RGC Senior Research Fellow Scheme

Biography

Professor in Department of Mechanical and Automation Engineering at The Chinese University of Hong Kong
Research in recent years focuses on the development of ultrafast laser-based microfabrication and micro-additive manufacturing processes
SRFS project — aims to address the major challenges in high-resolution photopolymerization processes, including resolution, throughput, cost, and reproducibility through two-photon lithography (TPL); and to enable large-scale applications of TPL and new functions such as optical part repair and modification for the first time. This project will develop a high-speed closed-loop projection-based TPL platform through the development of an optical diffraction tomography module to monitor the fabrication process in situ. Based on the new capabilities, this project will design, fabricate, and characterize large-scale optical and mechanical metamaterial structures and photonic devices with sub-50 nm resolution, generating significant impact in the nanomanufacturing and nanotechnology industry.
Awards and Honours:
- RGC Senior Research Fellow (2025)
- Bank of China (Hong Kong) Science and Technology Innovation Prize (Advanced Manufacturing) (2024)
- China’s Top 10 Optical Breakthroughs in 2023 Award (Fundamental Research) (2024)
- Winner of the Falling Walls 2023 "Science Breakthroughs of the Year" - Engineering & Technology (2023)
- R&D 100 Award for One of 100 Best New Technical Products of the Year - Digital Holography-based 3-D Nano-Builder (2018)

Project Title

Closed-loop High-throughput Super-resolution Two-photon Lithography

Award Citation

Professor Chen Shih-Chi is a Professor in the Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, who specializes in ultrafast laser applications and precision engineering. In this work, Professor Chen will address the long-standing challenges in nanoscale 3D printing, or two-photon lithography (TPL), and to enable large-scale applications of TPL and new functions, including optical part repair and modification for the first time.

TPL is an important additive manufacturing method that is typically performed via raster-scanning the focus of a femtosecond laser in photoresists, realizing a minimum feature size of ~150 nm. Yet, state-of-the-art commercial TPL systems have been plagued by their slow serial scanning process; and the use of TPL have been largely limited to academic research. For TPL to be used in practical applications, it is imperative to develop new methods that can simultaneously improve resolution, rate, and yield.

This project will first develop a high-speed closed-loop projection-based TPL platform through the development of an optical diffraction tomography (ODT) module to monitor the fabrication process in situ. The fast ODT system will realize pulse-by-pulse refractive index monitoring, precise laser dose control, and closed-loop TPL. To further enhance resolution without compromising speed, this project will combine the projection TPL with the concept of peripheral photo-inhibition, where up to 10,000 of periphery-confined laser foci (i.e., a super-resolved laser focus array with 50-nm resolution) are generated by superposing the projected laser foci with the photo-inhibition lattice pattern, realizing high-speed super-resolution TPL. Based on the new capabilities, this project will design, fabricate, and characterize large-scale optical and mechanical metamaterial structures and photonic devices with sub-50 nm resolution.

The new TPL platform will generate significant impact in the nanomanufacturing and nanotechnology industry. In addition, the ODT module may find wider applications in different photopolymerization processes and label-free 3D bio-imaging.