Browsing by Issue Date, starting with "2004-12-01"

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低溫多晶矽薄膜電晶體主動層之雷射再結晶方法
(2004-12-01)
葉清發
;
陳添富
;
羅正忠
本發明係一種低溫多晶矽薄膜電晶體主動層之雷射再結晶方法，其係利用具單一方向性之乾式蝕刻在薄膜電晶體主動層側壁覆蓋一間距矽(poly–spacer)，該間距矽(poly–spacer)提供了一雷射側向再結晶機制與可防止雷射再結晶後主動層微縮或剝落現象，可使通道內之矽晶粒變大但不需額外光罩，如此同時提升元件特性、提高元件均勻度與節省製程成本，此技術在現今低溫多晶矽薄膜電晶體(LTPS–TFTs)領域中將會是一項關鍵技術。
An optimal interpolated FIR echo canceller for digital subscriber lines
(2004-12-01)
Lin, SS
;
Wu, WR
;
電信工程研究所
;
Institute of Communications Engineering
An adaptive interpolated FIR (IFIR) echo canceller was recently proposed for xDSL applications. This canceller consists of an FIR filter, an IFIR filter, and a tap-weight overlapping and nulling scheme. The FIR filter is used to cancel the short and rapidly changing head echo while the IFIR filter is used to cancel the long and slowly decaying tail echo. This echo canceller, which inherits the stable characteristics of the conventional FIR filter, requires low computational complexity. It is well known that the interpolation filter for an IFIR filter has great influence on the interpolated result. In this paper, a least-squares method is proposed to obtain optimal interpolation filters such that the performance of the IFIR echo canceller can be further improved. Simulations with a wide variety of loop topologies show that the optimal IFIR echo canceller can effectively cancel the echo up to 73.0 dB (for an SHDSL system). About 57% complexity reduction can be achieved compared to a conventional FIR filter.
Diagnosability of t-connected networks and product networks under the comparison diagnosis model
(2004-12-01)
Chang, CP
;
Lai, PL
;
Tan, JJM
;
Hsu, LH
;
資訊工程學系
Diagnosability is an important factor in measuring the reliability of an interconnection network, while the (node) connectivity is used to measure the fault tolerance of an interconnection network. We observe that there is a close relationship between the connectivity and the diagnosability. According to our results, a t-regular and t-connected network with at least 2t + 3 nodes is t-diagnosable. Furthermore, the diagnosability of the product networks is also investigated in this work. The product networks, including hypercube, mesh, and tori, comprise very important classes of interconnection networks. Herein, different combinations of t-diagnosable and t-connected are employed to study the diagnosability of the product networks.
Single mode 1.3 mu m InGaAsN/GaAs quantum well vertical cavity surface emitting lasers grown by molecular beam epitaxy
(2004-12-01)
Hsiao, RS
;
Wang, JS
;
Lin, KF
;
Wei, L
;
Liu, HY
The growth by molecular-beam-epitaxy of high-quality 1.3 mum InGaAsN/GaAs quantum wells (QW) intra-cavity contacted vertical cavity surface emitting lasers (VCSELs) was demonstrated. Low-temperature growth, which suppresses the phase separation significantly improves material quality in the active region. Room-temperature continuous wave (RT-CW) single mode output power of 0.75 mW with an initial slope efficiency of 0.17 W/A and a side mode suppression ratio of 40 dB at a lasing wavelength of as long as 1304 nm were obtained.
A resolvable r x c grid-block packing and its application to DNA library screening
(2004-12-01)
Mutoh, Y
;
Jimbo, M
;
Fu, HL
;
應用數學系
;
Department of Applied Mathematics
For a nu-set V, let A be a collection of r x c arrays with elements in V. A pair (V, A) is called an r x c grid-block packing if every two distinct points i and j in V occur together at most once in the same row or in the same column of arrays in A. And an r x c grid-block packing (V, A) is said to be resolvable if the collection of arrays A can be partitioned into sub-classes R-1, R-2,..., R-t such that every point of V is contained in precisely one array of each class. These packings have originated from the use of DNA library screening. In this paper, we give some constructions of resolvable r x c grid-block packings and give a brief survey of their application to DNA library screening.
