Pt-ion-implantation-induced suppression of leakage conduction in Pt/Pb)(ZrxTi1−x)O3/Pt capacitors

Abstract

The effect of 1 MeV ion implantation on leakage conduction, dielectric and ferroelectric properties of the Pt/Pb(ZrxTi1−x)O3/Pt capacitors is studied for a wide range of implantation doses (1010–1016cm−2). It is shown that the implantation of Pt+, with an implant and vacancy profile peaking at the bottom interface and a dose within the range of 1013–1016cm−2, provokes a strong suppression of the leakage conduction and ferroelectric hysteresis. In addition, ion implantation results in a decrease of the static dielectric constant. Annealing of the specimens at 650°C restores the initial conduction and dielectric properties. The phenomena observed can be interpreted in terms of formation of a non-switching dielectric layer at the interface of the ferroelectric film. For doses ranging from 1013 to 1014cm−2 the specimen shows the behavior of a linear capacitor with dielectric constant of 120–270 and low level of leakage currents (about 10−9 A/cm2 at dc electric field of 150kV/cm). The results obtained indicate that ion bombardment of the ferroelectric film surface can be of practical interest for creation of high dielectric constant hysteresis-free low-leakage capacitor materials.