Effects of Crystal Phase Mixing on the Electrical Properties of InAs Nanowires

Abstract

We report a systematic study of the relationship between crystal quality and electrical properties of InAs nanowires grown by MOVPE and MBE, with crystal structure varying from wurtzite to zinc blende. We find that mixtures of these phases can exhibit up to 2 orders of magnitude higher resistivity than single-phase nanowires, with a temperature-activated transport mechanism. However, it is also found that defects in the form of stacking faults and twin planes do not significantly affect the resistivity. These findings are important for nanowire-based devices, where uncontrolled formation of particular polytype mixtures may lead to unacceptable device variability.

Internal field induced enhancement and effect of resonance in Raman scattering of InAs nanowires

“…There are quite a few reports in the literature, where the electronic band structure of the WZ phase of InAs has been calculated. 19,20,21,22 In a recent article, 11 it was shown that the band gap related resonant Raman intensity of the TO mode of the InAs NW down-shifts by 110 meV from that of the corresponding bulk material due to the decrease in E 1 gap of the WZ phase of the former. In the inset to Fig.…”

Electronic band structure of wurtzite GaP nanowires via temperature dependent resonance Raman spectroscopy

“…The dimensions of these wires are too large to exhibit electron/phonon confinement [1][2][3]. However, the modified crystal structure in such wires (in reference to corresponding bulk samples) indicates new possibilities in the realm of nanoscience and nanotechnology [4][5][6][7][8][9][10][11][12][13][14][15][16][17] It is now well established that NWs of III-V semiconductors can be grown in wurtzite (WZ) phase along their length, though the corresponding bulk materials are in zinc-blende (ZB) phase [5]. The indirect band gap in ZB phase [18] limits the application of the latter in optoelectronic device fabrication.…”

Surface modification-induced phase transformation of hexagonal close-packed gold square sheets

“…The functional properties of inorganic nanocrystals can be tuned by controlling their size, shape, composition and topology 3,4 . In addition, the crystal phase of inorganic nanomaterials can also strongly affect their properties, such as magnetic 5,6 , optical 7 , catalytic 8 and electrical properties 9 . For instance, the phase transformation of FePt nanoparticles from face-centered cubic (fcc) to face-centered tetragonal structures led to the improved catalytic activity and durability for the oxygen reduction reaction 8 .…”