Millimeter-wave filter using novel micromachined substrate integrated waveguide structure with embedded silicon vias in BCB dilectrics

Abstract

This paper reports a millimeter-wave bandpass filter (BPF) based on a novel micromachined substrate integrated waveguide (SIW) structure with square complementary split-ring resonators (CSRRs). Four CSRRs are introduced to the SIW as an element providing passband characteristics below a cutoff frequency of the waveguide required for BPF. Unlike usual SIW-BPFs, the proposed BPF can be integrated with silicon-based circuits or RF MEMS devices by micromachining batch process due to its silicon process compatibility. In order to change the propagation mode from TEM to TE10, triangular slots are utilized as a CPW to waveguide transition. The fabricated BPF shows a high selectivity with a minimum insertion loss of 2.27 dB at 14 GHz and a 3-dB bandwidth of 9.3 %. These measured results are in good agreement with the simulation results.