Quasi-TEM Characteristic Impedance of Micromachined CMOS Coplanar Waveguides
Mehmet Ozgur, V. Milanovic, C. A. Zincke, Michael Gaitan, Mona E. Zaghloul
Micromachined coplanar waveguides fabricated in CMOS technology consist of glass-encapsulated finite-thickness metal conductor strips, fully suspended by selective etching of the silicon substrate. Determination of the quasi-TEM mode characteristic impedance requires knowledge of the quasi-static capcitance of the complete structure, and the quasi-static capacitance of the equivalent air-line structure. In this paper, analytical results are derived for such structures based on conformal mapping transformations and partial capacitance approach. The analytical results and proposed approximations are verified by a finite-difference computational approach and by measurement results on various sample structures. The results are useful for solving general capacitance problems for finite-thickness planar transmission lines with multi-layer dielectric.
IEEE Transactions on Microwave Theory and Techniques
, Milanovic, V.
, Zincke, C.
, Gaitan, M.
and Zaghloul, M.
Quasi-TEM Characteristic Impedance of Micromachined CMOS Coplanar Waveguides, IEEE Transactions on Microwave Theory and Techniques
(Accessed December 6, 2023)