ABSTRACT
Floating regions in device simulation are a potential source of convergence problems due to the singular character of the matrices that need to be inverted during the iteration towards the solution in the Newton-Raphson method. Floating regions typically occur if there exist domains where charge can get trapped. This chapter introduces a method for solving electromagnetic field problems by including an additional scalar ghost field that needs to be obtained as part of the solution method. In general-purpose electromagnetic field solvers the constitutive laws for the current densities are used in such a way that they reflect the material properties of the underlying domain. In the high-frequency regime there can be currents in a floating domain due to inductance effects as well as conversion of displacement currents in the insulating domains to conductance currents at the surface of metallic floating domains.
