SiGe:C Heterojunction Bipolar Transistors: From Materials Research to Chip Fabrication.

Incorporation of substitutional carbon (≈ 1020cm−3) into the SiGe region of a heteroj unction bipolar transistor (HBT) strongly reduces boron diffusion during device processing. We describe the physical mechanism behind the suppression of B diffusion in C-rich Si and SiGe, and explain how the increased thermal stability of doping profiles in SiGe:C HBTs can be used to improve device performance. Manufacturability of SiGe:C HBTs with transit frequencies of 100 GHz and maximum oscillation frequencies of 130 GHz is demonstrated in a BiCMOS technology capable of fabricating integrated circuits for radio frequencies with high yield. [ABSTRACT FROM AUTHOR]