We demonstrate a novel HBT-before-CMOS integration scheme to integrate SiGe:C HBTs with a 130 nm gate length CMOS frontend. This scheme entirely eliminates the impact of the HBT thermal steps on CMOS characteristics, opening the way for easy, modular integration of high-performance HBTs into highly scaled CMOS technologies. C doping of the SiGe layer prevents the degradation of HBT parameters by critical CMOS thermal steps. This is demonstrated for SiGe:C HBTs with f,J f , , values of 801 90 GHz fabricated in the HBT-before-CMOS scheme and in a benchmark HBTonly process.