Pub Date : 2004-06-21DOI: 10.1109/DRC.2004.1367780
J. Koohsorkhi, H. Hoseinzadegan, S. Mohajerzadeh, M. Robertson
We report the fabrication of novel field-emission transistors on silicon substrates using vertically grown carbon nano-tubes. Transistors made here are formed on clusters of carbon nano-tubes and do not need nano-lithography. The main feature of the structure is the vertically grown nano-tubes on a silicon substrate, acting as the cathodes for the field emission phenomenon. The level of emission is controlled mainly by the voltage applied between the laterally-placed gate electrode and the silicon cathode electrode. Microscale lithography can be used to fabricate well-defined arrays of transistors suitable for switching applications. Further characterization of the tubes is underway.
{"title":"Novel self-defined field emission transistors with PECVD-grown carbon nano-tubes on silicon substrates","authors":"J. Koohsorkhi, H. Hoseinzadegan, S. Mohajerzadeh, M. Robertson","doi":"10.1109/DRC.2004.1367780","DOIUrl":"https://doi.org/10.1109/DRC.2004.1367780","url":null,"abstract":"We report the fabrication of novel field-emission transistors on silicon substrates using vertically grown carbon nano-tubes. Transistors made here are formed on clusters of carbon nano-tubes and do not need nano-lithography. The main feature of the structure is the vertically grown nano-tubes on a silicon substrate, acting as the cathodes for the field emission phenomenon. The level of emission is controlled mainly by the voltage applied between the laterally-placed gate electrode and the silicon cathode electrode. Microscale lithography can be used to fabricate well-defined arrays of transistors suitable for switching applications. Further characterization of the tubes is underway.","PeriodicalId":385948,"journal":{"name":"Conference Digest [Includes 'Late News Papers' volume] Device Research Conference, 2004. 62nd DRC.","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123707964","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 : 2004-06-21DOI: 10.1109/DRC.2004.1367862
R. Martel, J. Misewichtt, J. Tsang, P. Avouris
Single-walled carbon nanotubes (SWNTs) are tubular 1D nanostructures made of /spl pi/ conjugated C-C bonds. The nanotube band structure consists of unique sets of 1D subbands resulting in sharp peaks in the density of states (DOS). These DOS lead to strong optical interband transitions as observed in recent absorption and emission experiments. Here, we present a novel electroluminescence device based on ambipolar carbon nanotube FETs. The device enables efficient charge injection across the metal-nanotube contact barrier and the band gap recombination of carriers in the nanotube with an emission in the near IR. To our knowledge, this nanotube device represents the smallest electrically pumped optical emission source. It also opens up new possibilities for fundamental study of electron-hole interactions in 1D and in both electronics and optoelectronics.
{"title":"IR emission from Schottky barrier carbon nanotube FETs","authors":"R. Martel, J. Misewichtt, J. Tsang, P. Avouris","doi":"10.1109/DRC.2004.1367862","DOIUrl":"https://doi.org/10.1109/DRC.2004.1367862","url":null,"abstract":"Single-walled carbon nanotubes (SWNTs) are tubular 1D nanostructures made of /spl pi/ conjugated C-C bonds. The nanotube band structure consists of unique sets of 1D subbands resulting in sharp peaks in the density of states (DOS). These DOS lead to strong optical interband transitions as observed in recent absorption and emission experiments. Here, we present a novel electroluminescence device based on ambipolar carbon nanotube FETs. The device enables efficient charge injection across the metal-nanotube contact barrier and the band gap recombination of carriers in the nanotube with an emission in the near IR. To our knowledge, this nanotube device represents the smallest electrically pumped optical emission source. It also opens up new possibilities for fundamental study of electron-hole interactions in 1D and in both electronics and optoelectronics.","PeriodicalId":385948,"journal":{"name":"Conference Digest [Includes 'Late News Papers' volume] Device Research Conference, 2004. 62nd DRC.","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115213811","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 : 2004-06-21DOI: 10.1109/DRC.2004.1367836
M. Holub, S. Fathpour, S. Chakrabarti, J. Topol'ancik, P. Bhattacharya, Y. Lei
We believe our demonstration of high-temperature operation in a GaMnAs spin-LED to be an important step in the quest toward room-temperature spin-LED operation. In this paper, we have investigated the properties of Mn-doped InAs quantum dot multilayers grown by LT-MBE. We find that the dilute magnetic quantum dot samples exhibit ferromagnetic behavior at and above room-temperature, possibly resulting from the joint effects of quantum confinement, epitaxial strain, and disorder introduced by the self-organization process. Electron energy loss spectroscopy (EELS) indicates that the Mn atoms incorporate predominantly with the InAs dots. Work is currently underway to incorporate InAs:Mn QDs in the spin-aligner of a spin-LED to demonstrate room-temperature operation; our results are presented.
