Saint-Gobain subsidiary, AVANCIS has reported a 30 x 30 cm² champion CIS thin-film module with a conversion efficiency of 16.6%, verified by the National Renewable Energy Laboratory (NREL).

The thin-film manufacturer claimed the verified efficiency of an encapsulated CIS module was a new record, surpassing its last externally certified efficiency record in 2011. According to previous data from IMS Research in late 2011, AVANCIS was offering commercial CIS modules (‘PowerMax’) with conversion efficiencies of 12.6%, equal at the time to module efficiencies of current CIS market leader by capacity and shipments, Solar Frontier.

Dr. Jörg Palm, Head of Process Development at AVANCIS said, “The increased efficiency shows the enormous potential of our CIS production process. “A transfer of the pilot process to the production would lead to an impressive module performance of nearly 160Wp of the approximately 1 m² sized PowerMax modules. The very good homogeneity of the CIS absorber properties based on production dimensions of 158 x 66 cm² were demonstrated by the minor deviation of 0.15 % absolute between different 30 x 30 cm² modules from the same full-size absorber."

The company highlighted that the conversion efficiency gains were driven by the optimization of the buffer layer through enhancements to the ‘InxSy’ bandgap, band matching, and transmission in a short wavelength range.

Transmittance and the sheet resistance of the sputtered ZnO:Al front contact was also said to have been optimized and the dead zone between the series-connected cells was reduced by employing a picosecond laser process.

The company did not say whether the results could be transferred to commercial production, though the absorber layer used commercial processes and the buffer layer was processed at its R&D facility in Munich.

