Phase development and ferroelectric properties of lead zirconate titanate thin films prepared from a triol sol-gel route

The crystallization temperature and ferroelectric properties of PbZr (0.53) Ti O-0.47(3) Rims prepared using a recently developed triol sol-gel route were investigated fur coatings deposited on platinised silicon substrates. For these 0.4 pm single-layer films, the onset of crystallization, to a mix ture of perovskite and pyrochlore/fluorite intermediate phases, occurred at oa. 500 degreesC, but the films were not ferroelectric. Although samples h eated at 550 degreesC showed only the perovskite phase in XRD patterns, hea ting at 580 degreesC was required to produce films which displayed typical ferroelectric P-E hysteresis loops, giving a remanent polarisation, Pr, of 22 muC cm(-2) and coercive field, Ec, of 40 kV cm(-1). There was little cha nge in Pr and Ec values when the final decomposition step was carried out a t higher temperatures. up to 700 degreesC. Films displayed a mixture of [11 1] and [100] orientation, the extent of which varied with final decompositi on temperature. (C) 2001 Elsevier Science Ltd. All rights reserved.