Investigation of an embedded RF switch IC in printed-circuit-board

This paper presents the interconnection performance of the embedded integrated-circuit (IC) in printed-circuit-board (PCB) against wire-bonding method. Embedding IC into PCB substrate, micro-vias were adopted to interconnect the IC to the substrate. In order to consider the RF performance of the interconnection used for embedding IC into the PCB substrate, a double-pole-double-through (DPDT) switch IC was selected as an embedded RF IC. The insertion loss (IL) and the return loss (RL) of each switch were measured in order to compare the wire-bonded switch IC to the embedded switch IC. As a result, the wire-bonded switch IL is better than 0.7 dB and the RL is 16.2 dB at 5 GHz. The embedded switch IL is 0.6 dB and the RL is greater than 33.5 dB at 5 GHz. In addition to this, the embedded switch RL is better than 25 dB until 7 GHz. Thus the micro-via interconnection of the embedded switch in PCB substrate demonstrated better the RF performance than wire-bonding method in perspectives of the RL and the IL. This paper presents the advantages of the embedded IC in PCB by using micro-via.