Statistical Process Control for Cu(In,Ga)(S,Se)2 electrodeposition-based manufacturing process of 60?120cm2 modules up to 14,0% efficiency

The company NEXCIS has developed a 2-step process based on the electrodeposition (ED) of a metallic precursor subsequently annealed to produce Cu(In,Ga)(S,Se)₂ absorbers (CIGS). The metallic precursor is electrodeposited on a highly conductive Mo-based back-contact on glass. It is subsequently reacted in an atmospheric pressure thermal treatment unit under chalcogens atmosphere to produce CIGS cells up to 17.3% externally certified and 60×120cm² modules up to 14.0% aperture area efficiency. These figures demonstrate that a low-cost electrodeposition-based process can successfully produce modules with efficiencies close to the ones obtained from vacuum-based processes such as coevaporation or 2-step Sputtering followed by annealing in hydride gases. Still, to be proven acceptable for production, the developed process must also demonstrate that it is robust and capable of repeatedly generating the same output. In this work, statistical process control techniques are used on more than one hundred 60×120cm² plates to calculate the process capability and show that the ED-based process is well suited for a CIGS production line.