Browsing by Author "Chen, WC"

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A data mining project for solving low-yield situations of semiconductor manufacturing
(2004)
Chen, WC
;
Tseng, SS
;
Hsiao, KR
;
Liu, CC
;
資訊工程學系
With huge amount of semiconductor engineering data stored in database and versatile analytical charting and reporting in production and development, the CIM/MES/EDA systems in the most semiconductor manufacturing companies help users to analyze the collected data in order to achieve the goal of yield enhancement. However, the procedures of semiconductor manufacturing are sophisticated and the collected data among these procedures are thus becoming high-dimensional and huge. Currently, some statistical methods, such like K-W test, covariance analysis, regression analysis, etc., have been used to analyze the information summarized from EDA system, and thus generate too many indexes that can not be easily judged and assimilated by engineers. Besides, too many false alarms may be raised and lots of time is required to check the factuality among them. In order to deal with the large amount and high-dimensional data, the data mining technologies are thus used to solve such problems. In this paper, we would like to propose a data mining solution and describe the experiences applying such solutions for discovering the root causes of low-yield situations in a worldwide semiconductor manufacturing company. Also, the situation of applying such mining solution for manufacturing defects detection in semiconductor manufacturing domain will be reviewed Finally, the architecture of a reasonable, reliable and flexible data mining system will be briefly described.
A framework of features selection for the case-based reasoning
(2000)
Chen, WC
;
Tseng, SS
;
Chen, JH
;
Jiang, MF
;
資訊工程學系
CBR is a problem solving technique that reuses past cases and experiences to find a solution to the problems. A critical issue in case-based reasoning is to select the correct and enough features to represent a case. For this reason, the analysis of cases and extraction the necessary features to represent a case are highly recommended in building a CBR system. However, this task is difficult to carry out since such knowledge often cannot be successfully and exhaustively captured and represented. In this paper, a framework of features mining system for the case-based reasoning including two phases has been proposed. The techniques of features selection, data analysis and machine learning can thus be effectively integrated. This will promote flexibility and expandability of case-based reasoning system.
A novel manufacturing defect detection method using association rule mining techniques
(2005-11-01)
Chen, WC
;
Tseng, SS
;
Wang, CY
;
資訊工程學系
;
Department of Computer Science
In recent years, manufacturing processes have become more and more complex, and meeting high-yield target expectations and quickly identifying root-cause machinesets, the most likely sources of defective products, also become essential issues. In this paper, we first define the root-cause machineset identification problem of analyzing correlations between combinations of machines and the defective products. We then propose the Root-cause Machine Identifier (RMI) method using the technique of association rule mining to solve the problem efficiently and effectively. The experimental results of real datasets show that the actual root-cause machinesets are almost ranked in the top 10 by the proposed RMI method. (c) 2005 Elsevier Ltd. All rights reserved.
A novel manufacturing defect detection method using data mining approach
(2004)
Chen, WC
;
Tseng, SS
;
Wang, CY
;
資訊工程學系
;
Department of Computer Science
In recent years, the procedure of manufacturing has become more and more complex. In order to meet high expectation on quality target, quick identification of root cause that makes defects is an essential issue. In this paper, we will refer to a typical algorithm of mining association rules and propose a novel interestingness measurement to provide an effective and accurate solution. First, the manufacturing defect detection problem of analyzing the correlation between combinations of machines and the result of defect is defined. Then, we propose an integrated processing procedure RMI (Root cause Machine Identifier) to discover the root cause in this problem. Finally, the results of experiments show the accuracy and efficiency of RMI are both well with real manufacturing cases.
A parallelized indexing method for large-scale case-based reasoning
(2002-08-01)
Chen, WC
;
Tseng, SS
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Chang, LP
;
Hong, TP
;
Jiang, MF
Case-based reasoning (CBR) is a problem-solving methodology commonly seen in artificial intelligence. It can correctly take advantage of the situations and methods in former cases to find out suitable solutions for new problems. CBR must accurately retrieve similar prior cases for getting a good performance. In the past, many researchers proposed useful technologies to handle this problem. However, the performance of retrieving similar cases may be greatly influenced by the number of cases. In this paper, the performance issue of large-scale CBR is discussed and a parallelized indexing architecture is then proposed for efficiently retrieving similar cases in large-scale CBR. Several algorithms for implementing the proposed architecture are also described. Some experiments are made and the results show the efficiency of the proposed method. (C) 2002 Elsevier Science Ltd. All rights reserved.