{"title":"High-temperature spin-polarized quantum dot light-emitting diodes","authors":"M. Holub, S. Fathpour, S. Chakrabarti, J. Topol'ancik, P. Bhattacharya, Y. Lei","doi":"10.1109/DRC.2004.1367836","DOIUrl":"https://doi.org/10.1109/DRC.2004.1367836","url":null,"abstract":"We believe our demonstration of high-temperature operation in a GaMnAs spin-LED to be an important step in the quest toward room-temperature spin-LED operation. In this paper, we have investigated the properties of Mn-doped InAs quantum dot multilayers grown by LT-MBE. We find that the dilute magnetic quantum dot samples exhibit ferromagnetic behavior at and above room-temperature, possibly resulting from the joint effects of quantum confinement, epitaxial strain, and disorder introduced by the self-organization process. Electron energy loss spectroscopy (EELS) indicates that the Mn atoms incorporate predominantly with the InAs dots. Work is currently underway to incorporate InAs:Mn QDs in the spin-aligner of a spin-LED to demonstrate room-temperature operation; our results are presented.","PeriodicalId":385948,"journal":{"name":"Conference Digest [Includes 'Late News Papers' volume] Device Research Conference, 2004. 62nd DRC.","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129651139","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 : 2004-06-21DOI: 10.1109/DRC.2004.1367815
K. Lee, G. Blanchet, F. Gao, Y. Loo
Polyaniline (PANI) - in its conductive form - is an attractive candidate for organic and polymer electronics because of its chemical and environmental stability. Due to the difficulties associated with materials processing, however, fabricating PANI electronic components has been challenging. In this paper, we report a simple, low-cost technique for patterning water-dispersible, conductive PANI. Unlike previous techniques, where the polyaniline has to be doped post-processing to render electrical conductivity, our patterning scheme uses predoped aqueous solutions of PANI. Our technique relies on specific interactions between doped PANI and the substrate; patterns as small as 20 /spl mu/m can be routinely fabricated. To demonstrate patterning versatility, we fabricated and tested pentacene thin-film transistors (TFTs) that use PANI source and drain electrodes.
