Novel Collector Structure Enabling Low-Cost Millimeter-Wave SiGe:C BiCMOS Technology

A millimeter-wave selective-epi, SiGe:C HBT is described, utilizing a novel, low-cost collector construction. A cutoff frequency (f T ) of 200 GHz and a maximum oscillation frequency (f MAX ) of 300 GHz is achieved using a self-aligned selective-epi base structure. For a SiGe:C HBT, this is the highest known f MAX obtained without the use of buried layer or deep trench isolation.