Ultra-high-speed scaled-down self-aligned SEG SiGe HBTs

A self-aligned selective-epitaxial-growth (SEG) SiGe HBT with a funnel-shape emitter electrode, which is structurally optimized for an emitter being scaled-down towards 100 nm, was developed. This SiGe HBT has an ECL gate delay of 4.9 ps, and implemented in an ultra-high-speed static frequency divider, produces a maximum operating frequency of 81 GHz.