{"title":"Fabrication and testing of pentacene thin-film transistors that use water-dispersible polyaniline electrodes","authors":"K. Lee, G. Blanchet, F. Gao, Y. Loo","doi":"10.1109/DRC.2004.1367815","DOIUrl":"https://doi.org/10.1109/DRC.2004.1367815","url":null,"abstract":"Polyaniline (PANI) - in its conductive form - is an attractive candidate for organic and polymer electronics because of its chemical and environmental stability. Due to the difficulties associated with materials processing, however, fabricating PANI electronic components has been challenging. In this paper, we report a simple, low-cost technique for patterning water-dispersible, conductive PANI. Unlike previous techniques, where the polyaniline has to be doped post-processing to render electrical conductivity, our patterning scheme uses predoped aqueous solutions of PANI. Our technique relies on specific interactions between doped PANI and the substrate; patterns as small as 20 /spl mu/m can be routinely fabricated. To demonstrate patterning versatility, we fabricated and tested pentacene thin-film transistors (TFTs) that use PANI source and drain electrodes.","PeriodicalId":385948,"journal":{"name":"Conference Digest [Includes 'Late News Papers' volume] Device Research Conference, 2004. 62nd DRC.","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130116342","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 : 2004-06-21DOI: 10.1109/DRC.2004.1367898
Y. Sun, A. Yulius, J. Woodall
By integrating InP photodiodes with Si, we can take advantage of the low cost and robustness of large Si substrates. However, the major challenge of this strategy is the high density of dislocations in InP grown on Si, due to the 8% lattice mismatch and large difference in thermal expansion coefficient. Large concentrations of dislocations act as recombination centers which greatly deteriorates the performance of the InP photodiodes. We have developed InP photodiodes whose photo-active regions have large electric fields in order to achieve high quantum efficiencies, even with defected material. We use a GaP substrate as the first step since GaP is lattice matched to Si, which could be used as a buffer layer between InP and Si. We compared two different structures: a normal p-i-n structure and a drift dominated structure.
{"title":"A high performance photodetector using a novel drift dominated structure in defected materials","authors":"Y. Sun, A. Yulius, J. Woodall","doi":"10.1109/DRC.2004.1367898","DOIUrl":"https://doi.org/10.1109/DRC.2004.1367898","url":null,"abstract":"By integrating InP photodiodes with Si, we can take advantage of the low cost and robustness of large Si substrates. However, the major challenge of this strategy is the high density of dislocations in InP grown on Si, due to the 8% lattice mismatch and large difference in thermal expansion coefficient. Large concentrations of dislocations act as recombination centers which greatly deteriorates the performance of the InP photodiodes. We have developed InP photodiodes whose photo-active regions have large electric fields in order to achieve high quantum efficiencies, even with defected material. We use a GaP substrate as the first step since GaP is lattice matched to Si, which could be used as a buffer layer between InP and Si. We compared two different structures: a normal p-i-n structure and a drift dominated structure.","PeriodicalId":385948,"journal":{"name":"Conference Digest [Includes 'Late News Papers' volume] Device Research Conference, 2004. 62nd DRC.","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124631333","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 : 2004-06-21DOI: 10.1109/DRC.2004.1367897
Chih-Fang Huang, I. Perez, F. Zhao, J. Torvik, R. Irwin, K. Torvik, F. Abrhaley, B. van Zeghbroeck
4H-SiC BJTs with multiple finger structure were designed and fabricated. Large devices with 0.52 mm/sup 2/ active area show DC gain around 18. A class A power amplifier is designed at 450 MHz using a single cell large device. Matching at the input is done with a parallel capacitor and a transmission line. The device is biased at V/sub CE/=180 V and pulsed with 0.1 % duty cycle to avoid self-heating. A maximum output power of 215 W is achieved with a power gain of 7.5 dB, corresponding to a power density of 4.3 W/mm normalized to emitter finger length.
