CMP SLURRY COMPOSITION FOR TUNGSTEN

摘要

PURPOSE: A slurry composition for chemical mechanical polishing is provided to prevent the slurry discoloration problem, to have excellent etching selection ratio between metallic layers and to be applied to a chemical mechanical polishing process. CONSTITUTION: A slurry composition for chemical mechanical polishing comprises an abrasive and an abrasive accelerator. The abrasive comprises colloid silica which is dispersed in ultrapure water. The abrasive accelerator comprises 0.5-2 weight% hydrogen peroxide liquid, 0.05-1 weight% of ammonium persulfate, 0.01-0.1 weight% of iron nitrate. The content of the colloid silica is 2-4 weight%. The etching selection ratio of the tungsten and nitride titanium is 1:1.5-2. The pH of the composition is 2-4.