Abstract: Disclosed is a method of chemically-mechanically polishing a substrate. The method comprises, consists of, or consists essentially of (a) contacting a substrate containing a low-k dielectric composition, which includes less than about 80% by weight of carbon, with a polishing pad and a chemical-mechanical polishing composition comprising water and abrasive particles having a positive surface charge, wherein the polishing composition has a pH of from about 3 to about 6; (b) moving the polishing pad and the chemical-mechanical polishing composition relative to the substrate; and (c) abrading at least a portion of the substrate to polish the substrate. In some embodiments, the low-k dielectric composition is carbon-doped silicon oxide.