Design and integration of a bimorph thermal microactuator with electrostatically actuated microtweezers

A multi-digit gripper is proposed that consists of two electrostatically actuated end-effectors operating in the plane of the device and three thermal end-effectors operating out of plane. The integration of thermal and electrostatic actuation mechanisms is realized by using a three-mask monolithic process. First mask is used to define the silicon electrostatic actuator on SOI wafer. Second mask is used to obtain the bimorph thermal microactuator made of polyimide and aluminum layers on top of the electrostatic actuator. Third and the final mask is used to release the integrated electrostatic and thermal microactuators.