摘要 |
A process for producing a high-purity Mn material comprising the steps of premelting crude Mn at 1250-1500° C. and vacuum distilling the melt at 1100-1500° C. The degree of vacuum during the vacuum distillation ranges from 5x10-6 torr to 10 torrs. A crucible for use in the vacuum distillation is a double crucible, which consists of inner and outer crucibles, and a carbon felt packed in the space therebetween. A high-purity Mn material for thin film deposition which contains a total of not more than 100 ppm impurity metallic elements, not more than 200 ppm oxygen, not more than 50 ppm nitrogen, not more than 50 ppm S, and not more than 100 ppm C.
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