Composition for polishing and method for polishing a semiconductor substrate using the same

Provided is a polishing composition containing abrasive grains, at least one kind of an alcohol compound, selected from the group consisting of aliphatic alcohols having from 2 to 6 carbon atoms and glycol ethers having 3 to 10 carbon atoms, at least one kind of a basic compound selected from the group consisting of quaternary ammonium salts and alkali metal salts, and water. The average particle diameter of the abrasive grains is 5 to 50 nm. The content of the alcohol compound in the polishing composition is from 5 to 50 nm. The polishing composition is used mainly in polishing a semiconductor substrate surface.