| Autor: |
Ralph-Uwe Barz, T. Straubinger, Peter Gille, R. Radhakrishnan Sumathi |
| Rok vydání: |
2012 |
| Předmět: |
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| Zdroj: |
Journal of Crystal Growth. 360:193-196 |
| ISSN: |
0022-0248 |
| DOI: |
10.1016/j.jcrysgro.2011.11.054 |
| Popis: |
Bulk AlN single crystals (3 mm thick and 1 in. diameter) were hetero-epitaxially grown on (0001) 6H–SiC substrates by the sublimation method. Double-crystal x-ray diffraction and micro-Raman results confirm the good crystallinity as well as structural homogeneity of the grown crystals. The presence of low-angle grain boundaries was observed by x-ray diffraction rocking curve analysis and also supported by defect-selective etching analysis. The estimated defect density of the 3 mm thick crystals is about (5–8)×10 5 cm −2 . 3D-microstructures with different morphology were observed on the as-grown crystal surfaces and were interpreted to be originated from screw dislocations. These screw dislocations are decorated by carbon impurities as evidenced by micro-Raman spectroscopic measurements. SiC incorporation in the grown crystals was found to be fairly low with 4 mol% at 2 mm distance from the interface and varies slightly between different sub-grains. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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