SiGe HBT Technology Based on a 0.13- $\mu{\rm m}$ Process Featuring an ${f}_{\rm MAX}$ of 325 GHz

A self-aligned SiGe HBT technology achieving a cutoff frequency $({f}_{\rm T})$ of 253 GHz was developed using a selective SiGe epitaxial growth process. Germanium concentration in an i-SiGe layer just under a ${\rm p}^{+}$ intrinsic base region was raised to 27.4% to improve ${f}_{\rm T}$ , and boron concentration in the intrinsic base region reached $2.4\times 10^{20}~{\rm cm}^{-3}$ as a deposition to maintain a breakdown voltage of 1.5 V. A 0.13- $\mu{\rm m}$ SiGe BiCMOS technology geometrically advanced from an earlier 0.18- $\mu{\rm m}$ version shrinks the emitter width from 0.2 to 0.12 $\mu{\rm m}$ to reduce collector-base capacitance and base resistance. It achieves a maximum oscillation frequency $({f}_{\rm MAX})$ of 325 GHz. This technology can be applied to optical and mm wave communication systems.