The present invention relates to a precursor solution for forming a semiconductor thin film on the basis of CIS, CIGS or CZTS by printing, comprising metal complexes of at least two different metal cations, wherein the first metal cation is a copper cation and the second is selected from the group consisting of (i) In, (ii) a combination of In and Ga, and (iii) a combination of Zn and Sn, wherein Cu and Sn, if Sn is present, is/are complexed by at least one sulfur or selenium containing anionic complex ligand or polyanion selected from the group consisting of trithiocarbonate, polysulfide or the selenium analogs thereof. If In, In with Ga, or Zn is present, their cations are complexed by an excess of trithiocarbonate and/or triselenocarbonate, and a solvent. A method for preparing such solutions and their use for manufacturing a solar cell or optoelectronic device is provided.