Forskningsoutput per år
Forskningsoutput per år
Hanna Kindlund, Reza R. Zamani, Axel R. Persson, Sebastian Lehmann, L. Reine Wallenberg, Kimberly A. Dick
Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review
Using AlSb as the model system, we demonstrate that kinetic limitations can lead to the preferential growth of wurtzite (WZ) AlSb shells rather than the thermodynamically stable zinc-blende (ZB) AlSb and that the WZ and ZB relative thickness can be tuned by a careful control of the deposition parameters. We report selective heteroepitaxial radial growth of AlSb deposited by metal-organic vapor phase epitaxy (MOVPE) on InAs nanowire core templates with engineered lengths of axial WZ and ZB segments. AlSb shell thickness, crystal phase, nanostructure, and composition are investigated as a function of the shell growth temperature, Ts, using scanning electron microscopy, transmission electron microscopy, electron tomography, and energy-dispersive X-ray spectroscopy. We find that ZB- and WZ-structured AlSb shells grow heteroepitaxially around the ZB and WZ segments of the InAs core, respectively. Surprisingly, at 390 < Ts < 450 °C, the WZ-AlSb shells are thicker than the ZB-AlSb shells, and their thickness increases with decreasing Ts. In comparison, the ZB-AlSb shell thicknesses increase slightly with increasing Ts. We find that the increased thickness of the WZ-AlSb shells is due to the formation and enhanced deposition on {112-0} facets rather than on the more commonly grown {101-0} sidewall facets. Overall, these results, which are in direct contrast with previous reports suggesting that heteroepitaxial radial growth of III-antimonides is always favored on the ZB-structure facets, indicate that the growth of WZ-AlSb is preferred over the thermodynamically stable ZB-AlSb at lower growth temperatures. We attribute this behavior to kinetic limitations of MOVPE of AlSb on ZB and WZ phases of InAs.
Originalspråk | engelska |
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Sidor (från-till) | 5775-5781 |
Antal sidor | 7 |
Tidskrift | Nano Letters |
Volym | 18 |
Nummer | 9 |
DOI | |
Status | Published - 2018 |
Forskningsoutput: Avhandling › Doktorsavhandling (sammanläggning)