An expert system for object-oriented program testing
(1998)
Chen, WC
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Chen, DJ
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Chen, DTK
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資訊科學與工程研究所
;
Institute of Computer Science and Engineering
Data abstraction, information hiding, inheritance, and dynamic binding are four basic elements used in designing object-oriented (OO) programs. These four mechanisms enable programmer to write OO programs for easy to be extended, easy to be reused, and easy to be maintained. Software implemented by OO methodologies had been shown to be able to increase software quality and productivity [5]. However, the quality and reliability of the software cannot be guaranteed along without an appropriate software testing approach. Traditional testing approaches cannot be applied directly for the testing of OO programs due to the OO characteristics used in OO programs. In this paper we propose and implement an expert system for the testing of OO programs. The proposed testing framework contains a system model and OO testing strategies. Rules used to represent these proposed testing strategies are discussed and formulated. Exampling tested programs are provided to demonstrate the applicability of the proposed approach.
An expert-system technique for object-oriented program testing
(1999-02-01)
Chen, WC
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Chen, DJ
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Chung, CG
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資訊科學與工程研究所
;
Institute of Computer Science and Engineering
Data abstraction, information hiding, inheritance, and dynamic binding are four basic elements used in designing object-oriented (OO) programs. These four mechanisms enable programmers to write object-oriented programs that are easily extended, reused and maintained. Software implemented by OO methodologies has increased software quality and productivity.(1) However, this cannot be guaranteed without an appropriate software testing approach. Traditional testing approaches cannot be applied directly to the testing of OO programs due to the OO characteristics used in these programs. OO program testing strategies and methods are proposed continually, but fewer OO testing tools with flexibility are discussed.
Business agent
(2002)
Meng, IH
;
Yang, WP
;
Chen, WC
;
Chang, LP
;
資訊工程學系
The Internet and World Wide Web represent an increasingly important channel for retail commerce as well as business transactions. However, there are almost 5 billion pages or sites on the Internet and WWW. There lacks an integrated mediator business agent which is around the internet to connect between suppliers and users. Therefore, an intelligent business broking agent between supply and demand is needed for using and sharing the information efficiently and effectively. In this paper we proposed a new business agent architecture. The Business Spy Agent (BSA) captures the supply and demand information from e-commence sites automatically. Supply and Demand Analysis Mechanism (SDAM) uses NLP technologies to extract product and trading information. Domain ontology is used to classify between supply and demand and to divide them into subsets. A benefit model is proposed to handle the pairing between sub-supply and sub-demand. And a divide-and-conquer algorithm is proposed to handle the whole matching between supply and demand. In the negotiation process, the architecture uses NLP and template to produce negotiation text to handle negotiation through mail. Finally, Hidden Business Mining Mechanism (HBMM) adopts data mining technology to achieve hidden business mining. The architecture covers the four process of buying behavior including support and need identification, Product brokering, Merchant brokering, Negotiation.
Detecting intrusion patterns using bit-wise indexing method
(2001)
Chen, WC
;
Tseng, SS
;
Ou, CH
;
資訊工程學系
;
Department of Computer Science
Although there are many available computer security methods (like Identification and authentication (I&A), Access Control and Firewalls), the computer security is still a big problem today due to the network protocol and operating system flaws and the variances of intrusions. Building an intrusion detection system has become one of the most important topics in the computer security domain. In order to identify the intrusion behavior, the expression of intrusion patterns becomes a very important issue for a success intrusion detection system. In this paper, we propose a new, efficient and service-oriented intrusion pattern mining and representation method, called Bit-wise-based Intrusion Pattern Mining Method (BIPAM), which can provide higher performance, better maintenance and expressive abilities. These bit-wised-based patterns can be the description of intrusion behaviors of the online intrusion detection systems and thus enhance the efficiency and extendibility of such systems.
