Abstract
Ca5A2Ti1−x Hf x O12 (A = Nb, Ta) ceramics have been prepared as single-phase materials by conventional solid-state ceramic route. Their structure and microstructure were studied by X-ray diffraction and scanning electron microscopic methods and dielectric properties were characterised in the 4–6 GHz microwave frequency range. We observed an increase in cell volume and theoretical density with compositional variations. In Ca5Nb2Ti1−x Hf x O12 ceramics the dielectric constant varied from 48 to 22 and quality factor from 26000 to 16000 GHz whereas in Ca5Ta2Ti1−x Hf x O12 the variation in dielectric constant was from 38 to 17 and quality factor from 33000 to 18000 GHz with increase in x. In both the ceramic systems the temperature coefficient of resonant frequency shifted from positive to negative values with Hf 4+ substitution for Ti4+.
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References
D. Kajfez and P. Guillon, Dielectric Resonators (Artech House, Massachusetts, 1986).
L.A. Trinogga, G. Kaizhon, and J.C. Hunter, Practica Microstrip Circuit Design (Ellis, Horword, 1991).
G.L. Roberts, R.J. Cava, W.F. Peck, and J.J. Krajewski, J. Mater. Res., 12, 526 (1997).
A.I. Kingon, J.P. Maria, and S.K. Streiffer, Nature, 406, 1032 (2000).
M.T. Sebastian and A-K Axelsson, N Mc N Alford, Internet Data, URL: http://www.lsbu.ac.uk/dielectric-materials
M.R. Varma, R. Reghunandan, and M.T. Sebastian, Jpn. J. Appl. Phys., 44, 298 (2005).
K.P. Surendran, P. Mohanan, and M.T. Sebastian, J. Sol. State Chem., 177, 4031 (2004).
H. Ohsato, A. Atsushi, Y.T. Takagi, S. Nishigaki, and T. Okuda, Jpn. J. Appl. Phys., 39, 6608 (2000).
M.T. Sebastian, N. Santha, P.V. Bijumon, A. Axelsson, and NMcN. Alford, J. Eur. Ceram. Soc., 24, 2583 (2004).
R.J. Cava, J.J. Krajewski, and R.S. Roth, Mater. Res. Bull., 34, 355 (1999).
L.A. Bendersky, J.J. Krajewski, and R.J. Cava, J. Eur. Ceram. Soc., 21, 2653 (2001).
L.A. Bendersky, I. Levin, R.S. Roth, and A.J. Shapiro, J. Solid State Chem., 160, 257 (2001).
P.V. Bijumon, P. Mohanan, and M.T. Sebastian, Jpn. J. Appl. Phys., 41, 3384 (2002).
P.V. Bijumon, P. Mohanan, and M.T. Sebastian, Mat. Lett., 57, 1380 (2003).
P.V. Bijumon and M.T. Sebastian, J. Mater. Res., 19, 2922 (2004).
P.V. Bijumon, A. Dias, R.L. Moreira, P. Mohanan, and M.T. Sebastian, J. Appl. Phys., 95 (2005).
P.V. Bijumon and M.T. Sebastian, J. Am. Ceram. Soc., (communicated).
P.V. Bijumon and M.T. Sebastian, J. Amer Cer Soc., 88, 3433(2005).
P.V.Bijumon, Sreedevi. K. Menon, P. Mohanan, and M.T. Sebastian, Microwave Opt. Tech. Lett., 35, 327 (2002).
P.V. Bijumon, S.K. Menon, M.N. Suma, M.T. Sebastian, and P. Mohanan, Electron. Lett., 41 (2005).
S. Mridula, Sreedevi K. Menon, P. Mohanan, P.V. Bijumon, and M.T. Sebastian, Microwave Opt. Technol. Lett., 40, 316 (2004).
M.N. Suma, P.V. Bijumon, M.T. Sebastian, and P. Mohanan (unpublished results).
J. Krupka, K. Derzakowski, B. Riddle, and J.B. Jarvis, Meas. Sci. Technol., 9, 1751 (1998).
B.W. Hakki and P.D. Coleman, IRE Trans. Microwave TheoryTech., MTT-8, 402 (1960).
W.E. Courtney, IEEE Trans. Microwave Theory Tech., MTT-18, 476 (1970).
H.M. Shirey, Low temperature synthesis of the microwave dielectric material Barium Magnesium Tantalate (BMT), (M. S. Thesis, University of Pittsburg 2002).
R.D. Shannon, Acta Cryst., A32, 751 (1976).
R.S. Roth, J. Research of the National Bureau of Standards, 58, 75 (1957).
S.J. Penn, N.McN. Alford, A. Templeton, X. Wang, M. Xu, M. Reece, and K. Schrapel, J. Am. Ceram. Soc., 80, 1885 (1997).
R.D. Shannon, J. Appl. Phys., 73, 348 (1993).
S. Hirano, T. Hayashi, and A. Hattori, J. Am. Ceram. Soc., 74, 1320 (1991)
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Bijumon, P.V., Sebastian, M.T. Microwave dielectric properties of temperature stable Ca5A2Ti1−x Hf x O12 (A = Nb, Ta) ceramics. J Electroceram 16, 239–245 (2006). https://doi.org/10.1007/s10832-006-8279-8
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DOI: https://doi.org/10.1007/s10832-006-8279-8