Fabrication and characteristics of embedded passive substrate for application of RF modules

Abstract

Ultra miniaturized and low-profile mobile products are driving the need for embedded passive component integration technologies using a novel manufacturing-compatible organic substrate and interconnect technologies. Hence it is required a good performance and quality of embedded passive substrate that passive devices are embedded inside the substrate. It is currently one of the strongest candidates which can be used in order to meet the customer requirements in terms of size, performance, low-power design, high-frequency bandwidth, reliability and cost. This paper presents fabrication and electrical characteristics of embedded passive substrate that is embedded chip bead inductor and chip capacitor inside substrate for application of RF modules. We fabricated embedded passive substrate using embedding process that consists of lamination process, laser drilling at the electrode Cu pads of passive components, electroless Cu plating formation process such as photolithography, electrolytic Cu plating, and etching. We evaluated impedance and capacitance characteristics of the fabricated embedded passive substrate. For the case of embedding passive substrate with series and parallel circuits, we looked at how to test embedded passive substrate for knowing the accurate value of embedded passive components each other.