Crystal Phase Transformation in Self-Assembled InAs Nanowire Junctions on Patterned Si Substrates

Abstract

We demonstrate the growth and structural characteristics of InAs nanowire junctions evidencing a transformation of the crystalline structure. The junctions are obtained without the use of catalyst particles. Morphological investigations of the junctions reveal three structures having an L-, T-, and X-shape. The formation mechanisms of these structures have been identified. The NW junctions reveal large sections of zinc blende crystal structure free of extended defects, despite the high stacking fault density obtained in individual InAs nanowires. This segment of zinc blende crystal structure in the junction is associated with a crystal phase transformation involving sets of Shockley partial dislocations; the transformation takes place solely in the crystal phase. A model is developed to demonstrate that only the zinc blende phase with the same orientation as the substrate can result in monocrystalline junctions. The suitability of the junctions to be used in nanoelectronic devices is confirmed by room-temperature electrical experiments.

Shadow-wall lithography of ballistic superconductor–semiconductor quantum devices

“…This method requires a subsequent etching step to expose gate-tunable wire segments without metal. Nanowires have also been grown on opposite crystal facets of etched trenches 11 , 26 , which enables the formation of shadowed junctions without the need to etch the superconductor 11 . The native oxide that forms during the ex-situ processing is removed prior to the deposition of the superconductor.…”

Shadow-wall lithography of ballistic superconductor-semiconductor quantum devices

“…This method requires a subsequent etching step to expose gate-tunable wire segments without metal. Nanowires have also been grown on opposite crystal facets of etched trenches [11,24], which enables the formation of shadowed junctions without the need to etch the superconductor [11].…”

Multiterminal Quantized Conductance in InSb Nanocrosses

“…We now consider the low-temperature electrical properties of the MBE-grown InSb NCs. Previous studies of InAs [27][28][29][30] and InSb NCs [17,21,31] have confirmed transport both along and between the two merged NWs, where both ballistic transport at high fields [31] and phase-coherence [21] have been demonstrated. A main reason for using branched nanostructures is the potential to individually gate control nanowire branches, thus enabling e.g.…”