Ferrimagnetic Substrates for Microwave Integrated Circuits

A number of microwave investigators [references 1, 2, 3] have succeeded in demonstrating the feasibility of constructing useful microwave components on ferrimagnetic substrates using printed circuit techniques. This whitepaper describes the methods for the ceramic fabrication of microwave ferrite substrates of a 4 square-inch area. The economic production of Microwave Integrated Circuits(MICs) on ferrimagnetic substrates requires that as-fired geometric tolerances be held within values that are compatible with circuit design requirements. These parts exhibit intrinsic technical properties and as-fired mechanical tolerances that are suitable for the construction of microstrip ferrimagnetic devices.

The elimination of machining to obtain usable mechanical tolerances provides for a cost reduction of ferrite parts. The white paper also discusses methods of improving the surface finish, when required.