Increase of electromechanical coupling coefficient kt2 in (0001)-oriented AlN films by chromium doping

• Published in: Japanese Journal of Applied Physics Vol. 60; no. SD
• Main Authors: Takano, Yusei, Hayakawa, Ryusei, Suzuki, Masashi, Kakio, Shoji
• Format: Journal Article
• Language: English
• Published: Tokyo Japanese Journal of Applied Physics 01.07.2021
• Subjects: Acoustic attenuation; Acoustic waves; Acoustics; Chromium; Coupling coefficients; Doping; Piezoelectricity; Resonators; Wave attenuation; Wave velocity

Piezoelectric AlN films possess high bulk acoustic wave velocity, low acoustic attenuation, and good temperature characteristics. However, AlN film bulk acoustic wave resonators (FBARs) have a relatively small electromechanical coupling coefficient k eff 2. It was recently reported that Cr doping in...