A simplified high-speed bipolar process with Ti salicide metallization: Implementation of in situ p-doped polysilicon emitter

A simplified double-polysilicon bipolar process utilizing only four photoli thography steps has been developed. The process features full self-alignmen t of emitter-base module and titanium self-aligned silicide metallization. The simplified process has been used as a test vehicle in implementation of an in situ phosphorus doped polysilicon technology. The base and collector currents demonstrated nearly ideal behavior in the Gummel plot resulting i n high common-emitter current gain around 200. High-frequency measurements revealed a peak cut-off frequency of 9 GHz measured directly on the silicid e. The results from the simplified process have been shown to be directly t ransferable to a full-scale bipolar technology.