TEST METHOD OF RELIABILITY OF FERROELECTRIC CAPACITOR

摘要

PROBLEM TO BE SOLVED: To provide the test method of the reliability of a ferroelectric capacitor which is hardly influenced by difference in the polarization hysteresis characteristics between respective ferroelectric capacitors and has high precision. SOLUTION: A polarization hysteresis curve after the polarization toward a positive side and a polarization hysteresis curve after the polarization toward a negative side are repeatedly measured while an offset electric field is varied in a process P102 to obtain the offset electric field dependence of the nonvolatile polarization. Offset electric fields corresponding to the nonvolatile polarizations after being preserved for at least two different periods are obtained in a process P106. The approximate straight line of the preservation period dependence of the offset electric field is obtained by a method of least squares to calculate the offset electric field in a product guarantee period in a process P107. The nonvolatile polarization with the offset electric field in the product guarantee period is calculated in a process P108.