Ab-initio electronic structure calculations and properties of [SixSn1−x]3N4 ternary nitrides

• Published in: Thin solid films Vol. 613; pp. 43 - 47
• Main Authors: Pavloudis, Th, Zervos, M., Komninou, Ph, Kioseoglou, J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2016
• Subjects: [SixSn(1 − x)]3N4; Approximation; Band structure; Crystal structure; Density functional theory; Electronic structure; Energy bands; Energy gap; Mathematical analysis; Structure prediction; Thin films; Tin(IV) nitride; Structure prediction; Band structure; Density functional theory; Tin(IV) nitride; [SixSn(1−x)]3N4
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2015.09.072

We carry out ab initio electronic structure calculations of (SixSn1−x)3N4 using density functional theory with projector augmented-wave potentials under the generalized gradient approximation. We find that the energetically favorable structure of Sn3N4 is the face-centered cubic spinel structure, followed by the hexagonal structure which has energy band gaps of 1.85eV and 1.44eV respectively. The (SixSn1−x)3N4 ternary compound can exhibit both cubic and hexagonal crystal structures over the full range of x. However, the cubic structure is found to be energetically favorable for x<0.3 above which the hexagonal structure of (SixSn1−x)3N4 dominates. The energy band gap can be tuned continuously from 1.44eV up to 5.8eV in the case of the hexagonal crystal structure of (SixSn1−x)3N4 and from 1.85eV to 4.82eV in the case of cubic (SixSn1−x)3N4. Nevertheless the energy gap of (SixSn1−x)3N4 is direct only for x<0.3 when it is cubic and for x<0.5 when hexagonal. •(SixSn1−x)3N4 exhibits both cubic and hexagonal crystal structures.•The cubic structure is favorable for x<0.3 and the hexagonal structure for x>0.3.•The bandgap of hexagonal (SixSn1−x)3N4 may be tuned from 1.44eV up to 5.8eV.•The bandgap may be tuned from 1.85eV to 4.82eV for the cubic (SixSn1−x)3N4.•Bandgaps are direct for x<0.3 (cubic) and for x<0.5 3 (hexagonal (SixSn1−x)3N4).