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This content will become publicly available on February 6, 2026

Title: Realization of Non‐Equilibrium Wurtzite Structure in Heterovalent Ternary MgSiN 2 Film Grown by Reactive Sputtering
Abstract The piezoelectric and ferroelectric applications of heterovalent ternary materials are not well explored. Epitaxial MgSiN2films are grown at 600 °C on (111)Pt//(001)Al2O3substrates by the reactive sputtering method using metallic Mg and Si under the N2atmosphere. Detailed X‐ray diffraction measurements and transmission electron microscopy observations revealed that the epitaxially grown films on the substrates have a hexagonal wurtzite structure withc‐axis out‐of‐plane orientation. The random occupation of this structure by Mg and Si differs from that of the previously reported structure in which these two cations periodically occupy the cationic sites. However, the lattice spacings closely approximate those that are previously reported, irrespective of the ordering, and they are almost comparable with those of (Al0.8Sc0.2)N. The wide bandgap of >5.0 eV in deposited MgSiN2is compatible with that of AlN and suggests durability against the application of strong external electric fields, possibly to induce polarization switching. In addition, MgSiN2is shown to have piezoelectric properties with an effectived33value of 2.3 pm V−1for the first time. This work demonstrates the compositional expansion of hexagonal wurtzite to heterovalent ternary nitrides for novel piezoelectric materials, whose ferroelectricity is expected.  more » « less
Award ID(s):
2039351
PAR ID:
10584866
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley-VCH GmbH
Date Published:
Journal Name:
Advanced Electronic Materials
ISSN:
2199-160X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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