Structural properties of SnO2 nanowires and the effect of donor like defects on its charge distribution
M
Zervos
author
A
Othonos
author
D
Tsokkou
author
J
Kioseoglou
author
E
Pavlidou
author
P
Komninou
author
2013
text
physica status solidi (a)
continuing
WILEY-VCH Verlag
periodical
academic journal
1862-6319
Tin oxide (SnO2) nanowires (NWs) with diameters of 50ânm, lengths up to 100âÂµm and a tetragonal rutile crystal structure have been grown by low pressure reactive vapour transport on 1ânm Au/Si(001). The free carrier density of the SnO2 NWs measured by THz absorption spectroscopy was found to be nâ=â(3.3âÂ±â0.4)âÃâ1016âcmâ3. Based on this we have determined the one-dimensional (1D) sub-band energies, overall charge distribution and band bending via the self-consistent solution of the PoissonâSchrödinger equations in cylindrical coordinates and in the effective mass approximation. We find that a high density of 1018â1019âcmâ3 donor-like defect related states is required to obtain a line density of 0.7âÃâ109 close to the measured value by taking the Fermi level to be situated â0.7âeV below the conduction band edge at the surface which gives a surface depletion shell thickness of 15ânm. We discuss the origin of the donor-like states that are energetically located in the upper half of the energy band gap as determined by ultrafast, time-resolved absorptionâtransmission spectroscopy.
defects, nanowires, spectroscopy, tin oxide
PSSA:PSSA201200403
10.1002/pssa.201200403
http://dx.doi.org/10.1002/pssa.201200403
2013
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