Manufacturing method of semiconductor integrated circuit device that includes chemically and mechanically polishing two conductive layers using two polishing pads that have different properties

Abstract

In the forming process of buried wirings by filling wiring trenches formed in an insulator with a conductive film mainly made of Cu, the buried wirings are formed to have a uniform-height regardless of the width and density of the wiring trenches. When polishing a barrier conductor film comprised of a Ta film in the CMP process for forming the buried wirings, the polishing agent, which controls the removal rate of the underlying insulator of a silicon oxide film relative to the barrier conductor film to almost one twentieth or less, is used as the slurry, and the pad which is made of polyurethane with a hardness of 75 degrees or more measured by the Type E durometer in conformity with the JIS K6253 and which is comprised of the foam including non-uniform pores with a diameter of about 150 μm or larger and a density of about 0.4–0.16 g/cm, is used as the polishing pad.