Effective Electron Mobility Reduced by Remote Charge Scattering in High-κ Gate Stacks

The mobility reduction in high-κ gate stacks is discussed in terms of remote charge scattering. The mobility is recovered by growing an additional layer of SiO 2 at the interface between the high-κ dielectric and the silicon substrate. A good explanation for this finding is that the Coulomb potential which is induced by the fixed charge at the dielectric/SiO 2 interface is responsible for the scattering of electrons.