Title :
Double-diffused graded SiGe-base bipolar transistors
Author :
Vook, Dietrich ; Kamins, Theodore I. ; Burton, Gregory ; Voorde, P.J. ; Wang, H.-H. ; Coen, R. ; Lin, J. ; Pettengill, D.F. ; Yu, P.-K. ; Rosner, S.J. ; Turner, E. ; Laderman, S.S. ; Fu, Horng-Sen ; Wang, Albert S.
Author_Institution :
Hewlett-Packard Co., Palo Alto, CA, USA
fDate :
6/1/1994 12:00:00 AM
Abstract :
Self-aligned SiGe/Si bipolar transistors have been fabricated using a single-polysilicon, double-diffused process with the base in a graded SiGe layer to improve base transit time. To remain compatible with homojunction bipolar technology, undoped SiGe base and Si emitter layers were deposited by selective epitaxy at temperatures of 700-750°C in a commercial epitaxial reactor. Maximum cutoff frequencies of 40 and 50 GHz were observed for devices with collector-emitter breakdown voltages (BVCEO) of 4.2 and 3.0 V, respectively. Preliminary results indicate that the addition of Ge to the base of these transistors did not degrade the long-term device reliability
Keywords :
Ge-Si alloys; bipolar transistors; doping profiles; elemental semiconductors; ion implantation; semiconductor growth; semiconductor materials; silicon; solid-state microwave devices; vapour phase epitaxial growth; 3 V; 4.2 V; 40 GHz; 50 GHz; 700 to 750 C; SiGe-Si; base transit time; collector-emitter breakdown voltages; graded SiGe layer base; long-term device reliability; selective epitaxy; self-aligned bipolar transistors; single-polysilicon double-diffused process; undoped Si emitter layer growth; undoped SiGe base layer growth; Bipolar transistors; Boron; Current density; Electron emission; Epitaxial growth; Germanium silicon alloys; Inductors; P-n junctions; Silicon germanium; Temperature;
Journal_Title :
Electron Devices, IEEE Transactions on
