Browsing by Author "Lee, T. C."

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Electrical measurements on iridium dioxide nanorods
(2006)
Lin, Y. H.
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Lee, T. C.
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Lin, J. J.
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Chang, H. M.
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Huang, Y. S.
Iridium dioxide (IrO2) nanorods have been prepared by metal-organic chemical vapor deposition method. Applying the standard electron-beam lithography technique, a single nanorod with a diameter of I 10 nm is contacted by three Cr/Au fingers from above. The resistance measurements on this nanorod have been performed between 10 and 300 K, using different probe configurations. We observe that the resistivity rho of the nanorod has a value <= 120 mu Omega cm at 300 K. On the other hand, the temperature dependence of the contact resistance R obeys the law logR proportional to T-1/2 below 100 K. The conduction process through the contact is ascribed to the transport of electrons via hopping in granular metals accidentally formed at the contact region.
Growth and optical properties of high-density InN nanodots
(2010-10-15)
Ke, W. C.
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Lee, S. J.
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Kao, C. Y.
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Chen, W. K.
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Chou, W. C.
High density InN/GaN nanodots were grown by pulsed mode (PM) metal-organic chemical vapor deposition (MOCVD). InN nanodots density of up to similar to 5 x 10(10) cm(-2) at a growth temperature of 550 degrees C was achieved. The high diffusion activation energy of 2.65 eV due to high NH(3) flow rate generated more reactive nitrogen adatoms on the growth surface, and is believed to be the main reason for the growth of high density InN nanodots. In addition, an anomalous temperature dependence of the PL peak energy was observed for high density InN nanodots. The high carrier concentration, due to high In vacancy (V(ln)) in the InN nanodots, thermally agitated to the conduction band. As the measurement temperature increased, the increase of Fermi energy resulted in blue-shifted PL peak energy. From the Arrhenius plot of integrated PL intensity, the thermal activation energy for the PM grown InN nanodots was estimated to be E(a)similar to 51 meV, indicating strong localization of carriers in the high density InN nanodots. (C) 2010 Elsevier B.V. All rights reserved.
Low-temperature electron dephasing time in AuPd revisited
(2007-10-01)
Lin, J. J.
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Lee, T. C.
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Wang, S. W.
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電子物理學系
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物理研究所
Ever since the first discoveries of the quantum-interference transport in mesoscopic systems, the electron dephasing times, T(P, in the concentrated AuPd alloys have been extensively measured. The samples were made from different sources with different compositions, prepared by different deposition methods, and various geometries (ID narrow wires, 2D thin films, and 3D thick films) were studied. Surprisingly, the low-temperature behavior of tau(phi) inferred by different groups over two decades reveals a systematic correlation with the level of disorder of the sample. At low temperatures, where tau(max)(phi) proportional to D-alpha is (nearly) independent of temperature, a scaling T-phi(max) proportional to D-alpha is found, where T-phi(max) is the maximum value of T-phi measured in the experiment, D is the electron diffusion constant, and the exponent alpha is close to or slightly larger than 1. We address this nontrivial scaling behavior and suggest that the most possible origin for this unusual dephasing is due to dynamical structure defects, while other theoretical explanations may not be totally ruled out. (c) 2007 Elsevier B.V. All rights reserved.
Observation of strong electron dephasing in highly disordered Cu93Ge4Au3 thin films
(2007-07-27)
Huang, S. M.
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Lee, T. C.
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Akimoto, H.
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Kono, K.
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Lin, J. J.
We report the observation of strong electron dephasing in a series of disordered Cu93Ge4Au3 thin films. A very short electron dephasing time possessing very weak temperature dependence around 6 K, followed by an upturn with further decrease in temperature below 4 K, is found. The upturn is progressively more pronounced in more disordered samples. Moreover, a lnT-dependent, but high-magnetic-field-insensitive, resistance rise persisting from above 10 K down to 30 mK is observed in the films. These results suggest a nonmagnetic dephasing process which is stronger than any known mechanism and may originate from the coupling of conduction electrons to dynamic defects.
Outsourcing in Business and Management Studies: A Co-Citation Analysis
(2017-01-01)
Yang, K. C.
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Yang, C.
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Huang, C. H.
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Lee, T. C.
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資訊管理與財務金融系註：原資管所+財金所
Outsourcing is a critical issue for an enterprise in the past two decades. It extended from the local operation service to the global service and influenced enterprise decision making process. Companies need to create competitive advantage from cost reduction, especially via outsourcing their operational activities. The purpose of this article is to bring up a visual mapping of two-dimensional intellectual structure and to recognize the subfields of the outsourcing through co-citation analysis. In this study, we collected some papers from ISI Web of Knowledge (WoS) database in the outsourcing area. We rank the outsourcing documents by times cited and collect the top 60 articles. Also, we use multidimensional scaling (MDS) and clustering techniques (CT) to create the two-dimensional maps to show the intellectual structure of outsourcing dynamically. The conclusion would provide for the researchers' reference.