COPPER INDIUM GALLIUM SELENIDE PHOTOVOLTAIC MODULES MANUFACTURED BY REACTIVE TRANSFER

In recent years, thin-film photovoltaic companies, especially First Solar with its CdTe technology, managed to realize the low manufacturing cost potential and to grab an increasingly larger market share. Copper Indium Gallium Selenide is the most promising thin-film PV material, having demonstrated the highest energy conversion efficiency in both cells and modules. However, most CIGS manufacturers still face the challenge of delivering a reliable and rapid manufacturing process that can scale effectively and deliver on the promise of this material system. HelioVolt has developed a reactive transfer process for CIGS absorber formation that has the benefits of good compositional control, and a fast high-quality CIGS reaction. The reactive transfer process is a two stage CIGS fabrication method. Precursor films are deposited onto substrates and reusable print plates in the first stage, while in the second stage, the CIGS layer is formed by rapid heating with Se confinement. High quality CIGS films with large grains have been demonstrated on the production line. With 14% cell efficiency and 12% module efficiency, HelioVolt started to commercialize the process on its first 20 MW production line.