Browsing by Issue Date, starting with "2007-08-16"

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Coaxial transitions for CPW-to-CPW flip chip interconnects
(2007-08-16)
Wu, W. C.
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Chang, E. Y.
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Huang, C. H.
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Hsu, L. H.
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Starski, J. P.
A novel coaxial transition for CPW-to-CPW flip chip interconnect is presented and experimentally demonstrated. To realise the coaxial transition on the CPW circuit, benzocyclobutene was used as the interlayer dielectric between the vertical coaxial transition and the CPW circuit. The coaxial interconnect structure was successfully fabricated and RF characterised to 67 GHz. The structure showed excellent interconnect performance from DC up to 55 GHz with low return loss below 20 dB and low insertion loss less than 0.5 dB even when the underfill was applied to the structure.
Triazole-modified calix[4]crown as a novel fluorescent on-off switchable chemosensor
(2007-08-16)
Chang, Kai-Chi
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Su, In-Hao
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Senthilvelan, Annamalai
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Chung, Wen-Sheng
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應用化學系
A novel fluorescent on-off switchable chemosensor 1 with two different types of cationic binding sites is synthesized, which is composed of a triazole-modified calix[4]crown in the 1,3-alternate conformation. Among 15 metal ions examined, the fluorescence of 1 was strongly quenched by Hg2+, Cu2+, Cr3+, and Pb2+; however, the revival of emission from the strongly quenched 1 center dot Pb2+ complex was achievable by the addition of K+, Ba2+, or Zn2+ ions. Thus, metal ion exchange can trigger an on-off switchable fluorescent chemosensor.
Solar-pumped active device
(2007-08-16)
Chi, Sien
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Chen, Nan-Kuang
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Shy, Jow-Tsong
The present invention provides a solar-pumped active device which utilizes a holographic antenna grating on a solar energy silicon substrate to select specific diffracted wavelength and couple pump wavelength in an approximately vertical way and converge the pump wavelength to excite an optical gain medium so that an optical amplifier or a laser can be obtained. The present invention requires no big size and is flexible over the surface shape and is suitable for free space optical communications on the ground and satellite optical communications. It means that the holographic antenna grating can be applied on the top floor of a building or on the glass surface of an outer wall. If it is applied to a satellite, the present invention can be deposited on a solar energy cell substrate to form a high optical amplification so that not only the electricity required in satellite optical communications can be reduced, but also a high-speed and large capacity of data can be transferred between satellites.
Unique pitch evolution in the Smectic-C-alpha(*) phase
(2007-08-17)
Liu, Z. Q.
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McCoy, B. K.
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Wang, S. T.
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Pindak, R.
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Caliebe, W.
Employing resonant x-ray diffraction, we observed unique pitch evolutions in the smectic-C-alpha* phase in mixtures of two antiferroelectric liquid crystals. Our results show that the pitch in this phase continuously evolves across 4 layers, contradicting a theoretical model that predicts that the smectic-C-FI2* phase intervenes in the smectic-C-alpha* phase. The phase sequences we found can be explained by another model that includes one type of long-range interaction among smectic layers.
COLL 483-Fabrication of phosphated TiO2 through calcination of TOPO-capped nanocrystals
(2007-08-19)
Chang, Sue-min
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Hou, Chieh-yao
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環境工程研究所
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Institute of Environmental Engineering
ENVR 173-Photoactivity of TOPO-capped TiO2 nanocrystals toward the degradation of endocrine disrupting chemicals
(2007-08-19)
Chang, Sue-min
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Lo, Pin-han
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Hou, Chieh-Yao
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環境工程研究所
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Institute of Environmental Engineering
FUEL 241-Preparation of Palladium-membrane by electroplating on AISI 316 porous stainless steel supports and its use for methanol steam reformer
(2007-08-19)
Rei, Min Hon
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Chen, Shin Chung
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Tu, George Chia
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Hung, Chia Yeh
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材料科學與工程學系
COMP 105-Prediction of Raman spectra in novel polyyne@SWNT peapods using dispersion-augmented density-functional-tight-binding
(2007-08-19)
Irle, Stephan
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Witek, Henryk A.
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Shinohara, Hisanori
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Morokuma, Keiji
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應用化學系
COLL 272-Helical morphologies in the self-assembly of chiral Schiff-based rod-coil amphiphiles
(2007-08-19)
Lin, Tz-Feng
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Ho, Rong-Ming
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Sung, Chien-Hung
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Hsu, Chain-Shu
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應用化學系
ANYL 456-Fabrication of novel molecularly imprinted alumina-silica using non-hydrolytic sol-gel method for trace phosphine detection
(2007-08-19)
Chang, Sue-min
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Hou, Ching-jung
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Yen, Shao-Yi
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Li, Shou-Nan
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環境工程研究所
INOR 65-Effect of surface and lattice vanadium ions on the physicochemical and photocatalytic properties of porous TiO2
(2007-08-19)
Chang, Sue-min
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Liu, Wei-Szu
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Sung, Pin-Hsin
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環境工程研究所
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Institute of Environmental Engineering
Volume shrinkages and mechanical properties of various fiber-reinforced hydroxyethyl methacrylate-polyurethane/unsaturated polyester composites
(2007-08-19)
Lin, Shih-Pin
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Shen, Jia-Hong
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Han, Jin-Lin
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Lee, Ya-Rong
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Yeh, Jen-Taut
Nonvolatile memory characteristics of nickel-silicon-nitride nanocrystal
(2007-08-20)
Chen, Wei-Ren
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Chang, Ting-Chang
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Liu, Po-Tsun
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Yeh, Jui-Lung
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Tu, Chun-Hao
The formation of nickel-silicon-nitride nanocrystals by sputtering a comixed target in the argon and nitrogen environment is proposed in this letter. High resolution transmission electron microscope analysis clearly shows the nanocrystals embedded in the silicon nitride and x-ray photoelectron spectroscopy also shows the chemical material analysis of nanocrystals. The memory window of nickel-silicon-nitride nanocrystals enough to define 1 and 0 states is obviously observed, and a good data retention characteristic to get up to 10 years is exhibited for the nonvolatile memory application.
