@article{ab08cb102e1a4375af28ffcc34f49508,
title = "Origin of the flatband-voltage roll-off phenomenon in metal/high-k gate stacks",
abstract = "The effect of flatband-voltage reduction [roll-off (R-O)], which limits fabrication options for obtaining the needed band-edge threshold voltage values in transistors with highly scaled metal/high- k dielectric gate stacks, is discussed. The proposed mechanism causing this R-O phenomenon is suggested to be associated with the generation of positively charged oxygen vacancies in the interfacial SiO2 layer next to the Si substrate. The vacancies in the interfacial layer are induced by oxygen outdiffusing into the overlying high- k dielectric. The model is consistent with the variety of observations of R-O dependence on the electrode and substrate type, high- k dielectric composition and thickness, temperature, etc. The model's predictions were experimentally verified.",
author = "Gennadi Bersuker and Park, {Chang Seo} and Wen, {Huang Chun} and K. Choi and Jimmy Price and Patrick Lysaght and Tseng, {Hsing Huang} and O. Sharia and Alex Demkov and Ryan, {Jason T.} and P. Lenahan",
note = "Funding Information: Manuscript received February 4, 2010; revised May 17, 2010; accepted May 19, 2010. Date of current version August 20, 2010. The works of A. Demkov and O. Sharia were supported by the National Science Foundation under Grant DMR-0548182. The review of this paper was arranged by Editor Y.-H. Shih. G. Bersuker, C. S. Park, J. Price, and P. Lysaght are with SEMATECH, Austin, TX 78741 USA. H.-C. Wen was with SEMATECH, Austin, TX 78741 USA. She is now with the Analog Technology Development Group, Texas Instruments Incorporated, Richardson, TX 75080 USA (e-mail: h-wen@ti.com). K. Choi was with SEMATECH, Austin, TX 78741 USA. He is now with the Global Foundries, IBM T. J. Watson Research Center, Yorktown Heights, NY 12524 USA. H.-H. Tseng was with SEMATECH, Austin, TX 78741 USA. He is now with Texas State University, San Marcos, TX 78666 USA. O. Sharia was with the University of Texas at Austin, Austin, TX 78712 USA. He is now with the University of Maryland, College Park, MD 20742 USA. A. Demkov is with the University of Texas at Austin, Austin, TX 78712 USA. J. T. Ryan was with The Pennsylvania State University, University Park, PA 168020 USA. He is now with the National Institute of Standards and Technology, Gaithersburg, MD 20899-8910 USA. P. Lenahan is with The Pennsylvania State University, University Park, PA 168020 USA. Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TED.2010.2051863",
year = "2010",
month = sep,
doi = "10.1109/TED.2010.2051863",
language = "English (US)",
volume = "57",
pages = "2047--2056",
journal = "IEEE Transactions on Electron Devices",
issn = "0018-9383",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "9",
}