Effect of rapid thermal annealing on carrier lifetimes of arsenic-ion-implanted GaAs
(1996-08-12)
Lin, GR
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Chen, WC
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Ganikhanov, F
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Chang, CS
;
Pan, CL
Femtosecond time-resolved reflectivity measurements, structural, and electrical analyses have been performed to investigate the effect of rapid thermal annealing (RTA) on GaAs implanted with 200 keV arsenic ions at 10(16) ions/cm(2). Ultrashort carrier lifetimes from 0.48 fs to 2.3 ps were observed for samples annealed at temperatures between 600 and 800 degrees C. The time constants are somewhat shorter than those of RTA-annealed low-temperature molecular-beam epitaxy grown material, while following the same trend of longer time constants and recovery of resistance at higher annealing temperatures. Arsenic precipitates were not observed. (C) 1996 American Institute of Physics.
Effect of thermal annealing on electrical conductivities in arsenic-ion-implanted GaAs
(1996-01-29)
Chen, WC
;
Chang, CS
;
交大名義發表
;
光電工程學系
;
National Chiao Tung University
The effect of thermal annealing on the electrical conductivities of arsenic-ion-implanted GaAs has been investigated by deep level transient spectroscopy and temperature-dependent conductance measurements. For the annealed films of arsenic-ion-implanted GaAs a band of deep-level defects with the activation energy of around 0.55 eV below the conduction band is found. The dense concentration of traps is able to reduce the carrier concentration from 3 X 10(18) to 2 X 10(17) cm(-3). The cross section of the deep level is calculated to be 1.5 X 10(-14) cm(2). The carrier-transport mechanisms of both as-implanted GaAs and postannealed GaAs are dominantly shown to be a separate hopping and active-type conduction. (C) 1996 American Institute of Physics.
Effects of doping concentration and annealing temperature on properties of highly-oriented al-doped ZnO films
(2006-01-18)
Kuo, SY
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Chen, WC
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Lai, FI
;
Cheng, CP
;
Kuo, HC
Transparent and conductive high-preferential c-axis-oriented Al-doped zinc oxide (ZnO:Al, AZO) thin films have been prepared by the sol-gel route. Film deposition was performed by spin-coating technique on Si(1 0 0) and glass substrate. Structural, electrical and optical properties were performed by XRD, SEM, four-point probe, photoluminescence (PL) and UV-VIS spectrum measurements. The effects of annealing temperature and dopant concentration on the structural and optical properties are well discussed. It was found that both annealing temperature and doping concentration alter the microstructures of AZO films. Also, PL spectra show two main peaks centered at about 380 nm (UV) and 520 nm (green). The variation of UV-to-green band emission was greatly influenced by annealing temperatures and doping concentration. Reduction in intensity ratio of UV-to-green might possibly originate from the formation of Al-O bonds and localized Al-impurity states. The minimum sheet resistance of 10(4)ohm/rectangle was obtained for the film doped with 1.6mol% Al, annealed at 750 degrees C. Meanwhile, all AZO films deposited on glass are very transparent, between 80% and 95% transmittance, within the visible wavelength region. These results imply that the doping concentration did not have significant influence on transparent properties, but improve the electrical conductivity and diversify emission features. (c) 2005 Elsevier B.V. All rights reserved.
Electrical properties in arsenic-ion-implanted GaAs
(1996-08-01)
Chen, WC
;
Chang, CS
;
光電工程研究所
;
Institute of EO Enginerring
A model of effective surface potential energy is proposed to explain unknown behavior of carrier transport in film and leakage currents in Schottky diodes. X-ray photoelectron spectroscopy is employed to investigate a series of band diagrams of arsenic-ion-implanted GaAs films. It is shown that the effective surface potential energies, affected by the shift of core levels, are due to different microstructures and atomic environments in these films at different annealing temperatures. Moreover, the effective barrier heights on the surfaces of these films are changed by the different effective surface potential energies which increase from 0.49 to 0.75 eV in films annealed from 200 to 600 degrees C, but slightly decrease to 0.7 eV in films annealed up to 800 degrees C. (C) 1996 American Institute of Physics.
