| Autor: |
Alekseev PA; Ioffe Institute , Saint Petersburg 194021 , Russia., Sharov VA; Ioffe Institute , Saint Petersburg 194021 , Russia.; Saint-Petersburg Academic University , Saint Petersburg 194021 , Russia., Dunaevskiy MS; Ioffe Institute , Saint Petersburg 194021 , Russia., Kirilenko DA; Ioffe Institute , Saint Petersburg 194021 , Russia., Ilkiv IV; Saint-Petersburg Academic University , Saint Petersburg 194021 , Russia., Reznik RR; ITMO University , Saint Petersburg 197101 , Russia., Cirlin GE; Saint-Petersburg Academic University , Saint Petersburg 194021 , Russia.; ITMO University , Saint Petersburg 197101 , Russia.; Saint Petersburg Electrotechnical University LETI , Saint Petersburg 197376 , Russia., Berkovits VL; Ioffe Institute , Saint Petersburg 194021 , Russia. |
| Abstrakt: |
The electronic properties of semiconductor AIIIBV nanowires (NWs) due to their high surface/volume ratio can be effectively controlled by NW strain and surface electronic states. We study the effect of applied tension on the conductivity of wurtzite In x Ga 1- x As ( x ∼ 0.8) NWs. Experimentally, conductive atomic force microscopy is used to measure the I - V curves of vertically standing NWs covered by native oxide. To apply tension, the microscope probe touching the NW side is shifted laterally to produce a tensile strain in the NW. The NW strain significantly increases the forward current in the measured I - V curves. When the strain reaches 4%, the I - V curve becomes almost linear, and the forward current increases by 3 orders of magnitude. In the latter case, the tensile strain is supposed to shift the conduction band minima below the Fermi level, whose position, in turn, is fixed by surface states. Consequently, the surface conductivity channel appears. The observed effects confirm that the excess surface arsenic is responsible for the Fermi level pinning at oxidized surfaces of III-As NWs. |
