Reduction of the dislocation density in HVPE-grown GaN epi-layers by an in situ SiNx treatment
| Autor: | D.V. Sridhara Rao, Daniela Gogova, Roberto Fornari, Hina Ashraf, Colin J. Humphreys, P.R. Hageman, Dietmar Siche |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Applied Materials Science
Materials science business.industry Scanning electron microscope Nucleation Gallium nitride Condensed Matter Physics Epitaxy Amorphous solid Inorganic Chemistry Crystallography chemistry.chemical_compound chemistry Transmission electron microscopy Materials Chemistry Sapphire Optoelectronics Dislocation business |
| Zdroj: | Journal of Crystal Growth, 312, 595-600 Journal of Crystal Growth, 312, 4, pp. 595-600 |
| ISSN: | 0022-0248 |
| DOI: | 10.1016/j.jcrysgro.2009.11.043 |
| Popis: | A new method has been approached to reduce the dislocation density in hydride vapor phase epitaxy (HVPE)-grown GaN epi-layers. By this method, state of the art quality, GaN layers were grown on sapphire substrates with an in situ treatment of SiNx in HVPE process. It was found out that the in situ treatment worked most effectively when introduced after the deposition of the nucleation layer (NL). Amorphous SiNx served as a mask allowing only selective growth of GaN seeds as confirmed by scanning electron microscopy (SEM) analysis and thus a reduction of the dislocation density (down to 106 cm−2) with one order of magnitude lower compared to the standard samples (grown without the SiNx treatment) was obtained. Transmission electron microscopy (TEM) studies revealed that dislocations with a mixed (both screw and edge component) character mostly thread into the GaN layer. Low-temperature photoluminescence showed good optical quality of the layers grown with optimal position of SiNx treatment. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect