An advanced BiCMOS process utilizing ultra-thin silicon epitaxy over arsenic buried layers

Abstract
A description is given of SABRe (Submicron Advanced BiCMOS Research), a 0.8- mu m CMOS-based BiCMOS process that utilizes ultrathin (0.8- mu m) undoped epitaxial layers grown on n/sup +/ (arsenic) and p/sup +/ (boron) buried layers. The use of this undoped epitaxial layers enables the independent tailoring of the substrate doping profiles in the MOS and bipolar regions through surface implants alone. Surface channel NMOS and PMOS transistors using n/sup +/ and p/sup +/ doped polysilicon gates with 0.5 mu m effective channel length were achieved along with npn transistors with 11.5-GHz cutoff frequency. The process also features self-aligned cobalt silicide for the gate/emitter and source-drain.<>