Mirror-tunable laser interference lithography system for wafer-scale patterning with flexible periodicity

We propose and experimentally demonstrate a compact and cost-effective mirror-tunable laser interference lithography system to generate submicron grating structures with flexible periodicity. This system also enables a large-area illumination coverage that is not limited by the mirror size. Proof-of-concept demonstrations verify that this system is capable of generating 360-nm and 880-nm spaced gratings over a large 4-inch sample area without requiring optical path reconfiguration, thus is suitable for the realization of high-index-contrast grating mirrors used for a wide wavelength range.