Pzt Thin Film Interface Passivation Layer Capacitance Test Method

Ferroelectric thin films have attracted great attention for potential application in ferroelectric random access memory,among which lead zirconium titanate(PZT) thin films are the most popular material and are most intensively investigated because PZT has advantages such as low processing temperature(as low as 450℃) and huge remnant values(as high as 60μc/cm²).However,although PZT has such excellent characteristics,some serous drawbacks such as fatigue,retention and imprint yoked its application and development in memories.The three disadvantages of PZT,even in other ferroelectric thin film materials,are like the dark clouds over the sky of ferroelectric random access memory.If we do not drive them away from the road,the ferroelectric random access memory will be the waste paper in the rubbish bin of the science history.To get over the three main barriers of the application of PZT thin solid films,many ameliorative projects were proposed to improve the performances or even substitute for PZT thin solid films.There are three main solutions:1,doping some metal elements into PZT could do great fine work into the fatigue and the imprint behavior of PZT thin solid films,like Nb and Si.2,the layered-bismuth ferroelectric material has attracted promising researches according to its excellent fatigue resistance,like SBT,BLT.3, some metal oxide electrode and perovskite structure compound could inhibit fatigue effectively,like IrO₂,LaNiO₃.Besides the chemical and structural improvement,it is commonly understand that the presence of a thin passive layer in a ferroelectric capacitor can substantially influence its switching characteristics.The thinner the film the greater effect is expected.The aim of the present article is to present a novel methodology to extract the capacitance of the interfacial layers in the films with different thicknesses and to analyze the nonlinear capacitance behavior of the interfacial layers with respect to applied voltages and temperatures.Finally,the technique is compared with the conventional extrapolation method for the elucidation of interfacial physics.