Wave Reflection Investigation from Semiconductor Surfaces Using First-Order Impedance Boundary Condition

摘要

The reflection coefficient of unbiased n-type semiconductor half-space material when the incident field employed is either of H-polarization or E-polarization using the exact boundary conditions (exact BC) may be complicated and difficult. The approximate boundary conditions have proved to be effective for simplifying the field analysis at semiconductor surfaces where solution would be complicated. So, approximations are in order to simplify the field solution. It is very important to determine the limits and range of validity of the standard impedance boundary condition (SIBC) in a homogeneous semiconductor medium. In the case of planar surfaces, one way to obtain accuracy measurements is by comparing the plane wave reflection coefficients in case of H-polarization and E-polarization. The reflection coefficients for H-polarization and E-polarization based on charge transport model obtained using the exact BC and the approximated reflection coefficients using SIBC are compared together to get the surface impedance. The later is defined by the electromagnetic properties of the scatterer. The surface impedance takes into consideration the dynamics of the charge carriers and the properties of the semiconductor medium.