"Tandem solar cells, in which two solar cells with different absorption characteristics are linked to use a wider range of the solar spectrum, were fabricated with each layer processed from solution with the use of bulk heterojunction materials comprising semiconducting polymers and fullerene derivatives," wrote the authors.
...Heeger shared the Nobel Prize in Chemistry in the year 2000, with Alan MacDiarmid and Hideki Shirakawa, for the "discovery and development of conducting polymers." The tandem solar cells reported in the Science article utilize semiconducting polymers from the class of materials that were recognized by the award of the Nobel Prize.
With Howard Berke, Heeger in 2000 co-founded Konarka Technologies, based in Lowell, Mass., to develop and market solar cells based on this technology
From the University of California, Santa Barbara
Konarka Named to “Ten to Watch” List of Companies in Newly Released Book, The Clean Tech Revolution