Effects of Ba(Mg1/3Ta2/3)O3 buffer layer on the fatigue behavior in Pb(Zr0.52Ti0.48)O3 thin films

Abstract

In this paper, Pb(Zr0.52Ti0.48)O3 (PZT) thin films were deposited on Pt/Ti/SiO2/Si substrates via sol–gel method by using Ba(Mg1/3Ta2/3)O3 (BMT) thin film as buffer layer. The effects of BMT buffer layer on the fatigue behavior in PZT thin films were investigated. After 1.04 × 108 reversal cycles, the remnant polarization value of buffered PZT thin films decreases only 12.1 %, while it decreases 58.2 % in PZT thin films. The results reveal that BMT buffer layer can greatly improve the fatigue properties of PZT thin films, which are related to the oxygen vacancies accumulation. The oxygen vacancies accumulation can reduce the electric field across the PZT layer and inhibit the motion of domain. BMT buffer layer can modify the PZT/Pt interface, which can reduce mobility of oxygen vacancies from PZT thin films to PZT/Pt interface. Moreover, the energy bandgap of PZT films (Eg = 3.6 eV) is similar to that of BMT films (Eg = 3.7 eV), which can minimize the oxygen vacancies accumulation. Furthermore, BMT buffer layer can reduce the residual stress, which can reduce suppression of domain switching.