Title :
Process optimization for high electron mobility in nMOSFETs with aggressively scaled HfO2/metal stacks
Author :
Narayanan, Vijaykrishnan ; Maitra, K. ; Linder, B.P. ; Paruchuri, V.K. ; Gusev, E.P. ; Jamison, P. ; Frank, M.M. ; Steen, M.L. ; La Tulipe, D. ; Arnold, J. ; Carruthers, R. ; Lacey, D.L. ; Cartier, E.
Author_Institution :
IBM Thomas J. Watson Res. Center, Yorktown Heights, NY, USA
fDate :
7/1/2006 12:00:00 AM
Abstract :
The performance of aggressively scaled (1.4nminv<2.1nm) self-aligned HfO2-based nMOSFETs with various metal gate electrodes (W, TaN, TiN, and TaSiN) is optimized. It is shown that high mobility values, competitive with oxynitride controls (SiON/poly-Si, Tinv∼1.8-2.1nm), can be achieved. Detailed studies of the role of interface states, remote charges in the HfO2 layer, interfacial layer regrowth, and nitrogen-induced charge lead to the conclusion that high-temperature-induced structural modifications near the SiO2/HfO2 interface substantially improve the electron mobility.
Keywords :
MOSFET; electron mobility; hafnium compounds; high-k dielectric thin films; interface states; HfO2; chemical vapor deposition; electron mobility; high-K dielectric; interface states; interfacial layer regrowth; metal gate electrode; nMOSFET; nitrogen-induced charge; process optimization; Chemical vapor deposition; Electrical resistance measurement; Electrodes; Electron mobility; Hafnium oxide; Interface states; MOSFETs; Nitrogen; Thermal degradation; Tin; Chemical vapor deposition (CVD); electron mobility; hafnium oxide; high-; metal gate electrode; titanium nitride (TiN);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2006.876312
