A compact 3D silicon interposer package with integrated antenna for 60GHz wireless applications

A 6.5×6.5 mm² compact silicon interposer encompassing 2 Tx/Rx antenna, one RF chips, TSV via-last has been designed and fabricated for 60 GHz fast data transmission applications. First characterizations are described in this paper with a focus on reliability, antenna performances and Through-Silicon-Vias (TSV) characterization. It is first shown that more than 500 thermal cycles can be achieved with a double polymer layer passivation on the Si interposer backside and polymer core solder balls. Secondly, the folded dipole antenna with a reflector on PCB have shown suitable properties (5 dBi in gain, -10 dB cross polarization) for mmw applications, which make silicon a competitive substrate for antenna integration. Finally, single TSV Ground-Signal-Ground transition has been characterized and successfully extracted up to 67GHz, with loss below 0.6 dB at 60GHz.