Influence of collector region design on SiGe power HBT linearity characteristics

The influence of collector region design (used to realize different breakdown voltages) on the linearity characteristics of SiGe power HBTs is investigated experimentally via the measurements of third order intermodulation distortion (IMD3). It is shown that collector doping concentration has significant influence on devices' characteristics. SiGe power HBTs with higher collector doping concentration exhibit both better linearity characteristic and better RF power performance than the low collector doping concentration HBTs.