Increasing threshold voltage variation due to random telegraph noise in FETs as gate lengths scale to 20 nm

Author

Tega, N. ; Miki, H. ; Pagette, F. ; Frank, D.J. ; Ray, A. ; Rooks, M.J. ; Haensch, W. ; Torii

Author_Institution

Semicond. Innovation Res. Project, Hitachi America Ltd., Yorktown Heights, NY, USA

fYear

2009

fDate

16-18 June 2009

Firstpage

50

Lastpage

51

Abstract

The statistical distribution of random telegraph noise (RTN) has been measured and characterized in scaled PDSOI FETs down to 20 nm gate length. Statistical analysis of RTN in >15 thousand nFETs shows temperature-independent long-tailed non-Gaussian distributions of noise amplitudes. Treated as equivalent threshold voltage variation (DeltaV_th), the RTN distributions appear log-normal, with the DeltaV_th reaching >70 mV for the smalles devices. Because of the log-normal distribution, it appears that RTN V_th variations may exceed random dopant fluctuation (RDF) V_th variations at the ~3 sigma level in the 22 nm generation, making RTN a very serious threat to SRAM stability at 22 nm and beyond.

Keywords

SRAM chips; circuit noise; circuit stability; field effect transistors; statistical distributions; FET; SRAM stability; gate lengths; noise amplitudes; non-Gaussian distributions; random telegraph noise; size 22 nm; statistical analysis; statistical distribution; threshold voltage variation; FETs; Fluctuations; Length measurement; Log-normal distribution; Noise level; Noise measurement; Statistical analysis; Statistical distributions; Telegraphy; Threshold voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

VLSI Technology, 2009 Symposium on

Conference_Location

Honolulu, HI

Print_ISBN

978-1-4244-3308-7

Type

conf

Filename

5200631