Nanoparticles of Pb-Bi eutectic nucleation and growth on alumina template
(2004-12-01)
Chen, CC
;
Kuo, CG
;
Chen, JH
;
Chao, CG
;
材料科學與工程學系
A novel and convenient method of thermo-immersion was used to fabricate of a large of lead-bismuth (Pb-Bi) eutectic nanoparticles on an uniform size anodic aluminum oxide (AAO) template. The AAO with a 60 nm pore diameter was used as a template for nanoparticles nucleation and growth. Both Pb-Bi and AAO were placed in a glass tube in vacuum at 10(-6) Torr, controlled by a molecular turbo pump then heated up to the melting point of the alloy. Nanoparticles nucleated and grew on the AAO template when the molten Pb-Bi solidified. The nanoparticles nucleated on the pore corners of the AAO template initially, grew simultaneously and assembled into a big nanoparticle on top of the AAO template later. Additionally, the size diameters of the initial nanoparticles were approximately 15 nm on the pore corners of the AAO template, and 80 nm when the initial nanoparticles formed a large nanoparticle. Latent heat was released when the molten Pb-Bi solidified to form nanoparticles. The size diameters distribution of nanoparticles was observed by scanning electron microscopy (SEM) such that, the diameters of the nanoparticles were 80 nm on top of the AAO template, and 200 nm in depths of the concave.
Improving spin-coating process using altered cover design
(2004-12-01)
Cheng, CM
;
Chen, RH
;
機械工程學系
;
Department of Mechanical Engineering
A novel work chamber cover design for a spin coater that can reduce the effect of airflow on spin coating is presented. The experimental results reveal that superior uniformity and film area can be obtained by utilizing the modified design instead of the conventional design.
Growth of ZnO nanowires without catalyst on porous silicon
(2004-12-01)
Chang, CC
;
Chang, CS
;
光電工程學系
;
Department of Photonics
Porous silicon (PS) technology is, for the first time, used to grow ZnO nanowires on the surface of a PS substrate with a rough morphology without any catalyst. The characteristics of these nanowires were investigated by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), grazing-angle X-ray diffraction (XRD) and photoluminescence (PL) measurements. Zn vapor condenses easily on the PS surface and forms a wetting layer, but not on the flat Si surface. The PS surface provides a rough surface morphology to form a wetting layer by decreasing the surface energy so that ZnO nanowires can grow without any catalyst. The Zn-rich composition changed during growth; the ratio of zinc to oxygen was near to one at the top part of the nanowires. The probable growth mechanism was the vapor-solid (VS) process. In principle, the selective growth of ZnO nanowires on Si-base devices for optoelectronic application is possible.
Chaos anticontrol and synchronization of three time scales brushless DC motor system
(2004-12-01)
Ge, ZM
;
Cheng, JW
;
Chen, YS
;
機械工程學系
;
Department of Mechanical Engineering
Chaos anticontrol of three time scale brushless dc motors and chaos synchronization of different order systems are studied. Nondimensional dynamic equations of three time scale brushless DC motor system are presented. Using numerical results, such as phase diagram, bifurcation diagram, and Lyapunov exponent, periodic and chaotic motions can be observed. By adding constant term, periodic square wave, the periodic triangle wave, the periodic sawtooth wave, and kxx term, to achieve anticontrol of chaotic or periodic systems, it is found that more chaotic phenomena of the system can be observed. Then, by coupled terms and linearization of error dynamics, we obtain the partial synchronization of two different order systems, i.e. brushless DC motor system and rate gyroscope system. (C) 2004 Elsevier Ltd. All rights reserved.
