Transport and free carrier electromagnetic phenomena in semiconductor boundary layer: II. Reflectivity with non-normal incidence and surface plasmons

A classical analysis is given of the reflectivity at oblique incidence on semiconductor surfaces. The theory includes the effect of a space charge boundary layer and yields formulae from which one can obtain the dispersion relation for surface plasmons, for which the effects of the boundary layer are particularly important. An application to experimental data on n-InSb gives satisfactory agreement while yielding a plausible estimate of the surface excess ΔN. The electroreflectance is also studied, including numerical evaluations. It is suggested that measurements at almost grazing incidence could yield valuable information on the surface scattering of carriers.