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تسجيل مستخدم جديدSynthesis of a new ternary nitride semiconductor -- Zn$_2$VN$_3$: A combinatorial exploration of the Zn-V-N phase space
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Computationally guided high-throughput synthesis is used to explore the Zn-V-N phase space, resulting in the synthesis of a novel ternary nitride Zn$_2$VN$_3$. Following a combinatorial PVD screening, we isolate the phase and synthesize polycrystalline Zn$_2$VN$_3$ thin films on conventional borosilicate glass substrates. In addition, we demonstrate that cation-disordered, but phase-pure (002)-textured, Zn$_2$VN$_3$ thin films can be grown using epitaxial stabilization on {alpha}-Al2O3 (0001) substrates at remarkably low growth temperatures well below 200 {deg}C. The structural properties and phase composition of the Zn$_2$VN$_3$ films are studied in detail using XRD and (S)TEM techniques. The composition as well as chemical state of the constituent elements are studied using RBS/ERDA as well as XPS/HAXPES methods. These analyses reveal a stoichiometric material with no oxygen contamination, besides a thin surface oxide. We find that orthorhombic Zn$_2$VN$_3$ is a weakly-doped p-type semiconductor demonstrating broadband room-temperature photoluminescence spanning the range between 2 eV and 3 eV, consistent with the bandgap of similar magnitude predicted by density functional theory-based calculations. In addition, the electronic properties can be tuned over a wide range via isostructural alloying on the cation site, making this a promising material for optoelectronic applications.
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