Pub Date : 1981-03-01DOI: 10.1109/IEDM.1980.189824
C. De Santis, L. Jasper
A theoretical analysis is presented for a novel high power microwave/millimeter wave amplifier (herein called CEBA) that requires no radio frequency (RF) circuit structure. The electron beam is treated as an active dielectric serving the dual purpose of slow-wave circuit and amplification source. Amplification is obtained when beam-wave synchronism is met. The attractive features of low voltage, low magnetic field, wide frequency band-width, and low cost make the CEBA attractive for use as a lightweight inexpensive millimeter (mm) wave amplifier for air-borne and tactical applications.
{"title":"Circuitless electron beam amplifier (CEBA)","authors":"C. De Santis, L. Jasper","doi":"10.1109/IEDM.1980.189824","DOIUrl":"https://doi.org/10.1109/IEDM.1980.189824","url":null,"abstract":"A theoretical analysis is presented for a novel high power microwave/millimeter wave amplifier (herein called CEBA) that requires no radio frequency (RF) circuit structure. The electron beam is treated as an active dielectric serving the dual purpose of slow-wave circuit and amplification source. Amplification is obtained when beam-wave synchronism is met. The attractive features of low voltage, low magnetic field, wide frequency band-width, and low cost make the CEBA attractive for use as a lightweight inexpensive millimeter (mm) wave amplifier for air-borne and tactical applications.","PeriodicalId":180541,"journal":{"name":"1980 International Electron Devices Meeting","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1981-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116922245","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 : 1980-12-01DOI: 10.1109/IEDM.1980.189839
K. Lau, A. Yariv
The transverse modal behavior of the transverse junction stripe (TJS) laser excited by short (70 ps) electrical pulse is investigated experimentally and theoretically, It is predicted theoretically and observed experimentally that the transverse mode strongly depends on the excitation pulse amplitude and the dc bias current (which is set below threshold), This dependence is found to be due to transient lateral carrier diffusion at the lasing junction.
{"title":"Transverse modal behavior of transverse junction stripe laser excited by short electrical pulse","authors":"K. Lau, A. Yariv","doi":"10.1109/IEDM.1980.189839","DOIUrl":"https://doi.org/10.1109/IEDM.1980.189839","url":null,"abstract":"The transverse modal behavior of the transverse junction stripe (TJS) laser excited by short (70 ps) electrical pulse is investigated experimentally and theoretically, It is predicted theoretically and observed experimentally that the transverse mode strongly depends on the excitation pulse amplitude and the dc bias current (which is set below threshold), This dependence is found to be due to transient lateral carrier diffusion at the lasing junction.","PeriodicalId":180541,"journal":{"name":"1980 International Electron Devices Meeting","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1980-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131728751","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 : 1900-01-01DOI: 10.1109/IEDM.1980.189872
M. Caplan, D. Dimas, J. Tancredi, D. Birnbaum
A magnetron injection gun operating with temperature limited electron emission has been designed for a gyrotron amplifier. A series of computer models of the gun anode region were used to determine selected thermal and structural characteristics. Their effects on electron beam energy, velocity spread, and temperature were evaluated. The thermal analysis yielded the steady state temperatures of 137 node points, Thermally induced mechanical expansions were found to be 0.20% axially and 0.8296 radially. In the three dimensional coordinate system utilized, the stresses in 373 elements were numerically evaluated, The cathode heater warm-up characteristic was such that a 9 watt input heater power brought the cathode emitter up to 1068°C in 500 seconds. The cathode cooling due to electron emission was found to increase the steady state heater input power requirement by 1196 (for an emitter temperature of 1065°C) from 9 W to 11 W. The electron trajectory analysis included an evaluation of the beam energy, velocity spread, and temperature. The effect of the deformed mechanical shapes on the beam parameters was determined. A two dimensional computer simulation was used to graphically depict the electron trajectories in the gun anode region.
