Semiconductor device manufacture method preventing dishing and erosion during chemical mechanical polishing

Abstract

A first insulating film is formed on an underlying substrate, the first insulating film being made of a first insulating material. A second insulating film is formed on the first insulating film, the second insulating film being made of a second insulating material different from the first insulating material. A trench is formed through the second and first insulating film, the trench reaching at least an intermediate depth of the first insulating film. A wiring layer made of a conductive material is deposited on the second insulating film, the wiring layer burying the trench. The wiring layer is polished to leave the wiring layer in the trench. The wiring layer and second insulating film are polished until the first insulating film is exposed. Irregularity such as dishing and erosion can be suppressed from being formed.

Dependencies are inferred from the claim text.