Design Optimisation and fabrication of SU-8 based electro-thermal micro-grippers

This paper describes the design and simulation of an integrated micro-electro-mechanical system (MEMS) to be used for micromanipulation. Electrothermal micro-grippers were designed for micro-tensile tests of biological materials which require relatively low force and temperature. Finite element analysis (FEA) was performed to examine gripper opening displacements, tip temperature and stresses. The feasibility of various materials including silicon, plated nickel and SU-8 was examined for applications in biological environment. The paper looks at fabrication techniques employed to allow a cheaper, wet etching solution, to the fabrication of SU-8 micro-grippers. The structure was successfully fabricated and tested. The results showed that the micro-gripper could be actuated by fairly low voltage.