Basic Research Opportunities in Cu-Chalcopyrite Photovoltaics

A brief review is presented of fundamental research topics of primary importance to the development of improved solar cells based on chalcopyrite-structure materials. The opinions presented are a concensus opinion of the authors of the paper, with input from members of the chalcopyrite solar cells research community in the United States. Major topical areas identified included, in order ofimportance, are 1) development of an integrated predictive understanding of CIGS(S) materials and devices, 2) development of novel deposition techniques and characterization of the mechanisms of growth in existing and novel processes, 3) novel materials, especially with wide-energy gaps other than Cu-based chalcopyrites, 4) development of real-time material characterizations for process control,and 5) alternative front- and rear-contact materials. Although the five topics identified are quite broad, they do not include all topics of interest. Also discussed briefly are some other potential research areas not in the highest priority topics, in particular, areas identified as primarily 'engineering' rather than 'science'.