The effects of alloying and strain on the piezoelectric response of LaN-based material for the application in bulk acoustic wave resonator

• Published in: Materials today communications Vol. 46; p. 112650
• Main Authors: Xu, Chenhao, Wang, Zhen, Qian, Lirong, Zhou, Baozeng
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2025
• Subjects: Acoustic wave resonators; Electromechanical coupling coefficient; LaN-based alloy; Piezoelectric response; Uniaxial strain; Piezoelectric response; LaN-based alloy; Uniaxial strain; Electromechanical coupling coefficient; Acoustic wave resonators
• ISSN: 2352-4928; 2352-4928
• DOI: 10.1016/j.mtcomm.2025.112650

The interconversion between mechanical strain and electric polarization in piezoelectric materials has been the subject of extensive research. However, the symmetry breaking accompanied with lattice distortions plays an essential role in the piezoelectric properties, and needs to be further studied. In this work, utilizing first-principles method, an alloying model is constructed based on wurtzite-LaN (w-LaN) which has a large piezoelectric modulus (d33 = 21.45 pC/N) by incorporating group-Ⅲ elements X (X = B, Al, Ga, In), which has excellent piezoelectric behavior through systematic study of the mechanical properties of the system. The mechanical stability of all X0.5La0.5N alloys is satisfied by Born stability criterion except B-doped specimen. Particularly, in Al0.5La0.5N alloy, a largest piezoelectric modulus (d33 = 23.31 pC/N) is obtained due to the significant lattice distortion induced by the strain response of the internal coordinates with Al-doping. The influence of the relative concentration, occupancy of alloyed metal cations, and uniaxial strain on the piezoelectric response is further investigated. Moreover, a bulk acoustic wave resonator is constructed by using Al0.5La0.5N alloy, and the calculated results suggest that Al0.5La0.5N possesses a high electromechanical coupling coefficient and sound velocity, which is the great potential building block for bulk acoustic wave resonator. Our research provides critical insights for the design of bulk acoustic wave devices and the development of metal nitride piezoelectric materials. [Display omitted] •An alloying model is constructed based on wurtzite-LaN which has a large piezoelectric modulus.•In Al0.5La0.5N alloy, a largest piezoelectric modulus (d33 = 23.31 pC/N) is obtained due to the significant lattice distortion.•The influence of the relative concentration, occupancy of alloyed metal cations, and uniaxial strain on the piezoelectric response is further investigated.•A bulk acoustic wave resonator is constructed by using Al0.5La0.5N alloy.