Wideband mixed lumped-distributed-element 90° and 180° power splitters on silicon substrate for millimeter-wave applications

This paper presents two millimeter-wave lumped-distributed 90deg and 180deg power splitters fabricated in the back-end-of-the-line (BEOL) of a 0.18 mum SiGe BiCMOS technology. The 180deg and 90deg power splitters based on mixed lumped-distributed-element three-port Wilkinson power divider with phase shifters at the outputs are shown to achieve an amplitude balance of better than 0.05 dB and 0.21 dB, respectively, at 77 GHz. The return losses for both power splitters are better than 12 dB from 70 GHz to 80 GHz. The effective areas of the 180deg and 90deg splitters are 240 times 440 mum² and 220 times 400 mum², respectively.