Design of high-efficiency millimeter-wave microstrip antennas for silicon RFIC applications

This paper presents the design information for a W-band high-efficiency, electromagnetically-coupled on-chip silicon microstrip antenna. The antenna is composed of a quartz substrate placed on top of a commercial low-resistivity SiGe BiCMOS silicon chip. Design criteria for the microstrip antenna taking into account the dielectric and metal-density rules for the different layers of the BiCMOS silicon chip are presented. The antenna results in a measured S11 bandwidth of 91.5-98.5 GHz, a measured gain of 0.7-3.9 dB and a radiation efficiency of 48 +/-8% at 91-100 GHz. The design is scalable to N×M elements and to wafer-scale arrays. The application areas are in wafer-scale phased arrays, on-chip low-power sensors, communication systems, and mm-wave collision avoidance radars. To our knowledge, this is the highest gain and efficiency silicon on-chip antenna at mm-wave frequencies.