Pub Date : 2002-08-07DOI: 10.1109/MIEL.2002.1003295
R. Ramović, M. Jevtic, J. Hadzi-Vukovic, D. Randjelović
This paper presents a novel analytical model for simulation of characteristics of a n-channel MOSFET based on silicon-carbide (SiC). Using known experimental results, a semiempirical relation for carrier mobility (/spl mu/) dependence on electric field intensity, dopant concentration and temperature was formulated. Based on this relation appropriate analytical mathematical-physical model for simulation of current-voltage characteristics, transconductance and conductance of MOSFET were developed. All models were formulated taking into account, among other effects, the dependence of threshold voltage on temperature and impurity concentration in the channel, as well as the effect of the channel narrowing. Using the proposed model a simulation algorithm was designed and a simulation of the MOSFET's performance was performed. Results of the simulation are graphically presented in and discussed.
{"title":"A novel analytical model of a SiC MOSFET","authors":"R. Ramović, M. Jevtic, J. Hadzi-Vukovic, D. Randjelović","doi":"10.1109/MIEL.2002.1003295","DOIUrl":"https://doi.org/10.1109/MIEL.2002.1003295","url":null,"abstract":"This paper presents a novel analytical model for simulation of characteristics of a n-channel MOSFET based on silicon-carbide (SiC). Using known experimental results, a semiempirical relation for carrier mobility (/spl mu/) dependence on electric field intensity, dopant concentration and temperature was formulated. Based on this relation appropriate analytical mathematical-physical model for simulation of current-voltage characteristics, transconductance and conductance of MOSFET were developed. All models were formulated taking into account, among other effects, the dependence of threshold voltage on temperature and impurity concentration in the channel, as well as the effect of the channel narrowing. Using the proposed model a simulation algorithm was designed and a simulation of the MOSFET's performance was performed. Results of the simulation are graphically presented in and discussed.","PeriodicalId":221518,"journal":{"name":"2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131491368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-07DOI: 10.1109/MIEL.2002.1003147
B. Charlot, B. Courtois, H. Delori, J.-F. Paillotin, K. Torki
CMP aims at providing Universities, Research Laboratories and Industries with the possibility to have their integrated circuits projects fabricated for prototyping and low volume production. Presently, users are serviced for CMOS double layer poly/double layer metal (DLP/DLM) 0.8 /spl mu/, DLM/TLM 0.6 /spl mu/, DLP/4LM 0.35 /spl mu/, SLP/6LM 0.18 /spl mu/ and 0.12 /spl mu/, BiCMOS DLP/DLM 0.8 /spl mu/, SiGe BiCMOS DLP/DLM 0.8 /spl mu/ and 5 LM 0.35 /spl mu/, and HEMT GaAs 0.2 /spl mu/. About 40 multi-project runs are offered per year. Micro Electro Mechanical Systems (MEMS) are provided in standard CMP runs in CMOS DLP/DLM 0.8 /spl mu/m and DLM/TLM 0.6 /spl mu/, BiCMOS DLP/DLM 0.8 /spl mu/ and HEMT GaAs 0.2 /spl mu/, using compatible front-side bulk micro-machining. MUMPS process is offered as a surface micro-machining allowing one to integrate MEMS only microstructures. This paper describes the services available, focusing on the most advanced IC processes and on the MEMS processes.
