Browsing by Issue Date, starting with "1996-10-07"

Now showing 1 - 20 of 84998

Mixed-metal oxide films via a heterobimetallic complex as an MOCVD single-source precursor
(1996-10-07)
Shyu, SG
;
Wu, JS
;
Chuang, SH
;
Chi, KM
;
Sung, YS
A single-phase polycrystalline mixed-metal oxide WCoO4 film on Si(100) can be prepared by MOCVD with the use of [(eta-C5H5)(CO)(3)WCo(CO)(4)] as a single-source precursor.
Synthesis of second-order nonlinear optical chromophores with enhanced thermal stability and nonlinearity: A conformation-locked trans-polyene approach
(1996-10-07)
Shu, CF
;
Tsai, WJ
;
Chen, JY
;
Jen, AKY
;
Zhang, Y
A facile synthesis that combines the use of an easily polarizable thiophene ring and a ring-locked triene as efficient conjugating moieties is employed to simultaneously enhance molecular nonlinearity (as high as 13 000 x 10(-48) esu) and thermal stability; incorporating this highly nonlinear chromophore in polyquinoline results in high electrooptic activity and long-term alignment stability at 100 degrees C for more than 1000 h.
Intramolecular Diels-Alder reaction of furans with allenyl ethers followed by trimethylsilyl group 1,2-rearrangement and Brook rearrangement
(1996-10-07)
Wu, HJ
;
Yen, CH
;
Chuang, CT
;
應用化學系
;
Department of Applied Chemistry
The base-catalyzed intramolecular Diels-Alder reactions of 5-trimethylsilyl-2-furfuryl propargyl ethers la-lf gave compounds 2a-2f and 3a-3f in 70-90% yields respectively, a novel reaction involving an intramolecular Diels-Alder reaction followed by a trimethylsilyl group 1,2-rearrangement and Brook rearrangement. Copyright (C) 1996 Elsevier Science Ltd
Intramolecular Diels-Alder reaction of furans with allenyl ethers followed by trimethylsilyl group 1,2-rearrangement and Brook rearrangement
(1996-10-07)
Wu, HJ
;
Yen, CH
;
Chuang, CT
;
交大名義發表
;
應用化學系
The base-catalyzed intramolecular Diels-Alder reactions of 5-trimethylsilyl-2-furfuryl propargyl ethers la-lf gave compounds 2a-2f and 3a-3f in 70-90% yields respectively, a novel reaction involving an intramolecular Diels-Alder reaction followed by a trimethylsilyl group 1,2-rearrangement and Brook rearrangement. Copyright (C) 1996 Elsevier Science Ltd
Parallelizing a level 3 BLAS library for LAN-connected workstations
(1996-10-10)
Huang, KC
;
Wang, FJ
;
Wu, PC
;
交大名義發表
;
資訊工程學系
LAN-connected workstations are a heterogeneous environment, where each workstation provides time-varying computing power, and thus dynamic load balancing mechanisms are necessary for parallel applications to run efficiently. Parallel basic linear algebra subprograms (BLAS) have recently shown promise as a means of taking advantage of parallel computing in solving scientific problems. Most existing parallel algorithms of BLAS are designed for conventional parallel computers; they do not take the particular characteristics of LAN-connected workstations into consideration. This paper presents a parallelizing method of Level 3 BLAS for LAN-connected workstations. The parallelizing method makes dynamic load balancing through column-blocking data distribution. The experiment results indicate that this dynamic load balancing mechanism really leads to a more efficient parallel level 3 BLAS for LAN-connected workstations. (C) 1996 Academic Press, Inc.
Parallelizing a level 3 BLAS library for LAN-connected workstations
(1996-10-10)
Huang, KC
;
Wang, FJ
;
Wu, PC
;
資訊工程學系
;
Department of Computer Science
LAN-connected workstations are a heterogeneous environment, where each workstation provides time-varying computing power, and thus dynamic load balancing mechanisms are necessary for parallel applications to run efficiently. Parallel basic linear algebra subprograms (BLAS) have recently shown promise as a means of taking advantage of parallel computing in solving scientific problems. Most existing parallel algorithms of BLAS are designed for conventional parallel computers; they do not take the particular characteristics of LAN-connected workstations into consideration. This paper presents a parallelizing method of Level 3 BLAS for LAN-connected workstations. The parallelizing method makes dynamic load balancing through column-blocking data distribution. The experiment results indicate that this dynamic load balancing mechanism really leads to a more efficient parallel level 3 BLAS for LAN-connected workstations. (C) 1996 Academic Press, Inc.
