Reflection and absorption of light by a thin semiconductor film

Reflection and absorption of light by a thin semiconductor film are investigated using the local field method taking into account local field inhomogeneities. The effective susceptibility of such films (which has the meaning of the response of the system to an external field) is calculated. The reflection coefficients are obtained as functions of frequency and angle of incidence of light for homogeneous films and films with a non-uniform distribution of impurities along the film depth. It is shown that, at a certain frequency of an incident light wave, which corresponds to a certain type of excitations in a film, the reflection is maximum. This frequency depends on the depth profile of compensating impurities. The problem of correct determination of the absorption of external field energy by a thin film is discussed. (C) 2004 MAIK "Nauka/Interperiodica".