Browsing by Issue Date, starting with "2004-01-15"

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Hydrogen bonding effect on the poly(ethylene oxide), phenolic resin, and lithium perchlorate-based solid-state electrolyte
(2004-01-15)
Chen, HW
;
Jiang, CH
;
Wu, HD
;
Chang, FC
;
應用化學系
The interaction behavior of solid-state polymer electrolytes composed of poly(ethylene oxide) (PEO)/novolac-type phenolic resin and lithium perchlorate (Li-ClO4) was investigated in detail by DSC, FTIR, ac impedance, DEA, solid-state NMR, and TGA. The hydrogen bonding between the hydroxyl group of phenolic and ether oxygen of the PEO results in higher basicity of the PEO. The higher basicity of the ether group can dissolve the lithium salts more easily and results in a greater fraction of "free" anions and thus higher ionic conductivity. DEA results demonstrated that addition of the phenolic increases the dielectric constant because of the partially negative charge on the ether group induced by the hydrogen bonding interaction between ether oxygen and the hydroxyl group. The study showed that the blend of PEO(100)/LiClO4(25)/phenolic(15) possesses the highest ionic conductivity (1.5 X 10(-5) S cm(-1)) with dimensional stability. (C) 2003 Wiley Periodicals, Inc.
Novel polymer electrolyte composed of poly(ethylene oxide), lithium triflate, and benzimidazole
(2004-01-15)
Chen, HW
;
Xu, HY
;
Huang, CF
;
Chang, FC
;
應用化學系
This work has demonstrated that the incorporation of benzimidazole derivatives, 2,2'-p-phenylene-bisindole (PPBI), enhances the ionic conductivity of a poly(ethylene oxide) (PEO)-based electrolyte by 20 times more than the plain system. Specific interactions among amino group, ethyl oxide, and lithium cation were investigated using differential scanning calorimetry (DSC), FTIR, and alternating current impedance. The DSC characterization confirms that the initial addition of PPBI is able to enhance the PEO crystallinity attributed to the interaction between the negative charge from the amino group and the lithium cation. Three types of complexes are present: complex I is present in the PEO phase, complex 11 resides at interphase, and complex III is located within the PPBI domain. Complex II plays the key role in stabilizing these two microstructure phases. FTIR spectra confirm that because of the presence of PPBI one is able to dissolve lithium salts more easily than in the plain electrolyte system and thus increase the fraction of free ions. (C) 2003 Wiley Periodicals, Inc.
Active electrostatic discharge (ESD) device for on-chip ESD protection in sub-quarter-micron complementary metal-oxide semiconductor (CMOS) process
(2004-01-15)
Ker, MD
;
Tseng, TK
;
電機學院
;
College of Electrical and Computer Engineering
A novel electrostatic discharge (ESD) protection device with a threshold voltage of similar to0V for complementary metal-oxide semiconductor (CMOS) integrated circuits in sub-quarter-micron CMOS technology is proposed. Quite different to the traditional ESD protection devices, such an active ESD device is originally standing in its turn-on state when the IC is zapped under ESD events. Therefore, such an active ESD device has the fastest turn-on speed and the lowest turn-on voltage to effectively protect the internal circuits with a much thinner gate oxide in future sub-0.1 mum CMOS technology. The proposed active ESD device is fully process-compatible to the general sub-quarter-micron CMOS process.
Integration of a stack of two fluorine doped silicon oxide film with ULSI interconnect metallization
(2004-01-15)
Cheng, YL
;
Wang, YL
;
Liu, CP
;
Wu, YL
;
Lo, KY
Recently, fluorosilicate glass (FSG) has received much attention for application in microelectronics manufacturing due to its low dielectric constant and stable gap-filling ability. Although FSG films have been demonstrated as potential inter metal dielectrics (IMD) for sub-micron devices, integrating a stack of two fluorine doped silicon oxide film deposited on a high-density plasma chemical vapor deposition (HDP-CVD) system for gap filling and a plasma-enhanced chemical vapor deposition (PECVD) system for throughput has not been fully investigated. In this research, an excellent and exceptionally stable process was demonstrated for a stack of HDP-CVD FSG and PECVD FSG layers. Cracks that result from multi-level metal technology were eliminated when higher compressive stress PECVD FSG film was implemented as a capping layer. An 11% capacitance reduction was achieved when comparing a stack of FSG films to undoped silicon oxide. No problem occurred for photo, via etching and chemical mechanical polishing of FSG film. The FSG layer stack's via resistance (Rc(-)Via) as well as a full HDP-FSG scheme is comparable. These results are very promising for the integration of FSG films as inter metal dielectric for devices. (C) 2003 Elsevier B.V. All rights reserved.
