Theoretical and experimental analysis of an off-chip microgripper

This paper describes the design of a single-crystal-silicon off-chip electrothermal microgripper for use in micro-assembly and biological applications. Initially, a mechanical and thermal analysis is conducted with simulations of the gripper's operation using finite element software. The gripper is fabricated using silicon-on-insulator (SOI) technology and is then post-processed, assembled, and tested. The experimental and simulation results are compared, and, on average, the experimental gripper is found to require slightly less than half the power anticipated from the simulation results. The power needed to close the jaws the required 20 Am is determined experimentally to be approximately 33 mW, and the theoretical estimate of average chevron temperature change required to achieve this action is 165 K. The gripper is able to pick up and hold micro-sized objects that simulate biological cells.