Spectroscopic charge pumping in the presence of high densities of bulk dielectric traps

We demonstrate the extension of the recently developed spectroscopic charge-pumping (CP) technique to high-k gate stacks. To deal with the high density of bulk traps, we develop an experimentally based methodology to remove the bulk trap contribution from the measured CP data. We demonstrate the capability of the spectroscopic CP technique to measure band edge states and show that the traditional U-shaped continuum of band edge states is not intrinsic to Si/SiO₂ interfaces.