Investigation and Localization of the SiGe Source/Drain (S/D) Strain-Induced Defects in PMOSFET With 45-nm CMOS Technology

Author

Cheng, C.Y. ; Fang, Y.K. ; Hsieh, J.C. ; Hsia, H. ; Sheu, Y.M. ; Lu, W.T. ; Chen, W.M. ; Lin, S.S.

Author_Institution

Dept. of Electr. Eng. & Adv., Nat. Cheng Kung Univ., Tainan

Volume

28

Issue

5

fYear

2007

fDate

5/1/2007 12:00:00 AM

Firstpage

408

Lastpage

411

Abstract

In this letter, for the first time, the defects that are induced from the SiGe strain source/drain (S/D) in PMOSFET with 45-nm CMOS technology were investigated in detail. With the conventional charge pumping and the improved low gate-leakage gated-diode (L²- GD) measurements, we find that the uniaxial compressive stress from SiGe S/D generates a large number of acceptorlike interface states at the gate oxide/extension of S/D interface, thus enhancing the leakage current. Compared to defects that are caused by the relaxed Si_1-xGe_x on the conventional graded Si_1-xGe_x buffer layer, the SiGe S/D experienced results that are more serious. The acceptorlike interface states are suspected to be the Si dangling bonds broken by the stress. A schematic model is proposed to illustrate the effect of the stress comprehensively

Keywords

CMOS integrated circuits; Ge-Si alloys; MOSFET; leakage currents; 45 nm; CMOS technology; PMOSFET; SiGe; charge pumping; leakage current; low gate-leakage gated-diode measurements; source/drain strain-induced defects; uniaxial compressive strain; CMOS technology; Capacitive sensors; Charge measurement; Charge pumps; Current measurement; Germanium silicon alloys; Interface states; MOSFET circuits; Silicon germanium; Stress; Low gate-leakage gated-diode $(hbox{L}^{2}$ –$hbox{GD})$; SiGe; uniaxial compressive strain;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2007.895446

Filename

4160011