Microwave Dielectric Properties of Doped BaTi <sub>4</sub> O <sub>9</sub>

Subodh G. Mhaisalkar, Dennis W. Readey, Sheikh A. Akbar

Journal of the American Ceramic Society · 1991 · 62 citations · 13 references

Concepts

Abstract

Polycrystalline BaTi 4 O 9 doped with Mn, Sn, Zr, Ca, Sr, and Pb was prepared from carbonates and oxides. Single‐phase ceramics with densities exceeding 97% of theoretical were made with up to 3 mol% Mn; 6 mol% Sn, Zr, and Ca; and 8 mol% Sr and Pb. Dielectric constant, k , quality factor, Q , and temperature coefficient of frequency, τ f , of ∼37, 5675, and 15 ppm/°C, respectively, were determined at 4 GHz for undoped BaTi 4 O 9 . Doping did not significantly affect k and τ f . However, doping with Mn, Sn, and Pb lowered Q , whereas doping with Zr, Ca, and Sr increased Q by up to 2000. Additions of 0.5 mol% MnO 2 as a second phase improved Q from 3675 to 7600.

References

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