SiC Growth and Its Application to High-Speed Si-HBTs

This paper discusses the limitations of a conventional poly-Si emitter for sub 0.5¿m bipolar transistors and presents a breakthrough using a heterojunction at the emitter-base junction with an SiCx widegap emitter. Both SiCx widegap emitter HBTs and poly-Si emitter transistors with comparable device structures are examined. Low base resistance was achieved using a 1×10¹⁹/cm³ base dopant concentration, while retaining an acceptable current gain and suppressing forward-bias tunneling current using the SiCx emitter. A very thin , highly doped base was combined with the SiCx emitter to demonstrate high-speed capability.