HIGH PURITY ERBIUM SPUTTERING TARGET COMPRISING HIGH PURITY ERBIUM METAL GATE FILM HAVING HIGH PURITY ERBIUM AS MAIN COMPONENT THEREOF AND PRODUCTION METHOD FOR HIGH PURITY ERBIUM

摘要

High purity erbium having: a purity of at least 5N excluding rare earth elements and gas components; no more than 1 wt ppm each of Al Fe Cu and Ta; no more than 10 wt ppm of W; no more than 150 wt ppm of carbon; no more than 1 wt ppm each of alkali metals and alkali rare earth metals; no more than 10 wt ppm in total of other transition metal elements; and no more than 10 wt ppb each of the radioactive elements U and Th. The present invention addresses the problem of providing: a method for increasing the purity of erbium which has a high vapor pressure and is difficult to purify in a molten state; high purity erbium obtained by said method; and technology capable of efficiently and stably providing a sputtering target comprising high purity material erbium and a metal gate thin film having the high purity erbium as the main component.