Multilayer MMIC for stacked integrated circuits

In the flip-chip mounting of MMIC chips, an adequate separation between the flip chip and the mounting substrate must be maintained to prevent undesirable loading effects. In this paper, as an approach to solve this restriction, an electrically shielded MMIC is presented. This can be realized employing multilayer MMIC technology. An electrically shielded MMIC amplifier has been designed and fabricated, and satisfactory performance with excellent designability has been obtained. Furthermore, by using the electrically shielded MMICs, a novel high-density IC module construction providing excellent electrical and thermal functions, named "Stacked Integrated Circuits", is proposed.