Chih-Yuan Wu

Electrical conduction processes in ZnO in a wide temperature range 20–500 K

We have investigated the electrical conduction processes in as-grown and thermally cycled ZnO single crystal as well as as-grown ZnO polycrystalline films over the wide temperature range 20–500 K. In the case of ZnO single crystal between 110 and 500 K, two types of thermal activation conduction processes are observed. This is explained in terms of the existence of both shallow donors and intermediately deep donors that are consecutively excited to the conduction band as the temperature increases. By measuring the resistivity ρ(T) of a given single crystal after repeated thermal cycling in vacuum, we demonstrate that oxygen vacancies play an important role in governing the shallow donor concentrations but leave the activation energy (≈ 27±2 meV) largely intact. In the case of polycrystalline films, two types of thermal activation conduction processes are also observed between ~150 and 500 K. Below ~150 K, we found an additional conductionprocess due to the nearest-neighbor-hopping conduction mechanism, wh...

Electron dephasing in homogeneous and inhomogeneous indium tin oxide thin films

The electron dephasing processes in two-dimensional homogeneous and inhomogeneous indium tin oxide thin films have been investigated in a wide temperature range 0.3--90 K. We found that the small-energy-transfer electron-electron (

Free-electronlike diffusive thermopower of indium tin oxide thin films

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Comment on 'Electron?phonon scattering in Sn-doped In2O3 FET nanowires probed by temperature-dependent measurements'

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Direct observation of structure effect on ferromagnetism in Zn1-xCoxO nanowires

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Electron-phonon scattering times in crystalline disordered titanium alloys between 3 and 15 K

) scattering process dominated the dephasing from a few K to several tens K. At higher temperatures, a crossover to the large-energy-transfer

Electron-electron interaction and weak-localization effects in Ti-Al alloys

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Temperature dependence of resistance and thermopower of thin indium tin oxide films

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PHONON-INDUCED ELECTRON-ELECTRON INTERACTION IN DISORDERED SUPERCONDUCTORS

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ELECTRON-ELECTRON INTERACTION AND NORMAL-STATE TRANSPORT IN SUPERCONDUCTING TI-(SN,GE) ALLOYS

scattering process was observed. Below about 1--2 K, the dephasing time