D-band Heterogeneous Integrated Antenna

This paper introduces a novel class of heterogeneous integrated antennas (HIA) designed for sub-terahertz applications. The proposed HIA combines the strengths of both on-chip and in-package antennas, offering not only high gain and radiation efficiency but also eliminating the need for additional bond wires or solder bumps. Two types of HIAs, namely downward-radiated HIA and upward-radiated HIA, are developed, featuring on-chip excitation and off-chip packaging designs. The on-chip excitation seamlessly interfaces with monolithic microwave integrated circuits (MMIC), while the off-chip packaging is flexibly tailored to enhance radiation efficiency. Two dual-polarized demonstrations are constructed by on-chip 40-nm CMOS technology and off-chip microelectromechanical system (MEMS) packaging processes, achieving a maximum gain of 4.9 dBi, maximum efficiency of 52.6%, and cross-polarization discrimination (XPD) better than 45 dB. Additionally, the on-chip footprint is reduced by approximately 60% compared to traditional on-chip antenna.