Expressions for the net generation rate of electron-hole pairs under illumination and the ideal Current-voltage (

) characteristics of a specific type of thin-film solar cell are derived. The thin-film configuration consists of an n- on p-type semiconductor with a rough upper surface (which is approximated by a distribution of smooth microscopic surfaces or facets randomly oriented) and a diffusive, perfectly reflecting lower surface. This configuration leads to a significant enhancement of the radiation flux in the film and theoretically to a higher collection probability and conversion efficiency compared to the conventional solar cell based on a much thicker crystalline film. The

characteristics are finally expressed in terms of a set of double integrals in a form suitable for numerical analysis.