Silicon:germanium-based mixed-signal technology for optimization of wired and wireless telecommunications

The need to serve the explosion in data bandwidth demand for fixed and mobile applications has driven transistor performance requirements beyond the reach of conventional silicon devices. Scaling limits of silicon-based bipolar transistors have been encountered, confining further performance gains by traditional means, but cost considerations favor the continued use of silicon-derived technology solutions. Silicon:germanium (Si:Ge) heterojunction bipolar transistors (HBTs) and subsequent generations of highly integrated SiGe BiCMOS processes stem from long-term efforts initiated at IBM to develop such a silicon-derived technology. This paper reviews the application-driven origins of this SiGe technology, how it has evolved, and how limits to conventional silicon bipolar scaling have enhanced its adoption in the semiconductor industry. Examples of the entry of this technology into commercialapplications in the wired and wireless marketplace are discussed.