A NEW FABRICATION PROCESS FOR MICROSTRUCTURES WITH HIGH AREA-TO-MASS RATIOS BY STIFFNESS ENHANCEMENT

摘要

A new fabrication process for stiffness-enhanced microstructures with high area-to-mass ratios is presented in this paper. In order to acquire an enhanced stiffness without ruining the structural parameter of area-to-mass ratio, multilayered metallic microstructures are proposed and fabricated by surface and bulk fabrication processes from Micro-Electro-Mechanical Systems (MEMS) technologies. Microstructures based on beams with symmetrically deposited metals are physically built and tested on wafers. A sacrificial silicon layer is used to form gaps between bimetal layers and the microstructures can be deployed vertically when heated due to the effect of thermal mismatch between different materials. The results show a dramatic thickness increase when actuated by Joule heating, and thus a great bending stiffness enhancement.