We have developed a novel technique to grow device-grade Cu(In,Ga)Se₂ (CIGS) thin films using a radio frequency cracked Se-radical beam source. A Se-radical source meets the technical challenges of high-quality CIGS film growth, efficient use of Se source, and precise control of growth conditions and film properties. Using a CIGS absorber grown with a Se-radical source, an energy conversion efficiency of 17.5 %, which is comparable to conventional CIGS solar cell performance, has been achieved. Se source material consumption by the Se-radical source is significantly reduced to be less than 1/10 compared with a conventional Se-evaporative source. This result will lead to reduced production costs of CIGS solar cell modules and sharply reduced levels of industrial waste generation.