title: Temperature-compensated aluminum nitride lamb wave resonators.
abstract: In this paper, the temperature compensation of AlN Lamb wave resonators using edge-type reflectors is theoretically studied and experimentally demonstrated. By adding a compensating layer of SiO2 with an appropriate thickness, a Lamb wave resonator based on a stack of AlN and SiO2 layers can achieve a zero first-order temperature coefficient of frequency (TCF). Using a composite membrane consisting of 1 microm AlN and 0.83 microm SiO2, a Lamb wave resonator operating at 711 MHz exhibits a first-order TCF of -0.31 ppm/degrees C and a second-order TCF of -22.3 ppb/degrees C(2) at room temperature. The temperature-dependent fractional frequency variation is less than 250 ppm over a wide temperature range from -55 degrees C to 125 degrees C. This temperature-compensated AlN Lamb wave resonator is promising for future applications including thermally stable oscillators, filters, and sensors.
authors.affiliation: Department of Mechanical Engineering, University of California, Berkeley, CA, USA. gimmylin@berkeley.edu
authors.forename: Chih-Ming
authors.initials: CM
authors.lastname: Lin
authors.forename: Ting-Ta
authors.initials: TT
authors.lastname: Yen
authors.forename: Yun-Ju
authors.initials: YJ
authors.lastname: Lai
authors.forename: Valery V
authors.initials: VV
authors.lastname: Felmetsger
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Hopcroft
authors.forename: Jan H
authors.initials: JH
authors.lastname: Kuypers
authors.forename: Albert P
authors.initials: AP
authors.lastname: Pisano