Revisiting Schottky barriers for CIGS solar cells: Electrical characterization of the Al/Cu(InGa)Se2 contact

Devices based on a metal-semiconductor contact are potential candidates for the fabrication of photovoltaic cells as long as the corresponding junctions exhibit good rectifying properties and a low contact resistance. This article presents a detailed electrical analysis of the aluminum/CIGS system. The values of the representative parameters of the quality of the diode such as the barrier height, the ideality factor and the series resistance are deduced from an analytical study of the intensity-voltage characteristics. It is concluded that this system does fulfill the necessary (but not sufficient) basic conditions for being used in photovoltaic cells.