Barrier coatings for thin film solar cells

This program has involved investigations of the stability of cadmium telluride (CdTe) and copper-indium-gallium-diselenide (CIGS) solar cells under damp heat conditions and effects of barrier coatings. Barrier coating technology developed at PNNL for organic light emitting diodes (OLEDs) was used to investigate approaches to encapsulation of the two types of thin film solar cells. Moisture barriers consisting of multi-layer coatings involving alternating layers of polymer and aluminum oxide were deposited directly onto the front surface of CIGS cells and the rear surface of CdTe devices, with the front surface defined by the light receiving side of the cell. Most of the studies were conducted with directly deposited barrier coatings.