| Autor: |
Motayed, Abhishek, Davydov, Albert V., Mohammad, S. N., Melngailis, John |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; Jul2008, Vol. 104 Issue 2, p024302, 5p, 1 Diagram, 1 Chart, 3 Graphs |
| Abstrakt: |
We report transport properties of gallium nitride (GaN) nanowires grown using direct reaction of ammonia and gallium vapor. Reliable devices, such as four-terminal resistivity measuring structures and field-effect transistors, were realized by dielectrophoretically aligning the nanowires on an oxidized silicon substrate and subsequently applying standard microfabrication techniques. Room-temperature resistivity in the range of (1.0–6.2)×10-2 Ω cm was obtained for the nanowires with diameters ranging from 200 to 90 nm. Temperature-dependent resistivity and mobility measurements indicated the possible sources for the n-type conductivity and high background charge carrier concentration in these nanowires. Specific contact resistance in the range of 5.0×10-5 Ω cm2 was extracted for Ti/Al/Ti/Au metal contacts to GaN nanowires. Significant reduction in the activation energy of the dopants at low temperatures (<200 K) was observed in the temperature-dependent resistivity measurement of these nanowires, which is linked to the onset of degeneracy. Temperature-dependent field-effect mobility measurements indicated that the ionized impurity scattering is the dominant mechanism in these nanowires at all temperatures. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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