The electrical and structural properties of n-type InAs nanowires grown frommetal–organic precursors

Abstract

The electrical and structural properties of⟨111⟩B-oriented InAs nanowires grown using metal–organic precursors have been studied.On the basis of electrical measurements it was found that the trends in carbonincorporation are similar to those observed in the layer growth, where an increasedAs/In precursor ratio and growth temperature result in a decrease in carbon-related impurities.Our results also show that the effect of non-intentional carbon doping is weakerin InAs nanowires compared to bulk, which may be explained by lower carbonincorporation in the nanowire core. We determine that differences in crystal quality, herequantified as the stacking fault density, are not the primary cause for variations inresistivity of the material studied. The effects of some n-dopant precursors (S, Se, Si,Sn) on InAs nanowire morphology, crystal structure and resistivity were alsoinvestigated. All precursors result in n-doped nanowires, but high precursor flowsof Si and Sn also lead to enhanced radial overgrowth. Use of the Se precursorincreases the stacking fault density in wurtzite nanowires, ultimately at high flowsleading to a zinc blende crystal structure with strong overgrowth and very lowresistivity.