Structural and Dielectric Characterization of AgNbO₃-Based Thin Films from Chemical Solution Deposition

Dielectric capacitors for energy storage applications have garnered significant attention due to their fast charge-discharge rates, high volumetric energy and power densities, and excellent stability and reliability, making them ideal for various modern electronics and electrical systems. AgNbO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> is an antiferroelectric material with promising dielectric and energy storage properties. However, thin films based on AgNbO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> face challenges in terms of phase purity and achieving a dense microstructure. In this work, we report on AgNb<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1-x</inf>Ta<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> thin films prepared via chemical solution deposition using two different solvents to reduce porosity, enhance densification, and produce smooth, crack-free films. A shift in relative permittivity towards room temperature with increasing Ta substitution was observed, aligning well with reported phase transition temperatures in bulk ceramics. Additionally, an excess of Ag was successfully used to eliminate natrotantite-like secondary phases in highly Ta-substituted thin films, leading to phase-pure AgNb<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1-x</inf>Ta<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> thin films with improved dielectric properties.