“…However, hydrozincite formation could still have occurred in case the dissolution was avoided for a longer time, for example for the unpurged water samples. This would have resulted in ZnO:Al layers that still have a closed structure, but have increased potential barriers at the hydrozincite positions, for example at the grain boundaries, leading to increased sheet resistance of the ZnO:Al [6]. Naturally, this would have led to an increased series resistance of the complete CIGS solar cell as well.…”