{"title":"Thermal and mechanical effects on gyrotron gun anode electrical performance","authors":"M. Caplan, D. Dimas, J. Tancredi, D. Birnbaum","doi":"10.1109/IEDM.1980.189872","DOIUrl":"https://doi.org/10.1109/IEDM.1980.189872","url":null,"abstract":"A magnetron injection gun operating with temperature limited electron emission has been designed for a gyrotron amplifier. A series of computer models of the gun anode region were used to determine selected thermal and structural characteristics. Their effects on electron beam energy, velocity spread, and temperature were evaluated. The thermal analysis yielded the steady state temperatures of 137 node points, Thermally induced mechanical expansions were found to be 0.20% axially and 0.8296 radially. In the three dimensional coordinate system utilized, the stresses in 373 elements were numerically evaluated, The cathode heater warm-up characteristic was such that a 9 watt input heater power brought the cathode emitter up to 1068°C in 500 seconds. The cathode cooling due to electron emission was found to increase the steady state heater input power requirement by 1196 (for an emitter temperature of 1065°C) from 9 W to 11 W. The electron trajectory analysis included an evaluation of the beam energy, velocity spread, and temperature. The effect of the deformed mechanical shapes on the beam parameters was determined. A two dimensional computer simulation was used to graphically depict the electron trajectories in the gun anode region.","PeriodicalId":180541,"journal":{"name":"1980 International Electron Devices Meeting","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115311569","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 : 1900-01-01DOI: 10.1109/IEDM.1980.189774
H. Fu, J. Manoliu, J. Moll
This paper describes a new method for fabricating MOSFETs with self-registering contacts to the source-drain and polysilicon gate regions. Contacts to the source-drain and gate regions are made through a second level of polysilicon which is directly deposited in contact with the doped source-drain and gate regions. Isolations are obtained by selectively oxidizing the entire layer of the second level polysilicon using a thin layer of silicon nitride as an oxidation mask. Metal is only needed in the areas where interconnects cross over the source-drain or gate regions. For an MOS circuit with buried contacts, this approach requires one less mask than the conventional approach since no buried contact masking is needed. Metal silicide can be incorporated into the second level of polysilicon to reduce the lire resistance of this interconnecting layer. Refractory metal or refractory metal silicide can also be used as the gate material. Some experimental results on devices fabricated using the new process will be presented.
{"title":"A new MOS transistor design with self-registering source-drain and gate contacts","authors":"H. Fu, J. Manoliu, J. Moll","doi":"10.1109/IEDM.1980.189774","DOIUrl":"https://doi.org/10.1109/IEDM.1980.189774","url":null,"abstract":"This paper describes a new method for fabricating MOSFETs with self-registering contacts to the source-drain and polysilicon gate regions. Contacts to the source-drain and gate regions are made through a second level of polysilicon which is directly deposited in contact with the doped source-drain and gate regions. Isolations are obtained by selectively oxidizing the entire layer of the second level polysilicon using a thin layer of silicon nitride as an oxidation mask. Metal is only needed in the areas where interconnects cross over the source-drain or gate regions. For an MOS circuit with buried contacts, this approach requires one less mask than the conventional approach since no buried contact masking is needed. Metal silicide can be incorporated into the second level of polysilicon to reduce the lire resistance of this interconnecting layer. Refractory metal or refractory metal silicide can also be used as the gate material. Some experimental results on devices fabricated using the new process will be presented.","PeriodicalId":180541,"journal":{"name":"1980 International Electron Devices Meeting","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116239904","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 : 1900-01-01DOI: 10.1109/IEDM.1980.189860
M. Siracusa, Z. Lemnios, D. Maki
This paper reports on the fabrication of an X-band GaAs microstrip amplifier as a test vehicle to establish a monolithic process capability. A variety of components are integrated on this circuit, including overlay and interdigital capacitors, via holes, air bridges and transmission lines. A novel geometry for overlay capacitors will be presented that has greatly improved yield and breakdown voltage over previous designs. Due to skin depth consideration, thick (∼ 2 µm) metallization layers are required on these circuits to obtain low microwave loss at X-band. Several liftoff techniques compatible with submicron device fabrication have been developed. These include a chlorobenzene (C6H5Cl) treatment of the photoresist and the use of a photoresist/aluminum layer to achieve negative sloped sidewalls. Both techniques have been used to define high yield 2 µm structures in GaAs.
