Abstract
We demonstrate the nucleation of self-assembled, epitaxial GaN nanowires (NWs) on (111) single-crystalline diamond without using a catalyst or buffer layer. The NWs show an excellent crystalline quality of the wurtzite crystal structure with m-plane faceting, a low defect density, and axial growth along the c-axis with N-face polarity, as shown by aberration corrected annular bright-field scanning transmission electron microscopy. X-ray diffraction confirms single domain growth with an in-plane epitaxial relationship of (101̄0) GaN ∥ (011̄) Diamond as well as some biaxial tensile strain induced by thermal expansion mismatch. In photoluminescence, a strong and sharp excitonic emission reveals excellent optical properties superior to state-of-the-art GaN NWs on silicon substrates. In combination with the high-quality diamond/NW interface, confirmed by high-resolution transmission electron microscopy measurements, these results underline the potential of p-type diamond/n-type nitride heterojunctions for efficient UV optoelectronic devices. © 2012 American Chemical Society.
Original language | English |
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Pages (from-to) | 2199-2204 |
Journal | Nano Letters |
Volume | 12 |
Issue number | 5 |
DOIs | |
Publication status | Published - 9 May 2012 |
Keywords
- diamond
- GaN
- heteroepitaxy
- molecular beam epitaxy
- Nanowires
- nitrides