I-MOS Transistor With an Elevated Silicon–Germanium Impact-Ionization Region for Bandgap Engineering

Author

Toh, Eng-Huat ; Wang, Grace Huiqi ; Chan, Lap ; Lo, Guo-Qiang ; Samudra, Ganesh ; Yeo, Yee-Chia

Author_Institution

Dept. of Electr. & Comput. Eng., Nat. Univ. of Singapore

Volume

27

Issue

12

fYear

2006

Firstpage

975

Lastpage

977

Abstract

An impact-ionization MOS (I-MOS) transistor with an elevated impact-ionization region (I-region) and excellent subthreshold swing of 3.2 mV/dec at room temperature is demonstrated. An elevated Si_0.75Ge_0.25 region is integrated and employed to engineer the bandgap and impact-ionization rate in the I-region. Compared to a device with a Si I-region, an I-MOS device with a Si_0.75Ge _0.25 I-region shows significantly enhanced performance due to the smaller bandgap of the I-region and the enhanced impact-ionization rate. For the I-MOS device with a Si_0.75Ge_0.25 I-region, the breakdown voltage is also reduced, and a significant drive current enhancement is achieved at V_G-V_T=1 V and a gate length of 80 nm

Keywords

Ge-Si alloys; MOSFET; energy gap; impact ionisation; semiconductor device breakdown; 80 nm; I-MOS transistor; Si_0.75Ge_0.25; bandgap engineering; breakdown voltage; elevated impact-ionization region; subthreshold swing; CMOS integrated circuits; Implants; Ionization; MOSFETs; Photonic band gap; Power supplies; Reliability engineering; Subthreshold current; Temperature; Threshold voltage; Impact ionization; impact-ionization MOS (I-MOS); silicon–germanium; subthreshold swing;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2006.886708

Filename

4016205