烘烤温度对溶胶-凝胶法制备镧掺杂钛酸铋薄膜结构与铁电性质的影响

采用溶胶-凝胶法，在保持薄膜结晶温度和有机物分解温度相同情况下，发现烘烤温度（即溶剂的挥发温度）对镧掺杂钛酸铋薄膜的晶体结构、表面形貌和铁电性质均产生重要影响.在较低烘烤温度下得到的薄膜（117）择优取向明显.但随着烘烤温度增加，薄膜的（117）择优取向逐渐减弱.薄膜的表面晶粒形貌则从棒状逐渐转变为盘状.还测量了薄膜的铁电性质，发现在250℃烘烤温度下得到的薄膜具有最大的剩余极化强度，2Pr为28.4μC/cm2.对实验现象进行了定性解释. 关键词： 溶胶-凝胶法 烘烤温度 铁电薄膜

The effect of baking temperature on the crystal structure and ferroelectric properties of Bi3.25La0.75Ti3O12 thin films prepared by sol-gel processing

The crystal structures, surface morphology and ferroelectric properties of Bi3.25La0.75Ti3O12 (BLT) thin films were found to be greatly affected by the baking temperature during sol-gel processing. At lower baking temperatures, the (117) orientation in the BLT thin film was preferred. However, with the increase of baking temperature, the (117) diffraction peak became weaker. In addition, the surface morphology of the films changed from rodlike to platelike. The ferroelectric properties were measured and it was found that the BLT thin film has the largest remnant polarization (2Pr) 284μC/cm2 prepared at a baking temperature of 250℃.