Highly Sensitive Cationic Photoresist for High-Throughput Two-Photon Nanofabrication

Two-photon lithography (TPL) is a powerful tool for 3D nanofabrication, however, high-throughput TPL remains challenging, especially for cationic-based photoresists. A novel cationic-based photoresist named TP-EO is developed for high-throughput and high-resolution TPL nanofabrication. High-speed fabrication is achieved by using a bimolecular photosensitizer-photo acid generator (PS-PAG) pair that can effectively solve the photosensitivity bottleneck in cationic-based photoresists. High-resolution nanofabrication is achieved by limiting the photoacid diffusion via tuning the monomer's intra- and inter-molecular stereo-structure. The fabrication of 3D structures is demonstrated with fine features (<200 nm), fast writing speed (100 mm s(-1)), and low shrinkage, and showcased the rapid fabrication of centimeter-scale nanodevices. TP-EO photoresist shows outstanding TPL fabrication speed and resolution among cationic-based photoresists, making it a promising solution for high-throughput 3D nanomanufacturing.