Finite-Element Modeling and Quantitative Measurement Using Scanning Microwave Microscopy to Characterize Dielectric Films

Scanning Microwave Impedance Microscopy (sMIM) can be used to characterize dielectric thin films and to quantitatively discern film thickness differences. FEM modeling of the sMIM response provides understanding of how to connect the measured sMIM signals to the underlying properties of the dielectric film and its substrate. Modeling shows that sMIM can be used to characterize a range of dielectric film thicknesses spanning both low-k and medium-k dielectric constants. A model system consisting of SiO2 thin films of various thickness on silicon substrates is used to illustrate the technique experimentally.