Two-step annealing effects on ultrathin EOT higher-k (k = 40) ALD-HfO2 gate stacks

Author

Morita, Yukinori ; Migita, Shinji ; Mizubayashi, Wataru ; Masahara, Meishoku ; Ota, Hiroyuki

Author_Institution

Green Nanoelectron. Center (GNC), Nat. Inst. of Adv. Ind. Sci. & Technol. (AIST), Tsukuba, Japan

fYear

2012

fDate

17-21 Sept. 2012

Firstpage

81

Lastpage

84

Abstract

We fabricated ultrathin HfO₂ gate stacks of very high permittivity by atomic layer deposition (ALD) and novel two-step post-deposition annealing (PDA) technique. First, no-cap PDA degasses residual contaminations in ALD layer, and second, Ti-cap PDA enhances permittivity of HfO₂ by generating cubic crystal phase without SiO₂ interfacial layer growth. Using these techniques, the dielectric constant of the ALD-HfO₂ can be enhanced to ~40, and a 0.3 nm equivalent oxide thickness is obtained.

Keywords

annealing; atomic layer deposition; hafnium compounds; permittivity; ALD gate stack; ALD layer; HfO₂; PDA technique; Ti-cap PDA; atomic layer deposition; cubic crystal phase; dielectric constant; equivalent oxide thickness; no-cap PDA; permittivity; residual contamination; size 0.3 nm; two-step annealing effect; two-step postdeposition annealing; ultrathin EOT; ultrathin gate stack; Annealing; Hafnium compounds; High K dielectric materials; Logic gates; Permittivity; Silicon; Tin;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State Device Research Conference (ESSDERC), 2012 Proceedings of the European

Conference_Location

Bordeaux

ISSN

1930-8876

Print_ISBN

978-1-4673-1707-8

Electronic_ISBN

1930-8876

Type

conf

DOI

10.1109/ESSDERC.2012.6343338

Filename

6343338