Abstract
Atomic force microscopy, micro-Raman scattering and Auger spectroscopy were applied to study stress and material composition in Al0.34Ga0.66N grown by MOCHA on sapphire. Samples were annealed in N-2, O-2 and air ambient between 800 degreesC and 1200 degreesC. Annealing at temperatures above 800 C led to composition changes, cracks and defect formation resulting in stress release. Additionally, a change of built-in stress from tensile to compressive was observed after air annealing. Auger spectroscopy analysis showed this switching of stress to be related to oxygen incorporation. Oxygen accumulates in areas of macroscopic cracks as well as microscopic defects. Oxygen diffusion in AlxGa1-xN was found to be largely enhanced in the presence of water vapor in oxygen ambient. Samples were thermally stable up to 1100 degreesC in nitrogen and oxygen. Annealing in air led to a large surface oxidation.
Translated title of the contribution | High temperature annealing of AlGaN: Stress and composition changes |
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Original language | English |
Title of host publication | Int. Workshop on Nitride Semiconductors (IWN 2002) Aachen, Germany July 2002 |
Editors | Hoffmann , A A; Rizzi |
Publisher | Wiley-VCH Verlag |
Pages | 568 - 571 |
Number of pages | 4 |
ISBN (Print) | 3527404341 |
Publication status | Published - 2002 |
Bibliographical note
Conference Proceedings/Title of Journal: Int. Workshop on Nitride Semiconductors (IWN 2002) ProceedingsConference Organiser: Res Ctr Julich
Structured keywords
- CDTR