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室温下在ＭＯＤ法制备的ＰＬＴ铁电薄膜的样品上，观察不同电场强度下电流随时间的变化，根据电流的变化情况，把电场划分为弱、中、强三个区间。在弱场下，电流随时间的变化可用幂指数的衰减来模拟，而且衰减系数随场强的增加有减小的趋势。在中强场时，电流随时间在水平方向上上下波动。在强场下，电流随时间在波动的同时不断增大。因此在对不同区间电流随时间变化Ｉ（ｔ）曲线分析的基础上，确定某一电场强度下的漏导电流，作出了Ｉ－Ｖ曲线。同时发现不同配方，在相同工艺条件下的样品，其弱、中、强场的数值区间是不一样的，因此作出的Ｉ－Ｖ曲线也有所区别。对非欧姆区的导电机理用空间电荷限制电流（ＳＣＬＣ）模型和晶界限制电流（ＧＢＬＣ）模型来解释，同时对样品正向与反向的导电机理进行了对比研究。而且对热释电电流测量中有指导意义的薄膜充电后缓慢的放电过程进行了观察和分析
The PLT ferroelectric thin films prepared by MOD method were observed at room temperature under different electric field strengths with time. According to the change of electric current, the electric field was divided into weak, medium and strong regions. In the weak field, the change of the current over time can be simulated by the exponential decay, and the attenuation coefficient tends to decrease as the field strength increases. In the strong field, the current fluctuates horizontally over time. In a strong field, the current fluctuates with time while increasing. Therefore, based on the analysis of the curve of current I (t) in different intervals with time, the leakage current of a certain electric field is determined and the I-V curve is obtained. At the same time, it is found that the numerical ranges of weak, middle and strong fields of different formulations under the same process conditions are different, so the I-V curves made are also different. The conduction mechanism of the non-ohmic region is explained by the space charge-limited current (SCLC) model and the grain boundary current-limiting (GBLC) model. Meanwhile, the conducting mechanism of forward and reverse samples is compared. But also to observe and analyze the slow discharge process after the charge of thin film in the pyroelectric current measurement