Surface micromachined GHz tunable capacitor with 14:1 continuous tuning range

This paper reports a new simply-supported bridge structure and its use for GHz tunable capacitor application. Unlike traditional MEMS bridges with fully-clamped boundary condition (B.C.) at the anchors, the new bridge structure has simply-supported B.C. Through the implementation of a simply-supported bridge driven by two 100-μm-long ZnO-actuated cantilevers, a compact surface-micromachined tunable capacitor has been fabricated on a single chip without any warping, and shown to be capable of a 1,400% continuous tuning from 0.13 pF to 1.82 pF.