Optimized dose modulation for controlled greyscale electron beam lithography for negative tone resist

This study presents a systematic approach to optimizing dose modulation for precise greyscale electron beam lithography (EBL) using the negative tone resist AZ nLOF 2070. By establishing a correlation between local exposure dose and post-development resist height via the Rodbard equation, we generate dose distribution maps to guide the fabrication of complex micro-scale structures. A flood dose strategy is introduced to address underexposure in low-dose regions, significantly enhancing structural fidelity. Fabrication accuracy is quantitatively assessed through mean squared error (MSE) analysis, demonstrating high reproducibility across multiple samples and runs. Finally, the applicability of the method to nanoimprint lithography (NIL) is explored, highlighting its potential for scalable and precise greyscale patterning. • GS-EBL using negative AZ nLOF 2070 for reproducible free-form features. • Optimized dose strategy enhances shape fidelity control. • Resist profiles etched to Si and replicated by NIL for scalable fabrication.