Sr3B2O6 : Ce3+,Eu2+: A potential single-phased white-emitting borate phosphor for ultraviolet light-emitting diodes
(2007-08-20)
Chang, Chun-Kuei
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Chen, Teng-Ming
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應用化學系
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Department of Applied Chemistry
The Ce3+/Eu2+ coactivated Sr3B2O6 phosphors exhibit varied hues from blue through white and eventually to yellow-orange by resonance-type energy transfer from Ce3+ to Eu2+ and tuning the relative proportion of Ce3+/Eu2+ properly. The authors have demonstrated that electric dipole-dipole interaction dominates the energy transfer mechanism in Sr3B2O6:Ce3+,Eu2+ phosphor, and the critical distance of energy transfer has been estimated to be about 30 A by both spectral overlap and concentration quenching methods. They have also shown that under the excitation of UV radiation, white light is generated by coupling 434 and 574 nm emission bands attributed to Ce3+ and Eu2+ radiations, respectively.
月亮洗頭
(2007-08-20)
管管
Micellization and the surface hydrophobicity of amphiphilic poly(vinylphenol)-block-polystyrene block copolymers
(2007-08-20)
Tung, Pao-Hsaing
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Kuo, Shiao-Wei
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Chan, Shih-Chien
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Hsu, Chih-Hao
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Wang, Chih-Feng
The self-assembly of PVPh-b-PS in different solvents was studied. Upon replacing toluene by THF as the solvent, the morphology of the resulting aggregates change from core-shell spheres, rod-like micelles and vesicles to onion-like aggregates. With increasing block copolymer concentration, morphologies such as honeycomb-like films, surfaces of aggregated large porous spheres, or pincushion-like spheres with protruding tubular vesicle aggregates are observed. These surface-patterned films show significantly enhanced hydrophobicity. The results suggest that a superhydrophobic . behavior can be achieved, with a maximum contact angle of 158 degrees, by using the pincushion-like micellar structure.
Pentacene-based thin-film transistors with multiwalled carbon nanotube source and drain electrodes
(2007-08-20)
Chang, Chia-Hao
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Chien, Chao-Hsin
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Yang, Jung-Yen
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
In this letter, the authors propose a practical and reliable approach-using deposited multiwalled carbon nanotubes (MWCNTs) as source and drain electrodes-for reducing the contact resistance (R-c) in pentacene-based bottom-contact thin-film transistors. The value of R-c of the devices was closely linked to the resultant length of the deposited MWCNTs; the lowest value was 3x10(8) Omega mu m. The largest saturation mobility was 0.14 cm(2)/V s; this value reached up to three times higher when the threshold voltage was determined using the maximum transconductance (G(m,max)) extrapolation method, rather than the constant current method. The on/off ratio was more than 10(6). (C) 2007 American Institute of Physics.
交大e-News第008期
(2007-08-20)
Secretariat
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國立交通大學秘書室
Efficient deep blue emitters for organic electroluminescent devices
(2007-08-20)
Ho, Meng-Huan
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Wu, Yao-Shan
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Wen, Shih-Wen
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Chen, Teng-Ming
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Chen, Chin H.
Highly efficient deep blue organic light emitting devices have been fabricated with a 4-(styryl)biphenyl-core based fluorescent dopant (SK-1) in the wide band gap 2-methyl-9,10-di(1-naphthyl)anthracene (alpha,alpha-MADN) host system which achieved an electroluminescence efficiency of 5.0 cd/A and an external quantum efficiency of 4.2% at 20 mA/cm(2) with a saturated blue Commission Internationale de l'Eclairage coordinates of (0.15, 0.14) and a half-decay lifetime of 8000 h at an initial brightness of 100 cd/m(2). The current efficiency and electroluminescent color of SK-1 doped devices have been shown to be essentially immune to drive current density. (C) 2007 American Institute of Physics.
Growth of GaAs epitaxial layers on Si substrate by using a novel GeSi buffer layer
(2007-08-21)
Chang
;
Edward Y.
;
Luo
;
Guangli
;
Yang
This invention provides a process for growing Ge epitaxial layers on Si substrate by using ultra-high vacuum chemical vapor deposition (UHVCVD), and subsequently growing a GaAs layer on Ge film of the surface of said Ge epitaxial layers by using metal organic chemical vapor deposition (MOCVD).The process comprises steps of, firstly, pre-cleaning a silicon wafer in a standard cleaning procedure, dipping it with HF solution and prebaking to remove its native oxide layer. Then, growing a high Ge-composition epitaxial layer, such as Si0.1Ge0.9in a thickness of 0.8 μm on said Si substrate by using ultra-high vacuum chemical vapor deposition under certain conditions. Thus, many dislocations are generated and located near the interface and in the low of part of Si01.Ge0.9due to the large mismatch between this layer and Si substrate.Furthermore, a subsequent 0.8 μm Si0.05Ge0.95layer, and/or optionally a further 0.8 μm Si0.02Ge0.98layer, are grown. They form strained interfaces of said layers can bend and terminate the propagated upward dislocation very effectively. Therefore, a film of pure Ge is grown on the surface of said epitaxial layers.Finally, a GaAs epitaxial layer is grown on said Ge film by using MOCVD.