Sputtering enables high-speed manufacturing of thin film solar cells

Midsummer, a supplier of production lines for manufacturing of flexible thin film CIGS solar cells, has announced developing a high-speed process for manufacturing of CIGS solar cells utilising sputtering of all layers in the solar cell structure. The company reportedly recently achieved 15% active area efficiency on an entire 225 cm2 solar cell using the sputtering technology.

The company stressed that sputtering the buffer layer was a key achievement, as normally it is deposited with chemicals or by atomic layer deposition. Also, the CIGS layers were sputtered from compound CIGS targets resulting in a very short cycle time, eliminating the need for selenizing the solar cells for several hours.

Midsummer, pointed out that by using sputtering in all processing steps, the process cycles in the manufacturing of solar cells can be drastically shortened, the solar cells can be made cadmium-free and also made on stainless steel substrates suitable for flexible modules – all contributing to a highly competitive method to manufacture thin film CIGS cells with high efficiencies.

It is a completely dry and an all-vacuum process with less stringent requirements for cleanrooms, the company informed.

“Most photovoltaic experts consider thin film flexible solar modules to be the future of solar energy, and I agree,” said Sven Lindström, CEO, Midsummer. “Our unique process makes thin film CIGS solar cells even more commercially attractive by making it possible to manufacture solar cells fast, efficiently and cost effectively even in small volumes.”