| 1. |
- Jacobsson, Daniel, et al.
(författare)
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Particle-assisted GaxIn1-xP nanowire growth for designed bandgap structures
- 2012
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Ingår i: Nanotechnology. - : IOP Publishing. - 0957-4484 .- 1361-6528. ; 23:24
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Tidskriftsartikel (refereegranskat)abstract
- Non-tapered vertically straight GaxIn1-xP nanowires were grown in a compositional range from Ga0.2In0.8P to pure GaP in particle-assisted mode by controlling the trimethylindium, trimethylgallium and hydrogen chloride flows in metal-organic vapor phase epitaxy. X-ray energy dispersive spectroscopy in transmission electron microscopy revealed homogeneous radial material composition in single nanowires, whereas variations in the material composition were found along the nanowires. High-resolution x-ray diffraction indicates a variation of the material composition on the order of about 19% measuring an entire sample area, i.e., including edge effects during growth. The non-capped nanowires emit room temperature photoluminescence strongly in the energy range of 1.43-2.16 eV, correlated with the bandgap expected from the material composition.
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| 2. |
- Kriegner, D., et al.
(författare)
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Structural investigation of GaInP nanowires using X-ray diffraction
- 2013
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Ingår i: Thin Solid Films. - : Elsevier BV. - 0040-6090. ; 543, s. 100-105
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Tidskriftsartikel (refereegranskat)abstract
- In this work the structure of ternary GaxIn1-xP nanowires is investigated with respect to the chemical composition and homogeneity. The nanowires were grown by metal-organic vapor-phase epitaxy. For the investigation of ensemble fluctuations on several lateral length scales, X-ray diffraction reciprocal space maps have been analyzed. The data reveal a complicated varying materials composition across the sample and in the nanowires on the order of 20%. The use of modern synchrotron sources, where beam-sizes in the order of several 10 mu m are available, enables us to investigate compositional gradients along the sample by recording diffraction patterns at different positions. In addition, compositional variations were found also within single nanowires in X-ray energy dispersive spectroscopy measurements. (C) 2013 Elsevier B.V. All rights reserved.
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| 3. |
- Kriegner, D., et al.
(författare)
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Unit cell parameters of wurtzite InP nanowires determined by x-ray diffraction
- 2011
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Ingår i: Nanotechnology. - : IOP Publishing. - 0957-4484 .- 1361-6528. ; 22:42
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Tidskriftsartikel (refereegranskat)abstract
- High resolution x-ray diffraction is used to study the structural properties of the wurtzite polytype of InP nanowires. Wurtzite InP nanowires are grown by metal-organic vapor phase epitaxy using S-doping. From the evaluation of the Bragg peak position we determine the lattice parameters of the wurtzite InP nanowires. The unit cell dimensions are found to differ from the ones expected from geometric conversion of the cubic bulk InP lattice constant. The atomic distances along the c direction are increased whereas the atomic spacing in the a direction is reduced in comparison to the corresponding distances in the zinc-blende phase. Using core/shell nanowires with a thin core and thick nominally intrinsic shells we are able to determine the lattice parameters of wurtzite InP with a negligible influence of the S-doping due to the much larger volume in the shell. The determined material properties will enable the ab initio calculation of electronic and optical properties of wurtzite InP nanowires.
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