Title :
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
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;
Conference_Titel :
Solid-State Device Research Conference (ESSDERC), 2012 Proceedings of the European
Conference_Location :
Bordeaux
Print_ISBN :
978-1-4673-1707-8
Electronic_ISBN :
1930-8876
DOI :
10.1109/ESSDERC.2012.6343338
