Cross-scale structures fabrication via hybrid lithography for nanolevel positioning.

Planar cross-scale structures encode position and posture, enabling nanometer-level accuracy and multi-scale cascaded precision, emerging as a potential sensing device for semiconductor manufacturing and inspection systems. However, the fabrication of cross-scale hybrid structures, which is the integration of structures spanning three orders of magnitude in feature dimensions (500 nm-1.5 mm) on single substrates, still faces challenges. This requires fabrication of submicron-periodic encoder arrays (reflective regions) and micron-scale non-periodic absolute code tracks (transmissive regions) while maintaining directional consistency. Herein, we demonstrate a mask-interference hybrid lithography method to generate cross-scale structures. The multi-step lithography process integrates interference lithography for fabricating subwavelength periodic structures and mask lithography for patterning millimeter and micrometer-scale non-periodic structures. Alignment marks etched on the mask enable direction consistency between structural zones. The transmissive and reflective structures are differentially processed through region-specific etching and deposition. The effectiveness of this process in realizing the fabrication of hybrid structures is validated through experimental characterization. Moreover, the inherent process scalability establishes a versatile platform for creating multifunctional photonic architectures.