9702589 Fuierer The objective of this Faculty Early Career Development project is to advance the state-of-the-art and understanding of sol-gel chemistry routes to functional ceramic thin films by investigating the effects of the molecular structure of oligimers, derived from metalorganic precursors, on the ultimate crystallographic structure (orientation) of ceramic films upon heat treatment. Bismuth titanate will be used as the model ceramic material, due to its intrinsic structural anisotropy and its useful ferroelectric and piezoelectric properties. The experimental techniques employed will test the prediction that the homocondensation of Ti-O-Ti-O type molecular species and their subsequent deposition by spin coating on the surface of the substrate can lead to strongly-axis oriented films due to the similarity in atomic bonding in the a-b plane of crystalline bismuth titanate. These experiments will attempt to go beyond recent studies that illustrate the effect of oligomer molecular structure on other sintered microstructural features such as porosity and grain size. This will be accomplished primarily by two main ideas: (1) by taking a somewhat unorthodox approach of promoting homocondensation in mixed systems and allowing solutions to age for long periods of time, and (2) utilizing a new experimental technique of oxygen isotope nuclear magnetic resonance to determine the composition of the oligimer backbone by analyzing the chemical environment of the oxygen. The principal investigator intends to incorporate an increasing amount of chemical principles into classroom instruction of both undergraduate- and graduate-level materials courses. The principal investigator's long term career goals are to become an expert in the area of solution processing of anisotropic ceramic films, and to continuously strive toward effective teaching of the multidisciplinary field of materials science and engineering. %%% Proof of this phenomenon in sol-gel processing wi ll have significant implications by providing a means of obtaining textured films of other technologically important anisotropic materials without relying on special substrates for epitaxial growth. In addition, the research will yield important information about the kinetics of hydrolysis and condensation reactions in solution and crystallization processes in chemical thin films. Thus, the project is expected to contribute to the advance of improved materials for useful electronic, optical, and magnetic devices. The project is also aimed at helping to bridge the gap between chemistry and materials science and engineering by emphasizing the multidisciplinary aspects of these disciplines in the classroom. ***
