Fabrication of Soft Thermal Bimorph Microactuator Via Femtosecond Laser Surface Carbonization

This paper reports the fabrication method for a soft thermal bimorph microactuator via femtosecond laser surface carbonization. This method advances the application of thermal bimorph actuators in photothermal soft micro robotics. In this study, the surficial layer of a PDMS microcantilever, printed via micro-stereolithography, was carbonized through femtosecond laser irradiation, resulting in a bimorph microactuator with different thermal expansion coefficients. A fast response of 40 milliseconds and reproducible actuation were achieved through laser heating. Furthermore, the proposed fabrication method was applied to a 3D-printed insect-inspired microstructure, demonstrating its potential for soft microrobotics applications.