Microstructural Studies on the Low-Temperature Crystallization Process of Strontium Bismuth Tantalate Thin Films

• Published in: Journal of the American Ceramic Society Vol. 87; no. 1; pp. 138 - 143
• Main Authors: Ricote, Jesús, Calzada, M. Lourdes, González, Ana, Ocal, Carmen
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.01.2004; Blackwell; Wiley Subscription Services, Inc
• Subjects: Ceramics; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Crystallization; Exact sciences and technology; Grain; Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids); Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Temperature; Thin film structure and morphology; Atomic force microscopy; Chemical solution; Grain growth; Electron diffraction; Crystallization; Composition effect; Perovskites; Experimental study; Bismuth Tantalates; Bismuth Strontium Tantalates Mixed; Thin films; Thickness; Transmission electron microscopy; Ferroelectric materials; Spin-on coating; Strontium Tantalates; Microstructure; Growth from solution; Low temperature
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1551-2916.2004.00138.x

The preparation of strontium bismuth tantalate (SBT) thin films at low temperatures for electronic applications is at present the subject of intense study. However, the microstructural evolution of these films has not been extensively reported, despite its importance in the determination of the final properties of the film. In this work, we study SBT thin films with various nominal compositions obtained by the crystallization at 650°3C of spin‐coated solutions on a silicon‐based substrate. Both the formation of the perovskite phase and the evolution of the grains are analyzed, with special attention to the formation of platelet‐like grains. A process of coalescence of initially round grains is proposed to explain the grain growth in this system. We also show that the use of a preannealing step inhibits the grain growth and, therefore, should be avoided. The role that the film thickness plays in the development of large grains is discussed.