3D Microstructure Manufacture based on laser-induced thermoplastic expansion

In this paper, we describe a novel technology for three dimensional (3D) microstructure manufacture, which is based on the laser-induced thermoplastic expansion. A thermoplastic material melted by laser heating grows in the surrounding space filled with liquid, and after the laser irradiation is switched off, it immediately solidifies into a protuberant shape because of the heat release to the liquid surroundings. The size of 3D microstructure is controlled by the parameter of laser irradiation, including focal spot diameter, power density and irradiation time. This technology does not require expensive equipments or complicated steps, like molding, masking or bonding. We can fabricate microstructures swiftly, with a low cost. We have developed the experiment setup, which consists of laser, optical components and liquid container. And paraffin dots have been manufactured with this experiment setup.