A Tip-Tilt-Piston Micromirror With an Elastomeric Universal Joint Fabricated via Micromasonry

A hybrid tip-tilt-piston micromirror driven by electrostatic actuation is presented in this letter. The micromirror involves a highly doped silicon mirror and a conductive elastomeric universal joint, which are mechanically bonded and electrically interconnected. This device takes advantage of two distinct materials to achieve a high-quality reflective surface using single-crystal silicon and a highly flexible universal joint using an elastomer. To realize this hybrid system, micromasonry techniques are employed such that silicon and elastomer parts are fabricated separately and integrated afterward. The static and dynamic behaviors of the micromirror are characterized, indicating identical response about its two orthogonal scanning axes. Furthermore, the piston stroke by the compressive deformation of the elastomeric joint along z-axis is investigated.