This monograph reports a research carried out to design monolithic
microwave integrated circuit (MMIC) low pass filters using circuit and
electromagnetic simulations. The filters were designed to be constructed
on both Si and GaAs semiconductor wafers. The principal objectives were
to reduce both circuit size and spurious content. Three types of designs
are proposed here. The first is a Butterworth filter made of
commensurate stubs, while the second filter is of the m-derived type.
Both filters are realized using a single gold layer on the semiconductor
substrate. The third filter uses a novel metal/polyimide/metal
multilayer structure consisting of buried coplanar waveguide and
polyimide overlay. Owing to the unique multilayer architecture, the
filter operates well without spurious in the passband and stopband. The
combination of several different materials in the structure also reduces
the size. The proposed filter has stopband insertion and return losses
of 20 dB and 25 dB respectively. A theoretical model to explain the new
structure and design methodology are discussed in detail.