PZT铁电薄膜纳米尺度畴结构的扫描力显微术研究

SFM investigation of nanoscale domain structure in ferroelectric PZT thin films

利用扫描力显微术中压电响应模式原位研究了 (111)择优取向的PZT6 0 4 0铁电薄膜的纳米尺度畴结构及其极化反转行为 .铁电畴图像复杂的畴衬度与晶粒中的畴排列和晶粒的取向密切相关 .直接观察到极化反转期间所形成的小至 30nm宽的台阶结构 ,该台阶结构揭示了 (111)取向的PZT6 0 4 0铁电薄膜在极化反转期间其畴成核与生长机理主要表现为铁电畴的纵向生长机理 .

Nanoscale domain structures and polarization reversal behaviour in (111)-oriented PZT60/40 thin film were investigated in-situ with scanning force microscopy piezoresponse mode. Complex domain contrast is related to the arrangement of domains in grains and to the orientation of the grains in the film. The step structure of similar to 30 nm in width was directly observed, which was formed during the polarization reversal process. The presence of the step structures reveals that the forward domain growth mechanism prevails in the polarization switching process of PZT60/40 thin films.