Uniaxial and Biaxial Substrate Effects on Uniform Finlines and Finline Step Discontinuities

Abstract

Substrate materials exhibit inherent anisotropy which affects the dispersive characteristics of uniform finlines and finline discontinuities with increasing frequency. An accurate model is presented which accounts for uniaxial or biaxial anisotropy. The error involved in neglecting such substrate properties is discussed. In addition, the effect of anisotropy on the step discontinuity is analyzed and a comparison of the accuracy of the transverse resonance method and the mode matching technique is provided.