30 GHz self-assembled highly-efficient on-chip monopole antennas

A novel monopole antenna made from an out-of-plane stressed cantilever beam is presented. The radiating element is isolated from a low-resistivity silicon substrate with a ground plane and thus high radiation efficiency of more than ∼50% can be achieved even with a CMOS-grade silicon substrate. The proposed antennas can be readily fabricated by a conventional IC fabrication process, which enables a high level of integration and low cost. Our experimental results of the monopole operating at 30 GHz agree well with our theoretical predictions.