TY  - JOUR
AU  - Alagha, S.
AU  - Heedt, S.
AU  - Vakulov, Daniil
AU  - Mohammadbeigi, F.
AU  - Kumar, E Senthil
AU  - Schäpers, Thomas
AU  - Isheim, D.
AU  - Watkins, S. P.
AU  - Kavanagh, K. L.
TI  - Electrical properties of lightly Ga-doped ZnO nanowires
JO  - Semiconductor science and technology
VL  - 32
IS  - 12
SN  - 1361-6641
CY  - Bristol
PB  - IOP Publ.
M1  - FZJ-2017-08539
SP  - 125010 -
PY  - 2017
AB  - We investigated the growth, crystal structure, elemental composition and electrical transport characteristics of ZnO nanowires, a promising candidate for optoelectronic applications in the UV-range. Nominally-undoped and Ga-doped ZnO nanowires were grown by metal-organic chemical vapor deposition. Photoluminescence measurements confirmed the incorporation of Ga via donor-bound exciton emission. With atom-probe tomography we estimated an upper limit of the Ga impurity concentration (${10}^{18}\,{\mathrm{cm}}^{-3}$). We studied the electrical transport characteristics of these nanowires with a W-nanoprobe technique inside a scanning electron microscope and with lithographically-defined contacts allowing back-gated measurements. An increase in apparent resistivity by two orders of magnitude with decreasing radius was measured with both techniques with a much larger distribution width for the nanoprobe method. A drop in the effective carrier concentration and mobility was found with decreasing radius which can be attributed to carrier depletion and enhanced scattering due to surface states. Little evidence of a change in resistivity was observed with Ga doping, which indicates that the concentration of native or background dopants is higher than the Ga doping concentration.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000414194400003
DO  - DOI:10.1088/1361-6641/aa91ef
UR  - https://juser.fz-juelich.de/record/841495
ER  -