| abstract |
Purity excluding rare earth elements and gas components is 5N or more, Al, Fe, Cu, Ta are each 1 wtppm or less, W is 10 wtppm or less, carbon is 150 wtppm or less, alkali metal and alkaline earth metal are each 1 wtppm or less, High-purity erbium in which the transition metal elements other than N are 10 wtppm or less in total, and U and Th that are radioactive elements are each 10 wtppb or less. A method for purifying erbium that has a high vapor pressure and is difficult to purify in a molten metal state, a sputtering target made of high purity erbium and a high purity material erbium, and a metal gate mainly composed of high purity erbium It is an object to provide a technique capable of providing a thin film efficiently and stably. |