Real-time optimization of anti-reflective coatings for CIGS solar cells

In this paper, we describe a model allowing for the optimization of the thickness of the anti-reflective (AR) coating for Cu (In
_1-x
Ga
_x
) Se
₂
(CIGS) solar cells. This model is based on an optical model developed based on transfer matrix theory as well as accurate measurement of the dielectric function and thickness of each layer in the stack by in-situ spectroscopic ellipsometry. The thickness of the AR coating was then optimized in real time to optically enhance the performance of the device for various device configurations, including CIGS thickness and AZO thickness. The influence of the substrate temperature on the properties of the AR coating and the device was also studied.