METHOD FOR MANUFACTURING HIGH-PURITY ERBIUM, HIGH-PURITY ERBIUM, SPUTTERING TARGET COMPOSED OF HIGH-PURITY ERBIUM, AND METAL GATE FILM HAVING HIGH-PURITY ERBIUM AS MAIN COMPONENT

摘要

Provided is a method for manufacturing a high-purity erbium, wherein a crude erbium oxide is mixed with a reduced metal, erbium is reduced and distilled by heating the mixed material in vacuum, the reduced and distilled erbium is molten in an inert atmosphere and a high-purity erbium is obtained. A high-purity erbium which has a purity of 4N or more, excluding rare-earth elements and gas components, and contains 200 wtppm or less of oxygen is also provided. Furthermore, a method for highly purifying erbium, which is difficult to be purified in the metal's molten state with high vapor pressure, a high-purity erbium obtained by such method, a sputtering target composed of a high-purity material erbium, and a technology of efficiently and stably providing a metal gate thin film having a high-purity material erbium as the main component are also provided.