Self-assembly of ultrathin composite TiO2/polymer films

A wet layer-by-layer self-assembly of composite TiO2/polymer films on Si an d Al2O3/Al, substrates has been studied by AFM, STM, and ellipsometry techn iques. The quality of the first adsorbed TiO2 layer has been found to be th e governing factor in multilayer film growth. The first layer consists of s ingle particles and particle agglomerates 30-120 nm wide The surface covera ge in the layer is determined by the chemical composition of the substrate surface and water pH in post-adsorption rinsing procedure. Well-packed TiO2 /polymer film completely covering the surface has been prepared in five ads orption cycle on Al2O3Al substrate. The film remained crack-free after heat treatment at 300 degrees C. I-V curves measurement reveals high resistivit y (R similar to 10(10) O in the voltage range from -2 to +3 V) of TiO2/poly mer films prepared in ten adsorption cycles. (C) 1999 Elsevier Science S.A. All rights reserved.