{"title":"Access to microsystem technology: the CMP services solution","authors":"B. Charlot, B. Courtois, H. Delori, J.-F. Paillotin, K. Torki","doi":"10.1109/MIEL.2002.1003147","DOIUrl":"https://doi.org/10.1109/MIEL.2002.1003147","url":null,"abstract":"CMP aims at providing Universities, Research Laboratories and Industries with the possibility to have their integrated circuits projects fabricated for prototyping and low volume production. Presently, users are serviced for CMOS double layer poly/double layer metal (DLP/DLM) 0.8 /spl mu/, DLM/TLM 0.6 /spl mu/, DLP/4LM 0.35 /spl mu/, SLP/6LM 0.18 /spl mu/ and 0.12 /spl mu/, BiCMOS DLP/DLM 0.8 /spl mu/, SiGe BiCMOS DLP/DLM 0.8 /spl mu/ and 5 LM 0.35 /spl mu/, and HEMT GaAs 0.2 /spl mu/. About 40 multi-project runs are offered per year. Micro Electro Mechanical Systems (MEMS) are provided in standard CMP runs in CMOS DLP/DLM 0.8 /spl mu/m and DLM/TLM 0.6 /spl mu/, BiCMOS DLP/DLM 0.8 /spl mu/ and HEMT GaAs 0.2 /spl mu/, using compatible front-side bulk micro-machining. MUMPS process is offered as a surface micro-machining allowing one to integrate MEMS only microstructures. This paper describes the services available, focusing on the most advanced IC processes and on the MEMS processes.","PeriodicalId":221518,"journal":{"name":"2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129382414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-07DOI: 10.1109/MIEL.2002.1003205
V. Shashkin, Y. Chechenin, V. Danil’tsev, O. Khrykin, A. Maslovsky, A. Murel, V. Vaks
The results of designing and investigation of a sensitivity of microwave detectors, based on planar GaAs diodes with low effective Schottky barrier height are reported. Low pressure metalorganic chemical vapor deposition (MOCVD) technology was used for the modification of the effective Schottky barrier height by means of precise /spl delta/-doping of near-surface layer and for successive deposition of an aluminium film in non-interrupted growth run. A complete quantum-mechanical numerical simulation of the effect produced by /spl delta/-doping on the current-voltage characteristic of the modified diodes is carried out. Comparison of computational results with the experimental characteristics of diodes shows a rather good agreement. Analysis of the carried-out research has allowed one to choose optimum parameters of /spl delta/-layers for producing low barrier diodes (/spl sim/0.2 eV) with a reasonable ideality factor (n<1.5). The best performance of the low barrier diode corresponding to /spl gamma/=5000 V/W and NEP=(3/spl divide/6)/spl middot/10/sup -12/ W/spl middot/Hz/sup -1/2/ at 150 GHz was at zero bias voltage.
{"title":"Planar Schottky diodes with low barrier height for microwave detector application","authors":"V. Shashkin, Y. Chechenin, V. Danil’tsev, O. Khrykin, A. Maslovsky, A. Murel, V. Vaks","doi":"10.1109/MIEL.2002.1003205","DOIUrl":"https://doi.org/10.1109/MIEL.2002.1003205","url":null,"abstract":"The results of designing and investigation of a sensitivity of microwave detectors, based on planar GaAs diodes with low effective Schottky barrier height are reported. Low pressure metalorganic chemical vapor deposition (MOCVD) technology was used for the modification of the effective Schottky barrier height by means of precise /spl delta/-doping of near-surface layer and for successive deposition of an aluminium film in non-interrupted growth run. A complete quantum-mechanical numerical simulation of the effect produced by /spl delta/-doping on the current-voltage characteristic of the modified diodes is carried out. Comparison of computational results with the experimental characteristics of diodes shows a rather good agreement. Analysis of the carried-out research has allowed one to choose optimum parameters of /spl delta/-layers for producing low barrier diodes (/spl sim/0.2 eV) with a reasonable ideality factor (n<1.5). The best performance of the low barrier diode corresponding to /spl gamma/=5000 V/W and NEP=(3/spl divide/6)/spl middot/10/sup -12/ W/spl middot/Hz/sup -1/2/ at 150 GHz was at zero bias voltage.","PeriodicalId":221518,"journal":{"name":"2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132160464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-07DOI: 10.1109/MIEL.2002.1003154
L. Lunardi
We review the state-of-the-art of heterojunction-based integrated circuit technologies that have potential applications for time division multiplexing (TDM) and wavelength division multiplexing (WDM) fiber optic communication systems.
{"title":"Semiconductor devices for fiber optic communication systems","authors":"L. Lunardi","doi":"10.1109/MIEL.2002.1003154","DOIUrl":"https://doi.org/10.1109/MIEL.2002.1003154","url":null,"abstract":"We review the state-of-the-art of heterojunction-based integrated circuit technologies that have potential applications for time division multiplexing (TDM) and wavelength division multiplexing (WDM) fiber optic communication systems.","PeriodicalId":221518,"journal":{"name":"2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122100499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-07DOI: 10.1109/MIEL.2002.1003330
I. Lemberski, M. Koegst, S. Cotofana, B. Juurlink
In this paper, we focus our attention on the problem of FSM state encoding for low power. In contrast to many publications where probabilistic approach to power estimation is offered, we consider power measurement based on given user-specified input sequence. Although the power dissipation depends on several parameters (register and output switching activity, complexity of combinational part, capacitance load on the gate), switching is the most important source of power dissipation. Our goal is to develop an encoding procedure which minimizes register switching activity. We start with a highly redundant (seed) encoding and minimize its length while minimizing the register switching activity. Unlike previous works, we don't restrict encoding final length (only register switching activity is considered). Therefore, final encoding length may differ from the minimal one. We tested our encoding procedure on several benchmarks from the MCNC set. The experiments show that in many cases, power dissipation obtained using our encoding (generally, of non-minimal length) is less than one achieved when encoding of minimal length is generated.
