2nd- and 4th-Order planar dual-mode ring filters at 140 GHz in a 130nm BiCMOS technology

Integrated planar filters at 140 GHz are hereby presented. 2
^nd
-order dual-mode ring-based filters are studied with and without MIM capacitive loads which allow a footprint reduction by 2.7. Both filters exhibit similar electric response with a 3-dB relative fractional bandwidth (FBW3dB) of 12 % and 4 dB of insertion loss. Two 4
^th
-order filters are formed by cascading two identic cells (with or without the MIM). They present a narrow FBW3dB of 9.5 % with insertion loss of approximately 10 dB. In this case, the capacitive loading leads to a 1.9 area reduction factor.