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摘要：
High-resolution electron-energy-loss spectroscopy (HREELS) showed that the dominant feature in the HREELS spectrum of the 'as-received' ITO was the loss peaks associated with the CH group. Oxygen-plasma treatment of ITO led to the disappearance of the CH loss peaks, and a concomitant increase in the intensity of the phonon peaks at 71 and 134 meV. The result indicates the removal of the CH group and additional oxidation of the ITO surface by the oxygen-plasma treatment. Both processes are proposed to be responsible for the increase in work function of ITO by the oxygen-plasma treatment. © 2003 Elsevier Science B.V. All rights reserved.
作者：
He P. 王穗东 Wong W. K. Cheng L. F. Lee C. 李述汤 Liu S. Y.
刊名：
Chemical Physics Letters
在线出版时间：
2003

摘要：
Boron nanowires have been synthesized by laser ablation at high temperature. The as-synthesized boron nanowires were characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and electron energy loss spectroscopy (EELS). The boron nanowires have lengths of several tens of micrometers long and diameters of 30-60 nm. The effects of the synthesis conditions on the formation of the boron nanowires were investigated and possible growth mechanisms of the boron nanowires are discussed. © 2003 Elsevier Science B.V. All rights reserved.
作者：
Meng 胡俊青 Yang Jiang Lee C. 李述汤
刊名：
Chemical Physics Letters
在线出版时间：
2003

摘要：
Small-diameter (1 to 7 nanometers) silicon nanowires (SiNWs) were prepared, and their surfaces were removed of oxide and terminated with hydrogen by a hydrofluoric acid dip. Scanning tunneling microscopy (STM) of these SiNWs, performed both in air and in ultrahigh vacuum, revealed atomically resolved images that can be interpreted as hydrogen-terminated Si (111)-(1 × 1) and Si (001)-(1 × 1) surfaces corresponding to SiH, on Si (111) and SiH, on Si (001), respectively. These hydrogen-terminated SiNW surfaces seem to be more oxidation-resistant than regular silicon wafer surfaces, because atomically resolved STM images of SiNWs were obtained in air after several days' exposure to the ambient environment. Scanning tunneling spectroscopy measurements were performed on the oxide-removed SiNWs and were used to evaluate the electronic energy gaps. The energy gaps were found to increase with decreasing SiNW diameter from 1.1 electron volts for 7 nanometers to 3.5 electron volts for 1.3 nanometers, in agreement with previous theoretical predictions.
作者：
Dorthy duo duo Ma Lee C. Frederick wing fai Au 唐叔贤 李述汤
刊名：
Science
在线出版时间：
2003

摘要：
The application of a cathode system comprising of an ultrathin CsF layer and an overlaid ytterbium (Yb) metal in organic electroluminescent devices is reported. This cathode shows dramatically reduced operating voltage and improved current and power efficiencies, both in small molecule or polymer based devices. The improvement is attributed to the dissociation of CsF upon Yb deposition to liberate low-work function Cs which reduces the electron injection barrier at the cathode/organic interface. Thermodynamically, the CsF dissociation is a substrate-independent process, and should be applicable for most organic based devices. Devices with this bilayer cathode system also show good operational stability. © 2003 Elsevier Science B.V. All rights reserved.
作者：
Mei yee Chan Shiulun Lai 冯敏强 Lee C. 李述汤
刊名：
Chemical Physics Letters
在线出版时间：
2003

摘要：
By introducing two methyl groups into 6 and 7 positions of the chromene group of a red fluorescent dye, 4-dicyanomethylene-2 (p-diphenylaminostyryl)-chromene (DCCPA), we have successfully synthesized a red organic materials, 4-dicyanomethylene-6,7-dimethyl-2 (p-diphenylaminostyryl)-chromene (DCCMPA) of considerably better florescence properties than DCCPA. Both photoluminescent (PL) and electroluminescent (EL) properties of DCCPA and DCCMPA have been examined and compared. The PL quantum yield of DCCMPA is 21% higher than that of DCCPA. The devices with DCCMPA doped into tris (8-quinolinolato) aluminum (Alq) also show higher efficiencies than the DCCPA doped devices. Based on these experimental results, some useful guidelines for molecular design of red organic materials for EL applications are discussed. © 2003 Elsevier Science B.V. All rights reserved.
作者：
Baijun Chen Xiaowei Sun Lin X. Q. Lee C. 李述汤
刊名：
Materials Science and Engineering B: Solid-State Materials for Advanced Technology
在线出版时间：
2003

摘要：
High quality epitaxial iridium films were grown on Si by using a fluoride as an intermediate layer. The epitaxial insulating layer acts as a diffusion barrier to impede film-substrate reactions at elevated temperatures and as a buffer layer for interface matching between lattice-mismatched metals and Si. Diamond deposited on the multilayer structure showed epitaxial growth. © 2003 Elsevier Science B.V. All rights reserved.
作者：
Lee C. H. Qi J. 李述汤 Liangsun Hung
刊名：
Diamond and Related Materials
在线出版时间：
2003