Quantifying the heat affected zone in laser scribing of thin film solar cells

Laser scribing is a method for partitioning thin film solar panels into a series of mini-modules. While glass-side laser scribing is meant to be a thermally-induced mechanical material removal method, significant thermal damage may occur if the process is not properly designed. No approach has been developed yet to conveniently measure the size of the heat affected zone. Kelvin probe force microscopy was proposed and used to measure the heat affected zone via changes in the work function of the material. It was found that mechanically dominated material removal yields the smallest HAZ while also achieving a satisfactory electrical isolation.