X-ray pole figure analysis of catalyst free InAs nanowires on Si substrate

- Catalyst free InAs nanowires were grown on Si (1 1 1) using molecular beam epitaxy.
- X-ray pole figure measurements on the nanowires were done in several orientations.
- Detailed structural analysis was carried out using the pole figures.
- A quantitative approach was used to analyze twin planes and directions.
- Phase purity assessed from pole figure measurement and reciprocal lattice mapping.

We present crystallographic analysis of InAs nanowires by X-ray pole figure measurements and reciprocal space mapping in this report. The InAs nanowires have been grown on Si (1 1 1) substrates by a catalyst free approach using molecular beam epitaxy technique. The pole figure measurement of InAs nanowires for (1 1 1) and (2 2 0) reflections reveals important details such as the nanowire crystal structure, orientation, presence of twin defects and the epitaxial relation of the nanowires with the substrate. Angular relationship between several set of twin planes in each pole figure reflection is analyzed and the twin direction in each case is determined using a quantitative approach. Possibility of presence of mixed zinc blende /wurtzite phases in the nanowires is explored from an analysis of pole figure measurement for the (3 1 1) and (1 0 −1 5) reflections and an asymmetric reciprocal space map (RSM) measurement.