Micro-Masonry of MEMS Sensors and Actuators

Micro-masonry is a route to microassembly that involves elastomeric-stamp-based micromanipulation and direct bonding. This paper presents the assembly of MEMS mechanical sensors and actuators using micro-masonry, demonstrating its capability of constructing 3-D microdevices that are impossible or difficult to realize with monolithic microfabrication. Microfabrication processes for retrievable MEMS components (e.g., combs, spacers, and flexure beams) are developed. As micromanipulation tools, microtipped elastomeric stamps with reversible dry adhesion are also designed and fabricated to pick up and deterministically place those components. After the manipulation, the components are permanently bonded together via rapid thermal annealing without using any additional intermediate layers. The assembled MEMS device is modeled and analyzed in consideration of the microassembly misalignment. The sensing and actuating capabilities of the assembled MEMS devices are experimentally characterized.