{"title":"FSM non-minimal state encoding for low power","authors":"I. Lemberski, M. Koegst, S. Cotofana, B. Juurlink","doi":"10.1109/MIEL.2002.1003330","DOIUrl":"https://doi.org/10.1109/MIEL.2002.1003330","url":null,"abstract":"In this paper, we focus our attention on the problem of FSM state encoding for low power. In contrast to many publications where probabilistic approach to power estimation is offered, we consider power measurement based on given user-specified input sequence. Although the power dissipation depends on several parameters (register and output switching activity, complexity of combinational part, capacitance load on the gate), switching is the most important source of power dissipation. Our goal is to develop an encoding procedure which minimizes register switching activity. We start with a highly redundant (seed) encoding and minimize its length while minimizing the register switching activity. Unlike previous works, we don't restrict encoding final length (only register switching activity is considered). Therefore, final encoding length may differ from the minimal one. We tested our encoding procedure on several benchmarks from the MCNC set. The experiments show that in many cases, power dissipation obtained using our encoding (generally, of non-minimal length) is less than one achieved when encoding of minimal length is generated.","PeriodicalId":221518,"journal":{"name":"2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122103318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-07DOI: 10.1109/MIEL.2002.1003215
O. Mrooz, I. Hadzarnan, M. Vakiv, O. Shpotyuk, J. Plewa, H. Altenburg, H. Uphoff
Aging phenomenon in copper-nickel-cobalt manganite NTC thermistors under thermal stresses at 125 and 170/spl deg/C during 1000 h was studied. The relative resistance drift observed in NTC thermistors is correlated with the results of Cu/sub 0.1/Ni/sub 0.8/Co/sub 0.2/Mn/sub 1.9/O/sub 4/ ceramic microstructures characterization (obtained by optical microscopy, SEM, electron probe and EDX microanalyses) and thermogravimetric analysis.
{"title":"Aging of copper-nickel-cobalt manganite NTC thermistors [Cu/sub 0.1/Ni/sub 0.8/Co/sub 0.2/Mn/sub 1.9/O/sub 4/]","authors":"O. Mrooz, I. Hadzarnan, M. Vakiv, O. Shpotyuk, J. Plewa, H. Altenburg, H. Uphoff","doi":"10.1109/MIEL.2002.1003215","DOIUrl":"https://doi.org/10.1109/MIEL.2002.1003215","url":null,"abstract":"Aging phenomenon in copper-nickel-cobalt manganite NTC thermistors under thermal stresses at 125 and 170/spl deg/C during 1000 h was studied. The relative resistance drift observed in NTC thermistors is correlated with the results of Cu/sub 0.1/Ni/sub 0.8/Co/sub 0.2/Mn/sub 1.9/O/sub 4/ ceramic microstructures characterization (obtained by optical microscopy, SEM, electron probe and EDX microanalyses) and thermogravimetric analysis.","PeriodicalId":221518,"journal":{"name":"2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125782123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-07DOI: 10.1109/MIEL.2002.1003202
V. Benda, J. Radil, T. Quan
The paper refers to a possibility to check carrier lifetime in the area close to the PN junction measuring forward characteristics at low current, densities, where generation-recombination portion of the current density dominates. The measurement allows one to determine energy level of dominant recombination centres and evaluate their concentration. The carrier lifetime in volume of the cell body can be evaluated using local irradiation of the surface of large-area solar cells with a laser diode (/spl lambda/=870 nm) from measured values of open circuit voltage V/sub oc/. The method can give information about recombination centres distribution in large-area solar cells. From V/sub oc/ distribution, position and extent of local defects can also be determined. Solar cell diagnostic methods can be used to investigate the influence of technology on characteristics of solar cells, with the aim of increasing efficiency and reliability of solar cells.
{"title":"In-process diagnostics of recombination centres in structures of large-area solar cells","authors":"V. Benda, J. Radil, T. Quan","doi":"10.1109/MIEL.2002.1003202","DOIUrl":"https://doi.org/10.1109/MIEL.2002.1003202","url":null,"abstract":"The paper refers to a possibility to check carrier lifetime in the area close to the PN junction measuring forward characteristics at low current, densities, where generation-recombination portion of the current density dominates. The measurement allows one to determine energy level of dominant recombination centres and evaluate their concentration. The carrier lifetime in volume of the cell body can be evaluated using local irradiation of the surface of large-area solar cells with a laser diode (/spl lambda/=870 nm) from measured values of open circuit voltage V/sub oc/. The method can give information about recombination centres distribution in large-area solar cells. From V/sub oc/ distribution, position and extent of local defects can also be determined. Solar cell diagnostic methods can be used to investigate the influence of technology on characteristics of solar cells, with the aim of increasing efficiency and reliability of solar cells.","PeriodicalId":221518,"journal":{"name":"2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127460049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-07DOI: 10.1109/MIEL.2002.1003180
P. Drljaca, M. Demierre, C. Schott, R. Popovic
We studied nonlinear behaviour of the angular position magnetic field sensor that consists of CMOS integrated circuit chip and a thin ferromagnetic disk. Developed numerical 3D model was compared with experimental results with a good agreement. Obtained numerical results were used to determine the linear magnetic working range of the sensor. We also calculated the nonlinear error for the disk positioning relative to the Hall elements and found 3.3% of error for the 10 /spl mu/m displacement. We proposed a simple amplitude calibration to strongly reduce nonlinearity coming from misalignment to 0.3% of the full scale. Additional nonlinearity from Hall elements has been discussed. The offset and sensitivity mismatch, contribute to the nonlinearity of the sensor less than 1/spl deg/.
