Abstract
The field solution in a semiconductor based on charge transport model in small-signal analysis is presented to obtain the reflection coefficients for both H-polarization and E-polarization. The field solution incorporates the full set of Maxwell's equations and the equation of motion of the charge carriers based on a drift diffusion model. Two sets of differential equations that describe the field distribution and the charge carrier densities in the semiconductor have been obtained. One set represents the static parts and another represents the dynamic parts. The dynamic set has been solved for unbiased n-type semiconductor substrate backed with a perfect electric conductor (PEC) material when the incident field employed is either of H-polarization or E-polarization. The interaction of the fields and the charge carriers in the semiconductor causes a charge accumulation at the semiconductor-dielectric interface. This charge accumulation at the dielectric-semiconductor interface adds an additional part to the reflection coefficient for H-polarization. This paper showed that this part is due to the normal component of the electric field which causes the charge accumulation. For E-polarization there is no charge accumulation at the semiconductor interface as the electric field is parallel to the semiconductor surface.