[16p-K204-1~5] (Open Symposium) Collaboration of acoustics and applied physics

2:30 PM - 2:45 PM JST(5:30 AM - 5:45 AM UTC)

[16p-K204-3] [The 57th Young Scientist Presentation Award Speech] A method for evaluating mechanical quality factor Q_m of ScAlN, ZnO, GaN piezoelectric film and metal films by using GHz ultrasonic pulse echo technique

〇Yohkoh Shimano^1,2, Takahiko Yanagitani^1,2 (1.Waseda Univ., 2.ZAIKEN)

Keywords:

Q factor,BAW filter,ScAlN

This study proposes a method for evaluating the intrinsic mechanical quality factor Q_m of thin films. An ultrasonic transducer on a substrate is fabricated with a film specimen on the backside of the substrate. The attenuation constant is estimated by comparing the echo from the bottom of the substrate and the bottom of the film specimen. In this report, the dependence of the Q_m of ScAlN films on the Sc concentration, as well as other piezoelectric thin films such as GaN and ZnO, and various metal materials and amorphous films were investigated. The relationship between crystal orientation and Q_m was also investigated.