Multiphoton lithographic approach for fabrication of planar-type MEMS

• Multiphoton lithography is applied to translate MEMS designs traditionally fabricated using silicon/wafer scale processes into 3D printed functional devices. • Chevron-type electrothermal actuators exhibiting an 2× magnitude larger current-induced deflection than silicon counterparts. • Demonstration of an integrated actuator–gear assembly that converts linear to rotational motion. • A preliminary evaluation of cyclic reliability highlighting observed fatigue trends and outlining future directions for improving durability. Microelectromechanical Systems (MEMS) are widely used in consumer electronics, automotive, and medical devices owing to their compact size, low power consumption, and seamless integration of mechanical and electrical functions. However, typical MEMS processes can be costly and take considerable time to carry out using conventional surface micromachining methods that can include over 100 steps. In this work, we evaluate the feasibility of 3D printing MEMS actuator components that resemble those fabricated using semiconductor/wafer scale approaches. Employing a multiphoton lithography (MPL) process, we design and print monolithically complex polymer structures that are subsequently coated with metal to allow electrification and device testing. Chevron-type printed actuators display significantly larger current-induced deflection versus similar silicon-based devices but suffer fatigue over thousands of cycles. Finally, we demonstrate an integrated electrothermal actuator and gear structure that converts linear to rotational motion. This work provides a foundational approach to enable a new era in rapidly prototyped, 3D MEMS devices.