Progress in Chalcopyrite Compound Semiconductor Research for Photovoltaic Applications and Transfer of Results into Actual Solar Cell Production

Since the invention of the transistor in the late 1940's the search for new semiconductor materials has seen a continuous rising interest and the systematic search has been expanded to a wide range of compound materials. Already in the first half of the 1950's I-II-VI2 components were researched and the first II-VI-V2 compounds were synthesised. The invention of the CuInSe2/CdS solar cell in the early 1970's at Bell Labs spurred an increased research activity to use chalcopyrite compound semiconductors as base material for solar cells. So far the copper indium gallium sulphur selenide material family is the base for the highest efficiency thin film solar cells and the most advanced in terms of actual commercialisation. These solar cells are currently in the industrialisation phase with best commercial module efficiencies of up to 13.1% for CuInGaSe2 and 8.6% for CuInS2.JRC.DDG.F.8-Renewable Energy (Ispra