The effect of leak resistance and linear capacitance must be compensated in the hysteresis measurement of ferroelectric film.This paper adopted improved Sawyer-Tower circuit and analyzed the influence to the spontaneous polarization introduced by leak resistance and linear capacitance.It was found that in sinusoidal electric field the leak resistance added an odd symmetrical voltage component to polarized voltage about the saturated polarization point, and linear capacitance brought in an even symmetrical voltage component. Two equations for calculating the leak resistance and linear capacitance were derived. Sample only three couples of the driving voltage and polarized voltage at the peak of saturated polarization and its adjacent left and right point, the value of leak resistance and linear capacitance can be determined immediately, and then followed by fast numerical compensation of hysteresis.Time for determining leak resistance and linear capacitance is 2% of that using dichotomy.%测量铁电薄膜电滞回线必须补偿漏电阻和线性电容的影响.本文采用Sawyer-Tower改进电路,分析了在正弦激励电场下漏电阻和线性电容对自发极化的影响,指出二者分别关于饱和极化点奇对称和偶对称;利用正峰值饱和极化点及其前后相邻两点共3对激励电压和极化电压,推导出漏电阻和线性电容计算公式,进而可实现电滞回线快速数值补偿.本算法漏电阻和线性电容的计算时间仅为二分法用时的2%.
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