Title :
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
fDate :
5/1/2007 12:00:00 AM
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 Si1-x Gex on the conventional graded Si1-xGex 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;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2007.895446
