The solar energy as one of the new energy sources and a regenerated energy is abundant and pollution-free. Most photovoltaic devices (solar cells) sold in the market today are based on silicon wafers, the so-called "first generation" technology. The market at present is on the verge of switching to a "second generation" of thin film solar cell technology which offers prospects for a large reduction in material costs by eliminating the costs of the silicon wafers. Cadmium telluride (CdTe), amorphous silicon (a-Si) and copper indium gallium selenide (CIGS) are three thin film technologies which have achieved commercial production. This chapter gives the review of the CIGS solar cells regarding the heterostructures, materials, technology and research advances. It also states the key findings in our research and provides suggestions for future research.
Part of the book: Nanostructured Solar Cells