Microstructures and optical properties of solgel derived Ba_0.9Sr_0.1TiO₃ thin films formed by different annealing process

Abstract

We investigated the effect of annealing process on microstructures and optical properties of the sol-gel derived Ba_0.9Sr_0.1TiO₃ (BST) films. The BST films, fabricated by layer-by-layer high-temperature (⩾ 650 °C) annealing process, had laminated structures consisting of alternating dense and porous BST layers, and exhibited excellent optical performance as Bragg reflectors. The Bragg reflection characteristic can be enhanced with increasing annealing temperature. Those BST films fabricated at temperatures lower than 650°C displayed uniform cross-sectional morphologies even treated at a higher temperature. The difference in the microstructures of the BST thin films was also discussed.

Keywords

annealing process / BST films / microstructures / optical properties

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