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Accession Number:
ADA621907
Title:
Polarity Control and Growth of Lateral Polarity Structures in AlN
Descriptive Note:
Journal article
Corporate Author:
NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF MATERIALS SCIENCE AND ENGINEERING
Report Date:
2013-05-10
Pagination or Media Count:
7.0
Abstract:
The control of the polarity of metalorganic chemical vapor deposition grown AlN on sapphire is demonstrated. Al-polar and N-polar AlN is grown side-by-side yielding a lateral polarity structure. Scanning electron microscopy measurements reveal a smooth surface for the Al-polar and a relatively rough surface for the N-polar AlN domains. Transmission electron microscopy shows mixed edge-screw type dislocations with polarity-dependent dislocation bending. Raman spectroscopy reveals compressively strained Al-polar and relaxed N-polar domains. The near band edge luminescence consists of free and bound excitons which are broadened for the Al-polar AlN. Relaxation, better optical quality, and dislocation bending in the N-polar domains are explained by the columnar growth mode.
Distribution Statement:
APPROVED FOR PUBLIC RELEASE