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IEEE Transactions on Microwave Theory and Techniques
Volume 48 Number 5, May 2000

A Low-Impedance Coplanar Waveguide Using an SrTiO₃ Thin Film for GaAs Power MMIC's

Page 872.

Abstract:

A novel structure for coplanar-waveguide transmission lines with low impedance and low loss is demonstrated in this paper. The new structure simply has a high dielectric SrTiO₃ thin film underneath the coplanar conductors. Due to the high dielectric constant of SrTiO₃, the coplanar line exhibited characteristic impedance as low as 18 with a slot width of 5 µm and the center conductor width of 50 µm, while a conventional coplanar line on GaAs showed only 30 with the same configuration. The newly developed coplanar structure is easily applicable for present GaAs monolithic-microwave integrated-circuit (MMIC) technology,especially for power MMIC's and low-impedance devices.

References

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