Eur. Phys. J. B 41, 301-306 (2004)
https://doi.org/10.1140/epjb/e2004-00321-8

Temperature stable low loss ceramic dielectrics in (1-x)ZnAl₂O₄-xTiO₂ system for microwave substrate applications

¹ Ceramic Technology Division, Regional Research Laboratory, Trivandrum 695 019, India
² Department of Electronics, Cochin University of Science and Technology, Cochin 682 022, India

Corresponding author: ^a mailadils@yahoo.com

Received: 29 January 2004
Published online: 21 October 2004

Abstract

The microwave dielectric properties of ZnAl₂O₄ spinels were investigated and their properties were tailored by adding different mole fractions of TiO₂. The samples were synthesized using the mixed oxide route. The phase purity and crystal structure were identified using X-ray diffraction technique. The sintered specimens were characterized in the microwave frequency range (3–13 GHz). The ZnAl₂O₄ ceramics exhibited interesting dielectric properties (dielectric constant (, unloaded quality factor ( at 12.27 GHz and temperature coefficient of resonant frequency ( ppm/C). Addition of TiO₂ into the spinel improved its properties and the approached zero for 0.83ZnAl₂O₄-0.17TiO₂. This temperature compensated composition has excellent microwave dielectric properties (, at 10.075 GHz) which can be exploited for microwave substrate applications.