Remote light-driven micromachines fabricated by 200 nm microstereolithography

We have developed a high-speed two-photon microstereolithography system. The resolution of our system is improved from 200 nm to 140 nm by the optimization of exposure conditions. Freely movable microstructures such as micromanipulators and microgears were also made by use of this system. In our method, movable microstructures are fabricated by fast scanning of an ultrashort-pulsed near-infrared laser beam through the inside of a liquid photocurable polymer. Since the method does not require sacrificial etching processes normally used in major micromachining such as surface micromachining and LIGA process, the fabrication process of movable microstructures can be drastically simplified. In addition, the movable microstructures can be driven by means of laser-scanning micro manipulation, because the resultant microstructures are transparent to visible and near infrared light. In our experiments, micromechanisms such as a microgear and micromanipulators were successfully driven by a focused laser beam. Apart from our method, there are no methods to produce and drive real 3D movable micromachines by light. Such light-driven micro-mechanisms should be developed into various microdevices applicable to microfluidics, chemistry and biochemistry.