NOVELTY - Making a photovoltaic absorber layer on a substrate, comprises: (a) providing at least one molecular precursor compound or ink; (b) providing a substrate (10); (c) depositing the compounds or inks onto the substrate; and (d) heating the substrate at 100-650 degrees C in an inert atmosphere, and thus producing a photovoltaic absorber layer (30).    USE - The method is useful for making a photovoltaic absorber layer, which is useful in: a photovoltaic device; and a system for providing electrical power for converting light into electrical energy (all claimed) including solar cells.    ADVANTAGE - The method: provides a photovoltaic absorber layer, which is a thin film having a thickness of 0.001-100 mu m; utilizes molecular precursors, which enhances the formation of a semiconductor and its properties, enhances the processability for solar cell production and the ability to be processed on a variety of substrates including polymers at relatively low temperatures, is stable at ambient temperatures, allows control of the stoichiometry, structure, and ratios of various atoms in a material, layer, or semiconductor, thus enhances control over the structure of a semiconductor material, provides photovoltaic materials and solar cells of high efficiency, and provides chemically and physically uniform semiconductor layers; can be carried out at relatively low temperatures in the preparation of solar cells and other products; and provides photovoltaic absorber layer regardless of the morphology or architecture of the semiconductors or devices.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) a photovoltaic absorber layer made by the method;    (2) a photovoltaic device comprising the photovoltaic absorber layer;    (3) a system for providing electrical power comprising the photovoltaic absorber layer; and    (4) providing electrical power comprising using a system to convert light into electrical energy.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a solar cell.    Substrate (10)    Electrode layer (20)    Absorber layer (30)    Window layer (40)    Transparent conductive layer (50)