MEMS.