Ternary nitride semiconductors in the rocksalt crystal structure

Journal Article · 03 July 2019 · Proceedings of the National Academy of Sciences of the United States of America

DOI: https://doi.org/10.1073/pnas.1904926116 · OSTI ID:1564313

Bauers, Sage R.  ^[1]; Holder, Aaron  ^[2]; Sun, Wenhao ^[3]; Melamed, Celeste L. ^[4]; Woods-Robinson, Rachel ^[5]; Mangum, John ^[6]; Perkins, John ^[1]; Tumas, William ^[1]; Gorman, Brian ^[6]; Tamboli, Adele ^[1]; Ceder, Gerbrand ^[7]; Lany, Stephan ^[1]; Zakutayev, Andriy ^[1]

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1. Materials Science Center, National Renewable Energy Laboratory, Golden, CO 80401,
2. Materials Science Center, National Renewable Energy Laboratory, Golden, CO 80401,, Department of Chemical and Biological Engineering, University of Colorado, Boulder, Boulder, CO 80309,
3. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720,
4. Materials Science Center, National Renewable Energy Laboratory, Golden, CO 80401,, Department of Physics, Colorado School of Mines, Golden, CO 80401,
5. Materials Science Center, National Renewable Energy Laboratory, Golden, CO 80401,, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720,, Applied Science and Technology Graduate Group, University of California, Berkeley, CA 94720,
6. Department of Metallurgical and Materials Engineering, Colorado School of Mines, Golden, CO 80401,
7. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720,, Department of Materials Science and Engineering, University of California, Berkeley, CA 94720

Inorganic nitrides with wurtzite crystal structures are well-known semiconductors used in optical and electronic devices. In contrast, rocksalt-structured nitrides are known for their superconducting and refractory properties. Breaking this dichotomy, here we report ternary nitride semiconductors with rocksalt crystal structures, remarkable electronic properties, and the general chemical formula Mg _x TM _1−x N ( TM = Ti, Zr, Hf, Nb). Our experiments show that these materials form over a broad metal composition range, and that Mg-rich compositions are nondegenerate semiconductors with visible-range optical absorption onsets (1.8 to 2.1 eV) and up to 100 cm ² V ⁻¹ ⋅s ⁻¹ electron mobility for MgZrN ₂ grown on MgO substrates. Complementary ab initio calculations reveal that these materials have disorder-tunable optical absorption, large dielectric constants, and electronic bandgaps that are relatively insensitive to disorder. These ternary Mg _x TM _1−x N semiconductors are also structurally compatible both with binary TM N superconductors and main-group nitride semiconductors along certain crystallographic orientations. Overall, these results highlight Mg _x TM _1−x N as a class of materials combining the semiconducting properties of main-group wurtzite nitrides and rocksalt structure of superconducting transition-metal nitrides.

• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC36-08GO28308
• OSTI ID: 1564313
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Issue: 30 Vol. 116; ISSN 0027-8424
• Publisher: Proceedings of the National Academy of SciencesCopyright Statement
• Country of Publication: United States
• Language: English