NOVELTY - The method comprises formulating (352) an ink of particles, coating (354) a substrate with the ink to form a precursor layer, and processing (356) the precursor layer to form a dense film. The particles ( greater than or equal to 50) are flakes of which each has a non-spherical and planar shape and contains an element of group IB, IIIA and/or VIA contained in the ink such that the ink has a desired stoichiometric ratio of the elements. The flakes have a longest dimension of 5 microns to 500 nm and an aspect ratio of greater than or equal to 15. The planar shape of the flakes creates greater surface area contact between adjacent flakes.    USE - The method is useful for fabricating thin film solar cells based on IB-IIIA-VIA compounds.    ADVANTAGE - The method is capable of economically, efficiently and reliably fabricating the solar cells with enhanced power conversion efficiencies and good structural and electronic quality, and reduces the surface tension at interface between nanoflakes in the ink and a carrier fluid thus improving the dispersion quality of the solar cell.    DETAILED DESCRIPTION - The method comprises formulating (352) an ink of particles, coating (354) a substrate with the ink to form a precursor layer, and processing (356) the precursor layer to form a dense film. The particles ( greater than or equal to 50) are flakes of which each has a non-spherical and planar shape and contains an element of group IB, IIIA and/or VIA contained in the ink such that the ink has a desired stoichiometric ratio of the elements. The flakes have a longest dimension of 5 microns to 500 nm and an aspect ratio of greater than or equal to 15. The planar shape of the flakes: creates greater surface area contact between adjacent flakes that allow the dense film to form at an annealing temperature of less than or equal to 50 degrees C as compared to a film made from a precursor layer using an ink of spherical nanoparticles identical to the ink; creates a higher packing density of 95% in the precursor layer that forms the dense film; has grain sizes of 1 mu m in a dimension in the semiconductor absorber of a photovoltaic device; and provides a material property to allow for even distribution of group IIIA material throughout in the dense film as compared to a film made from a precursor layer using an ink of spherical nanoparticles. The nanoparticles have a similar material composition. The flakes have length of less than 1 microns and a thickness of less than 50 nm, are comprised of a binary alloy and a ternary alloy of group IB and IIIA elements and a quaternary alloy of group IB, IIIA, and/or VIA elements.    DESCRIPTION OF DRAWING(S) - The diagram shows a flowchart of a method of fabricating solar cells.    Creating nanoflakes (350)    Washing nanoflakes (351)    Formulating ink containing nanoflakes (352)    Coating a substrate to form precursor layer (354)    Removing dispersant and/or other residual of the precursor layer (355)    Processing precursor layer to form dense film. (356)