A voltage-tunable multicolor triple-coupled InGAs/GaAs/AlGaAs quantum-well infrared photodetector for 8-12 mu m detection
(1996-10-14)
Chiang, JC
;
Li, SS
;
Tidrow, MZ
;
Ho, P
;
Tsai, M
A voltage-tunable multicolor triple-coupled quantum-well infrared photodetector (TC-QWIP) has been developed for 8-12 mu m detection. The TC-QWIP consists of three coupled quantum wells formed by an enlarged Si-doped InxGa1-xAs quantum well and two undoped GaAs quantum wells separated by two thin AlyGa1-yAs barriers. Two TC-QWIP structures with varying indium and aluminum compositions were designed and demonstrated. Due to the strong coupling effect of the asymmetrical quantum wells, three bound states (E(1), E(2), E(3)) are formed inside the quantum wells of the TC-QWIP. The main detection peak wavelength is due to E(1)-->E(3) bound states transition for both devices, while two secondary detection peaks due to E(1)-->E(2) and E(1)-->E(c) continuum states transitions under different biases were also observed. In addition, a strong quantum-confined Stark shift effect for the E(1)-->E(3) transition was observed in the wavelength range of 8.2-9.1 and 10.8-11.5 mu m for QWIP-A and QWIP-B, respectively; both devices exhibit a linear dependence of detection peak wavelength on the applied bias voltage. A spectral responsivity of R(i)=0,05 A/W and background limited performance (BLIP) detectivity D-BLIP*=6.1x10(9) cm root HZ/W were obtained at V-b=5 V, lambda(p)=8.6 mu m, and T-BLIP=66 K for QWIP-A, while R(i)=0.33 A/W and D-BLIP*=1.63x10(10) cm root Hz/W at V-b=4 V, pi(p)=11.2. mu m, and T-BLIP-50 K were obtained for QWIP-B. (C) 1996 American Institute of Physics.
A voltage-tunable multicolor triple-coupled InGAs/GaAs/AlGaAs quantum-well infrared photodetector for 8-12 mu m detection
(1996-10-14)
Chiang, JC
;
Li, SS
;
Tidrow, MZ
;
Ho, P
;
Tsai, M
A voltage-tunable multicolor triple-coupled quantum-well infrared photodetector (TC-QWIP) has been developed for 8-12 mu m detection. The TC-QWIP consists of three coupled quantum wells formed by an enlarged Si-doped InxGa1-xAs quantum well and two undoped GaAs quantum wells separated by two thin AlyGa1-yAs barriers. Two TC-QWIP structures with varying indium and aluminum compositions were designed and demonstrated. Due to the strong coupling effect of the asymmetrical quantum wells, three bound states (E(1), E(2), E(3)) are formed inside the quantum wells of the TC-QWIP. The main detection peak wavelength is due to E(1)-->E(3) bound states transition for both devices, while two secondary detection peaks due to E(1)-->E(2) and E(1)-->E(c) continuum states transitions under different biases were also observed. In addition, a strong quantum-confined Stark shift effect for the E(1)-->E(3) transition was observed in the wavelength range of 8.2-9.1 and 10.8-11.5 mu m for QWIP-A and QWIP-B, respectively; both devices exhibit a linear dependence of detection peak wavelength on the applied bias voltage. A spectral responsivity of R(i)=0,05 A/W and background limited performance (BLIP) detectivity D-BLIP*=6.1x10(9) cm root HZ/W were obtained at V-b=5 V, lambda(p)=8.6 mu m, and T-BLIP=66 K for QWIP-A, while R(i)=0.33 A/W and D-BLIP*=1.63x10(10) cm root Hz/W at V-b=4 V, pi(p)=11.2. mu m, and T-BLIP-50 K were obtained for QWIP-B. (C) 1996 American Institute of Physics.
Fabrication and physical properties of radio frequency sputtered Cd1-xMnxS thin films
(1996-10-15)
Tsai, CT
;
Chen, SH
;
Chuu, DS
;
Chou, WC
;
電子物理學系
Highly oriented Cd1-xMnxS thin films with a wurtzite structure were grown by the radio-frequency sputtering technique. The grain size of the Cd1-xMnxS thin films was found to decrease with an increase in the Mn concentration x. Moreover, the lattice softening effect due to the quantum size effect, the band-bowing phenomena accounted for by the band-gap correction arising from the chemical disorder, and the exchange interaction between the band carrier and the d electron of the magnetic Mn ions have been investigated.
Fabrication and physical properties of radio frequency sputtered Cd1-xMnxS thin films
(1996-10-15)
Tsai, CT
;
Chen, SH
;
Chuu, DS
;
Chou, WC
;
電子物理學系
Highly oriented Cd1-xMnxS thin films with a wurtzite structure were grown by the radio-frequency sputtering technique. The grain size of the Cd1-xMnxS thin films was found to decrease with an increase in the Mn concentration x. Moreover, the lattice softening effect due to the quantum size effect, the band-bowing phenomena accounted for by the band-gap correction arising from the chemical disorder, and the exchange interaction between the band carrier and the d electron of the magnetic Mn ions have been investigated.
