METHOD OF REMOVING POLYMER RESIDUES AFTER TUNGSTEN ETCH BACK

摘要

The invention describes a method for lowering particle count after tungsten etch back, in which method a plasma ashing step is performed after a brush cleaning step to eliminate polymer residues that remain on the metal barrier layer after tungsten etch back. Another tungsten etch back process is further performed to remove a tungsten oxide film that is formed by reacting the tungsten layer with an O2 gas used in the plasma ashing step.