Flexible Electromagnetic Modeling of SMM Setups with FE and FDTD Methods

This paper presents FDTD and FEM modeling of two different types of structures representative of industrial scanning microwave microscopy (SMM) material measurements. The first structure is based on a dielectric resonator where the frequencies of whispering gallery modes have to be known with relative errors below 10−4. Herein, this accuracy has been demonstrated using a FEM code adapted to dielectric anisotropy with hybrid usage of vectoral and nodal elements and FDTD code run in a three-step procedure. The second SMM structure consists of a conductive fine tip with radius 25 nm at a certain height from the sample. The numerical modeling is based on time domain FE (TD-FEM) and FDTD and it extracts the scattering parameters from conductive or dielectric samples. The results are in qualitative agreement and further work on calibration to the port impedance of the experimental setup is currently continued.