Publication Type : Journal Article
Publisher : Applied Physics Letters
Source : Applied Physics Letters, Volume 81, p.2593 (2002)
Url : http://adsabs.harvard.edu/abs/2002ApPhL..81.2593K
Keywords : Dielectric thin films, Diffusion, Elements oxides nitrides borides carbides chalcogenides etc., heterostructures, interface formation, interfaces, Kinetics of defect formation and annealing, Nanostructures
Campus : Amritapuri
School : School of Engineering
Department : Electronics and Communication
Year : 2002
Abstract : Hafnium oxynitride (HfOxNy) gate dielectric was prepared using reactive sputtering followed by postdeposition annealing at 650 °C in a N2 ambient. Nitrogen incorporation in the dielectric was confirmed by x-ray photoelectron spectroscopy analysis. In comparison to HfO2 of the same physical thickness, HfOxNy gate dielectric showed lower equivalent oxide thickness (EOT) and lower leakage density (J). Even after a high-temperature postmetal anneal at 950 °C, an EOT of 9.6 Å with J of 0.8 mA/cm2 @-1.5 V was obtained. In contrast, J of ˜20 mA/cm2 @-1.5 V for HfO2 with an EOT of 10 Å was observed. The lower leakage current and superior thermal stability of HfOxNy can be attributed to the formation of silicon-nitrogen bonds at the gate dielectric/Si interface and strengthened immunity to oxygen diffusion by the incorporated nitrogen.
Cite this Research Publication : C. S. Kang, Cho, H. - J., Onishi, K., Nieh, R., Choi, R., Dr. Sundararaman Gopalan, Krishnan, S., Han, J. H., and Lee, J. C., “Bonding states and electrical properties of ultrathin HfO$_x$N$_y$ gate dielectrics”, Applied Physics Letters, vol. 81, p. 2593, 2002.