S-parameter analysis of flip-chip transitions

Flip-chip interconnections are attractive for high density packaging of MMIC and optoelectronic modules. In this paper we investigate the electrical performance of flip-chip transitions between two coplanar waveguides in the presence of a short-circuited ground plane of either the CPW on the motherboard side or on the chip side. The method of analysis is based on the frequency-domain TLM approach which provides a rigorous field theoretical treatment of this type of discontinuity.