Materials and Technology for Microwave Integrated Circuits

Abstract

Advances over the past two decades in the planar techniques and technology and also in the miniature microwave solid state devices compatible with this technology have led to the realization of compact microwave integrated circuits (MICs). These circuits are built on planar transmission lines such as the stripline, microstrip line, suspended stripline, suspended microstrip, inverted microstrip, slot line, coplanar waveguide and coplanar strips. The basic geometries of these lines are shown in Fig. 1. For MICs, these planar transmission lines are formed on substrates made of low loss dielectrics, ferrimagnetics and semiconductors. A typical MIC consists of one or more of the following parts: (a) distributed elements (b) lumped elements in planar/discrete form, (c) semiconductor devices and (d) special elements such as dielectric resonators and ferrite discs. Two different technologies; viz. hybrid and monolithic are well accepted for the fabrication of MICs.