The effects of biaxially-tensile strain to properties of Si/SiO2 interface states generated by electrical stress

Author

Cai, W.-L. ; Takenaka, Mitsuru ; Takagi, Shinichi

Author_Institution

Sch. of Eng., Univ. of Tokyo, Tokyo, Japan

fYear

2014

fDate

1-5 June 2014

Abstract

In this paper, the effects of biaxially-tensile strain on the properties of Si/SiO₂ interface states generated by FN stress have been systematically investigated. In order to accurately evaluate interface state density (D_it) in MOS capacitors and FETs including strained-Si (sSi)/SiGe hetero-interfaces, the conductance method and the S-factor method have been properly modified. It is found that strain does not strongly change the properties of SiO₂/Si interface states. On the other hand, almost similar ΔD_it and smaller ΔV_th is observed in sSi n-MOSFETs after FN stress. These inconsistent behaviors between ΔD_it and ΔV_th can be explained by the relative shift of the charge neutrality level inside the band gap of strained Si.

Keywords

Ge-Si alloys; MOS capacitors; MOSFET; elemental semiconductors; energy gap; interface states; silicon; silicon compounds; tensile strength; FN stress; MOS capacitors; S-factor method; Si-SiGe; Si-SiO₂; band gap; biaxially-tensile strain; charge neutrality level; conductance method; electrical stress; interface state density; n-MOSFET; strained-Si-SiGe hetero-interfaces; Capacitance; Interface states; Silicon; Silicon germanium; Strain; Stress; charge neutrality level; hetero-interface; interface state; strained Silicon;

fLanguage

English

Publisher

ieee

Conference_Titel

Reliability Physics Symposium, 2014 IEEE International

Conference_Location

Waikoloa, HI

Type

conf

DOI

10.1109/IRPS.2014.6861183

Filename

6861183