Characteristics of stable emission GaN-based resonant-cavity light-emitting diodes
(2004-01-19)
Lin, CF
;
Yao, HH
;
Lu, JW
;
Hsieh, YL
;
Kuo, HC
The resonant-cavity light-emitting diode (RC-LED) structure was grown by MOCVD. The structure of RC-LED consisted of a 3lambda InGaN/GaN MQW LED cavity between the top TiO2/SiO2 DBR (81.7%, reflectance) and the bottom AlN/GaN DBR (90.4%) stack. A stable 410 nm emission peak and a low thermally induced red-shift effect (0.12 nm/kA/cm(2)) were measured by varying the injection current density. The light output power of the full RC-LED device was three times higher than the RC-LED without top TiO2/SiO2 DBR layers under 600 A/cm(2) inject current density. The narrow line width of 7.4 nm, emission peak localization at 410 nm, and three times higher output power were caused by the resonance effect in this vertical cavity structure. (C) 2003 Published by Elsevier B.V.
MOCVD growth of high-performance InGaAsP/InGaP strain-compensated VCSELs with 850 nm emission wavelength
(2004-01-19)
Kuo, HC
;
Chang, YS
;
Lin, CF
;
Lu, TC
;
Wang, SC
We present in this paper the metalorganic chemical vapor deposition growth and characterization of high-performance 850 nm InGaAsP/InGaP strain-compensated MQWs vertical-cavity surface-emitting lasers (VCSELs). The InGaAsP/InGaP MQWs growth condition was optimized using photoluminescence. These VCSELs exhibit superior characteristics, with threshold currents similar to 0.4 mA, and slope efficiencies similar to 0.6 mW/mA. The threshold current change is less than 0.2 mA and the slope efficiency drops by less than similar to 30% when the substrate temperature is raised from room temperature to 85degreesC. These VCSELs also demonstrate high-speed modulation bandwidth up to 12.5 Gbit/s from 25degreesC to 85degreesC. (C) 2003 Elsevier B.V. All rights reserved.
Convergent electron beam induced growth of copper nanostructures: Evidence of the importance of a soft template
(2004-01-20)
Yen, MY
;
Chiu, CW
;
Chen, FR
;
Kai, JJ
;
Lee, CY
In a transmission electron microscope, CuCl particles were irradiated by a convergent electron beam (CEB, 200 kV, 200 pA/cm(2), beam diameter of ca. 1-2 mum) to induce growth of copper nanostructures. Upon CEB irradiation, Cu nanoparticles (5-20 nm in diameter) were formed from commercial CuCl. Using synthesized CuCl encapsulated in permethylpolysilane, growth of polycrystalline copper nanowires (50-200 nm in diameter and up to 30 mum in length) was observed. Evolution of Cu nanoparticles from the synthesized CuCl was observed from the positions with apparent incomplete encapsulation. The effect of polymer encapsulation, acting as a soft template, is shown to be important to influence the nanostructure growth. The observation supports the vapor-solid reaction growth model.
快速分配音訊位元之方法
(2004-01-21)
李俊毅
;
莊孝強
;
方耀諄
;
王俊能
;
蔣迪豪
一種快速分配音訊位元之方法，主要係以整體量化增益(globalgain)以及所使用之位元量(bit)間的線性關係(linearrelationship)建立線性模型，並配合平行化之量化誤差計算而取得音頻編碼所需之位元量，藉以改善傳統包括外部(量化雜訊控制)、內部(碼率控制)雙重回圈耗功費時之運算過程，提升整體的編碼速度，並保持一定水平之音訊品質。
METHOD FOR TRANSFERRING EPITAXY LAYER
(2004-01-22)
YewChung, Wu
;
PeiYan, Lin
A method for transferring an epitaxy layer is provided. The method includes steps of (a) providing a first substrate, (b) forming a first epitaxy layer on the first substrate, (c) forming a masking layer having at least a pattern on the first epitaxy layer, (d) forming a second epitaxy layer on the masking layer, (e) bonding a second substrate to the second epitaxy layer, and (f) removing the masking layer and separating the second epitaxy layer from the first epitaxy layer, thereby the second epitaxy layer being transferred to the second substrate.
Determination of optimal exciter deployment for panel speakers using the genetic algorithm
(2004-01-22)
Bai, MR
;
Liu, BW
;
機械工程學系
;
Department of Mechanical Engineering
A large multi-exciter panel speaker has been constructed in this work. In order to achieve the best design, an optimization procedure using the genetic algorithm (GA) has been developed. A total numerical model was first established for simulation, where the electrical system, the mechanical system, and the acoustical coupling in the panel speaker are accounted for within a coupled framework. Performance indices including the frequency response, the sound power, and the directional response are calculated. The simulation model also serves as the basis for the optimal design that aims at achieving omni-directional responses at high efficiencies. A GA-based optimization scheme was exploited to search for the positions of exciters and the delays of input signals which render the optimal performance. The optimal design was verified by experimental investigations. The results indicate that the optimal configuration indeed produced better performance in terms of efficiency and omni-directionality than the non-optimal one. (C) 2003 Elsevier Science Ltd. All rights reserved.