Hindered and modulated rotational states and spectra of adsorbed diatomic molecules
(1996-10-15)
Shih, YT
;
Chuu, DS
;
Mei, WN
;
電子物理學系
;
光電工程研究所
Both vertical and horizontal adsorption configurations of a diatomic molecule were modeled as the rigid rotor with which thr spatial motion was confined by a finite conical well. In addition to the polar hindering potential, a sinusoidal azimuthal modulation. which bears the local symmetry of the adsorption site, was incorporated. Eigenfunctions for different models were expressed analytically in terms of the hypergeometric functions, and eigenvalues were solved numerically. We found that the rotational energy levels exhibit oscillatory behavior when plotted as functions of the hindrance angle. This particular phenomenon was interpreted as the occurrence of resonance transmission of the rotor wave function at certain hindrance condition. We also found that the rotational levels were grouped into bands when the azimuthal modulation strength was increased. The solutions were used to calculate the rotational-state distribution of desorbed molecules, and agreement with the previous experiment was obtained.
In situ fracture observation of a TiC/Ti MMC produced by combustion synthesis
(1996-10-15)
Tsang, HT
;
Chao, CG
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Ma, CY
;
材料科學與工程學系
;
Department of Materials Science and Engineering
劍橋之柳
(1996-10-28)
管管
Enhancement of pool boiling heat transfer in a horizontal water layer through surface roughness and screen coverage
(1996-11-01)
Tsay, JY
;
Yan, YY
;
Lin, TF
;
機械工程學系
;
Department of Mechanical Engineering
An experimental investigation was carried out to study the augmentation of heat transfer in saturated pool boiling of a liquid water layer on a heated horizontal stainless steel plate by roughing the surface and/or covering it with a single layer of stainless steel screen. The results were presented in terms of the boiling curves. Effects of various parameters - the surface roughness, liquid level and size of the stainless steel mesh on the boiling heat transfer were examined in detail. The measured data clearly indicated that a lowering of the liquid level from 60 to 5 mm in water depth causes heat transfer reduction. Roughing the surface was found to significantly enhance the heat transfer. Use a layer of metal screen to cover the heated surface was shown to substantially augment the heat transfer especially for a shallow water layer if the mesh size is comparable with the bubble departure diameter. Covering the rough surface with the metal mesh, however, reduced the heat transfer.
Low-temperature and low thermal budget fabrication of polycrystalline silicon thin-film transistors
(1996-11-01)
Lin, HY
;
Chang, CY
;
Lei, TF
;
Liu, FM
;
Yang, WL
A top-gate self-aligned n-channel polycrystalline silicon (poly-Si) thin-film transistor (TFT) has been fabricated with low temperature (less than or equal to 550 degrees C) and low thermal budget process. The ultrahigh vacuum chemical vapor deposition (UHV/CVD) grown poly-Si was served as the channel film, the chemical mechanical polishing (CMP) technique was used to polish the channel surface, plasma-enhanced chemical vapor deposited (PECVD) tetraethylorthosilicate (TEOS) oxide was used as the gate dielectric, and NH3 plasma was used to passive the device. In this process, the solid phase crystallization (SPC) step Is not needed. A field effect mobility of 46 cm(2)/V-s, ON/OFF current ratio of over 10(7), and threshold voltage of 0.8 V are obtained. The significant reduction in process temperature and thermal budget make this process advantageous for larger-area-display peripheral driver circuits on glass substrate.
Characterization of boron silicide layer deposited by ultrahigh-vacuum chemical-vapor deposition
(1996-11-01)
Tseng, HC
;
Pan, FM
;
Chang, CY
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Deposition of a boron-containing layer using B2H6 diluted with H-2 on a Si(001) surface has been carried out in an ultrahigh-vacuum chemical-vapor-deposition (UHV-CVD) system. The deposited boron-containing layers were characterized by atomic force microscope and Auger electron spectroscopy (AES), and the junction depth was determined by secondary-ion-mass spectroscopy. Effective doping is accomplished before perceivable nucleation is initiated. Islands are first formed on the substrate surface at a small dose of diborane, and the grains coalesce to form a rough him for higher doses. At growth temperature above 800 degrees C, the film is composed of possibly SiB6, according to AES depth profiles. Correlation between the junction depth and the sheet resistance of the UHV-CVD-deposited specimens prepared under various conditions is discussed. Postdeposition rapid thermal annealing was performed to study the effect of subsequent thermal cycles on the junction depth and sheet resistance. (C) 1996 American Institute of Physics.
