Texture Development, Microstructure Evolution, and Crystallization of Chemically Derived PZT Thin Films

Two solution-based methods, metallo-organic decomposition and sol–gel processes, were used to study the effects of precursor solution type on the microstructure evolution and texture development of oriented PZT films. Microstructure development and perovskite content are strongly dependent on the heating rate. Fast heating rate forms a dense fine-grained microstructure with (111) orientation. Intermediate-temperature pyrolysis followed by a fast heating rate forms clustered or island structures of submicrometer grains with (100) orientation. Intermediatetemperature pyrolysis followed by a very slow heating rate forms larger spherical rosettes with random orientations. Pt5–7Pb is a (111) textured transient intermetallic phase that nucleates PZT(111) texture. PbO is a (001) textured layer compound that nucleates PZT(100) texture. The texture selection of PZT films is independent of precursor systems but sensitive to the film thickness especially when sol–gel precursors and oxidizing atmosphere are used. Correlation and comparison of oriented sol–gel and MOD PZT films with electrical properties are also made.