Oxidation of TNT by photo-Fenton process
(2004-12-01)
Liou, MJ
;
Lu, MC
;
Chen, JN
;
環境工程研究所
;
Institute of Environmental Engineering
A series of photo-Fenton reactions have been performed for the degradation of 2,4,6-trinitrotoluene (TNT) in a 4.2-1 reactor. The degradation reaction rate of TNT followed a pseudo-first-order behavior; and the rate constants for 2.4 mW cm(-2) UV only, 2.4 mWcm(-2)UV/H2O2, Fenton, photo-Fenton (2.4 mW cm(-2)) and photo-Fenton (4.7 mW cm(-2)) were 0.002 min(-1), 0.007 min(-1), 0.014 min(-1), 0.025 min(-1) and 0.037 min(-1), respectively. Increasing the intensity of UV light, and the concentrations of ferrous ions and hydrogen peroxide promoted the oxidation rate under the experimental conditions in this study. The weighting factor (f), the Fe(II)-promoted efficiency (r) and the promoted-UV light efficiency (p) were calculated to clarify their effects on the TNT oxidation. Moreover, the inhibition effect of hydroxyl radical was also observed in both Fenton and photo-Fenton oxidation when the concentration of Fe(II) were higher than 2.88 mM. Solid phase micro-extraction was first applied to the separation of the organic byproducts from TNT oxidation. GC/MS was employed to identify the byproducts during the Fenton and photo-Fenton oxidation of TNT. These compounds were clarified as 1,3,5-trinitrobenzene, 1-methyl-2,4-dinitrobenzene 2,5-dinitrobenzoic acid and 1,3-dinitrobenzene. By these byproducts, the mechanisms of the methyl group oxidation, decarboxylation, aromatic ring breakage, and hydrolysis can be recognized and demonstrated. The pathway of TNT oxidation by photo-Fenton process was also proposed in this study. (C) 2004 Elsevier Ltd. All rights reserved.
0.13-mu m RF CMOS and varactors performance optimization by multiple gate layouts
(2004-12-01)
Ho, CC
;
Kuo, CW
;
Chan, Y
;
Lien, WY
;
Guo, JC
0.13-mum radio frequency (RF) CMOS devices with multifinger gate structure have been fabricated by the standard logic process, and the measured effective gate-length is 80 nm. Extensive RF characterization has been done to obtain cutoff frequency (f(T)), associated power gain cutoff frequency (f), minimum noise figure (NFmin), output power (P-out), and power added efficiency (PAE) for RF circuit design and to explore the optimized gate layout in terms of the extracted RF device parameters. Our important finding to be reported in this paper is that an optimized unit finger width (W-F) exists by trade-off among f(T), f(.max), NFmin, P-out, and PAE. Under fixed total width to achieve the same current drivability (I-ds), the smaller W-F and the larger finger number (N-F) leads to higher f(max) but lower f(T) due to trade-off between gate resistance (R-g) and parasitic gate capacitance. As for NFmin complicated by f(T) and R-g, counter-balance between parasitic gate capacitance and R-g leads to nearly constant NFmin. w.r.t. various splits of (W-F, N-F). Regarding P-out and PAE, W-F of 4 mum and NF of 18 is the optimized layout parameter, which offers the maximum P-out of around 11 dBm and PAE of 30.5% at 5.8 GHz. The performances of accumulation-mode MOS varactors with different gate layout structures are also investigated in this report. Since the same area varactors with different gate layout may result in different parasitic resistance and fringing capacitance, which will affect the capacitance tuning range and the associated Q-factor. The maximum Q-factor is about 59 of the 120 mum(2) gate area varactor, and its tuning range is from 210 IF to 1.64 pF, where the maximum C-max/C-min ratio is about 7.8.
Dynamic encoder/decoder based on fiber Bragg gratings for optical security system
(2004-12-01)
Peng, PC
;
Peng, WR
;
Lin, WP
;
Chi, S
;
光電工程學系
A novel dynamic encoder/decoder based on fiber Bragg gratings for optical security systems is presented in this paper. The encoded and decoded optical communication signals can be realized by controlling the optical switches and fiber Bragg grating arrangement. We describe the system operation principle and set up an experimental encoder/decoder to demonstrate the feasibility of the proposed scheme.
