Dc And Low-frequency-noise Characterization Of Epitaxially Grown Raised-emitter Sige Hbts

摘要

DC and low-frequency-noise characteristics of SiGe HBTs with a raised-emitter structure, fabricated by epitaxial growth of phosphorous-doped Si layers, were investigated. Experimental results indicate unexpected emitter-size dependencies of both base current and low-frequency noise, because mono-poly interfacial native oxides close to the intrinsic emitter-base junction are localized at the emitter periphery. The raised mono-Si emitter SiGe HBT with a scaled emitter exhibits low-frequency noise that is about ten times smaller than a conventional poly-Si emitter SiGe HBT.