{"title":"Nonlinear effects in magnetic angular position sensor with integrated flux concentrator","authors":"P. Drljaca, M. Demierre, C. Schott, R. Popovic","doi":"10.1109/MIEL.2002.1003180","DOIUrl":"https://doi.org/10.1109/MIEL.2002.1003180","url":null,"abstract":"We studied nonlinear behaviour of the angular position magnetic field sensor that consists of CMOS integrated circuit chip and a thin ferromagnetic disk. Developed numerical 3D model was compared with experimental results with a good agreement. Obtained numerical results were used to determine the linear magnetic working range of the sensor. We also calculated the nonlinear error for the disk positioning relative to the Hall elements and found 3.3% of error for the 10 /spl mu/m displacement. We proposed a simple amplitude calibration to strongly reduce nonlinearity coming from misalignment to 0.3% of the full scale. Additional nonlinearity from Hall elements has been discussed. The offset and sensitivity mismatch, contribute to the nonlinearity of the sensor less than 1/spl deg/.","PeriodicalId":221518,"journal":{"name":"2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130075267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-07DOI: 10.1109/MIEL.2002.1003344
R. Ubar, E. Orasson, H. Wuttke
A new teaching concept for teaching testing issues in digital design, which supports the possibility of distance learning as well as a Web-based computer-aided teaching is presented. It offers a set of tools ("interactive modules") to inspect the teaching topics and to carry out laboratory research. The interactive modules are focused on easy action and reaction, learning by doing, a game-like use, and fostering students in critical thinking, problem solving skills and creativity.
{"title":"Internet-based software for teaching test of digital circuits","authors":"R. Ubar, E. Orasson, H. Wuttke","doi":"10.1109/MIEL.2002.1003344","DOIUrl":"https://doi.org/10.1109/MIEL.2002.1003344","url":null,"abstract":"A new teaching concept for teaching testing issues in digital design, which supports the possibility of distance learning as well as a Web-based computer-aided teaching is presented. It offers a set of tools (\"interactive modules\") to inspect the teaching topics and to carry out laboratory research. The interactive modules are focused on easy action and reaction, learning by doing, a game-like use, and fostering students in critical thinking, problem solving skills and creativity.","PeriodicalId":221518,"journal":{"name":"2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128899817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-07DOI: 10.1109/MIEL.2002.1003292
Yutao Ma, Lifeng Chen, Jing Wang, L. Tian, Zhiping Yu, Litian Liu, Zhijian Li
A new simulator is developed including Quantum Mechanical Effects (QMEs) in the whole channel and gate tunneling current along the gate oxide. Schrodinger equation is solved using Modified Airy Function (MAF) method in the whole device including gate electrode, oxide and substrate and thus QMEs and tunneling effects can be taken into consideration at the same time. The simulator has high efficiency and accuracy. Advanced devices are simulated emphasizing QMEs and tunneling current through gate oxide.
{"title":"Simulation of nanometer-scale MOSFET's with ultra-thin gate oxide including full 2-dimensional quantum mechanical effects and gate tunneling current","authors":"Yutao Ma, Lifeng Chen, Jing Wang, L. Tian, Zhiping Yu, Litian Liu, Zhijian Li","doi":"10.1109/MIEL.2002.1003292","DOIUrl":"https://doi.org/10.1109/MIEL.2002.1003292","url":null,"abstract":"A new simulator is developed including Quantum Mechanical Effects (QMEs) in the whole channel and gate tunneling current along the gate oxide. Schrodinger equation is solved using Modified Airy Function (MAF) method in the whole device including gate electrode, oxide and substrate and thus QMEs and tunneling effects can be taken into consideration at the same time. The simulator has high efficiency and accuracy. Advanced devices are simulated emphasizing QMEs and tunneling current through gate oxide.","PeriodicalId":221518,"journal":{"name":"2002 23rd International Conference on Microelectronics. Proceedings (Cat. No.02TH8595)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130935163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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