Melting and casting of high purity chromium with controlled oxygen content

摘要

The present invention relates to a method of manufacturing high purity chromium suitable for deposition onto a semiconductor wafer or other substrate by sputtering. The process increases productivity, expands melting capability and provides consistent high purity chromium by reducing contamination by the dissolution of crucible material. The present invention provides for the addition of chromium oxide (Cr2O3) to control oxygen content in chromium thereby producing high purity chromium ingots and protecting the ceramic crucibles from chemical attack by the liquid chromium.