A New Metastable Thin-Film Strontium Tantalate Perovskite

• Published in: Journal of the American Ceramic Society Vol. 82; no. 8; pp. 2101 - 2105
• Main Authors: Rodriguez, Mark A., Boyle, Timothy J., Hernandez, Bernadette A., Tallant, David R., Vanheusden, Karel
• Format: Journal Article
• Language: English
• Published: Westerville, Ohio American Ceramics Society 01-08-1999; Blackwell; Wiley Subscription Services, Inc
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; 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); Thin film structure and morphology; Raman spectra; Inorganic compounds; Metastable phases; Ternary compounds; Chemical method; Perovskites; XRD; Experimental study; Thin films; Unit cell; Crystal growth from solutions; SEM; Strontium Tantalates; Permittivity; EPR spectra
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1151-2916.1999.tb02047.x

A novel Sr‐Ta‐O perovskite phase has been synthesized by a chemical preparation route and crystallized on Pt‐coated SiO2/Si substrates at ∼800°C. The phase was isolated as a thin film only (not as a polycrystalline powder) and is likely metastable. SEM, EDS, XRD, EPR, and Raman analyses suggest this phase is cation‐deficient, having the formula SrxTaxO3 (x∼ 0.85). X‐ray Rietveld analysis indicates the structure to be a simple‐cubic perovskite‐type lattice; Pm3m space group, a= 3.955(2) Å, V= 61.86 Å3, Z= 1. Electrical property measurements recorded a dielectric constant k of ∼16 with a tan delta of 0.04.