Browsing by Issue Date, starting with "2009-05-07"

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Probing Capacitive Coupling and Collective Transport in PbSe Quantum-Dot Arrays Using Scanning Tunneling Spectroscopy
(2009-05-07)
Ou, Yi-Ching
;
Wu, Jiun-Ji
;
Fang, Jiye
;
Jian, Wen-Bin
;
電子物理學系
Semiconductor quantum dots with diameters of several to tens of nanometers have been largely synthesized through colloidal techniques for nanoscience exploration of quantum confinement, Coulomb staircase, and artificial-atom states in individual quantum dots and self-assembling growth behavior. Although charge transport of three-dimensional quantum dot arrays has been attempted for study on the micron scale, the electrical properties of a nanoscale array, self-assembled from a single quantum dot through a bottom-up procedure, have not been explored yet. We control growth parameters to self-assemble different sizes of PbSe quantum-dot arrays on flat gold surface for scanning tunneling spectroscopy measurements. The current-voltage curves of the arrays are analyzed using a double-barrier tunnel junction model to acquire the shunt capacitance between the array and the gold substrate. The increment of this capacitance is small as the particle number increases extremely from 1 to 40. Thus the array cannot be taken as a simple semiconductor island. We apply collective transport theory to exploration of electron tunneling and capacitive coupling between PbSe quantum dots in the array.
半導体基板上において３族窒化物半導体層を形成する方法
(2009-05-07)
張俊彦
;
楊宗▲き▼
;
沈詩國
【課題】シリコン半導体基板を含む半導体基板上において３族窒化物半導体層を大面積でエピタキシャル成長を行う技術を提供する。【解決手段】半導体基板の表面をフッ酸（ＨＦ）洗浄及び高温における酸化物の除去後、さらに３族窒化物ナノロッドバッファ層（ＧａＮナノロッドバッファ層）を形成し、３族窒化物半導体層（ＧａＮエピ層）を３族窒化物ナノロッドバッファ層において被覆成長させることで、半導体基板上に３族窒化物半導体層を形成する。【選択図】図２
UWB Gilbert downconverter utilising a wideband LR-CR quadrature generator
(2009-05-07)
Syu, J. -S.
;
Meng, C.
;
Teng, Y. -H.
;
電信工程研究所
;
Institute of Communications Engineering
An ultra-wideband (UWB) I/Q downconverter with an LR-CR quadrature generator is demonstrated using 0.35 mu m SiGe HBT technology. The I/Q outputs of this generator are always in quadrature phase at any frequency while the BJT-type active mixer inherently tolerates much LO power difference for a. at gain response. Consequently, the amplitude imbalance and phase error of the I/Q outputs are less than 1 dB and 2 degrees in the RF frequency range 3-11 GHz.
Infrared absorption of gaseous c-ClCOOH and t-ClCOOH recorded with a step-scan Fourier-transform spectrometer
(2009-05-07)
Chu, Li-Kang
;
Lee, Yuan-Pern
;
應用化學系
;
應用化學系分子科學碩博班
;
Department of Applied Chemistry
Two conformers of ClCOOH were produced upon irradiation at 355 nm of a gaseous flowing mixture of Cl(2), HCOOH, and N(2). A step-scan Fourier-transform infrared spectrometer coupled with a multipass absorption cell was utilized to monitor the transient spectra of ClCOOH. Absorption bands with origins at 1808.0 and 1328.5 cm(-1) are attributed to the C=O stretching and COH bending modes of t-ClCOOH, respectively; those at 1883.0 and 1284.9 cm(-1) are assigned as the C=O stretching and COH bending modes of c-ClCOOH, respectively. These observed vibrational wavenumbers agree with corresponding values for t-ClCOOH and c-ClCOOH predicted with B3LYP/aug-cc-pVTZ density-functional theory and the observed rotational contours agree satisfactorily with simulated bands based on predicted rotational parameters. The observed relative intensities indicate that t-ClCOOH is more stable than c-ClCOOH by similar to 3 kJ mol(-1). A simple kinetic model is employed to account for the production and decay of ClCOOH.
