Dipole Moment Model Explaining nFET Vt Tuning Utilizing La, Sc, Er, and Sr Doped HfSiON Dielectrics

Author

Sivasubramani, P. ; Böscke, T.S. ; Huang, J. ; Young, C.D. ; Kirsch, P.D. ; Krishnan, S.A. ; Quevedo-Lopez, M.A. ; Govindarajan, S. ; Ju, B.S. ; Harris, H.R. ; Lichtenwalner, D.J. ; Jur, J.S. ; Kingon, A.I. ; Kim, J. ; Gnade, B.E ; Wallace, R.M. ; Bersuke

Author_Institution

SEMATECH, Austin

fYear

2007

fDate

12-14 June 2007

Firstpage

68

Lastpage

69

Abstract

A dipole moment model explaining Vt tuning in HfSiON gated nFETs is proposed and its impact on performance and reliability is presented. La, Sc, Er, and Sr dopants are utilized due to their differing electronegativities and ionic radii. These dopants tune Vt in the range of 250-600 mV. V_t tuning is found to be proportional to the net dipole moment associated with the Hf-O and rare earth (RE)-O bonds at the high-k/SiO₂ interface. The magnitude of this interfacial dipole moment is determined by the electronegativities and ionic radii of the RE cations. LaO_x is the most effective dopant based on Vt, mobility, and reliability,

Keywords

dielectric materials; electric moments; erbium; field effect transistors; hafnium compounds; lanthanum; rare earth compounds; scandium; strontium; HfSiON; HfSiON:Er; HfSiON:Sc; HfSiON:Sr; SiO₂; dielectrics; dipole moment model; gated nFET; interfacial dipole moment; Atherosclerosis; Capacitance; Channel bank filters; Doping; Erbium; High K dielectric materials; High-K gate dielectrics; MOS devices; Semiconductor process modeling; Strontium;

fLanguage

English

Publisher

ieee

Conference_Titel

VLSI Technology, 2007 IEEE Symposium on

Conference_Location

Kyoto

Print_ISBN

978-4-900784-03-1

Type

conf

DOI

10.1109/VLSIT.2007.4339730

Filename

4339730