Ferroelectric switching, memory retention and endurance properties of very thin PZT films

Abstract

Successful ferroelectric polarization and domain switching have been demonstrated in thin leadzirconate-titanate (PZT) films, less than 500A, prepared by the sol-gel technique. 1 In this paper, the ferroelectric switching, memory retention and endurance properties of these thin films, ranging in thickness from 425A to 1500A with a Zr/Ti ratio of 50/50, were investigated. A remanent polarization of 27 μC/cm2 was observed on a 650A thick capacitor with a saturation voltage of 3 volts. A switching speed of 10.8 ns was measured for a 600A thick, 25 × 25 μm capacitor. A 1000A thick, 100 × 100 μm capacitor showed no data loss after 1650 hours of memory retention. The projected life for both 1000A and 650A thick, 40 × 40 μm capacitors is estimated to be longer than 1 × 1010 switching endurance cycles. Detailed measurements and experimental results will be described.