Spatial Distributions of Trapping Centers in HfO₂/SiO₂ Gate Stack

An analysis methodology for charge pumping (CP) measurements was developed and applied to extract spatial distributions of traps in SiO2/HfO2gate 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 SiO2layer and HfO2/SiO2interface region. The trap density in the SiO2layer 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 SiO2layer