Band-to-Band Tunneling in Ge-Rich SiGe Devices

Author

Obradovic, Borna ; Bowen, Robert C. ; Rodder, Mark S.

Author_Institution

Adv. Logic Lab., Samsung Semicond., Inc., Austin, TX, USA

Volume

35

Issue

4

fYear

2014

fDate

Apr-14

Firstpage

473

Lastpage

475

Abstract

Germanium is one of the promising materials for future CMOS technologies, due to its high carrier mobility and low Schottky barrier height (for PMOS). However, the presence of a small direct gap (in addition to the main indirect gap at the L-point) can result in significant band-to-band tunneling (BTBT), even at low voltages. If not remedied, it is easily the dominant BTBT mechanism. In this letter, the dependence of BTBT on the alloy composition in Ge-rich SiGe is studied using detailed simulation of the bandstructure. It is shown that even a very low stoichiometric fraction of Si in a FinFET results in a dramatic reduction of direct BTBT, much more so than in a corresponding p-i-n diode.

Keywords

CMOS integrated circuits; Ge-Si alloys; MOSFET; energy gap; p-i-n diodes; semiconductor materials; stoichiometry; tunnelling; CMOS technologies; FinFET; Ge-rich SiGe devices; SiGe; alloy composition; band structure; band-to-band tunneling; p-i-n diode; stoichiometric fraction; Computational modeling; Field effect transistors; P-i-n diodes; Silicon; Silicon germanium; Tunneling; Tunneling; double gate FET; leakage currents; p-i-n diodes;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2014.2299282

Filename

6747330