Reduction of dislocations in GaN epilayers using templated three-dimensional coherent nanoislands

Journal Article · Mon May 09 04:00:00 EDT 2005 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.1926419· OSTI ID:20702334

Jeganathan, K; Shimizu, M; Okumura, H ^[1]

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1. Power Electronics Research Center, National Institute of Advanced Industrial Science and Technology, Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)

Low-dislocation-density GaN layers have been grown on 6H-SiC(0001) substrates by molecular-beam epitaxy using high-density ({approx}4x10{sup 11} cm{sup -2}) self-assembled Stranski-Krastanov GaN nanoislands buffer. The density of dislocations determined from hot-wet chemical etching and atomic force microscopy show that the insertion of coherent nanoislands as a buffer reduces the defect migration from the interface to the GaN epitaxial layers. The dislocation density is dramatically dropped to {approx}10{sup 7} cm{sup -2} in GaN layers grown on coherent nanoislands as compared to {approx}10{sup 9} cm{sup -2} in the typical GaN layers grown on the AIN buffer.

• OSTI ID: 20702334
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 19 Vol. 86; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ATOMIC FORCE MICROSCOPY
CRYSTAL GROWTH
DISLOCATIONS
ETCHING
GALLIUM NITRIDES
LAYERS
MAGNETIC ISLANDS
MOLECULAR BEAM EPITAXY
SEMICONDUCTOR MATERIALS
SILICON CARBIDES
SUBSTRATES