disclosed herein are a cmp slurry composition with high - planarity and a cmp process for polishing a dielectric film using the same . more specifically , a cmp slurry composition with high - planarity includes a carbon compound having tens of thousands of carboxyl groups and having a molecular weight ranging from hundreds of thousands to millions , an abrasive , and water . a cmp process for polishing a dielectric film utilizes the disclosed slurry composition . the slurry composition enables complete and overall planarization of the dielectric film by polishing the part of the film having a higher step difference through cmp process . accordingly , the disclosed slurry composition is useful for the cmp process of all semiconductor devices including those having ultrafine patterns .