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arXiv · 1509.08256

Layered transition metal dichalcogenides: promising near-lattice-matched substrates for GaN growth

Priti Gupta·A. A. Rahman·Shruti Subramanian·Shalini Gupta·Arumugam Thamizhavel·Tatyana Orlova·Sergei Rouvimov·Suresh Vishwanath·Vladimir Protasenko·Masihhur R. Laskar·Huili Grace Xing·Debdeep Jena·Arnab Bhattacharya
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Abstract

Most III-nitride semiconductors are grown on non-lattice-matched substrates like sapphire or silicon due to the extreme difficulty of obtaining a native GaN substrate. We show that several layered transition-metal dichalcogenides are closely lattice matched to GaN and report the growth of GaN on a range of such layered materials. We report detailed studies of the growth of GaN on mechanically-exfoliated flakes WS$_2$ and MoS$_2$ by metalorganic vapour phase epitaxy. Structural and optical characterization show that strain-free, single-crystal islands of GaN are obtained on the underlying chalcogenide flakes. We obtain strong near-band-edge emission from these layers, and analyse their temperature-dependent photoluminescence properties. We also report a proof-of-concept demonstration of large-area epitaxial growth of GaN on CVD MoS$_2$. Our results show that the transition-metal dichalcogenides can serve as novel near-lattice-matched substrates for nitride growth.

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Priti Gupta, A. A. Rahman, Shruti Subramanian, Shalini Gupta, Arumugam Thamizhavel, Tatyana Orlova, Sergei Rouvimov, Suresh Vishwanath, Vladimir Protasenko, Masihhur R. Laskar, Huili Grace Xing, Debdeep Jena, Arnab Bhattacharya. 2015-09-28. Layered transition metal dichalcogenides: promising near-lattice-matched substrates for GaN growth. https://doi.org/10.1038/srep23708

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