Journal of the Korean Physical Society

pISSN 0374-4884 eISSN 1976-8524


Application and Devices

Published online September 15, 2006    

Copyright © The Korean Physical Society.

Low-Temperature Sintering and Microwave Dielectric Properties of Ba3Ti4-xZrxNb4O21 Ceramics with the Substitution of Zr for Ti

Won-Jun Ko, Young-Jin Choi, Jeong-Hyun Park, Jae-Hwan Park and Jae-Gwan Park

J. Korean Phys. Soc. 49(3), 1234 (2006)


The effects of substitution of Zr for Ti on the microwave dielectric properties of Ba$_3$Ti$_{4-x}$Zr$_x$Nb$_4$O$_{21}$ (0 $leq$ $x$ $leq$ 4) ceramics were studied. The dielectric constant and the quality factor of the Ba$_3$Ti$_{4-x}$Zr$_x$Nb$_4$O$_{21}$ ceramics decreased slightly with increasing composition $x$, which could be attributed to a change in the ion polarization and the microstructure caused by the substitution of Zr for Ti. The temperature coefficient of the resonant frequency of Ba$_3$Ti$_{4-x}$Zr$_x$Nb$_4$O$_{21}$ ceramics changed from +50 to +100 ppm/$^circ$C. Meanwhile, Ba$_3$Ti$_{4-x}$Zr$_x$Nb$_4$O$_{21}$ ($x$ = 1) with a 5 wt\% glass frit was densified at a relatively low sintering temperature below 900 $^circ$C. Ba$_3$Ti$_{4-x}$Zr$_x$Nb$_4$O$_{21}$ ($x$ = 1) ceramics with 7 wt\% glass sintered at 875 $^circ$C exhibited good microwave dielectric properties: k = 52, Q$ imes$f = 3000 GHz, and $ au_f$ = +5 ppm/$^circ$C.