Electrical properties in arsenic-ion-implanted GaAs
(1996-08-01)
Chen, WC
;
Chang, CS
;
交大名義發表
;
光電工程學系
;
National Chiao Tung University
A model of effective surface potential energy is proposed to explain unknown behavior of carrier transport in film and leakage currents in Schottky diodes. X-ray photoelectron spectroscopy is employed to investigate a series of band diagrams of arsenic-ion-implanted GaAs films. It is shown that the effective surface potential energies, affected by the shift of core levels, are due to different microstructures and atomic environments in these films at different annealing temperatures. Moreover, the effective barrier heights on the surfaces of these films are changed by the different effective surface potential energies which increase from 0.49 to 0.75 eV in films annealed from 200 to 600 degrees C, but slightly decrease to 0.7 eV in films annealed up to 800 degrees C. (C) 1996 American Institute of Physics.
Electrochemical study on screen-printed carbon electrodes with modification by iron nanoparticles in Fe(CN)(6)(4-/3-) redox system
(2005-10-01)
Lee, SH
;
Fang, HY
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Chen, WC
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Lin, HM
;
Chang, CA
The remarkable enhancement of electron transfer on screen-printed carbon electrodes (SPCEs) with modification by iron nanoparticles (Fe-nano), coupled with Fe(CN)(6)(4-/3-) redox species, was characterized with an increase of electroactive area (A(ea)) at electrode surface together with a decrease of heterogeneous. electron transfer rate constant (k degrees) in the system. Hence, Fe-nano-Fe(CN)(6)(3-) SPCEs with deposition of glucose oxidase (GOD) demonstrated a higher sensitivity to various glucose concentrations than Fe(CN)(6)(3-)/GOD-deposited SPCEs. In addition, an inhibited diffusion current from cyclic voltammograms was also observed with an increase in redox concentration and complicated the estimation of A(ea). Further analysis by the electrochemical impedance method, it was shown that this effect might be resulted from the electrode surface blocking by the products of activated complex decomposition.
Growth temperature reduction for isoelectronic As-doped GaN
(2003-03-01)
Lee, WH
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Huang, HY
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Chen, WC
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Lee, CF
;
Chen, WK
As-doped GaN films were grown at different temperatures by atmospheric metalorganic chemical vapor deposition. A higher electron Hall mobility, narrower line width in photoluminescence, and longer spatial correlation length of the filmes were obtainable at low growth temperatures compared to undoped GaN grown at the same temperatures as a result of isoelectronic As-doping.
Integration of Reusable Software Components and frameworks into a visual software construction approach
(2000-11-01)
Chen, DJ
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Koong, CS
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Chen, WC
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Huang, SK
;
van Diepen, NWP
Software reuse is an effective means of improving software productivity and software quality. Reusable Software Components (RSCs) are the basic building components for software programs constructed using the software reuse approach. The object-oriented approach is used to design and implement our RSCs. Our laboratory has already implemented more than 300 reusable software components, including design-level frameworks in various application domains and approximately 200,000 lines of code in our library. These components and frameworks have been accumulated in the course of designing and implementing strategy-based game systems, multimedia authoring systems (2-D and 3-D), multimedia playback systems, and other application systems. Multimedia software plays an important role in the software industry. In contrast to traditional software, multimedia software provides users with visual and audio effects through their interfaces and can more accurately model the real world. A media component may contain various elements, such as text descriptions, voice narration, and animation sequences, which more closely present the subject to be modeled. Such a reusable media component is commonly referred to as a Multimedia Reusable Component(MRC). Using RSCs, frameworks, and MRCs, our laboratory has successfully designed and implemented a commercial product called DIY Magic Cartoon World for use in making subject-based cartoons. The RSCs and frameworks can be visualized as icons for a visual programming model. Reuse-in-large practice is, therefore, achieved using visual programming techniques based on these visualized components. In this study, we introduce design principles and implementation techniques for our RSCs, frameworks, and MRCs. RSCs, frameworks, and MRCs are integrated into a visual software construction approach. More specifically, the design concept and implementation of an approachfor visual software construction are described. In addition to discussing the advantages of the proposed construction approach, this work also presents examples which illustrate how the visual programming environment is used.
