thin film solar cell
Thin film solar cells are solar cells manufactured using thin film technology. They can be made from polycrystalline and amorphous silicon, although elemental compounds of various chemical elements such as cadmium, indium, gallium and selenium are often used.
For example, thin-film solar cells are made of cadmium telluride( CdTe), copper indium selenide( CIS), copper indium gallium selenide ( CIGS) or gallium arsenide( GaAs), which are vapor-deposited onto a substrate made of glass or a stainless steel foil with a layer thickness of a few micrometers. On the side facing the sun, a thin layer of transparent conductive oxide( TCO) is applied as an electrode. This creates a larger solar unit that is cut into thinner strips with lasers. The layer thickness is only a few micrometers, 0.5 µm to 2 µm.
In the production of thin solar films, thin film technology has the advantages that it requires less semiconductor material, the manufacturing processes and semiconductor materials are inexpensive, and the solar module is inherently flexible. In addition, thin film solar cells are characterized by lower power consumption at high temperatures and better performance in low light conditions. The efficiency is around 7 % to 10 %. Efficiencies of around 25 % have already been achieved for CIGS solar cellsin development laboratories.
Thin-film solar cells can be manufactured inexpensively and have a cost advantage over silicon solar cells.