TECHNOLOGY FOCUS - ELECTRONICS - Preferred Composition: The one layer of semiconductor particles comprises 1-10, preferably 3-5 monolayers of semiconductor particles. The ratio of water to alcohol is 0.5-2 (preferably 1). Preferred Parameter: The porous semiconductor film has a thickness of 1-100 microns. The suspension has an electrical conductivity which is adjusted for use by the presence of an acid, a base and/or a diluent liquid, e.g. an alcohol. Preferred Material: The alcohol is 1-4 C alcohol, preferably ethanol, propanol, and/or isopropanol.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The method also comprises drying and/or sintering the printed porous semiconductor film, forming a dried and/or sintered porous semiconductor film. The suspension of semiconductor particles is applied in several stages, each stage comprising application of one layer only. The suspension of semiconductor particles is applied in spots of defined size(s), so that the resulting printed and/or dried and/or sintered porous semiconductor film is a textured film. The ink-jet printing is performed at 1-200 (preferably 50-150) degrees C. Preferred Material: The acid is nitric acid. The semiconductor particles are oxide particle, preferably titanium dioxide (TiO2) particles. Preferred Composition: The semiconductor particles are present at less than or equal to 10 (preferably 3) weight %.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The method also comprises drying and/or sintering the printed porous semiconductor film, forming a dried and/or sintered porous semiconductor film. The suspension of semiconductor particles is applied in several stages, each stage comprising application of one layer only. The suspension of semiconductor particles is applied in spots of defined size(s), so that the resulting printed and/or dried and/or sintered porous semiconductor film is a textured film. The ink-jet printing is performed at 1-200 (preferably 50-150) degrees C. Preferred Material: The acid is nitric acid. The semiconductor particles are oxide particle, preferably titanium dioxide (TiO2) particles. Preferred Composition: The semiconductor particles are present at less than or equal to 10 (preferably 3) weight %.