Abstract: The present invention relates to high purity chromium metal suitable for deposition onto a semiconductor wafer or other substrate by sputtering. The high purity chromium metal is produced by a process that increases productivity, expands melting capability and provides consistent high purity chromium by reducing contamination by the dissolution of crucible material. The present invention provides high purity chromium by the addition of chromium oxide (Cr.sub.2 O.sub.3) to molten chromium to control oxygen content in the chromium thereby producing high purity chromium ingots and protecting the ceramic crucibles from chemical attach by the liquid chromium.
Type:
Grant
Filed:
March 24, 1997
Date of Patent:
February 2, 1999
Assignee:
Sony Corporation and Materials Research Corporation
Inventors:
Raymond K. F. Lam, Charles E. Melin, Guiseppe Colella