Advanced technology for the production of thin film solar photovoltaic panels

Thin film photovoltaic cells to be produced in a safer, faster and cheaper manner by using continuous flow microreactors, which are special nanostructure films where chemical reactions take place.

These are the objectives of a new technique that is being developed by researchers from the Oregon State University and the Yeungnam University (South Korea), reported by the journal Current Applied Physics.

Chemical bath deposition is a technique that has been developed in the past due to its relatively low cost, but is very slow and includes difficulties connected with the control of the process and the fast depletion of reagents.

These issues have apparently been overcome by nanostructured continuous flow microreactors, that create a more commercially practical and less expensive process which the Oregon university is patenting.

The material used for photovoltaic conversion is another innovation, a semiconductor known as CIGS (Copper Indium Gallium Selenide). This material has already been widely tested as an alternative to silicon for photovoltaic applications, but with deposition methods (sputtering, evaporation or electrodeposition) that are slow and expensive. These difficulties are expected to be overcome by using microreactors.

"We have demonstrated for the first time that this system can produce thin film cells on a glass substrate in a short time," said Chih-Hung Chang, a professor of the School of Chemical, Biological and Environmental Engineering at the Oregon State University.

One of the most interesting applications of these new approaches regards photovoltaic panels for roofing systems on buildings: instead of being added on top of the roof, the panels themselves would become the roof, so that the traditional layers of insulating material would no longer be needed.