PRODUCTION METHOD FOR HIGH-PURITY LANTHANUM, HIGH-PURITY LANTHANUM, SPUTTERING TARGET COMPOSED OF HIGH-PURITY LANTHANUM, AND METAL GATE FILM CONTAINING HIGH-PURITY LANTHANUM AS MAIN COMPONENT

摘要

greater than the purity excluding rare-earth elements and gas components other than lanthanum in the lanthanum fluoride 4N a raw material, and reduced by distillation to prepare a lanthanum-calcium more purity 4N, the electron beam melting method, excluding the rare earth elements and gas components other than lanthanum, characterized in that to remove the volatile materials and the production of high-purity lanthanum having a purity of 4N or more . A method for manufacturing a high-purity lanthanum, Al, Fe, wherein the process for producing a high-purity lanthanum, characterized in that at most 10 wtppm, respectively the Cu. The method of production of high-purity lanthanum, which is characterized in that the gas components in a total amount less than 1000 wtppm. High-purity lanthanum, and a thin film for metal gate mainly composed of high-purity lanthanum sputtering target comprising high-purity lanthanum, and efficient, and also a challenge to provide a technique capable of providing a stable.