The dependence of polarization fatigue on crystallinity of vinylidene fluoride and trifluoroethylene copolymer films was studied.Experimental data indicated that the higher the crystallinity of the film was,the slower...The dependence of polarization fatigue on crystallinity of vinylidene fluoride and trifluoroethylene copolymer films was studied.Experimental data indicated that the higher the crystallinity of the film was,the slower the fatigue rate of the film became.A possible explanation was put forward,and it was regarded that the space charges,trapped at the boundaries of crystallites and/or captured by the defects lying both in amorphous and crystalline phases,should make the major contribution to polarization fatig...展开更多
This paper investigates the influences of polarization fatigue on remanent polarization and switching time by pulse train measurements in ferroelectric poly（vinylidene fluoride （78%） and trifluoroethylene （22%））...This paper investigates the influences of polarization fatigue on remanent polarization and switching time by pulse train measurements in ferroelectric poly（vinylidene fluoride （78%） and trifluoroethylene （22%）） thin films. Fatigue was carried out by a series of bipolar switching pulses with constant pulse width （on-time） and various interval times between pulses （off-time）. The experimental observations indicated that the off-time period showed no obvious influence on fatigue rate and the switching time increased with the increase of fatigue cycles. The origination of these phenomena was discussed according to the charge injection model.展开更多
Organic ferroelectric field-effect transistors （OFeFETs） are regarded as a promising technology for low-cost flexible memories. However, the electrical instability is still a critical obstacle, which limits the comm...Organic ferroelectric field-effect transistors （OFeFETs） are regarded as a promising technology for low-cost flexible memories. However, the electrical instability is still a critical obstacle, which limits the commercialization process. Based on already established models for polarization in ferroelectrics and charge transport in OFeFETs, simulation work is performed to determine the influence of polarization fatigue and ferroelectric switching transient on electrical characteristics in OFeFETs. The polarization fatigue results in the decrease of the on-state drain current and the memory window width and thus degrades the memory performance. The output measurements during the ferroelectric switching process show a hysteresis due to the instable polarization. In the on/off measurements, a large writing/erasing pulse frequency weakens the polarization modulation and thus results in a small separation between on- and off-state drain currents. According to the electrical properties of the ferroelectric layer, suggestions are given to obtain optimal electrical characterization for OFeFETs.展开更多
基金supported by Science and Technology Commission of Shanghai Municipality(No.0652NM028)ShanghaiLeading Academic Discipline Project(No.B113)+1 种基金National Natural Science Foundation of China(No.10804020)Specialized Research Fund for the Doctoral Program of Higher Education of China(No.200802461088).
文摘The dependence of polarization fatigue on crystallinity of vinylidene fluoride and trifluoroethylene copolymer films was studied.Experimental data indicated that the higher the crystallinity of the film was,the slower the fatigue rate of the film became.A possible explanation was put forward,and it was regarded that the space charges,trapped at the boundaries of crystallites and/or captured by the defects lying both in amorphous and crystalline phases,should make the major contribution to polarization fatig...
基金Project supported by the National Natural Science Foundation of China (Grant No. 10804020)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 200802461088)
文摘This paper investigates the influences of polarization fatigue on remanent polarization and switching time by pulse train measurements in ferroelectric poly（vinylidene fluoride （78%） and trifluoroethylene （22%）） thin films. Fatigue was carried out by a series of bipolar switching pulses with constant pulse width （on-time） and various interval times between pulses （off-time）. The experimental observations indicated that the off-time period showed no obvious influence on fatigue rate and the switching time increased with the increase of fatigue cycles. The origination of these phenomena was discussed according to the charge injection model.
基金supported by the National Key Technologies R&D Program,China(Grant No.2009ZX02302-002)the National Natural Science Foundation of China(Grant Nos.61376108,61076076,and 61076068)+2 种基金NSAF,China(Grant No.U1430106)the Science and Technology Commission of Shanghai Municipality,China(Grant No.13NM1400600)Zhuo Xue Plan in Fudan University,China
文摘Organic ferroelectric field-effect transistors （OFeFETs） are regarded as a promising technology for low-cost flexible memories. However, the electrical instability is still a critical obstacle, which limits the commercialization process. Based on already established models for polarization in ferroelectrics and charge transport in OFeFETs, simulation work is performed to determine the influence of polarization fatigue and ferroelectric switching transient on electrical characteristics in OFeFETs. The polarization fatigue results in the decrease of the on-state drain current and the memory window width and thus degrades the memory performance. The output measurements during the ferroelectric switching process show a hysteresis due to the instable polarization. In the on/off measurements, a large writing/erasing pulse frequency weakens the polarization modulation and thus results in a small separation between on- and off-state drain currents. According to the electrical properties of the ferroelectric layer, suggestions are given to obtain optimal electrical characterization for OFeFETs.
基金The Ministry of Science and Technology of China through a 973 Project(2012CB619401)Fund of National Key laboratory of Shock Wave and Detonation Physics(LSD2012003)"One Thousand Youth Talents"Program
