【摘要】 报道了半花菁染料LB膜铁电性与膜厚度的依赖性.根据所测得的电滞回线发现,矫顽电场(Ec)随薄膜厚度(以薄膜的层数N表示)的增加而减少,在薄膜厚度为30～200nm的范围内,它们之间的关系可用幂指数公式表示为Ec∝N-4/3,这种关系与其它传统的无机铁电材料完全相同.通过样品介电和铁电性能的测量,以存贮元件的物理参量-优值(Ps/εrEC)作为参比标准,可得铁电半花菁染料LB膜的最佳厚度为60nm,且其优值的数值与偏氟乙烯-三氟乙烯共聚物P(VdF-TrFE)(n:n=70:30)的优值数值处在同一数量级上.更多还原

【Abstract】 Typical ferroelectricity in Langmuir Blodgett multilayers prepared from hemicyanine dyes has been demonstrated by observed ferroelectric hysteresis loop. Their ferroelectric properties are found to be thickness dependent. The coercive field decreased with increasing film thickness monotonously and may be approximated by a power law Ec∝ N- 4/3 in the range from 30 to 200 nm, which is coincident with other conventional ferroelectric materials. The optimum thickness of hemicyanine LB multiplayer is about 60 nm and their optimum value as ferroelectric storage devices has the same order of magnitude as P(VdF TrEE)(n :n=70 :30).更多还原