Chinese Science Bulletin

, Volume 57, Issue 22, pp 2872–2878 | Cite as

Interface dipole engineering in metal gate/high-k stacks

  • AnPing Huang
  • XiaoHu Zheng
  • ZhiSong Xiao
  • Mei Wang
  • ZengFeng Di
  • Paul K. Chu
Open Access
Review Condensed Matter Physics

Abstract

Although metal gate/high-k stacks are commonly used in metal-oxide-semiconductor field-effect-transistors (MOSFETs) in the 45 nm technology node and beyond, there are still many challenges to be solved. Among the various technologies to tackle these problems, interface dipole engineering (IDE) is an effective method to improve the performance, particularly, modulating the effective work function (EWF) of metal gates. Because of the different electronegativity of the various atoms in the interfacial layer, a dipole layer with an electric filed can be formed altering the band alignment in the MOS stack. This paper reviews the interface dipole formation induced by different elements, recent progresses in metal gate/high-k MOS stacks with IDE on EWF modulation, and mechanism of IDE.

Keywords

high-k dielectrics metal gate interface dipole MOS stack effective work function 

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Copyright information

© The Author(s) 2012

Authors and Affiliations

  • AnPing Huang
    • 1
  • XiaoHu Zheng
    • 1
  • ZhiSong Xiao
    • 1
  • Mei Wang
    • 1
  • ZengFeng Di
    • 2
  • Paul K. Chu
    • 3
  1. 1.Department of PhysicsBeihang UniversityBeijingChina
  2. 2.Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghaiChina
  3. 3.Department of Physics and Materials ScienceCity University of Hong KongTat Chee Avenue, Kowloon, Hong KongChina

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