Investigation of the thermal properties of novel adamantane-modified polybenzoxazine
(2004-11-05)
Su, YC
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Chen, WC
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Chang, FC
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應用化學系
;
Department of Applied Chemistry
Two novel structures of adamantane-modified benzoxazines were synthesized from 4-(1-adamantyl)-phenol through the incorporation of adamantane as a pendant group into the polybenzoxazine backbone. Both H-1-NMR and Fourier transform infrared spectra were used to characterize these structures. The rigid structure of the adamantane tended to hinder the chain mobility (boat anchor effect) and substantially enhanced the thermal properties, including the glass-transition temperature and decomposition temperature, especially for poly(6-adamantyl-3-methyl-3,4-dihydro-2H-1,3-benzoxazine). In the poly(6-adamantyl-3-phenyl-3,4-dihydro-2H-1,3-benzoxazine) system, however, the opposite result for the glass-transition temperature was observed and it was interpreted as lower crosslinking density. The phenyl group was bulkier than the methyl group, and the movement of the molecular chain was hindered between bridging points during the curing process; this resulted in a lower crosslinking density and a lower glass-transition temperature than those of poly(6-adamantyl-3-methyl-3,4-dihydro-2H-1,3-benzoxazine). (C) 2004 Wiley Periodicals, Inc.
Material and ultrafast optoelectronic properties of furnace-annealed arsenic-ion-implanted GaAs
(1998-09-01)
Lin, GR
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Chen, WC
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Chang, CS
;
Chao, SC
;
Wu, KH
Structural, electrical, and ultrafast optical properties of furnace-annealed arsenic-ion-implanted GaAs (GaAs:As+) has been investigated for its applications in ultrafast optoelectronics, From these studies, we determine that GaAs substrates implanted with 200-keV arsenic ions at 10(16) ions/cm(2) and furnace-annealed at 500 degrees C-600 degrees C would have recovered its crystallinity, be highly resistive, and exhibit picosecond photo-excited carrier lifetimes. The duration of the electrical pulses generated by photoconductive switches (PCS's) fabricated on the optimized material was approximate to 4 ps, The risetime (10%-90%) and 1/e falltime were, respectively, approximate to 2 and 3 ps, These results were measurement-system limited, We estimated the actual response to be approximate to 2 ps, consistent with a photo-excited carrier lifetime of approximate to 1.8 ps. The peak responsivity was greater than or equal to 4x10(-3) A/W. The dark current for the GaAs:As+ PCS biased at 40 V was as low as 5 nA. The break down field was higher than 150 kV/cm, These characteristics are comparable to those of state-of-the-art photoconductors such as LT-GaAs.
Microphotoluminescence spectra of hillocks in Al0.11Ga0.89N films
(2004-10-11)
Ke, WC
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Ku, CS
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Huang, HY
;
Chen, WC
;
Lee, L
The spatial variation of the optical properties of hillocks in Al0.11Ga0.89N films has been studied by using microphotoluminescence (mu-PL) microscopy. The mu-PL spectrum revealed a strong emission (I-H) at 351 nm from the hillock, besides the near-band-edge emission (I-nbe) at 341 nm. Moreover, the I-H intensity increases significantly and its full width at half maximum decreases from similar to76 to similar to53 meV by probing across the hillock center. These indicated that the hillock structure is a strong emission center. The temperature-dependent mu-PL, measurements showed that the I-H also has the S-shape behavior with a transition temperature of similar to120 K which is lower than that of I-nbe. The redshift of I-H is also smaller than I-nbe. Both indicated that the Al composition in hillocks is lower than the surrounding area. (C) 2004 American Institute of Physics.