CIGS Photovoltaic Glass CIGS (Copper Indium Gallium Selenide) photovoltaic glass is another type of solar glass that utilizes thin-film photovoltaic technology. CIGS solar cells are composed of thin layers of semiconductor materials, including copper, indium, gallium, and selenium. When applied to glass substrates, these materials create a transparent or semi-transparent layer capable of converting sunlight into electricity.