{"title":"Advanced processing techniques for GaAs monolithic integrated circuits","authors":"M. Siracusa, Z. Lemnios, D. Maki","doi":"10.1109/IEDM.1980.189860","DOIUrl":"https://doi.org/10.1109/IEDM.1980.189860","url":null,"abstract":"This paper reports on the fabrication of an X-band GaAs microstrip amplifier as a test vehicle to establish a monolithic process capability. A variety of components are integrated on this circuit, including overlay and interdigital capacitors, via holes, air bridges and transmission lines. A novel geometry for overlay capacitors will be presented that has greatly improved yield and breakdown voltage over previous designs. Due to skin depth consideration, thick (∼ 2 µm) metallization layers are required on these circuits to obtain low microwave loss at X-band. Several liftoff techniques compatible with submicron device fabrication have been developed. These include a chlorobenzene (C6H5Cl) treatment of the photoresist and the use of a photoresist/aluminum layer to achieve negative sloped sidewalls. Both techniques have been used to define high yield 2 µm structures in GaAs.","PeriodicalId":180541,"journal":{"name":"1980 International Electron Devices Meeting","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122738359","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 : 1900-01-01DOI: 10.1109/IEDM.1980.189840
R.B. Wilson, R. Nelson, P. Wright
The fabrication procedure, electrical properties, and optical characteristics of InGaAsP buried-waveguide-heterostructure (BWH) lasers emitting at γ = 1.3 µm are described and compared with InGaAsP buried heterostructure (BH) and strip-buried heterostructure (SBH) lasers. Threshold currents as low as 140 mA have been achieved for the BWH structure which incorporates a high band gap quaternary waveguide layer adjacent to the active layer stripe. Measurements of the variation of the near-field and far-field patterns with stripe width indicate that the BWH device will operate in the fundamental transverse mode for stripe widths up to 5 µm.
{"title":"Electrical-optical characteristics of buried waveguide heterostructure InGaAsP injection lasers","authors":"R.B. Wilson, R. Nelson, P. Wright","doi":"10.1109/IEDM.1980.189840","DOIUrl":"https://doi.org/10.1109/IEDM.1980.189840","url":null,"abstract":"The fabrication procedure, electrical properties, and optical characteristics of InGaAsP buried-waveguide-heterostructure (BWH) lasers emitting at γ = 1.3 µm are described and compared with InGaAsP buried heterostructure (BH) and strip-buried heterostructure (SBH) lasers. Threshold currents as low as 140 mA have been achieved for the BWH structure which incorporates a high band gap quaternary waveguide layer adjacent to the active layer stripe. Measurements of the variation of the near-field and far-field patterns with stripe width indicate that the BWH device will operate in the fundamental transverse mode for stripe widths up to 5 µm.","PeriodicalId":180541,"journal":{"name":"1980 International Electron Devices Meeting","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122078157","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 : 1900-01-01DOI: 10.1109/IEDM.1980.189806
R. Payne, W. N. Grant, W. Bertram
{"title":"Elimination of latch up in bulk CMOS","authors":"R. Payne, W. N. Grant, W. Bertram","doi":"10.1109/IEDM.1980.189806","DOIUrl":"https://doi.org/10.1109/IEDM.1980.189806","url":null,"abstract":"","PeriodicalId":180541,"journal":{"name":"1980 International Electron Devices Meeting","volume":"251 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116806494","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 : 1900-01-01DOI: 10.1109/IEDM.1980.189966
K. Vaidyanathan, R. Jullens, C. Anderson, H. Dunlap
