Open AccessResonant frequency temperature stability of CaTiO3 based microwave dielectric ceramics
Author(s) -
Jie Shen,
Jing Zhou,
Shi Guo-Qiang,
Wayne Yang,
Hanxing Liu,
Wen Chen
Publication year - 2013
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.62.117702
Subject(s) - materials science , ceramic , microwave , dielectric , stability (learning theory) , optoelectronics , engineering physics , composite material , telecommunications , physics , engineering , computer science , machine learning
The determinants of resonant frequency temperature coefficient (τf) have been analyzed by the approximate treatment of Clausius-Mossotti equation. It is suggested that the value of τf can be adjusted by changing the contribution proportion of ionic polarization or electronic polarization for the dielectric constant. Results of electronic structure calculation and tolerance factor analysis show that B-site substitution of CaTiO3 with (Zn1/3Nb2/3)4+ could turn the value of τf from positive to negative, by enhancing the covalency in the BO6 octahedron and improving the contribution proportion of electronic polarization. Ca[(Zn1/3Nb2/3)xTi(1-x)]O3 dielectric ceramics were prepared by solid-state reaction method with niobate as precursor. Results of structure analysis and property measurement conform to the theoretical analysis. The Ca[(Zn1/3Nb2/3)0.7Ti0.3]O3 dielectric ceramic with near-zero τf was obtained.