Effects of thickness on the electrical properties of metalorganic chemical vapor deposited Pb(Zr, Ti)O3 (25–100 nm) thin films on LaNiO3 buffered Si

Abstract

Pb(Zr, Ti)O 3 (PZT) thin films with (100) preferred orientation were prepared using metalorganic chemical vapor deposition on LaNiO3 (LNO) buffered platinized Si with thickness varying from 25–100 nm. The dependence of electrical properties of PZT films on thickness was studied using several techniques, including polarization–electric field (P–E), temperature variable current–voltage (I–V), and capacitance–voltage (C–V) measurements. Because of the formation of Schottky barriers at ferroelectric/electrode interfaces, built-in electric fields are present. A progressive increment in carrier concentration and interfacial built-in electric field versus reducing PZT film thickness was observed, which is believed to be a dominant factor controlling the measured dielectric/ferroelectric properties. The higher built-in electric field in thinner PZT films would pin the dipoles at the interfacial region and retard the response of dipoles to the external electric field.