Photoelectrochemical test for photovoltaic activity of p-CuInSe₂ films

Photovoltaic cells containing CuInSe₂ are among the most efficient and stable thin film solar cells known at present. We have developed a photoelectrochemical system to characterize the CuInSe₂ component of the device using the junction between CuInSe₂ on metal and liquid electrolyte. A non-aqueous electrolyte containing a redox couple not specifically absorbed onto the semiconductor was used to minimize permanent surface alterations. With this technique the photovoltaic activity was tested with some spatial resolution over the film area and as a function of semiconductor surface treatment.