Title :
Analytical modeling of base transit time for a Si1−yGey heterojunction bipolar transistor
Author :
Arafat, Yeasir ; Khan, Md Ziaur Rahman ; Hassan, M. M Shahidul
Author_Institution :
Dept. of EEE, Bangladesh Univ. of Eng. & Technol. (BUET), Dhaka, Bangladesh
Abstract :
An analytical model for base transit time of an exponentially doped base npn Si1-yGey HBT has been developed. The model is valid in all levels of injection before the onset of Kirk effect. In this analysis, bandgap-narrowing effect, high-injection effect, carrier velocity saturation at the base edge of the base collector junction and doping dependent mobility are incorporated. It is found that base transit time depends on the Ge profiles in the base. The increase of Ge content for the same profile results in a decrease of transit time. Results of this work are compared with results available in literature.
Keywords :
heterojunction bipolar transistors; silicon compounds; Kirk effect; Si1-yGey; bandgap-narrowing effect; base collector junction; base transit time; carrier velocity saturation; doping dependent mobility; heterojunction bipolar transistor; high-injection effect; Analytical models; Current density; Doping; Electron mobility; Equations; Germanium silicon alloys; Heterojunction bipolar transistors; III-V semiconductor materials; Semiconductor process modeling; Silicon germanium; Base transit time; HBT; SiGe; high injection;
Conference_Titel :
Electron Devices and Solid-State Circuits, 2009. EDSSC 2009. IEEE International Conference of
Conference_Location :
Xi´an
Print_ISBN :
978-1-4244-4297-3
Electronic_ISBN :
978-1-4244-4298-0
DOI :
10.1109/EDSSC.2009.5394245
