Leakage current analysis of a real world silicon-silicon dioxide capacitance

It is shown that surface roughness becomes increasingly important as oxide thicknesses decrease. Silicon-silicon dioxide capacitances with thicknesses of 7 nm, 15 nm, and 50 nm are measured with an atomic force microscope (AFM). The height data thusly obtained is used to create three dimensional simulation structures to reproduce measurement data obtained from leakage current measurements. The leakage currents are simulated using the Fowler-Nordheim (FN) tunnelling current model.