Enhanced SiGe heterojunction bipolar transistors with 160 GHz-f/sub max/

Double-mesa type SiGe heterojunction bipolar transistors (HBTs) have been improved by increasing the base Gummel number and by using a thin, highly doped launcher layer between the base and the collector. In addition, the contact resistance of the base contact has been reduced. Hence, it was possible to obtain a record maximum frequency of oscillation up to 160 GHz for a 2-emitter finger HBT in common emitter configuration.

[1]  H. Schumacher,et al.  Low-noise performance of SiGe heterojunction bipolar transistors , 1994, Proceedings of 1994 IEEE Microwave and Millimeter-Wave Monolithic Circuits Symposium.

[2]  A. Schuppen,et al.  SiGe-HBTs with high fT at moderate current densities , 1994 .

[3]  U. Erben,et al.  MBE-grown Si/SiGe HBTs with high beta , f/sub T/, and f/sub max/ , 1992, IEEE Electron Device Letters.

[4]  J.M.C. Stork,et al.  Vertical profile optimization of very high frequency epitaxial Si- and SiGe-base bipolar transistors , 1993, Proceedings of IEEE International Electron Devices Meeting.

[5]  U. Konig,et al.  Multi emitter finger SiGe-HBTs with f/sub max/ up to 120 GHz , 1994, Proceedings of 1994 IEEE International Electron Devices Meeting.