Title :
Statistical analysis of soft breakdown in ultrathin gate oxides
Author :
Mizubayashi, W. ; Yoshida, Y. ; Miyazaki, S. ; Hirose, M.
Author_Institution :
Dept. of Electr. Eng., Hiroshima Univ., Japan
Abstract :
It is found that the Weibull slope /spl beta/ of the time-to-soft breakdown (t/sub SBD/) distributions coincides with that of time-to-hard breakdown (t/sub BD/) distributions over the oxide thickness range 1.9-4.8 nm, and /spl beta/ linearly decreases with decrease of oxide thickness. Such decrease in /spl beta/ of both t/sub SBD/ and t/sub BD/ distributions is well correlated to measured Si-O-Si bond angle reduction induced by compressive stress in the SiO/sub 2/ network. These results suggest that soft breakdown (SBD) as well as hard breakdown (HBD) are triggered by a common physical mechanism such as defect generation from strained Si-O-Si bonds.
Keywords :
MOS capacitors; MOSFET; Weibull distribution; bond angles; dielectric thin films; integrated circuit reliability; integrated circuit testing; semiconductor device breakdown; statistical analysis; 1.9 to 4.8 nm; MOS capacitors; MOSFET; Si-O-Si bond angle reduction; SiO/sub 2/ network; SiO/sub 2/-Si; Weibull slope; compressive stress; defect generation; hard breakdown; oxide thickness; oxide thickness range; physical mechanism; soft breakdown; statistical analysis; strained Si-O-Si bonds; time-to-hard breakdown distribution; time-to-soft breakdown distribution; ultrathin gate oxides; Bonding; Compressive stress; Electric breakdown; Goniometers; MOS capacitors; MOSFETs; Probability; Statistical analysis; Stress measurement; Weibull distribution;
Conference_Titel :
VLSI Technology, 2001. Digest of Technical Papers. 2001 Symposium on
Conference_Location :
Kyoto, Japan
Print_ISBN :
4-89114-012-7
DOI :
10.1109/VLSIT.2001.934966
