TWI772171B

Disclosed is a protective film for a chemical mechanical polishing pad dresser, wherein the dresser at least comprises a stainless-steel base material, a nickel layer and a plurality of diamond particles. The nickel layer covers the surface of the stainless-steel base material. Each diamond particle is distributed on the stainless-steel base material in a manner that a portion of the diamond particle is embedded in the nickel layer and the remaining portion is exposed outside the nickel layer. The protective film only covers the surface of the nickel layer and exposes the surface of the diamond particles to prevent a polishing slurry from corroding the nickel layer. The protective film is formed by plasma polymerization and deposition of hexamethyldisilazane or hexamethyldisiloxane. The thickness of the protective film is in a range of 0.5-3 [mu]m.