HIGH-PURITY LANTHANUM, METHOD FOR PRODUCING SAME, SPUTTERING TARGET COMPRISING HIGH-PURITY LANTHANUM, AND METAL GATE FILM COMPRISING HIGH-PURITY LANTHANUM AS MAIN COMPONENT

摘要

High-purity lanthanum characterized in that the purity, in terms of the purity of the lanthanum excluding any rare-earth elements and any gas components, is 5 N or higher and the number of α-ray counts is 0.001 cph/cm