Interface Charge Density Measurement for Ultra Thin ZrO2 Material Based MOS Devices Using Conductance Method

The metal oxide semiconductor (MOS) conductance technique has been a key tool for the understanding of electrically active interface states since it was first developed by Nicollian and Brews in the mid 1960's. In this letter the interface charge densities (Dit) are analyzed for ultra thin dielectric material based MOS devices using high-k dielectric material ZrO2 at p-type doping level of 1x1017 cm-3. The Dit have been calculated by a novel approach using conductance method and it indicates that by reducing the thickness of the oxide, the Dit increases and similar increase is also found by replacing SiO2 with ZrO2. Numerical calculations and analytical solutions are performed by MATLAB and device simulation is done by ATLAS, a TCAD tool from Silvaco.