Abstract
The laser interference lithography (LIL) has two ways to fabricate the 2D periodic structures. The first method is multi-exposure LIL (2-beam LIL with double exposures), and the second method is multi-beam LIL (3-beam interference with single exposure). After simulation results, that research may have verified that multi-beam LIL has significantly better throughput than multi-exposure LIL. Therefore, this research design and develop a multi-beam LIL system. We integrate multiple theories, including those of optical interference, standing waves, and photoresist characteristics, to create a mathematical model for the LIL process. The mathematical model can accurately estimate the exposure time and reduce the LIL process duration through trial and error. In addition, LIL is very sensitive to the light source and the vibration. When there is a vibration source in the exposure environment, the standing wave distribution on the substrate will be affected by the vibration and move in a certain angle. As a result, Moiré fringe defects occur on the exposure result. In order to eliminate the effect of the vibration, we propose two methods for eliminating the vibrations from environment and improve the quality of the exposure process.