Browsing by Author "Li, TJ"

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Effect of annealing on electron dephasing in three-dimensional polycrystalline metals
(2002-03-01)
Lin, JJ
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Zhong, YL
;
Li, TJ
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電子物理學系
;
物理研究所
We have studied the effect of thermal annealing on electron dephasing times in three-dimensional polycrystalline metals. Measurements are performed on as-sputtered and annealed AuPd and Sb thick films, using the weak-localization method. In all samples, we find that possesses an extremely weak temperature dependence as T --> 0. Our results show that the effect of annealing is non-universal, and it depends strongly on the amount of disorder quenched in the microstructures during deposition. The observed saturation behavior of cannot be easily explained by magnetic scattering. We suggest that the issue of saturation can be better addressed in three-dimensional, rather than lower-dimensional, structures.
Electron-phonon scattering times in three-dimensional disordered Sb films
(2000-02-01)
Lin, JJ
;
Li, TJ
;
Wu, TM
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電子物理學系
;
物理研究所
We have measured the electron-phonon scattering times t(ep) in a series of three-dimensional Sb films having the characteristic of ql similar to 1, where q is the wave number of the thermal phonons, and I is the electron elastic mean free path. We observe that 1/t(ep) similar to T-p, With P approximate to 2.4, in the temperature range 1-14 K. In addition, we find a very weak dependence of 1/t(ep) on l. Our observations are compared with theoretical predictions for electronphonon interactions in the presence of disorder and with previous experimental results in thin Sb films.
Mg-related deep levels in AlInP
(1999-07-01)
Wu, YR
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Sung, WJ
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Lee, SC
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Li, TJ
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Lee, WI
The properties of deep levels found in Mg-doped AlInP, grown by metal-organic chemical vapor deposition, have been studied. Two distinct levels, labeled E1 and E2, were observed, with the activation energy of 0.19 and 0.514 eV, respectively. From distribution profiles measured on trap E1, E2 and Mg-dopant, all three concentration profiles have similar behaviors. The concentration increases gradually from the interface of pn junction. Furthermore, both trap E1 and E2 concentration increase with elevating Mg-dopant concentration Thus, it seems that these deep levels originate from Mg-related defects.
Phosphorus vacancy as a deep level in AlInP layers
(2000-06-15)
Sung, WJ
;
Wu, YR
;
Lee, SC
;
Wen, TC
;
Li, TJ
Deep levels in AlInP layers, grown by metal-organic chemical vapor deposition (MOCVD) with various V/III mole ratios, have been carefully investigated by deep-level transient spectroscopy (DLTS). A deep level originating from phosphorus vacancy was observed with the activation energy of 0.65 eV. Examining this phosphorus-vacancy-related deep level provided a relatively simple means of understanding the phosphorus vacancy in AlInP, thus allowing us to determine an appropriate V/III mole ratio for growing AlInP.