Author :
Young, C.D. ; Heh, D. ; Nadkarni, S. ; Choi, R. ; Peterson, J.J. ; Harris, H.R. ; Sim, J.H. ; Krishnan, S.A. ; Barnett, J. ; Vogel, E. ; Lee, B.H. ; Zeitzoff, P. ; Brown, G.A. ; Bersuker, G.
Abstract :
Constant voltage stress (CVS) combined with charge pumping (CP) measurements was applied to study trap generation phenomena in SiO2 /HfO2/TiN stacks. Using the analysis for frequency-dependent CP data developed to address depth profiling of the electron traps, we have determined that the voltage stress-induced generation of the defects contributing to threshold voltage instability in high-k gate stacks occurs primarily within the interfacial SiO2 layer (IL) on the as-grown "precursor" defects most likely caused by the overlaying HfO2 layer. These results point to the IL as a major focus for reliability improvement of high-k stacks
Keywords :
dielectric materials; electron traps; hafnium compounds; interface states; reliability; silicon compounds; titanium compounds; SiO2-HfO2-TiN; SiO2/HfO2/TiN stacks; charge pumping measurements; constant voltage stress; depth profiling; electron traps; high-k gate stacks; interfacial layer; reliability improvement; threshold voltage instability; trap generation detection; voltage stress-induced generation; Charge measurement; Charge pumps; Current measurement; Electron traps; Hafnium oxide; High K dielectric materials; High-K gate dielectrics; Stress measurement; Threshold voltage; Tin;
