METHOD FOR PREPARING HIGH-PURITY AU POWDERS USING DRY METHOD

摘要

The present invention relates to a method for preparing high-purity Au powders by applying a dry method (plasma processing) so as to prepare an Au target which is used for a semiconductor. The present invention is characterized in that high-purity Au powders can be prepared through plasma processing in which an ingot applied to plasma is a spent waste target and in granular form. According to the present invention, it is possible to prepare high-purity Au powders in a short time through plasma without post-processing. Au powders are prepared by setting a chamber atmosphere of plasma equipment to a vacuum atmosphere; forming plasma and a melting pool by inputting a certain amount of a waste target and granules and then removing metal impurities having low melting point; removing remaining impurities by means of a reducing gas; and modifying the electrical power of plasma, the amount of plasma gas, and retention time, thereby producing highly pure Au powder.