Low-loss Ca{sub 5-x}Sr{sub x}A{sub 2}TiO{sub 12} [A=Nb,Ta] ceramics: Microwave dielectric properties and vibrational spectroscopic analysis

Journal Article · Sun May 15 00:00:00 EDT 2005 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1897065· OSTI ID:20709661

Bijumon, Pazhoor Varghese; Sebastian, Mailadil Thomas; Dias, Anderson; Moreira, Roberto Luiz; Mohanan, Pezholil ^[1]

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1. Ceramic Technology Division, Regional Research Laboratory, Trivandrum 695 019 (India)

Complex perovskite-type Ca{sub 5-x}Sr{sub x}A{sub 2}TiO{sub 12} [A=Nb,Ta] (0{<=}x{<=}5) ceramics were prepared by conventional solid-state ceramic route. The crystal structure, microwave dielectric properties, and vibrational spectroscopic characteristics of these materials are reported. The structure and microstructure were investigated by x-ray diffraction and scanning electron microscopy techniques. The microwave dielectric properties were measured in the 3-5-GHz frequency range by the resonance method. Structural evolutions from orthorhombic to an averaged pseudocubic phase, with associated changes in dielectric properties, were observed as a function of composition. The structure-property relationships in these ceramics were established using Raman and Fourier transform infrared spectroscopic techniques. Raman analysis showed characteristic bands of ordered perovskite materials, with variation in both intensity and frequency as a function of composition.

• OSTI ID: 20709661
• Journal Information: Journal of Applied Physics, Vol. 97, Issue 10; Other Information: DOI: 10.1063/1.1897065; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CALCIUM COMPOUNDS
CERAMICS
DIELECTRIC MATERIALS
FOURIER TRANSFORM SPECTROMETERS
GHZ RANGE 01-100
INFRARED SPECTRA
MICROSTRUCTURE
MICROWAVE RADIATION
NIOBIUM COMPOUNDS
PERMITTIVITY
PEROVSKITE
PHASE TRANSFORMATIONS
RAMAN SPECTRA
SCANNING ELECTRON MICROSCOPY
STRONTIUM COMPOUNDS
TANTALUM COMPOUNDS
TITANATES
X-RAY DIFFRACTION