{"title":"215W pulsed class A UHF power amplification based on SiC bipolar technology","authors":"Chih-Fang Huang, I. Perez, F. Zhao, J. Torvik, R. Irwin, K. Torvik, F. Abrhaley, B. van Zeghbroeck","doi":"10.1109/DRC.2004.1367897","DOIUrl":"https://doi.org/10.1109/DRC.2004.1367897","url":null,"abstract":"4H-SiC BJTs with multiple finger structure were designed and fabricated. Large devices with 0.52 mm/sup 2/ active area show DC gain around 18. A class A power amplifier is designed at 450 MHz using a single cell large device. Matching at the input is done with a parallel capacitor and a transmission line. The device is biased at V/sub CE/=180 V and pulsed with 0.1 % duty cycle to avoid self-heating. A maximum output power of 215 W is achieved with a power gain of 7.5 dB, corresponding to a power density of 4.3 W/mm normalized to emitter finger length.","PeriodicalId":385948,"journal":{"name":"Conference Digest [Includes 'Late News Papers' volume] Device Research Conference, 2004. 62nd DRC.","volume":"236 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116188827","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 : 2004-06-21DOI: 10.1109/DRC.2004.1367901
M. Chabinyc, J. Lu, A. Salleo, R. Street
Thin-film transistors (TFTs) made with solution-processed polymeric semiconductors are being developed for use in large-area, low-cost electronic devices such as displays. The carrier mobility in most polymers is about ten times smaller than that in amorphous silicon. To be useful for circuits, the dimensions of TFTs made with polymers must be scaled to compensate for this deficiency because high-quality, ultra-thin or high-k dielectrics are not available for these applications. Deviations from ideal FET behavior are widely reported for polymer TFTs with channel lengths shorter than /spl sim/10 /spl mu/m and these deviations are currently not understood. In this paper, we present an explanation of this phenomenon for the first time. 2D simulations will be necessary to further model the current-voltage characteristics. These data are important for the development of device models for polymeric circuits and for the determination of materials properties from I-V characteristics of TFTs.
{"title":"Current enhancement in regioregular poly(thiophene) thin film transistors","authors":"M. Chabinyc, J. Lu, A. Salleo, R. Street","doi":"10.1109/DRC.2004.1367901","DOIUrl":"https://doi.org/10.1109/DRC.2004.1367901","url":null,"abstract":"Thin-film transistors (TFTs) made with solution-processed polymeric semiconductors are being developed for use in large-area, low-cost electronic devices such as displays. The carrier mobility in most polymers is about ten times smaller than that in amorphous silicon. To be useful for circuits, the dimensions of TFTs made with polymers must be scaled to compensate for this deficiency because high-quality, ultra-thin or high-k dielectrics are not available for these applications. Deviations from ideal FET behavior are widely reported for polymer TFTs with channel lengths shorter than /spl sim/10 /spl mu/m and these deviations are currently not understood. In this paper, we present an explanation of this phenomenon for the first time. 2D simulations will be necessary to further model the current-voltage characteristics. These data are important for the development of device models for polymeric circuits and for the determination of materials properties from I-V characteristics of TFTs.","PeriodicalId":385948,"journal":{"name":"Conference Digest [Includes 'Late News Papers' volume] Device Research Conference, 2004. 62nd DRC.","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124370519","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 : 2004-06-21DOI: 10.1109/DRC.2004.1367796
B. Hekmatshoar, S. Mohajerzadeh, D. Shahrjerdi, M. Robertson
Tunneling and depletion-mode poly-Ge TFTs were fabricated at temperatures as low as 150/spl deg/C and 200/spl deg/C respectively. Fabrication of the tunneling TFTs was based on stress-assisted lateral growth of Ge from Cu-seeded islands. In a different approach, depletion-mode TFTs were fabricated, based on metal-free crystallization of Ge by successive steps of hydrogenation and annealing.
