High-purity and ultra-high purity Copper Indium Selenium CIS (CuInSe2) materials are crucial components for the research, development, and production of advanced technologies which require optimum properties, performance, and quality.

Ternary chalcopyrite compounds which may act as an absorber in thin films solar cells are mainly CuGaSe2, the CuInS2, CuInSe2, and the CuAlSe2. Because of their large optical absorption coefficient, a thickness of 1.5-2 microns is sufficient to absorb the useful portion of the solar spectrum. The most promising appears to be the CuInSe2 material, an 18.8% efficiency is obtained by the solar cells based on this material. However, its low bandgap (1,04ev) limits the open-circuit voltage and thus the efficiency of the solar cell.