Pushing SiGe Beyond 350GHz

IBM claims the worlds fastest silicon-based transistor operating at speeds of 350GHz. The bipolar transistor uses a modified design and IBMs fifth generation silicon germanium (SiGe) technology. IBMs new transistor performs nearly 300% faster than todays production devices, and is 65% faster than previously reported silicon transistors. IBM anticipates the new transistor will lead to communications chips with speeds of more than 150GHz in about two years. IBM used a novel vertical profile scaling technique to reduce the height of the bipolar transistor, to shorten the electrical flow path and improve performance. The SiGe chips are built on existing manufacturing lines at IBMs facility in Burlington, Vermont. Details of the technology will be presented in an IBM paper at the International Electron Devices Meeting (IEDM) in San Francisco, Dececember 9-11, 2002 ("SiGe HBTs with Cut-off Frequency Near 300GHz"). The improved 350GHz speed was achieved after the paper was submitted. German high performance BiCMOS foundry start-up Communicant Semiconductor Technologies and its technology partner Innovations for High Performance microelectronics (IHP) will also be reporting at IEDM on high-speed SiGe:C BiCMOS (Bulletin 450, September 16, 2002). Communicant's heterojunction bipolar transistor (HBT) module offers an fT of 200GHz and an fmax of 170GHz. IBMs previous SiGe transistor performance announcement (Bulletin 421, February 25, 2002) was for speeds of more than 110GHz.