NOVELTY - Preparing an ink involves mixing a solution of selenium in ethylene diamine solvent with a solution of at least one metal salt selected from an indium salt or a gallium salt in at least one solvent including an organic amide.    USE - For preparing an ink for forming a solid precursor on a substrate, particularly metal organic liquid precursor inks for the deposition of In-Se, Ga-Se and/or In-Ga-Se films (claimed) which are useful in the fabrication of copper indium diselenide (CIS) and/or copper indium gallium diselenide (CIGS) light absorbing materials for solar cells.    ADVANTAGE - The methods of making the liquid precursor inks can produce a liquid based material or composition that does not contain hydrazine and can be used in deposition techniques that are easier, more efficient and more cost effective to use than solid based deposition techniques such as vacuum deposition. The present method eliminates the use of hydrazine as a solvent, thus eliminating all procedures known to be used in handling and removing hydrazine. The resulting ink is hydrazine-free, thereby greatly enhancing safety and reducing costs of the process of forming the thin films. The hydrazine-free liquid precursor inks permit deposition of solid precursors in a safer and more cost effective manner than those, which contain hydrazine. In addition, the present method produces liquid precursor inks with higher precursor (i.e. indium selenide, gallium selenide and indium gallium selenide) concentration levels, thus reducing the time necessary for generating the solid precursor.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) forming a solid precursor on a substrate involving applying the ink to a surface of the substrate; and subjecting the ink to a heating regime for a time to solidify the ink on the substrate in the form of the solid precursor; and    (2) a composition comprising ink including a solution of selenium in ethylene diamine solvent and a solution of at least one metal salt selected from an indium salt or a gallium salt in at least one solvent including an organic amide.