Crystallization and ferroelectric behavior of sputter deposited PZT using a target containing excess Pb and O contents

The effect of excess Pb and O content on the formation of PZT films with perovskite phase and their electrical properties has been investigated. PZT films were sputter-deposited from a target containing 50% excess Pb and O on Pt/Ti/SiO2/Si substrates. When PZT films were deposited at room temperature, they crystallized with pyrochlore and perovskite phases after rapid thermal annealing (RTA) treatments at 520 and 700 degrees C, respectively. But with substrate-heating at 520 degrees C, the PZT films crystallized directly with the perovskite phase. After RTA treatments at 600 and 700 degrees C of the PZT films deposited at 520 degrees C, a reduction of the coercive field (E-c) and amelioration of the fatigue property were found. An improvement of the I-V characteristic was also observed. This amelioration of ferroelectric properties of high temperature annealed PZT films were explained using a 'space charge layer model'. (C) 1999 Elsevier Science S.A. All rights reserved.