a novel 2 step solid source deposition method to form an absorber layer in the manufacture for cigs solar modules . 2 - step refers to a first step of deposition of metals followed by second step of selenization of the metal stack . metals are first deposited and then selenized in an adjacent chamber . differential pumping is used to control egress of se vapor into the sputtering region and prevent contamination of the targets . products made by the method demonstrate comparable quality and performance to those produced by current processing techniques . the 2sss method provides means for attaining improved uniformity of large area films which improves yield and cost - effectiveness .