Structures in Anisotropic Multilayered Media

Applying the concept of spectral domain representation, the moment method or the point-matching procedure and Green's function theory, a unified approach for the computation of the static capacitance of single, coupled and comb-like metallic structures in anisotropic multilayered media is presented. The media can be electrically shielded on one or both sides. The geometry of the parallel strips may be arbitrary and not all the strips need to be driven electrically, i.e. they may float. An overview of the relevant methods is followed by a discussion of an efficient approach with a wide range of applicabilty. I.Introduction Many problems of greatest practical interest demand an efficient solution procedure for the calculation of the capacitance for metallic strips, deposited on the surface or within a layered dielectric structure Ill. Because of the complexity of the associated boundary value problem and due to the fact that generally the layers are dielectrically anisotropic, direct numerical method are highly time-consuming. On the other hand approximate formulae, which are used by other authors have a restricted range of validity. We present a rigorous semi-numerical method of analysis covering a large class of problems. Although only a restricted number of problems is considered here, the method is quite general and can be extended to embrace a class of much more complicated problems. The method of analysis, a uniformly valid representation, is based on the concept of spectral domain representation and the method of moments, which are combined with an auxiliary quantity, the Green's function. First, closed-form formulae for the Green's function in the wavenumber domain have been derived for a variety of cases, which are of practical interest. Using the derived Green's function and the method of moments, the associated integral equation is replaced by a matrix equation, which can easily be solved by standard routines. Although the Green's function theory is by no means a new field, very recently it has found some important applications 121. The aim of this paper is to show that the advantages of the Green's function can be extended using the method of moments or a specialization of it, called point-matching or collocation method. Using the Fourier transform technique the boundary conditions are transformed into a set of algebraic equations. Therefrom a relation between the spec-