Title :
On the impact of TiN film thickness variations on the effective work function of poly-Si/TiN/SiO2 and poly-Si/TiN/HfSiON gate stacks
Author :
Singanamalla, R. ; Yu, H.Y. ; Pourtois, G. ; Ferain, I. ; Anil, K.G. ; Kubicek, S. ; Hoffmann, T.Y. ; Jurczak, M. ; Biesemans, S. ; De Meyer, K.
Author_Institution :
Interuniv. Microelectron. Center, Heverlee, Belgium
fDate :
5/1/2006 12:00:00 AM
Abstract :
The impact of TiN film thickness variations on the effective work function (WF) of poly-Si/TiN/SiO2 and poly-Si/TiN/HfSiON interfaces has been investigated. The electrical signatures of these gate stacks indicate that the concentration of Hf-Ti and Ti-Si bonds at the (poly-Si/TiN)/HfSiON and (poly-Si/TiN)/SiO2 interface plays a significant role on the control of the gate stacks´ WF. The density of these interfacial bonds and the related work function changes are correlated to the degree of nucleation of the TiN film on the dielectric.
Keywords :
Fermi level; dielectric thin films; hafnium compounds; interface structure; nucleation; semiconductor-metal boundaries; silicon; silicon compounds; titanium compounds; work function; Fermi-level pinning; Si-TiN-HfSiON; Si-TiN-SiO2; atomic layer deposition; effective work function; electrical signatures; film nucleation; film thickness variations; gate stacks; interfacial bonds; Chemical vapor deposition; Chemistry; Dielectric films; Electrodes; Lead compounds; Microelectronics; Physics; Threshold voltage; Tin; Wave functions; Atomic layer deposition (ALD); Fermi-level pinning (FLP); HfSiON; effective work function (WF); metal gate; poly-Si/TiN;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2006.872916
