Sputter deposition of stress controlled piezoelectric AlN and AlScN films for ultrasonic and energy harvesting applications

This paper will report on the deposition and characterization of piezoelectric AlN and Al_xSc_1-xN layers. A special focus is on the characterization regarding the mechanical stress in the films. Potential applications of the films are in ultrasonic microscopy, energy harvesting and SAW/BAW filters. To demonstrate the potential in ultrasonic applications, the pulse echo method was used.