Vacancy defect distribution in heteroepitaxial a-plane GaN grown by hydride vapor phase epitaxy

• We have used positron annihilation spectroscopy to study the native vacancy distribution in a-plane heteroepitaxial GaN. We show that the Ga vacancy concentration is independent of the layer thickness in the range from 5 to 25 µ m. This is strikingly different from the behavior in c-plane GaN, where the Ga vacancy concentration decreases dramatically with the distance from the GaN/sapphire interface. This difference in the native vacancy profiles is tentatively correlated with the differences in the O impurity and dislocation density profiles in the polar and non-polar materials. © 2006 Elsevier B.V. All rights reserved.

Keyword

A1. Characterization

A1. Point defects

A3. Hydride vapor phase epitaxy

A3. Metalorganic chemical vapor deposition

B1. Nitrides

B2. Semiconducting gallium compounds

TECHNOLOGY

TEKNIKVETENSKAP

Publication and Content Type

ref (subject category)

art (subject category)