Achievement of 19.7% efficiency with a small-sized Cu(InGa)(SeS)2 solar cells prepared by sulfurization after selenizaion process with Zn-based buffer

We have been focused on improving conversion efficiency of Cu(In, Ga)(Se, S)
2
(CIS)-based solar cell with 30×30cm
²
-sized submodules, and achieved an efficiency of 17.8% up to now[1]. In this report, we will present an achievement of certified 19.7% conversion efficiency with a small-sized single cell (approximately 0.5cm
²
) extracted from a 30×30cm
²
-sized substrate prepared by the sputtering followed by sulfurization after selenization (SAS) method with Zn-based buffer layer. As a leading company of CIS-based solar module, we will keep exploring the potential of CIS-based solar cell both on commercial and lab scales.