| Autor: |
Weyher, J. L., Tichelaar, F. D., Zandbergen, H. W., Macht, L., Hageman, P. R. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 12/15/2001, Vol. 90 Issue 12, p6105, 5p, 7 Black and White Photographs |
| Abstrakt: |
Photoelectrochemical (PEC) etching has been used to study defects in heteroepitaxial GaN layers. In Ga-polar layers PEC etching reveals only dislocations in the form of filamentary etch features (whiskers). Transmission electron microscopy (TEM) confirmed a one-to-one correspondence between the whiskers and straight threading dislocations, which are mainly of edge and mixed type. In N-polar layers, apart from dislocations, inversion domains (IDs) also give rise to the formation of more complex etch features that also have been confirmed by TEM. IDs of nanometer diameter result in formation of whiskers similar to the dislocation-related ones. However, when the diameter of IDs exceeds a critical size (about 100 nm), crater-like deep etch features are formed during PEC etching. Based on the mechanism of PEC etching of GaN in aqueous KOH solutions, it is argued that inversion domain boundaries are electrically active defects. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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