Study of interface charge densities for ZrO2 and HfO2 based metal-oxide-semiconductor devices

Abstract

A thickness-dependent interfacial distribution of oxide charges for thin metal oxide semiconductor (MOS) structures using high-k materials ZrO2 and HfO2 has beenmethodically investigated. The interface charge densities are analyzed using capacitance-voltage (C-V) method and also conductance (G-V) method. It indicates that, by reducing the effective oxide thickness (EOT), the interface charge densities (Dit) increases linearly. For the same EOT, Dit has been found for the materials to be of the order of 1012cm-2eV-1 and it is originated to be in good agreement with published fabrication results at p-type doping level of 1 ? 1017cm-3. Numerical calculations and solutions are performed by MATLAB and device simulation is done by ATLAS.