Method of manufacturing semiconductor device

摘要

A first insulating film, a first wiring layer and a second insulating film are successively formed over a semiconductor substrate. A resist mask is patterned over the second insulating film, and isotropic etching and anisotropic etching are successively carried out to define a plurality of via holes within the second insulating film. The via holes thus have a first portion formed by the isotropic etching and a second portion formed by the anisotropic etching. The resist mask is removed, and a high melting-point metal film is formed over the second insulating film so as to be embedded in the plurality of via holes. The high melting-point metal film and the second insulating film are then polished down to the first portion of each of the via holes such that respective portions of the high melting-point metal film formed within adjacent ones of the plurality of via holes are isolated from each other. A second wiring layer is then formed so as to be electrically connected to the first wiring layer through the portions of the high melting-point metal film formed within the plurality of via holes.