INTEGRATED SHIELDING LINES ON MULTILAYER POLYSILICON RESONATORS

In this paper, multilayer polysilicon-silicon nitride beam resonators with integrated conductor and resistor patterns for driving and sensin g are presented. In particular, the resonators contain ground lanes be tween the active signal lines for reducing electrical crosstalk - a ma jor problem in two-port devices. The free-standing polysilicon structu res have been fabricated using an improved localized oxidation of sili con (LOCOS) process for the sacrificial oxide, which requires no addit ional mask. Several different resonator designs are proposed, always u sing piezoresistive detection while the excitation is either thermal o r capacitive. Preliminary frequency-response measurements of thermally excited resonators show promising characteristics; furthermore, the m easurements point out the importance of shielding.