The paper describes ISET's patented non-vacuum process for low cost mass production of CIGS solar cells. In this process, the water based precursor inks of mixed oxides are deposited on various conducting substrates by a variety of non-vacuum coating techniques. The oxides are converted to CIGS by annealing and the device is completed by deposition of CdS by CBD followed by ZnO deposition by MOCVD. Small area solar cells with efficiency >13% have been fabricated by this process. The advantages of this non-vacuum process are: high compositional control of the absorber layer, high materials utilization and low cost.