Bimorph electrothermal micro-gripper with large deformation, precise and rapid response, and low operating voltage

Micro-grippers are highly desired in engineering, robotics, and biomedicine. However, on the basis of satisfying the requirements of miniaturization, precise manipulation, and low power consumption, the existing micro-grippers are difficult to achieve rapid response simultaneously. In this paper, we present a bimorph electrothermal micro-gripper that composed of several metal ultrathin films with high surface-to-volume ratios, allowing rapid heating and cooling processes. Patterns of these films are exquisitely designed so that the micro-gripper naturally forms an embedded circuit to optimize the current distribution. The micro-gripper can be precisely actuated under voltages below 2 V, while dramatically responding to pulse voltages up to 100 Hz. By interacting with a silica particle 96 times heavier than its weight, potential applications of the micro-gripper in robotics, organic tissue engineering, and interventional surgery can be shown. The advantage to be compatible with other semiconductor components ensures that the functions of the micro-gripper can be further expanded.