A 2 pole micromachined bandpass filter at 150 GHz

The conception of a two pole micromachined bandpass filter at 150 GHz is presented. By exploring a coplanar to microstrip transition, from a silicon substrate to air with a 3D electromagnetic computation, a ground layer between the membrane and the substrate has been used to avoid substrate modes in the filter accesses. An adaptation higher than 30 dB has been obtained in the bandpass and the computed unloaded quality factor is 560. The bandwidth is 6% and the insertion losses of the filter are lower than 1 dB.