A Wideband W-Band Slotted Over-Mode Cavity Array with Dumbbell-Shaped Holey-EBG Units Based on Metallic Silicon-Based Process

The W-band slotted over-mode cavity array with a novel dumbbell-shaped (DS) holey electromagnetic band gap (holey-EBG) unit is presented, which is fabricated by the metallic silicon-based (Si-based) process. The proposed DS holey EBG structures can effectively suppress the electromagnetic (EM) leakage between multilayer metallic Si-based plates. Its mechanism is explored and investigated in detail. Moreover, a wideband excitation of high-order mode is realized in this array antenna. The 8×8 antenna array with and without DS holey EBG structures are designed. The realized gains of the designed array with holey EBG units improved by 1–2 dB compared to non-EBG array, indicating that the proposed DS holey-EBG structure can well suppress the EM leakage within multilayer metallic waveguides. The -10 dB impedance bandwidth ranges from 90 to 109.5 GHz (19.5% of relative bandwidth).