Aluminum nitride based thin film bulk acoustic resonator using germanium sacrificial layer etching

Author

Hara, M. ; Kuypers, J. ; Abe, T. ; Esashi, M.

Author_Institution

Dept. of Mechatronics & Precision Eng., Tohoku Univ., Sendai, Japan

Volume

2

fYear

2003

Firstpage

1780

Abstract

We report the development of aluminum nitride (AlN) thin film bulk acoustic resonator (FBAR). This resonator has an air gap beneath the resonator to obtain high Q factor and low spurious response. Germanium (Ge) was used as a sacrificial layer for the air gap. This technique gives very simple process and high CMOS compatibility. The FBAR was evaluated about the effect of the air gap and the electrode size. The FBAR achieved a resonant frequency of 2 GHz, a Q factor of 780 and an effective electro-mechanical coupling constant (k/sub eff//sup 2/) of 5.36%.

Keywords

CMOS integrated circuits; III-V semiconductors; Q-factor; acoustic resonators; aluminium compounds; bulk acoustic wave devices; electromechanical effects; etching; semiconductor thin films; wide band gap semiconductors; 2 GHz; AlN-Ge; CMOS compatibility; Q factor; air gap; aluminum nitride; electrode; electromechanical coupling constant; film BAR; germanium sacrificial layer etching; thin film bulk acoustic resonator; Aluminum nitride; CMOS process; Electrodes; Etching; Film bulk acoustic resonators; Germanium; Piezoelectric films; Q factor; Substrates; Transistors;

fLanguage

English

Publisher

ieee

Conference_Titel

TRANSDUCERS, Solid-State Sensors, Actuators and Microsystems, 12th International Conference on, 2003

Conference_Location

Boston, MA, USA

Print_ISBN

0-7803-7731-1

Type

conf

DOI

10.1109/SENSOR.2003.1217131

Filename

1217131