Comparative Studies of Novel Capacitive Transducers with Non-Planar Diaphragms

Novel single-chip fabricated condenser structures with corrugated diaphragms for residual stress releasing have been proposed and simulated. An electrostatic-structural coupling FEM analysis has been performed to fully reveal the nonlinear relationship of output electrical signal with respect to input mechanical change. The influence of various nonlinear effects on the performance of transducers is investigated. Two typical corrugation layouts are studied. Numerical results have shown that the round structure was promising with its potential of high sensitivity, while the squared one was superior in the lowvoltage applications. The ill effects of these variations can be reduced by delicate design and adjusting of corresponding processes.