Piezoelectric characteristic of nanocrystalline AIN films obtained by pulsed laser deposition at room temperature

Abstract : Aluminum nitride AlN thin films were deposited at room temperature by pulsed laser deposition, and their nanostructure and piezoelectric properties were investigated as a function of fluence. For all fluences, the films were found to consist of an amorphous AlN matrix containing crystalline AlN nanoparticles with size of 6-7 nm. These nanoparticles spark off the good piezoelectric response, with d33 piezoelectric coefficients between 2.3 and 3.8 pm V−1, similar to those obtained for 002 -oriented AlN films deposited at higher temperatures. These results indicate that nanocrystalline AlN films deposited at room temperature are good candidates for integration in acoustic wave applications.