Contacts and interfaces for high efficiency solar cells

Time period: 2017-10-01 to 2020-09-30

Project leader: Tobias Törndahl

Funder: Swedish Energy Agency

Type of award: Project grant

Total fundning: 5 956 200 SEK

The proposed project, within the call “El från solen”, will support the ongoing energy transition towards sustainable sources in society today by strengthening the position of Cu(In,Ga)Se2 (CIGS) and Cu2ZnSn(S,Se)4 (CZTS) thin film solar cells by increasing the conversion efficiency, improve the long term stability and lower the production costs. The aim is to increase the efficiency by improving the quality of the important pn-junction, situated between CIGS/CZTS and the so called buffer layer. The buffer layer of choice today is CdS grown by wet chemical processing. However, cadmium is classified as toxic and the CdS layer absorbs some of the incoming sun light. In the proposed project, Atomic layer deposition will be used to synthesize new buffer layers with improved material properties, and the interface between CIGS/CZTS buffer will be studied by different analysis techniques. The new considered buffer materials in this project are oxides containing Sn, Ga, Ge, and Zn.