Treating high-turbidity water using full-scale floc blanket clarifiers
(2004-12-01)
Lin, WW
;
Sung, SS
;
Chen, LC
;
Chung, HY
;
Wang, CC
Dynamic responses of the blanket in full-scale flat-bottom type floe blanket clarifiers at the PingTsan Water Works, Taiwan Water Supply Corporation, were monitored given a step-change in coagulant (polyaluminum chloride, PACl) dosage. The blankets in the clarifiers were easily washed out using the conventional coagulation-clarification process (the "single-stage process"), seriously threatening drinking water quality. Consequently, the PingTsan Water Works included a pretreatment stage before the single-stage process to enhance treatment efficiency. The performance of this full-scale "two-stage process" for treating high-turbidity storm water was monitored on November 9 to 10, 2000. The two-stage process achieved a stable blanket and good quality clarified water that was insensitive to variation in raw water turbidity or PACl dose. Pilot tests were also conducted on October 6 to 7, 2001 to reveal performance differences between the single-stage and two-stage processes in dealing with high-turbidity water. The single-stage process yielded a blanket that was sensitive to PACl change. Not only was the produced blanket easily washed out when the PACl dose was step-decreased, it was also slow to recover when the chemical dosage was returned to its original value. The blanket yielded by the two-stage process was more robust to low coagulant dose, and recovered more easily when coagulant supply was increased. Applying the two-stage process to achieve the same effluent quality from single-stage process could significantly reduce total PACl dosage.
Facilitating changes in ninth grade students' understanding of dissolution and diffusion through DSLM instruction
(2004-12-01)
She, HC
;
教育研究所
;
Institute of Education
This study examines the nature and process of ninth grade students' conceptual change regarding their mental model of dissolution and diffusion as a result of instructions using the Dual Situated Learning Model (DSLM). The dual situated learning events of this model are designed according to the students' ontological viewpoint of the science concepts as well as the nature of these cancepts. Moreover, these events serve two functions by creating dissonance with the pre-existing knowledge and providing new schema for constructing a more scientific view of the concept. The concepts of dissolution and diffusion were chosen to examine students' conceptual change process bemuse they involve the understanding of both invisible and process attributes. Results indicate that about 76%-90% of the students successfully underwent a change in their understanding of the cones of dissolution and diffusion after instruction using dual situated learning events. Moreover, about 75%, of the students successfully applied their previous mental sets into the challenging situated learning event. This current study demonstrates that DSLM indeed facilitates the processes of conceptual change and knowledge acquisition involving concepts of dissolution and diffusion, clarifying the nature of conceptual change involving science concepts of both an invisible and a process nature.
Alignment and orientation of absorbed dipole molecules
(2004-12-01)
Liao, YY
;
Chen, YN
;
Chuu, DS
;
電子物理學系
;
Department of Electrophysics
Half-cycle laser pulse is applied on an absorbed molecule to investigate its alignment and orientation behavior. Crossover from field-free to hindered rotation motion is observed by varying the angel of hindrance of potential well. At small hindered angle, both alignment and orientation show sinusoidal-like behavior because of the suppression of higher excited states. However, mean orientation decreases monotonically as the hindered angle is increased, while mean alignment displays a minimum point at certain hindered angle. The reason is attributed to the symmetry of wave function and can be explained well by analyzing the coefficients of eigenstates.
Quantum correlations in bound-soliton pairs and trains in fiber lasers
(2004-12-01)
Lee, RK
;
Lai, Y
;
Malomed, BA
;
光電工程學系
;
光電工程研究所
Quantum correlations in pairs and arrays (trains) of bound solitons modeled by the complex Ginzburg-Landau equation (CGLE) are calculated numerically, on the basis of linearized equations for quantum fluctuations. We find strong correlations between the bound solitons, even though the system is dissipative. Some degree of the correlation between the photon-number fluctuations of stable bound soliton pairs and trains is attained and saturates after passing a certain distance. The saturation of the photon-number correlations is explained by the action of nonconservative terms in the CGLE. Photon-number-correlated bound soliton trains offer possibilities to produce multipartite entangled sources for quantum communication and computation.