The high electron mobilities and wide bandgap of GaAs make it an attractive material for high speed, high temperature device applications. Integrated circuits employing MESFET devices have been fabricated. The speed, packing density, and drive capability advantages associated with bipolar devices make it attractive to investigate the feasibility of fabricating such devices in GaAs. In particular, if both bipolar and MESFET devices can be integrated into a planar IC process, the material properties of GaAs can be more fully exploited. In this paper we discuss the fabrication and properties of ion-implanted, planar bipolar n-p-n transistors in GaAs. The devices were fabricated by implanting the base and emitter regions into n-type epitaxial GaAs which acts as the collector. Using a thin evaporated metal layer as an implant mask, selective base regions were formed by Be-ion implantation. Silicon was then implanted to form the emitter region. The samples were annealed at 850°c for 30 minutes to electrically activate the impurities. A passivating dielectric layer (SixOyNz) was deposited by a plasma enhanced deposition process. Ohmic contacts to the collector and emitter regions were formed with Au/Ge:Ni while Ag:Mn ohmic contacts were made to the base region. Typical devices exhibited breakdown voltages in excess of 40V across the collector-base junctions and common emitter current gains of 8. Gains as high as 16 were observed. These results are extremely encouraging since structures were not designed for optimum performance. The leakage currents and the frequency response of these devices will be discussed.
{"title":"Planar, ion-implanted GaAs bipolar transistors","authors":"K. Vaidyanathan, R. Jullens, C. Anderson, H. Dunlap","doi":"10.1109/IEDM.1980.189966","DOIUrl":"https://doi.org/10.1109/IEDM.1980.189966","url":null,"abstract":"The high electron mobilities and wide bandgap of GaAs make it an attractive material for high speed, high temperature device applications. Integrated circuits employing MESFET devices have been fabricated. The speed, packing density, and drive capability advantages associated with bipolar devices make it attractive to investigate the feasibility of fabricating such devices in GaAs. In particular, if both bipolar and MESFET devices can be integrated into a planar IC process, the material properties of GaAs can be more fully exploited. In this paper we discuss the fabrication and properties of ion-implanted, planar bipolar n-p-n transistors in GaAs. The devices were fabricated by implanting the base and emitter regions into n-type epitaxial GaAs which acts as the collector. Using a thin evaporated metal layer as an implant mask, selective base regions were formed by Be-ion implantation. Silicon was then implanted to form the emitter region. The samples were annealed at 850°c for 30 minutes to electrically activate the impurities. A passivating dielectric layer (SixOyNz) was deposited by a plasma enhanced deposition process. Ohmic contacts to the collector and emitter regions were formed with Au/Ge:Ni while Ag:Mn ohmic contacts were made to the base region. Typical devices exhibited breakdown voltages in excess of 40V across the collector-base junctions and common emitter current gains of 8. Gains as high as 16 were observed. These results are extremely encouraging since structures were not designed for optimum performance. The leakage currents and the frequency response of these devices will be discussed.","PeriodicalId":180541,"journal":{"name":"1980 International Electron Devices Meeting","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128978481","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 : 1900-01-01DOI: 10.1109/IEDM.1980.189803
S. Mukherjee, R.E. Thomas, L. Haley, J. Koningstein, F. Adar
This paper reports on the results of applying ordinary Raman spectroscopy and a new narrow probing laser source to determine the degree of crystallinity obtained after laser annealing of amorphous silicon. Ordinary Raman spectroscopy over a large area annealed by multiple laser scans has been found to result in Raman spectra of variable band shapes and frequencies. These may be interpreted as superposition of amorphous (broad band centered around 480cm-1) and single crystal silicon spectra (sharp band centered at 523 cm-1) from the partially recrystallized regions. Probing selected locations in the annealed regions with a 1µm spot size laser source (using a Molecular Optical Laser Examiner, MOLE) has shown, for the first time, sharp bands being produced as low as 512 cm-1. Further annealing moved the narrow bands towards 523 cm-1, the centre frequency typical for ordinary Raman spectroscopy on single crystal silicon. Thus a combination of the two approaches allows examination of the effectiveness of laser annealing at both the macroscopic and microscopic level.
