INFLUENCE OF ANNEALING ON THE FERROELECTRIC PROPERTIES OF PT PB(ZR,TI)O-3/PT THIN-FILM CAPACITORS/

The deformation in the hysteresis loop of Pt/Pb(Zr,Ti)O-3/Pt capacitor s has been investigated by varying the annealing temperature after pat terning the top sputter-deposited electrode using reactive ion etching (RIE) with Ar gas. It was observed that as-patterned capacitors were positively poled by the de plasma potential during RIE of Pt. Voltage shift and slant in the hysteresis loop are found to be due to space ch arges trapped at domain boundaries during both sputtering and RIE rath er than a nonferroelectric second phase. As Zr:Ti ratio decreases, int ernal bias field increases, and annealing temperature, at which maximu m in polarization occurs, also increases due to lower permittivity and higher Curie temperature. (C) 1997 Elsevier Science S.A.