Patent ID: 8901002
Filing Date: 2014-12-02
Classification: C09G,C23F,H01L

Abstract:
1. A polishing method, characterized by including: a step of preparing a substrate having an interlayer dielectric having a surface comprising concave regions and convex regions, a barrier layer for covering the interlayer dielectric along the surface thereof, and an electroconductive material layer filled into the concave regions so as to cover the barrier layer; a first polishing step of polishing the electroconductive material layer of the substrate, thereby making the barrier layer over the convex regions exposed; and a second polishing step of exposing the interlayer dielectric over the convex regions by polishing the barrier layer exposed in the first polishing step by using a polishing slurry for metal films, the second polishing step comprising an over-polishing step of polishing the interlayer dielectric, wherein the polishing slurry for metal films comprises abrasive grains, an oxidized metal dissolving agent, a methacrylic acid based polymer, an organic solvent and water, the methacrylic acid based polymer is at least one selected from the group consisting of a copolymer having a ratio of the amount of methacrylic acid to the total amount of the monomers being 70% or more and less than 100% by mole and a homopolymer made from a methacrylic acid, the oxidized metal dissolving agent is at least one selected from organic acids, esters of organic acid and ammonium salts of organic acid, the blend amount of the methacrylic acid based polymer is from 0.001 to 15 g for 100 g of the total amount of all components of the polishing slurry for metal films, the organic solvent is at least one selected from glycol monoethers, ethers and alcohols, and the weight-average molecular weight of the methacrylic acid based polymer is 3000 or more and 1000000 or less.