No CrossRef data available.
Article contents
Towards the Integration of Barium Ferrite Sputtered Films for Coplanar Isolators and Circulators in the Millimeter Wave Range
Published online by Cambridge University Press: 26 February 2011
Abstract
Signal processing in communication, instrumentation and radar detection requires low cost microwave and millimeter wave devices. The integration of millimeter wave passive components like isolators and circulators is thus a major issue. In these components, the nonreciprocal nature of wave propagation in ferrites plays an essential role. Hexagonal ferrites, such as barium ferrite (BaFe12O19 or BaM), which has a large resistivity and high permeability at high frequency, are of great interest for such applications. The present work deals with the characterization of barium hexaferrite sputtered films and with the device integration for the development of coplanar isolators and circulators working at frequencies around 40 GHz.
The BaM films (in the thickness range of 10μm) were deposited on alumina substrate by RF magnetron sputtering at room temperature and were then crystallized using a 800°C thermal annealing. Structural properties were evaluated by X-ray diffraction and the magnetostatic properties of the film were determined using a Vibrating Sample Magnetometer (VSM) leading to assess a range of deposition conditions appropriate for device integration.
Both coplanar isolators and circulators were implemented using standard lift-off technique. Coplanar circulators were designed by analytical calculation and 3D electromagnetic simulation (HFSS) supposing a saturated material and no losses. The microwave range characterization was performed using a network analyzer and a probing system with a prior OSTL calibration. The coplanar isolators were characterized both at the remanence and under a polarizing field. At the remanence, the gyroresonance occurred at 50 GHz and the nonreciprocal effect - difference between the transmission coefficient in the forward direction and in the reverse direction - was evaluated. When applying a polarizing field, the tunability of the isolator was verified experimentally. Finally first measurements on integrated coplanar circulators are currently under progress.
- Type
- Research Article
- Information
- Copyright
- Copyright © Materials Research Society 2007
References
1.
Bosma, H., IEEE Trans. Microwave Theory & Tech. MTT-
12, 61 (1964).10.1109/TMTT.1964.1125753Google Scholar
2.
Helszajn, J., Nonreciprocal microwave junctions and circulators, John Wiley & Sons, 1975.Google Scholar
3.
Saib, A., Darques, M., Piraux, L., Vanhoenacker-Janvier, D., Huynen, I., Proc. Eur. Microwave Ass.
1, 67 (2005).Google Scholar
4.
Berre, M. Le, Capraro, S., Chatelon, J. P., Joisten, H., Rouiller, T., Bayard, B., Barbier, D., Rousseau, J. J., in Materials, Integration and packaging Issues for High-Frequency Devices edited by Muralt, P., Cho, Y.S., Klee, M., Maria, J.P., Randall, C.A., Hoffman, C., (Mater. Res. Soc. Symp. Proc 783, Pittsburgh, PA, 2004) pp.151–156.Google Scholar
5.
Pankhurst, Q. A., J. Phys. Condens. Matter.
3, 1323 (1991).10.1088/0953-8984/3/10/010Google Scholar
6.
de Lacheisserie, E. du Trémolet, «Magnétisme », Presses Universitaires de Grenoble, 1999, 496 p., volume 1, Chapter 3.Google Scholar
7.
Liu, W.F., Suzuki, S., Li, D.S., Machida, K., J. Magn. Magn. Mat.
302, 201 (2006).10.1016/j.jmmm.2005.08.019Google Scholar
8.
Bayard, B., Vincent, D., Simovski, C.R., Noyel, G., IEEE Trans. Microwave Theory Tech.
51, 1809 (2003).10.1109/TMTT.2003.814312Google Scholar
9.
Berre, M. Le, Capraro, S., Chatelon, J. P., Rouiller, T., Bayard, B., Barbier, D., Rousseau, J. J., in Materials, Integration and packaging Issues for High-Frequency Devices II edited by Cho, Y.S., Schiffler, D., Randall, C.A., Tilmans, H.A.C., Tsurumi, T., (Mater. Res. Soc. Symp. Proc. 833, Pittsburgh, PA, 2005) pp.165–170.Google Scholar