U. Zeimer^a, V. Kueller^a, A. Knauer^a, A. Mogilatenko^a, M. Weyers^a, M. Kneissl^a,b

Published in:

J. Cryst. Growth, vol. 377, pp. 32-36 (2013).

Abstract:

The defect structure and the homogeneity of 1-3 µm thick Al_xGa_1-xN layers grown on epitaxially laterally overgrown (ELO) AlN on patterned AlN/sapphire templates have been investigated in dependence on the miscut direction of the c-plane sapphire substrates, the etching depth into the sapphire and the Al concentration. It was found that shallowly etched AlN/sapphire templates with a 0.25° miscut toward the a-plane provide a smooth surface of ELO AlN and therefore a good Al homogeneity in the overgrown Al_0.8Ga_0.2N layer. The threading dislocation density in these layers is as low as 5 × 10⁸ cm^-2.

Keywords:

A1. Characterization; A1. Defects; A3. Epitaxial lateral overgrowth; A3. Metalorganic chemical vapor deposition; B1. AlGaN; B3. Light emitting diodes.

© 2013 Elsevier B.V. All rights reserved. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the Elsevier B.V.

Full version in pdf-format.