Mishra, Monu and Gundimeda, Abhiram and Krishna, Shibin and Aggarwal, Neha and Gahtori, Bhasker and Dilawar, Nita and Aggarwal, Ved Varun and Singh, Manju and Rakshit, Rajib and Gupta, Govind (2017) Wet chemical etching induced stress relaxed nanostructures on polar & non-polar epitaxial GaN films. Physical Chemistry Chemical Physics, 9 (13). pp. 8787-8801. ISSN 1463-9076

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Abstract

We report formation of aligned nanostructures on epitaxially grown polar and nonpolar GaN films via wet chemical (hot H3PO4 and KOH) etching. The morphological evolution exhibited stress relaxed faceted nanopyramids, flat/trigonal nanorods and porous structures with high hydrophilicity and reduced wettability. The nanostructured films divulged significant suppression of defects and displayed an enhanced intensity ratio of the near band edge emission to the defect band. Extensive photoemission analysis revealed variation in oxidation state along with elimination of OH- and adsorbed H2O molecules from the chemically modified surfaces. Fermi level pinning, and alteration in the surface polarity with substantial changes in the electron affinities were also perceived. The temperature dependent currentvoltage analysis of the nanostructured surfaces displayed enhancement in current conduction. The in-depth analysis demonstrates that the chemically etched samples could potentially be utilized as templates in the design/growth of III-nitride based high performance devices.

Item Type:	Article
Additional Information:	Copyright for this article belongs to M/s Royal Society of Chemistry.
Subjects:	Chemistry > Physical Chemistry Physics > Atomic and Molecular Physics
Divisions:	UNSPECIFIED
Depositing User:	Users 27 not found.
Date Deposited:	31 May 2019 11:17
Last Modified:	31 May 2019 11:17
URI:	http://npl.csircentral.net/id/eprint/2934

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