On the consistent modeling of band-gap narrowing for accurate device-level simulation of scaled SiGe HBTs

Author

Shi, Yun ; Niu, Guofu ; Cressler, John D. ; Harame, David L.

Author_Institution

Electr. & Comput. Eng. Dept., Auburn Univ., AL, USA

Volume

50

Issue

5

fYear

2003

fDate

5/1/2003 12:00:00 AM

Firstpage

1370

Lastpage

1377

Abstract

We investigate the modeling of heavy-doping induced band-gap narrowing (BGN) in scaled SiGe HBTs featuring high base doping. An inconsistency between simulation results obtained using either Boltzmann or Fermi-Dirac statistics is identified for two widely used commercial device simulators: MEDICI and DESSIS. A new approach to BGN modeling is introduced to correct this problem, and is successfully implemented in DESSIS, enabling consistency in the DC and RF characteristics simulated using either Boltzmann or Fermi-Dirac statistics in the presence of high doping. The impact of the distribution of BGN between the conduction band and the valence band on the simulated cut-off frequency versus bias current density characteristics is also addressed.

Keywords

Ge-Si alloys; energy gap; heavily doped semiconductors; heterojunction bipolar transistors; semiconductor device models; semiconductor materials; DC characteristics; DESSIS; MEDICI; RF characteristics; SiGe; bias current density; conduction band; cut-off frequency; device simulation; heavy-doping induced band-gap narrowing; high base doping; high doping; modeling; scaled SiGe HBTs; valence band; Doping; Germanium silicon alloys; Medical simulation; Photonic band gap; Radio frequency; Radiofrequency identification; Semiconductor process modeling; Silicon germanium; Statistical distributions; Statistics;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/TED.2003.813237

Filename

1210798