Laser Interference Lithography for Fabrication of Planar Scale Gratings for Optical Metrology

Abstract Laser interference lithography is an attractive method for the fabrication of a large-area two-dimensional planar scale grating, which can be employed as multi-axis optical encoders or diffractive element in many types sensors. Especially, configurations such Lloyd’s mirror interferometer based on division wavefront generate fringe fields patterning grating pattern structures at single exposure stable manner. For to used planar/surface encoder, orthogonal two-axis interferometer, has been realized through innovation developed. In addition, concept structure extended non-orthogonal interferometer. Furthermore, setup optimized grating. this review article, principles generating are reviewed, while focusing encoders. Verification pitch fabricated structures, whose accuracy strongly affects performance encoders, also important task addressed. paper, major methods evaluation reviewed.