A 94 GHz Antenna On-Silicon Interposer With Parasitic Elements for Bandwidth Improvement

Abstract

This paper presents a microstrip antenna operating at 94 GHz. This design integrates a primary patch radiator surrounded by an array of small parasitic square patches to improve the bandwidth (BW). The low profile of this design allows the integration and fabrication of antenna arrays with an inter-element isolation of less than -15 dB. The design is fabricated on a high resistivity silicon (HR-Si) substrate with a thickness of 130 mu m and the interconnection between the probe Ground-Signal-Ground (GSG) pads and ground plane is performed by two Through-Silicon-Vias (TSVs). The impedance BW enhancement is verified by the -10 dB experimental return loss from 90 GHz to 100 GHz. On the other hand, simulation results of the radiation pattern show a gain higher than 5.8 dBi from 88 GHz to 98 GHz. Finally, the inter-element coupling is less than -19.5 dB for antennas disposed on E and H-plane alignment.