Low-pressure-encapsulated resonant structures with integrated electrodes for electrostatic excitation and capacitive detection

摘要: Abstract Low-pressure-encapsulated resonant structures with lateral electrical feedthrough conductors for electrostatic excitation and capacitive detection are presented. The encapsulated device consists of a triple-stack wafer sandwich. middle is the silicon substrate structure. top bottom substrates micromachined Pyrex 7740 glass wafers metal electrodes. resulting pressure inside hermetically sealed cavity 1 mbar, obtained by low-pressure anodic bonding, starting from 10−5 without using any getter material or gas-evacuation procedure after bonding. A special electrode design presented, making it possible to have electrodes on both lids only standard fabrication steps. Low power consumption can be achieved voltages 5 10 Vr.m.s. sufficient excitation. long-term stability test low-pressure-encapsulated shows that storage one year (without integrated electrodes) three months (with no leakage has been observed. Finally, new technique investigated improve quality factor resonator. It anodically bonded frame structure as mask deep etching increase gap between wall resonator, thus yielding high Q-factor.