Multi-layer FCCSP organic packaging for D-band millimeter wave applications

A multi-layer, organic, low-loss flip-chip chip-scale package (FCCSP) for sub-THz applications has been developed and validated with on-package passive structures operating in the frequency band of 100 GHz to 140 GHz. The designed package co-integrates an electromagnetic wave launcher, a dual band multiplexer and a wideband through package transition. The wave launcher includes two rectangular patches separated by dielectric layers and supports a radiation bandwidth of 40 GHz. It has a return loss better than 10 dB in the designed bandwidth and an insertion loss between 1 to 1.5 dB. The on-package multiplexer (diplexer) combines two bandpass hairpin resonator filters. The two filters are designed to have a minimum bandwidth of 12 GHz each. The designed diplexer also has a return loss better than 10 dB and an insertion loss between 4 to 5 dB. Our work is a leading demonstrator for FCCSP packaging in the 100 to 140 GHz frequency range. We show that with the current fabrication processes, organic packaging is a valuable low-loss solution for sub-THz millimeter wave applications.