Design and Two-Photon Polymerization of Complex Functional Micro-Objects for Lab-on-a-Chip: Rotating Micro-Valves

Chung, Tien-Tung; Tseng, Chang-Li; Hung, Chia-Ping; Lin, Chih-Lang; Baldeck, Patrice L.
Two-Photon Polymerization is a powerful technology that can be used to fabricate complex functional micro-objects in lab-on-a-chip platforms. It is a laser-based prototyping technique with full tri-dimensional capability and sub-micron resolution. We report on the development of a computer-assisted design and fabrication process based on Q-switched Nd:YAG microlasers and AutoCAD environment. Microlasers with sub-nanosecond pulses of visible light are efficient and low cost lasers for two-photon microfabrication. Polymerization is easily obtained with sub-milliwatt average powers (12 kHz repetition rate). The microfabrication software has been developed to design the micro-object models and to calculate their laser trajectories using AutoCAD. It is open platform for the design of 3D solids with full access to entities information, and an efficient slicing command that can cut solids from any orientation plane. As a typical example of complex functional micro-object, we report on the fabrication of laser-driven rotating micro-valves. The design parameters have been optimized to allow a free movement of the valve around its axis using the optical force of a laser tweezers.
DOI