Structure and stability of alternative gate dielectrics for Si CMOS

Author

Stemmer, Susanne ; Yang, Yan ; Li, Youli ; Foran, Brendan ; Lysaght, Patrick S. ; Gisby, John ; Taylor, Jeff R. ; Streiffer, Stephen K. ; Fuoss, Paul ; Seifert, Soenke ; Zhu, Wenjuan ; Ma, T.P.

Author_Institution

Mater. Dept., California Univ., Santa Barbara, CA, USA

fYear

2003

fDate

10-12 Dec. 2003

Firstpage

60

Lastpage

61

Abstract

The thermodynamic analysis of both interfacial SiO₂ and silicide reactions, and phase separation of HfO₂ and ZrO₂ are performed. The analysis includes gaseous species, because typical gate dielectrics are ultra-thin layers and diffusivities for species from the surrounding atmosphere, such as oxygen, may be high. Calculations for the ZrO₂-SiO₂ show that compositions between ∼45 mol% and ∼90 mol% SiO₂ lie within the metastable extension of the spinodal at typical annealing temperatures of 1000 C. Grazing-incidence small-angle X-ray scattering (GISAXS) and high-resolution transmission electron microscopy (HRTEM) are used to investigate phase separated microstructure in hafnium silicate films after rapid thermal annealing between 700 and 1000 C.

Keywords

CMOS integrated circuits; X-ray scattering; crystal microstructure; dielectric thin films; elemental semiconductors; hafnium compounds; phase separation; rapid thermal annealing; silicon; silicon compounds; thermodynamic properties; transmission electron microscopy; zirconium compounds; 700 to 1000 C; HRTEM; HfO₂; Si; Si CMOS; SiO₂; ZrO₂; alternative gate dielectrics structure; annealing; gaseous species; grazing incidence small angle X-ray scattering; high-resolution transmission electron microscopy; interfacial reactions; metastable extension; phase separated microstructure; phase separation; rapid thermal annealing; silicide reactions; thermodynamic analysis; ultra thin layers; Atmosphere; Dielectrics; Hafnium oxide; Metastasis; Performance analysis; Rapid thermal annealing; Silicides; Stability; Temperature; Thermodynamics;

fLanguage

English

Publisher

ieee

Conference_Titel

Semiconductor Device Research Symposium, 2003 International

Print_ISBN

0-7803-8139-4

Type

conf

DOI

10.1109/ISDRS.2003.1271995

Filename

1271995