Thin Film Solar Cells

Renewable energy wouldn't be possible without vacuum. One example are Photovoltaics (PV) which are best known as a method for generating electrical power by using solar cells to convert energy from the sun into a flow of electrons by the photovoltaic effect.

How does it work?

There are various types of solar cell technologies - one of the major technologies is based on thin film deposition. The main advantage of this technology is the low material consumption within the solar cell production. Beside materials like Cadmium Telluride (CdTe), Copper-Indium-Gallium-Selenide (CIGS) will be often used for the absorber layers. These layers can be deposited on inflexible substrates like glass or on flexible substrates like metal band or foil or on flexible thin glass and then the substrate is inserted into a big vacuum chamber. In this chamber several PVD processes like sputtering or evaporation take place to generate a multilayered solar cell. To deposit these layers, a vacuum in the range of 10-3 to 10-6 hPa is needed depending on the process. Due to the large surfaces, a high suction speed is inevitable. This vacuum needs to be clean and carbon free to ensure high quality layers.