Intervention of phenonium ion in Ritter reactions
(2004-01-23)
Ho, TL
;
Chein, RJ
;
應用化學系
;
Department of Applied Chemistry
The transformation of phenylethyl chloride to 3,4-dihydroisoquinolines is shown to proceed via phenonium ion. The evidence comes from a study of dideuterated analogue 4, and the monomethylated and dimethylated compounds 2 and 3.
One-polymer active pixel
(2004-01-26)
Tzeng, KL
;
Meng, HF
;
Tzeng, MF
;
Chen, YS
;
Liu, CH
A metal-oxide field-effect transistor (MOSFET) based on an electroluminescent conjugated polymer is fabricated on a glass substrate. It is found that the mobility horizontal to the substrate is two to three orders of magnitude larger than the mobility vertical to the substrate. The high horizontal mobility is attributed to the in-plane chain alignment in amorphous spin-coated films. We demonstrate an active pixel in which the light-emitting diode and the driving MOSFET share the same active polymer. (C) 2004 American Institute of Physics.
A side-chain dendronized nonlinear optical polyimide with large and thermally stable electrooptic activity
(2004-01-27)
Luo, JD
;
Haller, M
;
Li, HX
;
Tang, HZ
;
Jen, AKY
音声信号を送信およびパックするためのデジタル符号化方法およびアーキテクチャ
(2004-01-29)
劉　▲啓▼民
;
李　文傑
【課題】高い品質とより低い計算の複雑さを有する、音声信号の送信およびパックのためのデジタル符号化方法を提供すること。【達成手段】デジタル符号化方法は、入力音声信号を、音声信号のスペクトル構成を表す周波数サンプルのシーケンスに変換し、かつ、これを、マスク閾値を参照することによって量子化パラメータを評価するためのパラメータ予測器を用いるビット割当装置に従い、量子化する。量子化された値は、いくつかのビットからなるデータへと符号化される。繰り返しのレート制御ループが、符号化されるビット数が符号化されるデータに利用可能な指定のビット数を超えると、量子化パラメータおよび量子化ステップサイズを調節する。また、入力音声信号の高周波成分を、繰り返しレート制御ループによって決定されたカットオフ周波数に従って、周波数サンプルのシーケンスを量子化する前にカットオフすることができる。【選択図】　　　図１
Schottky structure in GaAs semiconductor device
(2004-01-29)
Cheng-Shih, Lee
;
Yi, Chang
The present invention provides a Schottky Structure in gallium arsenide (GaAs) semiconductor device, which comprises a gallium arsenide (GaAs) semiconductor substrate, a titanium (Ti) layer on a surface of said gallium arsenide (GaAs) semiconductor substrate to form Schottky contact, a diffusion barrier layer on a surface of said titanium (Ti) layer to block metal diffusion, and a first copper layer on a surface of said diffusion barrier layer.
Evaluation of advanced chemical mechanical planarization techniques for copper damascene interconnect
(2004-01-30)
Chen, KW
;
Wang, YL
;
Liu, CP
;
Yang, K
;
Chang, L
According to rapid development of CMP technology, the difference of polishing methods would be applied for copper damascene interconnect. These methods include conventional rotary, linear, oscillation platform. The advantages of these platform would highlighted in uniformity control, stability of removal rate, planarization efficiency, throughput promotion, lower cost of ownership, even dishing and erosion effect integrated with slurry. This paper presented our experience to compare the uniformity, removal rate and planarization efficiency of Cu-CMP between various polishing platforms. In convection, the rotary or oscillation platform would be usually applied in oxide and tungsten CMP, due to the robust air-back carrier and rigid platen to polish the wafer, which performs the good reliability on wafer-to-wafer thickness and endpoint detection. However, the linear polisher is made of the air-bearing moving belt and self-rotated carrier and would provide the wider uniformity and planarization control window than others. In addition,, the simulation model would explain the difference from mechanic design and wafer moving paths between various polishing techniques. Hence, the trade-off advantage and application between various platforms would be compensated and integrated with slurry, conditioners and coming thickness profile from copper plating. It can achieve the optimization of Cu-CMP process. (C) 2003 Elsevier B.V. All rights reserved.
Study on precipitations of fluorine-doped silicon oxide
(2004-01-30)
Wu, J
;
Wang, YL
;
Liu, CP
;
Chang, SC
;
Kuo, CT
Precipitation on fluorine-doped silicon oxide film (SiOF) was observed while exposure to air for a prolonged period of time (>4 h). Most of the precipitates are less than 1 mum and clustered at wafer center. Under SEM view, the precipitation shows hexagonal shape, and mainly composed of Si and O. SIMS analysis showed that SiOF films without F precipitates showed leveling F% profile, whereas SIMS result for SiOF films with precipitations shows increasing gradient with depth. In this study, factors affecting the precipitation of SiOF film were investigated. Humidity in environment was found to be one of the essential elements for the onset of precipitation. Process optimization and control methodologies were also investigated for precipitation prevention to provide a more robust and stable SiOF film, hence ensuring the reliability of device performance. (C) 2003 Elsevier B.V. All rights reserved.
Copper surface protection with a completely enclosed copper structure for a damascene process
(2004-01-30)
Wang, TC
;
Hsieh, TE
;
Wang, YL
;
Wu, YL
;
Lo, KY
As integrated circuit manufacture moving to copper interconnection for the most advanced products, protection of copper (Cu) surfaces becomes a major challenge for the back-end-of-line manufacturing process. The damages on Cu, such as Cu corrosion and oxidation, are often observed on wafers when exposing bare Cu surface in the presence of moisture and/or acidic gases. Furthermore, the Cu oxide results in poor adhesion both at Cu/barrier layer and Cu/stop layer interfaces. In this work, a novel Cu dual damascene structure which completely encloses the Cu surface with a tantalum nitride layer is presented. This capping layer avoids the Cu corrosion and oxidation due to its ability to keep moisture and acid off and away from the Cu surface. (C) 2003 Elsevier Science B.V. All rights reserved.
Effects of the Sb2Te3 crystallization-induced layer on crystallization behaviors and properties of phase change optical disk
(2004-01-30)
Wang, WH
;
Chung, LC
;
Kuo, CT
;
材料科學與工程學系
;
Department of Materials Science and Engineering
The conventional phase-change optical disk is generally fabricated by the sputtering process, which has a drawback of requiring an initialization process to change the as-deposited recording layer in the disk from amorphous to crystalline phases before the disk can be used for reading or writing. In order to develop an initialization-free process, the Sb2Te3, alloy was used as an additional layer below or above the recording Ge2Sb2Te5 layer to study its effect on crystallization behaviors of the recording layer. The layer structures were deposited on substrates of Si wafer, Cu-mesh to examine crystal structure (XRD), amorphous-to-crystal transformation (DSC) and microstructure (TEM). The complete disk specimens were prepared on PC board to measure their dynamic properties, such as reflectivity, jitter and modulation (dynamic tester); and to examine the effects of laser pulse duration time, position and thickness of Sb2Te3, layer on static reflectivity of the disk (static tester), where Avrami coefficient 'q' in J-M-A rate equation can be derived. The results show that effect of Sb2Te3 layer is essentially to induce crystallization of Ge2Sb2Te5, recording layer from (110) plane of Sb2Te3 crystals. This is due to the fact that the crystallization temperature of Sb2Te3 crystal is 85 degreesC below that of Ge2Sb2Te5 crystal, in addition to a lower lattice mismatch between two crystals. The is in agreement with the J-M-A kinetic analyses that the rate controlling step for amorphous-crystal transformation in disk specimens with Sb2Te3 layer over 15-nm thickness is mainly governed by nucleation with q = 2.53-2.79 > 2.5 in J-M-A equation. Regarding the effects of Sb2Te3 layer on disk properties, the results show that under the 10 nm Ge2Sb2Te5, layer thickness, the Sb2Te3 assisted disks with lower Sb2Te3 layer thickness between 13 and 20 nm show the best combination of reflectivity and modulation. The most important advantage of this process is that the Sb2Te3-assisted disks require no initialization process, because the as-deposited disks can be directly written and erased. (C) 2003 Elsevier B.V. All rights reserved.
On some super fault-tolerant Hamiltonian graphs
(2004-01-30)
Chen, YC
;
Tsai, CH
;
Hsu, LH
;
Tan, JJM
;
資訊工程學系
A k-regular Hamiltonian and Hamiltonian connected graph G is super fault-tolerant Hamiltonian if G remains Hamiltonian after removing at most k - 2 nodes and/or edges and remains Hamiltonian connected after removing at most k - 3 nodes and/or edges. A super fault-tolerant Hamiltonian graph has a certain optimal flavor with respect to the fault-tolerant Hamiltonicity and Hamiltonian connectivity. In this paper, we investigate a construction scheme to construct super fault-tolerant Hamiltonian graphs. In particularly, twisted-cubes, crossed-cubes, and Mobius cubes are all special cases of this construction scheme. Therefore, they are all super fault-tolerant Hamiltonian graphs. (C) 2003 Elsevier Inc. All rights reserved.