Linear acoustic bandgap arrays for spurious mode suppression in piezoelectric MEMS resonators

Author

Sorenson, Logan ; Fu, Jenna ; Ayazi, Farrokh

Author_Institution

Sch. of Electr. & Comput. Eng., Georgia Inst. of Technol., Atlanta, GA, USA

fYear

2011

fDate

2-5 May 2011

Firstpage

1

Lastpage

5

Abstract

In this work, we present a technique that utilizes arrays of coupled-ring linear acoustic bandgap (LAB) structures, which exhibit characteristic frequency stop bands, to reduce spurious modes in the wide-band response of AlN-on-Si lateral mode resonators. Aggressive LAB tethering (one support per finger) of high-order modes yields an increase in atmospheric quality factor (Q) from 1860 to 2890 for the designed peak at 209 MHz, compared to resonators with traditional tethers. Spurious modes from 0 to 360 MHz are suppressed by at least 30 dB relative to the main peak. The LAB structures presented achieve this goal through a combination of complete acoustic bandgaps and deaf bands.

Keywords

III-V semiconductors; acoustic arrays; aluminium compounds; crystal resonators; elemental semiconductors; micromechanical resonators; silicon; wide band gap semiconductors; AlN-Si; atmospheric quality factor; coupled-ring linear acoustic bandgap array; frequency 0 MHz to 360 MHz; piezoelectric MEMS resonators; spurious mode suppression; Acoustics; Couplings; Micromechanical devices; Oscillators; Photonic band gap; Resonant frequency; Shape;

fLanguage

English

Publisher

ieee

Conference_Titel

Frequency Control and the European Frequency and Time Forum (FCS), 2011 Joint Conference of the IEEE International

Conference_Location

San Fransisco, CA

ISSN

1075-6787

Print_ISBN

978-1-61284-111-3

Type

conf

DOI

10.1109/FCS.2011.5977862

Filename

5977862