Abstract: A semiconductor assembly is described with a thin metal oxide layer interposed between a transparent conductive oxide and an amorphous silicon layer, along with methods for making this structure. The metal oxide layer has a refractive index or range of refractive indices intermediate between that of the transparent conductive oxide and the amorphous silicon layer, and thus tends to reduce reflection at the interface. Such a layer can be used at the light-facing surface of a light-sensitive device such as a photovoltaic cell to maximize the amount of incident light entering the cell. Titanium oxide is a suitable metal oxide, and has a refractive index between those of silicon and of both indium tin oxide and aluminum-doped zinc oxide, two common transparent conductive oxides.