不同极化态下有机铁电膜微观振动特性的AFM研究  

AFM study on the local vibratory properties in ferroelectric vinylidene fluoride and trifluoroethylene copolymer films at different polarized states

作　　者：朱国栋[1] 曾志刚[1] 张莉[1] 沈淼[1] 严学俭[1] 

机构地区：[1]复旦大学材料科学系,上海200433

出　　处：《功能材料与器件学报》2007年第2期159-163,共5页Journal of Functional Materials and Devices

摘　　要：借助原子力显微镜优异的空间分辨能力和锁相放大技术,实验研究了有机铁电薄膜在不同极化状态下的微观振动特性。负极化态时,薄膜表面振动与驱动电压呈线性且同相;而正极化态时,表面振动与驱动电压依然呈线性,但两者间存在180°相差。实验中清楚地观测到局域振动畴、非振动畴以及振动振幅相对较小的振动畴三者间的共存。本工作探讨了非活性铁电畴存在的可能性,并认为是陷阱电荷的箝制作用限制了铁电畴的活性。By the combination of Atomic Force Microscope and lock - in amplifier, local piezoelectric properties in ferroelectric vinylidene fluoride and trifluoroethylene copolymer films at different polarized states were studied. The results indicate that, at the negatively polarized state, the vibrations on film surface are linearly dependent on the driving voltage, while, at the positively polarized state, the vibrations are also linearly dependent, but with a phase delay of 180o. The coexistence of the local vibratory domains, non- vibratory domains and vibratory domains with much smaller amplitudes is obviously observed. It is regarded that the existence of in - active ferroelectric domains should be contributed to the origin of non - vibratory domains and these in - active domains are pinned by trapped charges.

关 键 词：P(VDF-TrFE) 原子力显微镜 压电性 陷阱电荷 

分 类 号：O484.4[理学—固体物理] O482.41[理学—物理]