{"title":"Tunneling and depletion-mode TFTs fabricated by low-temperature stress-assisted Cu-induced lateral growth and metal-free crystallization of germanium","authors":"B. Hekmatshoar, S. Mohajerzadeh, D. Shahrjerdi, M. Robertson","doi":"10.1109/DRC.2004.1367796","DOIUrl":"https://doi.org/10.1109/DRC.2004.1367796","url":null,"abstract":"Tunneling and depletion-mode poly-Ge TFTs were fabricated at temperatures as low as 150/spl deg/C and 200/spl deg/C respectively. Fabrication of the tunneling TFTs was based on stress-assisted lateral growth of Ge from Cu-seeded islands. In a different approach, depletion-mode TFTs were fabricated, based on metal-free crystallization of Ge by successive steps of hydrogenation and annealing.","PeriodicalId":385948,"journal":{"name":"Conference Digest [Includes 'Late News Papers' volume] Device Research Conference, 2004. 62nd DRC.","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128197498","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 : 2004-06-21DOI: 10.1109/DRC.2004.1367817
E. Lind, P. Lindstrom, A. Nauen, L. Wernersson
In this paper, we show that a three terminal resonant tunneling transistor can be used to obtain pulsed operation of a resonant tunneling based oscillator. We have developed a technology to embed nm-sized metallic features in close vicinity to semiconductor heterostructures which allows a direct integration of resonant tunneling diodes inside the channel of a permeable base transistor, thus forming a resonant tunneling permeable base transistor (RT-PBT). When biased in the NDR-region, the RT-PBT works as a negative resistance oscillator. A fundamental oscillation frequency of 800 MHz was detected, with higher harmonics up to 2.6 GHz. Varying the gate voltage shifted the oscillation frequency, showing the possibility of using the RT-PBT as a voltage controlled oscillator.
{"title":"Resonant tunneling permeable base transistor based pulsed oscillator","authors":"E. Lind, P. Lindstrom, A. Nauen, L. Wernersson","doi":"10.1109/DRC.2004.1367817","DOIUrl":"https://doi.org/10.1109/DRC.2004.1367817","url":null,"abstract":"In this paper, we show that a three terminal resonant tunneling transistor can be used to obtain pulsed operation of a resonant tunneling based oscillator. We have developed a technology to embed nm-sized metallic features in close vicinity to semiconductor heterostructures which allows a direct integration of resonant tunneling diodes inside the channel of a permeable base transistor, thus forming a resonant tunneling permeable base transistor (RT-PBT). When biased in the NDR-region, the RT-PBT works as a negative resistance oscillator. A fundamental oscillation frequency of 800 MHz was detected, with higher harmonics up to 2.6 GHz. Varying the gate voltage shifted the oscillation frequency, showing the possibility of using the RT-PBT as a voltage controlled oscillator.","PeriodicalId":385948,"journal":{"name":"Conference Digest [Includes 'Late News Papers' volume] Device Research Conference, 2004. 62nd DRC.","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121312431","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 : 2004-06-21DOI: 10.1109/DRC.2004.1367777
S. Ryu, S. Krishnaswami, M. O'loughlin, J. Richmond, A. Agarwal, J. Palmour, A.R. Heffier
Power MOSFETs in 4H-SiC are very attractive for high voltage switching applications because of their low specific on-resistances and fast, temperature independent switching characteristics. We present our latest results in 10 kV 4H-SiC DMOSFET development - a specific on-resistance of 123 m/spl Omega//spl middot/cm/sup 2/ is demonstrated, which is a 42% reduction in specific on-resistance. This is the lowest specific on-resistance value ever reported for 10 kV class majority carrier switches.
{"title":"10 kV, 123 m/spl Omega/-cm/sup 2/ 4H-SiC power DMOSFETs","authors":"S. Ryu, S. Krishnaswami, M. O'loughlin, J. Richmond, A. Agarwal, J. Palmour, A.R. Heffier","doi":"10.1109/DRC.2004.1367777","DOIUrl":"https://doi.org/10.1109/DRC.2004.1367777","url":null,"abstract":"Power MOSFETs in 4H-SiC are very attractive for high voltage switching applications because of their low specific on-resistances and fast, temperature independent switching characteristics. We present our latest results in 10 kV 4H-SiC DMOSFET development - a specific on-resistance of 123 m/spl Omega//spl middot/cm/sup 2/ is demonstrated, which is a 42% reduction in specific on-resistance. This is the lowest specific on-resistance value ever reported for 10 kV class majority carrier switches.","PeriodicalId":385948,"journal":{"name":"Conference Digest [Includes 'Late News Papers' volume] Device Research Conference, 2004. 62nd DRC.","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124718202","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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