UV Absorption Cross Sections of ClOOCl Are Consistent with Ozone Degradation Models
(2009-05-08)
Chen, Hsueh-Ying
;
Lien, Chien-Yu
;
Lin, Wei-Yen
;
Lee, Yuan T.
;
Lin, Jim J.
Recently, discrepancies in laboratory measurements of chlorine peroxide (ClOOCl) absorption cross sections have cast doubt on the validity of current photochemical models for stratospheric ozone degradation. Whereas previous ClOOCl absorption measurements all suffered from uncertainties due to absorption by impurities, we demonstrate here a method that uses mass-selected detection to circumvent such interference. The cross sections of ClOOCl were determined at two critical wavelengths (351 and 308 nanometers). Our results are sufficient to resolve the controversial issue originating from the ClOOCl laboratory cross sections and suggest that the highest laboratory estimates for atmospheric photolysis rates of ClOOCl, which best explain the field measurements via current chemical models, are reasonable.
清華男排支柱王良瑋
(2009-05-10)
陳碩峰
;
Department of Communication and Technology
;
傳播與科技學系
訪問清大男排194
熱門偶像劇翻拍正夯
(2009-05-10)
鄭秀芳
;
Department of Communication and Technology
;
傳播與科技學系
0
總編的話
(2009-05-10)
郭大齊
;
Department of Communication and Technology
;
傳播與科技學系
總編的話
勾勒愛與妄想同人誌繪者
(2009-05-10)
楊睿愷
;
Department of Communication and Technology
;
傳播與科技學系
同人誌繪者
黃昏
(2009-05-10)
張雅晴
;
Department of Communication and Technology
;
傳播與科技學系
心情故事
If there is something...
(2009-05-10)
陳怡秀
;
Department of Communication and Technology
;
傳播與科技學系
不想休稿
甲型流感H1N1 旋風來襲
(2009-05-10)
林麗珊
;
Department of Communication and Technology
;
傳播與科技學系
甲型流感H1N1
外配找工作養家大不易
(2009-05-10)
林潔
;
Department of Communication and Technology
;
傳播與科技學系
1
《痞子英雄》　台灣戲劇的里程碑
(2009-05-10)
黃惠琳
;
Department of Communication and Technology
;
傳播與科技學系
好好看！
《十歲笛娜的願望》尋找幸福
(2009-05-10)
葉曉昀
;
Department of Communication and Technology
;
傳播與科技學系
影評
熱血醫師　新竹東門城開唱
(2009-05-10)
蔡尚翰
;
Department of Communication and Technology
;
傳播與科技學系
熱愛音樂醫師新竹東門城開唱
誰說，中國沒有動畫？
(2009-05-10)
陳妙寧
;
Department of Communication and Technology
;
傳播與科技學系
0
嘻哈音樂在台灣
(2009-05-10)
洪上筑
;
Department of Communication and Technology
;
傳播與科技學系
顆顆
跨領域合作增進求職優勢　
(2009-05-10)
吳佳玲
;
Department of Communication and Technology
;
傳播與科技學系
在金融海嘯的衝擊下，國內失業率飆升，許多人有感這年頭的工作是難保又難找。面對這樣的窘境，即將踏入社會的大學生也會面臨「畢業即失業」的問題嗎？為避免這樣的情況發生，大學生又該如何增加自己未來職場上的優勢呢？透過各領域的跨系合作，學生除了可以瞭解到其他不同領域的知識，還可以拓展視野，並提早瞭解到未來職場即將面臨的環境，跨系合作必然成為增加學生未來競爭力的新趨勢。
山寨機商機盜版與301名單
(2009-05-10)
邵奕儒
;
Department of Communication and Technology
;
傳播與科技學系
山寨機商機台恐返301名單