Departure process analysis for earliest-due-date scheduling discipline in ATM switches
(1996-11-01)
Liang, ST
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Yuang, MC
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交大名義發表
;
資訊工程學系
;
National Chiao Tung University
Asynchronous Transfer Mode (ATM) networks are expected to support to diverse mix of traffic sources demanding different Quality Of Service (QOS) guarantees. Regarding the Earliest-Due-Date (EDD) as one of the most promising scheduling disciplines offering delay guarantees in ATM switches, we provided in our previous work a decent queueing analysis for determining the urgency number (D-i) for each service class in an effort to offer 99% delay guarantees for higher delay priority calls under various traffic loads. To further evaluate the end-to-end delay distribution for an observed call, in this paper we present the departure process analysis for the EDD discipline with two urgency numbers D-0 = 0 and D-1 = D associated with two delay-based service classes (class 0 and class 1), respectively. The EDD-based ATM switch is modelled by a discrete-time, single-server queueing system with renewal and non-renewal arrivals. Based on the queueing model, we derive the interdeparture time distribution for the observed traffic stream being multiplexed with other traffic streams. The accuracy of the analysis is confirmed by simulation results. Numerical results demonstrate the characteristic reform of the periodic traffic stream after multiplexing through an EDD-based ATM switch. Since the derived departure process becomes the arrival process of the subsequent ATM switch along the pre-established virtual route, the analysis offers the realization of end-to-end delay computation for ATM networks.
Effect of thin film coating of Au on joint strength in Invar-Invar packages
(1996-11-01)
Wang, SC
;
Wang, CM
;
Wang, C
;
Chang, HL
;
Tu, YK
The effect of a thin film coating of Au on the joint strength, weld width, and penetration depth in laser welding techniques for Invar-Invar packages is investigated experimentally. It is found that the joint strength, weld width, and penetration depth are strongly dependent on the coating of Au thickness on the Invar material. The welded joints with thick Au coating show narrower weld width, shallower penetration, and hence less joint strength than those of the packages with thin Au coating. The increase in both the thermal conductivity and the vapor volume in the welded joints as the coating of Au thickness increases are the possible mechanisms for the reduction. Detailed knowledge of the effect of thin film coatings of Au on the welded materials, which gives both the highest joint strength and good adhesion, is essential for practical design and fabrication of reliable optoelectronic packaging.
Deep levels, electrical and optical characteristics in SnTe-doped GaSb Schottky diodes
(1996-11-01)
Chen, JF
;
Chen, NC
;
Liu, HS
;
交大名義發表
;
電子物理學系
The GaSb layers investigated were grown directly on GaAs substrates by molecular beam epitaxy (MBE) using SnTe source as the n-type dopant. By using admittance spectroscopy, a dominant deep level with the activation energy of 0.23-0.26 eV was observed and its concentration was affected by the Sb-4/Ga flux ratio in the MBE growth. A lowest deep-level concentration together with a highest mobility was obtained for GaSb grown at 550 degrees C under a Sb-4/Ga beam equivalent pressure (BEP) ratio around 7, which should correspond to the lowest ratio to maintain a Sb-stabilized surface reconstruction. In the Hall measurement, an analysis of the temperature-dependent mobility shows that the ionized impurity concentration increases proportionally with the sample's donor concentration, suggesting that the ionized impurity was introduced by an SnTe source. In addition, optical properties of an undoped p-, a lightly and heavily SnTe-doped GaSb layers were studied by comparing their photoluminesence spectra at 4.5K.
A queue manager chip for shared buffer ATM switches
(1996-11-01)
Lin, YS
;
Huang, HC
;
Shung, CB
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This paper presents an efficient queue manager chip for controlling a 16 x 16 shared buffer ATM switch with a 256-cell buffer. Compared to conventional implementations of queue managers for shared buffer ATM switches, our design eliminates the idle address FIFO and the pre-allocated bubbles at the tails of output queues. The former reduces the storage size required for queue management, while the latter improves the effective buffer capacity. Such modular implementation also provides flexibilities in queue management implementation. Backpressure with soft-full and hard-full flow control for multi-stage expansion and two priority classes with push-out cell discarding are supported without extra hardware overhead. This chip was designed and fabricated using 0.8 mu m CMOS technology. It has 35,700 transistors in a chip area of 28.3 mm(2), with a core of 10.4 mm(2) and 31,960 transistors. Two test sequences were developed during the design phase to fully verify the queue management functions of the prototype chip. The queue manager chip was tested up to 36 MHz, and is able to control a 16 x 16 shared buffer switch with a 155 MHz link rate.