METHOD FOR MANUFACTURING HIGH-PURITY ERBIUM, HIGH-PURITY ERBIUM, SPUTTERING TARGET COMPOSED OF HIG

Provided are a method for manufacturing high-purity erbium, wherein crude erbium oxide is mixed with reducing metal, erbium is reduced and distilled by heating the mixture in a vacuum, and the distillate is melted in an inert atmosphere to obtain high-purity erbium; and high-purity erbium, wherein the purity excluding rare-earth elements and gas components is 4N or higher and the oxygen content is 200 wtppm or less. An object of this invention is to provide a method of highly purifying erbium, which has a high vapor pressure and is difficult to be refined in a molten metal state, as well as technology for efficiently and stably providing high-purity erbium obtained with the foregoing method, a sputtering target composed of high-purity erbium, and a metal gate film having high-purity erbium as a main component.