{"title":"Raman spectroscopy for evaluating laser annealed silicon layers","authors":"S. Mukherjee, R.E. Thomas, L. Haley, J. Koningstein, F. Adar","doi":"10.1109/IEDM.1980.189803","DOIUrl":"https://doi.org/10.1109/IEDM.1980.189803","url":null,"abstract":"This paper reports on the results of applying ordinary Raman spectroscopy and a new narrow probing laser source to determine the degree of crystallinity obtained after laser annealing of amorphous silicon. Ordinary Raman spectroscopy over a large area annealed by multiple laser scans has been found to result in Raman spectra of variable band shapes and frequencies. These may be interpreted as superposition of amorphous (broad band centered around 480cm-1) and single crystal silicon spectra (sharp band centered at 523 cm-1) from the partially recrystallized regions. Probing selected locations in the annealed regions with a 1µm spot size laser source (using a Molecular Optical Laser Examiner, MOLE) has shown, for the first time, sharp bands being produced as low as 512 cm-1. Further annealing moved the narrow bands towards 523 cm-1, the centre frequency typical for ordinary Raman spectroscopy on single crystal silicon. Thus a combination of the two approaches allows examination of the effectiveness of laser annealing at both the macroscopic and microscopic level.","PeriodicalId":180541,"journal":{"name":"1980 International Electron Devices Meeting","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129002190","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 : 1900-01-01DOI: 10.1109/IEDM.1980.189782
M. K. Scherba
Heat pipes, utilized in a high power space type traveling-wave tube, provide an efficient means of dispersing heat from areas of high concentration. Heat, generated in the region of the collector and output Circuit, is dispersed throughout the entire tube baseplate area by both longitudinal and transverse heat pipes contained in the baseplate. The results are lowered individual component temperatures and reduced thermal densities throughout the baseplate. The objective of this effort was to extend the power level of helix space tubes by combining a high efficiency cooling design approach with high efficiency electrical design techniques previously demonstrated on lower power space devices. These techniques include velocity tapering of the helix circuit, multi-stage depressed electron collection, low dielectric and conductive shield loading, and integral barrel focusing. A novel technique for transferring barrel heat to the baseplate is introduced. The tube delivers 300 watts of continuous wave RF output power at lower E-band frequencies. Saturated gain levels of 40 dB are obtained at an overall efficiency of 52%. The tube has been designed for conservative cathode loading and exhibits low operating temperature.
{"title":"Space tube with high efficiency cooling design approach","authors":"M. K. Scherba","doi":"10.1109/IEDM.1980.189782","DOIUrl":"https://doi.org/10.1109/IEDM.1980.189782","url":null,"abstract":"Heat pipes, utilized in a high power space type traveling-wave tube, provide an efficient means of dispersing heat from areas of high concentration. Heat, generated in the region of the collector and output Circuit, is dispersed throughout the entire tube baseplate area by both longitudinal and transverse heat pipes contained in the baseplate. The results are lowered individual component temperatures and reduced thermal densities throughout the baseplate. The objective of this effort was to extend the power level of helix space tubes by combining a high efficiency cooling design approach with high efficiency electrical design techniques previously demonstrated on lower power space devices. These techniques include velocity tapering of the helix circuit, multi-stage depressed electron collection, low dielectric and conductive shield loading, and integral barrel focusing. A novel technique for transferring barrel heat to the baseplate is introduced. The tube delivers 300 watts of continuous wave RF output power at lower E-band frequencies. Saturated gain levels of 40 dB are obtained at an overall efficiency of 52%. The tube has been designed for conservative cathode loading and exhibits low operating temperature.","PeriodicalId":180541,"journal":{"name":"1980 International Electron Devices Meeting","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130498964","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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