| abstract |
The present invention discloses tungsten chemical mechanical polishing (CMP) buff or barrier compositions and related methods and systems. The composition is an abrasive; Solid state or water soluble catalysts; Corrosion inhibitors for W of oligomers or polymers comprising ethyleneimine units, propyleneimine units, and combinations thereof; Chemical additives of polystyrene sulfonic acids or polyacrylic acids, their ammonium salts, potassium salts or sodium salts having molecular weights in the range of 1,000 to 2,000,000; menstruum; And acidic pH. The composition provides low dishing and low erosion levels in the polished substrate while at the same time providing a relatively high oxide removal rate, high barrier film removal rate and low W removal rate. |