A Low-Loss Balun-Embedded Interconnect for THz Heterogeneous System Integration

An interconnect for THz heterogeneous integration is proposed in this work. Two transmission lines deployed on a 40-nm CMOS chip and an IPD carrier, respectively, are coupled together to form a Marchand balun during a flip-chip packaging process. By doing this, the proposed interconnect can provide packaging and balun functions simultaneously. Two interconnects using the proposed idea are demonstrated with measured and simulated insertion loss of 0.9 and 1.4 dB at 169 and 340 GHz, respectively.