3D Sub-Diffraction Printing by Multicolor Photoinhibition Lithography: From Optics to Chemistry

Photoinhibition lithography (PIL) is a nanoscale fabrication technique that uses multicolor visible light to enable the printing of arbitrary 3D structures beyond the diffraction limit. Photoinhibition allows the control and confinement of the exposed region for photoinitiation during the photolithographic process, thus improving the resolution of existing lithographic techniques, such as direct laser writing. Because PIL enables super-resolution 3D printing, it has a multitude of applications. In this review, practical applications of PIL in the areas of photonics, data storage, and biotechnology are highlighted; in addition, its unique features are revealed. The theory and recent advances in PIL for sub-diffraction printing and high-throughput fabrication are also discussed. Besides, challenges and tentative solutions are discussed with the hope of providing a preliminary roadmap for technological breakthroughs in PIL to enable developments of resolution and throughput.