Fundamental-mode VHF/UHF minature acoustic resonators and filters on silicon

Abstract

Novel bulk acoustic-wave high-Q resonators and acoustically coupled resonator filters have been fabricated and operated at their fundamental half-wavelength mode in the 200-500-MHz frequency range. These structures are fabricated on thin ZnO/silicon diaphragms with dimensions small enough to be incorporated within integrated circuits. Resonator Q’s near 2600 at the fundamental mode have been obtained and strong inter-resonator acoustic coupling has been achieved yielding filters having insertion loss (untuned) as low as 5.5 dB.

Two-step reactive sputtering of piezoelectric AlN thin films

“…Piezoelectric aluminum nitride (AlN) thin films have received a lot of attention for applications to high-frequency (GHz) acoustic wave devices, especially thin film bulk acoustic resonator (FBAR), for the last two decades [1][2][3][4][5][6][7][8][9]. The simplest configuration of such an FBAR is an AlN thin film sandwiched between two metal electrodes.…”

Characteristics of single crystalline AlN films grown on Ru(0001) substrates

“…Film bulk acoustic resonators (FBARs) are promising candidates for this purpose because they have several conspicuous advantages over conventional filter devices, including low insertion loss, high-power operation, and high Q factor at high frequencies [1,2]. FBARs consist of a thin piezoelectric film sandwiched between metal electrodes.…”

Growth of highly c-axis-oriented aluminum nitride thin films on molybdenum electrodes using aluminum nitride interlayers

“…A film bulk acoustic resonator (FBAR) filter is well suited for mobile telecommunication systems operating at high frequencies from 0.5 to 10 GHz. The basic structure of a FBAR consists a thin piezoelectric film sandwiched between two electrodes [1,2]. The piezoelectric film electrically excites acoustic waves.…”