Relationship between local structural entropy and protein thermostability
(2004-12-01)
Chan, CH
;
Liang, HK
;
Hsiao, NW
;
Ko, MT
;
Lyu, PC
We developed a technique to compute structural entropy directly from protein sequences. We explored the possibility of using structural entropy to identify residues involved in thermal stabilization of various protein families. Examples include methanococcal adenylate kinase, Ribonuclease HI and holocytochrome c(551). Our results show that the positions of the largest structural entropy differences between wild type and mutant usually coincide with the residues relevant to thermostability. We also observed a good linear relationship between the average structural entropy and the melting temperatures for adenylate kinase and its chimeric constructs. To validate this linear relationship, we compiled a large dataset comprised of 1153 sequences and found that most protein families still display similar linear relationships. Our results suggest that the multitude of interactions involved in thermal stabilization may be generalized into the tendency of proteins to maintain local structural conservation. The linear relationship between structural entropy and protein thermostability should be useful in the study of protein thermal stabilization. (C) 2004 Wiley-Liss, Inc.
在玻璃基板上製作單晶矽薄膜電晶體之方法
(2004-12-01)
葉清發
;
陳添富
;
羅正忠
本發明係一種在玻璃基板上製作單晶矽薄膜電晶體之方法，其係利用具單一晶格方向的矽基板作為晶種以觸發非晶矽薄膜側向成長單晶矽薄膜的方法，作法為將非晶矽薄膜與有圖案之單晶矽基板面對面接觸後，利用準分子雷射從背面穿透玻璃基板使正面的非晶矽薄膜得以單晶矽基板上之圖案為晶種側向成長單晶矽薄膜，如此便可進一步在玻璃基板上製作單晶矽的薄膜電晶體，作為晶種的矽基板經過簡單處理後就可重複使用，在量產上並不會增加太多的製造成本，並具有較高的載子移動率與較好的元件均勻性及可靠度。
Note on inventory model with a mixture of back orders and lost sales
(2004-12-01)
Chu, P
;
Yang, KL
;
Liang, SK
;
Niu, T
;
工業工程與管理學系
Competitiveness is an important means of determining whether a company will prosper. Business organizations compete with one another in a variety of ways. Among these competitive methods are time and cost factors. The purpose of this paper is to examine the inventory models presented by Padmanabhan and Vrat [International Journal of Systems Sciences 21 (1990) 1721] with a mixture of back orders and lost sales. We develop the criterion for the optimal solution for the total cost function. If the criterion is not satisfied, this model will degenerate into one cycle inventory model with a finite inventory period. This implies an extension of shortage period as long as possible to produce lower cost. However, we know that time is another important factor in company competitiveness. Customers will not indefinitely wait for back orders. A tradeoff will be made between the two most important factors; time and cost. The minimum total cost is evaluated under the diversity cycle time and illustrations are applied to explain the calculation process. This work provides a reference for decision-makers. (C) 2003 Elsevier B.V. All rights reserved.
On multiple-voltage high-level synthesis using algorithmic transformations
(2004-12-01)
Dung, LR
;
Yang, HC
;
電控工程研究所
;
Institute of Electrical and Control Engineering
This paper presents a multiple-voltage high-level synthesis approach for low power DSP applications using algorithmic transformation techniques. Our approach is motivated by maximization of task mobilities in that the increase of mobilities may raise the possibility of assigning tasks to low-voltage components. The mobility means the ability to schedule the starting time of a task. It is defined as the distance between its as-late-as-possible (ALAP) schedule time and its as-soon-as-possible (ASAP) schedule time. To earn task mobilities, we use loop shrinking, retiming and unfolding techniques. The loop shrinking can first reduce the iteration period bound (IPB) and, then, the others are employed for shortening the iteration period (IP) as much as possible. The minimization of IP results in high task mobilities. Finally, we can assign tasks with high mobilities to low-voltage components and, thus, minimize energy under resource and latency constraints. With considering the overhead of level conversion, our approach can achieve significant power reduction. In the case of the third-order IIR filter, the proposed approach can save up to 40.2% of power consumption.