Effects of selenization conditions including evaporation temperature of Se source and selenization timeon the properties of CuInSe_2 (CIS) absorber layer fabricated by a non-vacuum coating of a low cost precursorsolution were investigated in this work. Precursor solution was prepared by dissolving Cu(NO)_3 and InCl in methanolwith an atomic ratio of Cu/In=1. The solution was coated onto the Mo/glass substrate with appropriate bindermaterials and the precursor layer was selenized in a vacuum evaporator. In the selenization experiments, as the Seevaporation temperature increased from 150 to 180 °C the Cu/In ratio of the resultant layer selenized for 30 mindecreased from 2 to 1.1, and further increase in Se evaporation temperature did not affect Cu/In ratio anymore.Regarding that the Cu/In ratio of starting solution is 1, it seems that a low Se pressure condition induced the loss ofIn contents presumably by evolution of volatile In-selenide phases and the evolution decreased as the Se evaporationtemperature increased. Selenization time from 15 min to 1 h at a Se evaporation temperature of 200 °C did not affectthe crystalline structures and compositions of the selenized layers, reflecting that the conversion of precursormaterials to CIS was completed in 15 min.
展开▼
