Conductor and Dielectric Property Extraction Using Microstrip Tee Resonators

Abstract

The growth and resultant competitive nature of the wireless industry has prompted the need for high frequency electronics to be provided at a low cost. An efficient method of component characterization is necessary to ensure that circuit designs meet the specifications for desired performance in as few design iterations as possible. The use of board “real estate” is also a consideration in the choice of a test structure to be used for component characterization. The open-ended quarter wave tee resonator in a microstrip configuration is such a test structure. This thesis describes a method using tee resonator measurements to extract line attenuation and further to extract dielectric relative permittivity and loss tangent if the characteristics of the conductor are assumed. Furthermore, a novel approach is presented where a pair of microstrip tee resonators are employed, each with a different impedance resonating element, and the behavior of the resonances is used to extract conductor sheet resistance as well as the dielectric properties. The method is demonstrated for screen-printed silver epoxy lines on an alumina substrate. This methodology is further examined by way of method of moments modeling. This modeling is used to validate the procedure that was developed for use on physical test boards.