The behavior of high frequency tunable dielectric resonator antenna (DRA) with the addition of excess Fe^sub 2^O3 in Y^sub 3^Fe^sub 5^O^sub 12^ (YIG) formulation

• Published in: Journal of materials science. Materials in electronics 2014-01, Vol.25 (1), p.560
• Main Authors: Ali, Wan Fahmin, Faiz, Wan, Othman, Mohamadariff, Ain, Mohd Fadzil, Abdullah, Norazharuddin Shah, Ahmad, Zainal Arifin
• Format: Article
• Language: English
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-013-1624-1

This manuscript discusses the potential of yttrium iron garnet (YIG) with various amounts of Fe^sub 2^O3 excess, as a tunable dielectric resonator antenna. The exploration of YIG's antenna microwave properties is a key to determine stability of the antenna radiation pattern and frequency shifting. YIG with various amounts of excess Fe^sub 2^O3 is prepared through a mixed oxide powder technique. Through X-ray diffraction analysis, it was found that addition of 5 wt% excess Fe^sub 2^O3 to YIG stoichiometric formulation has depleted YIP phases in YIG ceramics. However, increasing amount of excess Fe^sub 2^O3 in excess of 15 wt% led to increase in the Fe^sub 2^O3 residue in YIG ceramics. The grains observed using high resolution electron microscopy displayed a well-packed structure. The size of the grains became bigger when the percentage of Fe^sub 2^O3 increased to 20 % but accompanied with significant changes in electrical properties. This change has led to a frequency shift from 14.14 to 17.32 GHz, which cover applications within the Ku-band (12.00-18.00 GHz) together with radiation stability. These results imply that inclusion of excess Fe^sub 2^O3 can be used for tunable DRA.[PUBLICATION ABSTRACT]