Abstract: Pointing to the problem that it is hard for traditional machining methods to manufacture the parts of micro electromechanical systems(MEMS) with high quality, the method that standard involute micro gear is fabricated by polymerization fabrication technique of two-photon of femtosecond laser is provided based on the research of micro fabrication techniques. Fabrication system of two-photon of femtosecond laser is set up by using Ti-sapphire laser. Femtosecond laser whose wavelength is 800 nm may be output by the system for two-photon polymerization fabrication. Standard involute micro gear is designed with AutoCAD software. The relationship between laser power and the size of single voxel, the relationship between scanning step and the fabrication precision, surface roughness are researched through theory analysis and experiment. The results indicate that the machining resolution is higher when the laser power is smaller. When the scanning step is too smaller, the deformation is bigger, but the surface roughness is better. High quality standard involute micro gear with surface roughness Ra27.66 nm is fabricated with optimized fabrication parameters. Therefore, the fabrication technique of two-photon of femtosecond laser provides an effective way for fabrication of micro gear or the other MEMS parts.

Key words: Femtosecond laser, Micro gear, Microfabrication, Two-photon