文献类型：期刊文献

英文题名：The preparation and ferroelectric properties of defect-free ultrathin films of vinylidene fluoride oligomer

作者：Xu, Haisheng[1];Li, Guobing[1];Zhang, Yanni[1];Zhang, Xiuli[1,2];Gu, Yingjun[1];Shen, Dong[1];Meng, XiangJian[3]

机构：[1]E China Univ Sci & Technol, Dept Phys, Shanghai 200237, Peoples R China;[2]Shanghai Univ Engn Sci, Sch Fundamental Studies, Shanghai 201620, Peoples R China;[3]Chinese Acad Sci, Shanghai Inst Tech Phys, Natl Lab Infrared Phys, Shanghai 200083, Peoples R China

年份：2010

卷号：107

期号：3

外文期刊名：JOURNAL OF APPLIED PHYSICS

收录：;EI(收录号：20100812727219);WOS:【SCI-EXPANDED(收录号:WOS:000274517300080)】；

基金：This work was supported by Science and Technology Commission of Shanghai Municipality under Grant No. 07pj14029. We thank Kunshan Hisense Electronic Co. Ltd. for providing the oligomer.

语种：英文

外文关键词：annealing; dielectric polarisation; ferroelectric coercive field; ferroelectric switching; ferroelectric thin films; polymer blends; polymer films; random-access storage; vapour deposited coatings

摘要：The ultrathin, defect-free ferroelectric films of vinylidene fluoride oligomer were fabricated by vapor deposition. A narrow substrate temperature window was found to get high quality ferroelectric films. Ferroelectric phase was obtained when the substrate temperature was -90 degrees C. The ferroelectric phase is stable at room temperature, even after annealing at 120 degrees C for 30 min. A full memory stack based on the ferroelectric VDF oligomer may work as nonvolatile random access memory with superhigh density due to the smaller crystal grain comparing with that of poly(vinylidene fluoride-trifluoethylene) [P(VDF-TrFE)] copolymers. The cell shows prominent ferroelectric properties even as the thickness of VDF oligomer film is down to 60 nm with a coercive field of 95 MV/m and a remnant polarization of 125 mC/m(2). After 1x10(5) cycles of switching, no ferroelectric degradation was observed, the ratio of polarization before and after fatigue is close to 1, which is in contrast to P(VDF-TrFE) thin film where the ferroelectric degradation starts after 1x10(4) times of switching. The pulse polarization test shows that switching takes place as fast as a few microseconds to reach 90% of the saturated polarization. At 60 degrees C and 8 V operating voltage, the cell still shows excellent fatigue property.