Title :
Spatial Distributions of Trapping Centers in HfO2/SiO2 Gate Stack
Author :
Heh, Dawei ; Young, Chadwin D. ; Brown, George A. ; Hung, P.Y. ; Diebold, Alain ; Vogel, Eric M. ; Bernstein, Joseph B. ; Bersuker, Gennadi
Author_Institution :
SEMATECH Inc, Austin, TX
fDate :
6/1/2007 12:00:00 AM
Abstract :
An analysis methodology for charge pumping (CP) measurements was developed and applied to extract spatial distributions of traps in SiO 2/HfO2 gate stacks. This analysis indicates that the traps accessible by CP measurements in the frequency range down to a few kilohertz are located primarily within the SiO2 layer and HfO2/SiO2 interface region. The trap density in the SiO2 layer increases closer to the high-kappa dielectric, while the trap spatial profile as a function of the distance from the high-kappa film was found to be dependent on high-kappa film characteristics. These results point to interactions with the high-kappa dielectric as a cause of trap generation in the interfacial SiO2 layer
Keywords :
charge measurement; dielectric thin films; electron traps; hafnium compounds; leakage currents; silicon compounds; HfO2-SiO2; charge pumping measurements; gate stack; high-k dielectric; high-k film characteristics; interface region; interfacial layer; spatial distributions; trap density; trap generation; trap spatial profile; trapping centers; Charge measurement; Charge pumps; Current measurement; Dielectric materials; Dielectric measurements; Dielectric substrates; Electron traps; Frequency; Hafnium oxide; Threshold voltage; Charge pumping; high-$kappa$ dielectrics; interfacial layer; maximum depth; trap profile;
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2007.896371
