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.

Subject Categories:

  • Physical Chemistry
  • Electrooptical and Optoelectronic Devices
  • Crystallography
  • Solid State Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE