Browsing by Issue Date, starting with "2006-12-19"

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Fractal aggregates of conjugated polymer in solution state
(2006-12-19)
Li, Yen-Cheng
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Chen, Kuei-Bai
;
Chen, Hsin-Lung
;
Hsu, Chain-Shu
;
Tsao, Cheng-Si
Semirigid conjugated polymers have received much scientific and technological interest due to their unique electrical and photonic semiconducting properties. Spectroscopic studies have indicated that these polymers underwent interchain aggregation in the solution state even at large dilution; however, the origin of this event and the structure of the resultant aggregates remained the crucial issues to be resolved. In the present study, we revealed that the interchain aggregation of a conjugated polymer, poly(2,3-diphenyl-5-hexyl-1,4-phenylenevinylene) (DP6-PPV), in solutions with chloroform and toluene generated network aggregates with the hydrodynamic radii of several micrometers. Small angle neutron scattering (SANS) demonstrated that the internal structure of these aggregates could be characterized by the mass fractal dimensions of 2.2-2.7. The networks were looser in chloroform but became highly compact in the poorer toluene solvent due to severe segmental association. Increasing the temperature alleviated the segmental association in toluene while largely retaining the mass fractal dimension of the aggregates. However, the interchain aggregation was never completely dissipated by the heating, suggesting the existence of two types of segmental association with distinct stability. The highly stable segmental association that could neither be solvated by chloroform nor be disrupted thermally in toluene was attributed to the d-d complex already present in the DP6-PPV powder used for the solution preparation. The chains tied firmly by this complex formed network aggregates in the solution and hence reduced the entropy of mixing of the polymer. In the poorer toluene solvent, further segmental association took place within the preexisting aggregates, making the networks more compact. This type of segmental association could be disrupted by moderate heating, and its occurrence was ascribed to the poor affinity of the aliphatic side chains of DP6-PPV for toluene.
Thermal stability and electric properties of Ba0.7Sr0.3TiO3 parallel plate capacitor with nano-Cr interlayer
(2006-12-20)
Ho, Chia-Cheng
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Chiou, Bi-Shiou
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Chang, Li-Chun
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Chou, Chen-Chia
;
Liou, Bo-Heng
A novel sandwich structure of Ba0.7Sr0.3TiO3/Cr/Ba0.7Sr0.3TiO3 (BST/Cr/BST) was sputtered onto Pt/Ti/SiO2/Si substrate. With the insertion of a Cr layer, the leakage currents are decreased and the thermal stability of the specimens is enhanced. Temperature coefficient of capacitance (TCC) of specimens with BST(200 nm)/Cr(2 nm)/BST(200 nm) multifilms can achieve about 83% lower than those with BST (400 nm) monolayer. However, the dielectric constant of the BST(200 nm)/Cr(2 nm)/BST(200 nm) multifilms decreases to about 37% of that BST monolayer. The leakage current densities under an electric field of 125 kV/cm at 90 degrees C are 4 x 10(-4) A/cm(2) and 9 x 10(-1) A/cm(2) for BST(200 nm)/Cr(2 nm)/BST(200 nm) and monolayer BST (400 nm), respectively. X-ray diffraction results indicate the formation of a CrO3 secondary phase after annealing at 700 degrees C or above in O-2 atmosphere. The root causes for the improvement of leakage currents and thermal stability with the insertion of nano-Cr interlayer are explored. The results show the insertion of Cr-nanolayer improves the electric properties for application in capacitors. (c) 2006 Elsevier B.V All rights reserved.
監控薄膜厚度變化之方法
(2006-12-21)
趙于飛
;
王夢偉
;
郭俊儀
;
柳克強
;
林滄浪
本發明係揭露一種監控薄膜厚度變化之方法，係用於一相位調變式橢圓儀。此方法包含經由相位調變式橢圓儀及一訊號擷取系統獲得一薄膜之一直流訊號、一一倍頻及一二倍頻訊號，並將前述之訊號傳遞至一電腦裝置。再經由電腦裝置之一如儀控程式之程式以換算前述之訊號得到一橢圓參數。接著，引入橢圓參數以計算薄膜之一厚度週期解，並利用一數據化之一二維厚度表示法即時監控薄膜之厚度週期解的變化。同時，透過程式呈現此方法之一監控畫面於電腦裝置之一顯示單元上。
在網路通道閘道器上提供差別服務之請求排程方法
(2006-12-21)
林盈達
;
曹世強
;
歐陽銘康
;
賴源正
本發明提供一種在網路通道閘道器上提供差別服務之請求排程方法，其係根據「請求封包」的三個參數：反應封包大小、反應封包傳輸時間、反應封包回應延遲，計算出請求封包對應的反應封包在連線網路中所佔用的頻寬，然後透過控制類別中請求封包的送出頻率，以提供公平而且可分享的頻寬，以及在維持高頻寬使用率下，降低接取路徑上發生封包碰撞的可能性。因此本發明可用在企業端網路通道閘道器上進行頻寬管理，以提供使用者間有差別且可分享的服務待遇，並且可以有效降低系統負載。
光交換器監控裝置
(2006-12-21)
祈甡
;
李健仲
;
高大峻
一種光交換器監控裝置，包含：一監控信號產生器、一路徑選擇電路、一監控信號接收器以及一光交換器；主要係藉監控信號產生器中的光延遲模組產生不同時間延遲差之光脈波串列來當作監測信號，而在監控信號接收器中也有一個光延遲模組再次產生不同時間差之光脈波可以用來識別光交換器的光路徑是否有異常，而藉由路徑選擇電路跳過有問題的光路徑，並選擇其他適當光路徑者。
使用者介面產生系統及其方法
(2006-12-21)
陳登吉
;
楊尚庭
;
蔡明志
;
洪啟彰
本發明係揭露一種使用者介面產生系統及其方法，此使用者介面產生系統及其方法係用於手持裝置，本系統至少包含一工作平台、一圖形介面資料庫及一樣板資料庫。圖形介面資料庫係用於產生一預設圖形介面且於工作平台上產生一預設關聯特性，並由樣板資料庫所記錄，形成一使用者介面樣板，再經由工作平台之彙整動作後產生可供手持裝置所使用之一使用者介面程式。此使用者介面產生系統之特色在於使用者介面設計者透過創造使用者介面樣板以設計使用者介面，並可重覆使用而無需程式設計者輔助撰寫程式，降低使用者介面設計者與程式設計者間之漫長溝通。
由金氧半場效電晶體臨界電壓與熱效應電壓所組成之參考電壓電路
(2006-12-21)
洪崇智
本發明係揭露一種由金氧半場效電晶體臨界電壓與熱效應電壓所組成之參考電壓電路。本發明以現有的能隙電壓架構為基礎，並使用了工作於弱反轉層的場效電晶體代替傳統的雙載子電晶體，以產生與溫度係數正相關之電流，再由金氧半場效電晶體臨界電壓產生另一與溫度係數負相關之電流，結合以上兩個電流而產生一不隨溫度變化而改變之穩定參考電流，再將此電流通過一電阻，以產生一與溫度係數完全不相關之參考電壓。
Investigation of void nucleation and propagation during electromigration of flip-chip solder joints using x-ray microscopy
(2006-12-25)
Chiu, S. H.
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Chen, Chih
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材料科學與工程學系
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Department of Materials Science and Engineering
X-ray microscopy was employed to investigate void nucleation and propagation during electromigration in solder joints. The shape of the voids at various stages can be clearly observed. The voids became irregular when they propagated to deplete the contact opening. Growth velocity at the early stage was found to be 1.3 mu m/h under 6.5x10(3) A/cm(2) at 150 degrees C, and it decreased to 0.3 mu m/h at later stages. Formation of intermetallic compound (IMC) and compositional changes at the interface of solder/IMC on the chip side were attributed to the retarded growth rate at later stages. (c) 2006 American Institute of Physics.
Photoluminescence studies of type-II diluted magnetic semiconductor ZnMnTe/ZnSe quantum dots
(2006-12-25)
Kuo, M. C.
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Hsu, J. S.
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Shen, J. L.
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Chiu, K. C.
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Fan, W. C.
Type-II diluted magnetic semiconductor ZnMnTe quantum dots (QDs) in ZnSe matrix grown by molecular beam epitaxy were investigated by conventional and magnetophotoluminescence (PL) spectroscopy. The QD emission exhibits a type-II characteristic in excitation power dependence of PL peak energy. A nonzero circular polarization of PL at the absence of magnetic field was observed. This phenomenon is attributed to the accumulation of interface charges confined in adjacent layers. The magneto-optical measurement demonstrates a magnetic-induced degree of circular polarization in the PL spectra, indicating the Mn incorporation into the QD system. (c) 2006 American Institute of Physics.
Impacts of ammonia background flows on structural and photoluminescence properties of InN dots grown on GaN by flow-rate modulation epitaxy
(2006-12-25)
Ke, W. C.
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Lee, L.
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Chen, C. Y.
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Tsai, W. C.
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Chang, W. -H.
Structural and photoluminescence (PL) properties of InN dots grown on GaN by metal organic vapor phase epitaxy using the flow-rate modulation technique, and their dependence on growth conditions, were investigated. An ammonia (NH3) background flow was intentionally supplied during indium deposition periods to control the kinetics of adatoms and hence the morphology of InN dots. Samples prepared under lower NH3 background flows generally exhibit narrower and more intense PL signals peaked at lower emission energies. The authors point out that the NH3 background flow is an important parameter that controls not only the nucleation process but also the emission property of InN dots. (c) 2006 American Institute of Physics.
A tunable erbium-doped fiber ring laser with power-equalized output
(2006-12-25)
Yeh, Chien-Hung
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Lin, Ming-Ching
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Chi, Sien
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光電工程學系
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Department of Photonics
We propose and demonstrate a tunable erbium-based fiber ring laser with power-equalized output. When a mode-restricting intracavity fiber Fabry-Perot tunable filter (FFP-TF) is combined, the proposed resonator can guarantee a tunable laser oscillation. This proposed laser can obtain the flatter lasing wavelength in an effectively operating range of 1533.3 to 1574.6 nm without any other operating mechanism. Moreover, the performances of the output power, wavelength tuning range, and side-mode suppression ratio (SMSR) were studied. (C) 2006 Optical Society of America.
Tunable slow light device using quantum dot semiconductor laser
(2006-12-25)
Peng, P. C.
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Lin, C. T.
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Kuo, H. C.
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Tsai, W. K.
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Liu, J. N.
This investigation experimentally demonstrates a tunable slow light device using a quantum dot (QD) semiconductor laser. The QD semiconductor laser at 1.3 mu m fabricated on a GaAs substrate is grown by molecular beam epitaxy. Tunable slow light can be achieved by adjusting the bias current and wavelength detuning. The slow light device operated under probe signal from 5 to 10 GHz is presented. Moreover, we also demonstrate that the tunable slow light device can be used in a subcarrier multiplexed system. (C) 2006 Optical Society of America.
Wide-band fiber-optic tunable filter
(2006-12-26)
Chi
;
Sien
;
Chen
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Nan-Kuang
;
Tseng
A wide-band fiber-optic tunable filter is provided. Dispersive polymers with different dispersion characteristics and side-polished fibers are used to fabricate wide-band tunable band-pass filters, band-rejection filters, short-wavelength-pass filters or long-wavelength-pass filters. This kind of wide-band fiber-optic tunable fiber filters is able to be used in the applications of fiber-to-the-home (FTTH) system networks. It is also able to be used in the applications of sensitive temperature sensors, high-resolution fiber refractometers, gain-flattened filters, fiber modal filters and fiber mode-field expanders/condensers.
Syntheses and the study of strongly hydrogen-bonded poly(vinylphenol-b-vinylpyridine) diblock copolymer through anionic polymerization
(2006-12-26)
Kuo, Shiao-Wei
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Tung, Pao-Hsiang
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Chang, Feng-Chih
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應用化學系
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Department of Applied Chemistry
A series of poly(vinylphenol-b-vinylpyridine) (PVPh-b-P4VP) block copolymers were prepared through anionic polymerizations of 4-tert-butoxystyrene with 4-vinylpyridine followed by subsequent selective hydrolysis of the 4-tert-butoxystyrene protective groups. Infrared spectrum analysis suggests that this block copolymer possesses strong hydrogen-bonding interaction between the hydroxyl group of PVPh and the pyridine group of P4VP. DSC analyses indicate that these PVPh-b-P4VP copolymers always have higher glass transition temperatures than the corresponding PVPh/P4VP miscible blends obtained from DMF solution. However, the thermal behavior of PVPh-b-P4VP diblock copolymer shows a similar T-g value with the PVPh/P4VP blend complex obtained from methanol solution at a 1:1 (PVPh:P4VP) molar ratio. We proposed that the polymer chain behavior of the PVPh/P4VP blend from DMF solution is separated coils. However, by increasing the hydrogen bonding for PVPh-b-P4VP diblock copolymer, a polymer complex aggregate is proposed, which is similar to the PVPh/P4VP blend complex from methanol solution. The spin-lattice relaxation time in the rotating frame (T-1 rho(H)) based on solid-state NMR analysis is able to provide positive evidence that the polymer complex aggregate in the diblock copolymer has a shorter T-1 rho(H) value than the separated coils in the miscible blend.
alpha-labeling number of trees
(2006-12-28)
Shiue, Chin-Lin
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Fu, Hung-Lin
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應用數學系
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Department of Applied Mathematics
In this paper, we prove that the alpha-labeling number of trees T, T-alpha <= [r/2] n where n = vertical bar E(T)vertical bar and r is the radius of T. This improves the known result T-alpha <= e(O(root nlogn)) tremendously and this upper bound is very close to the upper bound T-alpha <= n conjectured by Snevily. Moreover, we prove that a tree with n edges and radius r decomposes K-1 for some t <= (r + 1)n(2) + 1. (c) 2006 Elsevier B.V. All rights reserved.
Cu-metalized compound semiconductor device
(2006-12-28)
Chang, Edward Yi
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Chang, Shang-Wen
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Lee, Cheng-Shih
The present invention is a compound semiconductor device characterized in that it is Cu-metalized to improved the reliability of the device and to greatly reduce the cost of production.
Influence of the threading dislocations on the electrical properties in epitaxial ZnO thin films
(2006-12-29)
Liu, W. -R.
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Hsieh, W. F.
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Hsu, C. -H.
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Liang, K. S.
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Chien, F. S. -S.
The structural and electrical properties of epitaxial ZnO films grown by pulsed-laser deposition on sapphire (0001) were investigated by high-resolution X-ray diffraction (XRD), atomic force microscopy (AFM), scanning capacitance microscopy (SCM), conductive atomic force microscopy (C-AFM), and transmission electron microscopy (TEM). The results of XRD and AFM revealed that the ZnO films have a columnar-grain structure consisting of epitaxial cores surrounded by annular boundaries. The core and boundary regions exhibited significantly different capacitive responses and field emission current. The results of TEM indicated that the annular boundaries have high-density edge threading dislocations. The shift of flatband voltage and the raise of potential barrier at the boundaries observed by SCM and C-AFM were attributed to the interface trap densities caused by the existence of high-density edge threading dislocations. (c) 2006 Elsevier B.V. All rights reserved.
Effects of hole injection layer thickness on the luminescent properties of white organic light-emitting diodes
(2006-12-30)
Li, Jian-Feng
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Chen, Shih-Fang
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Su, Shui-Hsiang
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Hwang, Kao-Shing
;
Yokoyama, Meiso
This work investigates how the thickness of the hole injection layer (HIL) influences the luminescent characteristics of white organic light-emitting diodes (WOLED). Experimental results indicate that inserting a thin HIL (< 200 angstrom) into a WOLED without an HIL reduces the brightness and clearly changes the chromaticity because the surface of the 4,4',4"-tris{N,-(3-methylphenyl)-N-phenylamino}-triphenylamine) (m-MTDATA) film is extremely rough. In contrast, a dense film structure and the fine surface morphology of m-MTDATA of moderate thickness (350-650 angstrom) provides a uniform conducting path on which holes cross the indium tin oxide (ITO)/HIL interface, improving luminescent performance, associated with the relatively stable purity of the color of the emission, with Commission Internationale 1'Eclairage (CIE) coordinates of (x = 0.40, y = 0.40). However, inserting a thick HIL (> 650 angstrom) reduces the luminescent performance and causes red-shift, because the holes and electrons in the effective emissive confinement region become less optimally balanced. Moreover, optimizing the device structure enables a bright WOLED with CIE coordinates of (x = 0.34, y = 0.33) to reach a luminance of 7685 cd/m(2) at a current density of 100 mA/cm(2), with a maximum luminous efficiency of 1.72 Im/W at 5.5 V. (c) 2006 Elsevier B.V. All rights reserved.
For our sister Xiou Qin
(Routledge, 2007)
J. Ho
Regulatory knowledge management for semiconductor manufacturing in China
(2007)
Trappey, Charles V.
;
Tseng, Ai-Hua
;
管理科學系
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Department of Management Science
There is a growing need to create trade data and regulatory information systems for manufacturers building new facilities in emerging world markets. These multinational companies must track world trade organization (WTO) rules as well as the domestic rules of operation. A semiconductor manufacturer must carefully monitor and take quick action on regulatory matters. The need for trade and market information and systems is now an integral part of global manufacturing. Without systems to monitor and process the every changing flow of rules and regulations, managers and engineers are less effective in preventing violations or arguing for changes. After China's accession to WTO, there has been remarkable growth in domestic regulations for the manufacture of electronic goods. Likewise, since electronic goods and components are of strategic importance to many of the worlds leading manufacturers, the rule base has become a multi-lingual and evolving collection that is extremely difficult to monitor or even effectively report about. The objective of this research is to study the management of a sub-set of the trade related data and develop a prototype information system for processing and managing trade regulations. A case analysis of the application in industry is provided.