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Microwave Dielectric Properties of LaScO3-TiO2 Materials

Published online by Cambridge University Press:  01 February 2011

Do-Kyun Kwon ,
Michael T. Lanagan  and
Thomas R. Shrout
Do-Kyun Kwon
Affiliation:
Materials Research Institute, The Pennsylvania State University, University Park, PA.16802, U.S.A
Michael T. Lanagan
Affiliation:
Materials Research Institute, The Pennsylvania State University, University Park, PA.16802, U.S.A
Thomas R. Shrout
Affiliation:
Materials Research Institute, The Pennsylvania State University, University Park, PA.16802, U.S.A
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Abstract

From fundamental ionic polarizability concepts, LaScO3 was projected as a candidate dielectric material for microwave application. The microwave dielectric properties of LaScO3 were obtained as the dielectric permittivity of 24, Q×f of 18,000 GHz, with a temperature coefficient of resonant frequency (TCF) of −69 ppm/°C. Solid solutions and polyphase assemblages were investigated in the LaScO3-TiO2 system as a function of TiO2 content, and correlated with the microwave dielectric properties. Orthorhombic perovskite LaScO3 transformed to tetragonal symmetry with Ti substitution on the B-site of LaScO3 owing to the ionic radius difference between Sc3+ and Ti4+. With this phase transition, the formation of A-site vacancies (VLa‴) resulted in the precipitation of a La deficient secondary phase. The substitution of Ti also affected the dielectric properties. The dielectric constant increased and TCF became less negative with increased TiO2 addition. However, the Q×f value decreased, due to the formation of the secondary phase. For the case of the 0.6LaScO3-0.4TiO2 composition, a dielectric K of 40, Q×f of 6,000 GHz and nearly zero TCF were obtained.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 783: Symposium B – Materials, Intergration, and Packaging Issues for High-Frequency Devices , 2003 , B5.14
Copyright
Copyright © Materials Research Society 2004

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References

REFERENCES

1. Harshe, G., Bhalla, A.S. and Cross, L.E., Mater. Lett. 18, 173 (1994).Google Scholar
2. Kucheiko, S., Kim, H.J., Yeo, D.H., and Jung, H.J., Jpn. J. Appl. Phys. 35, 668 (1996).Google Scholar
3. Cho, S.Y., Kim, I.T., and Hong, K.S., J. Mater. Res. 41 (1), 114 (1999).Google Scholar
4. Lim, D.G., Kim, B.H., Kim, T.G., and Jung, H.J., Mater. Res. Bull. 34 (10/11), 1577 (1999).Google Scholar
5. Cho, S.Y., Hong, K.S., and Ko, K.H., Mater. Res. Bull. 34 (4), 511 (1999).Google Scholar
6. Shannon, R.D., J. Appl. Phys. 73 (1), 1 (1993).Google Scholar
7. Hakki, B.W. and Coleman, P.D., IEEE Trans. Microwave Theory & Technol. MTT–8 (7), 402 (1960).Google Scholar
8. Fratello, V.J. and Brandle, C.D., J. Mater. Res. 9, 2554 (1994).Google Scholar
9. Wersing, W., Sol. Stat. & Mater. Sci. 1, 715 (1996).Google Scholar