Planar Highly Efficient High-Gain 165-GHz On-Chip Antennas for Integrated Radar Sensors

This letter demonstrates different planar highly efficient on-chip antennas at 165 GHz with high gain utilizing a standard silicon-Germanium bipolar-complementary metal-oxide-semiconductor (Bi-CMOS) process with a localized backside etching (LBE) feature that allows cutting air trenches in the silicon. A dipole antenna, a folded dipole antenna with air trenches around the radiator, and a single-ended patch antenna with air trenches at the radiating edges are designed, fabricated, and characterized in the D-band (110–170 GHz). The geometry of each individual antenna and the LBE air trenches are optimized to meet both process reliability specifications and radiation performance simultaneously. Metal fillings effects on the radiation pattern and matching are also studied.