HIGH-PURITY YTTRIUM, PROCESS OF PRODUCING HIGH-PURITY YTTRIUM, HIGH-PURITY YTTRIUM SPUTTERING TARG

Provided are high-purity yttrium and a high-purity yttrium sputtering target each having a purity, excluding rare earth elements and gas components, of 5 N or more and containing 1 wt ppm or less of each of Al, Fe, and Cu; a method of producing high-purity yttrium by molten salt electrolysis of a raw material being a crude yttrium oxide having a purity, excluding gas components, of 4N or less at a bath temperature of 500°C to 800°C to obtain yttrium crystals, desalting treatment, water washing, and drying of the yttrium crystals, and then electron beam melting for removing volatile materials to achieve a purity, excluding rare earth elements and gas components, of 5N or more; and a technology capable of efficiently and stably providing high- purity yttrium, a sputtering target composed of the high-purity yttrium, and a metal- gate thin film mainly composed of the high-purity yttrium.