Thermal aging effect in poled ferroelectric SrBi2(Ta,Nb)(2)O-9 capacitors

Changes In the electrical properties of poled ferroelectric SrBi2(Ta,Nb)(2) O-9 (SBTN) thin-film capacitors caused by high;temperature storage were stu died. Current-voltage (J-V) characteristics of SBTN capacitors before and a fter high-temperature storage indicated that the current in SBTN is predomi nantly carried by electrons, and limited by electrode interfaces. The volta ge shift ih the polarization-voltage (P-V) curve caused at high temperature s was ascribed to a bulk effect because there were no definite changes in t he interface-limited J-V characteristics before and after high-temperature Storage. Assuming the pinning of domains by capturing electrons emitted fro m traps distributed in the energy gap, we describe the decay in switchable polarization with the power of time. The activation energy for the decay in switchable polarization associated with electron capture was determined to be 0.23 eV based on the: temperature dependence of the decay in switchable polarization.