PURPOSE: To improve reliability of a wiring excluding the angle of the upper part of a hole by performing dry etching over the entire surface after forming tungsten at the contact hole part in a semiconductor device where a multi-layer wiring is connected through the contact hole.

CONSTITUTION: A first-layer wiring 3 is formed on a silicon substrate 1 where transistors, etc., are formed. An insulation layer 4 is formed on it and a contact hole 5 for connecting wires is formed. Approximately 2/3 of the contact hole 5 is embedded a tungsten 6, dry etching is performed over the entire surface with the tungsten 6 as a mask, and the angle at the upper part of the contact hole 5 is eliminated. After forming a second-layer wiring 7 by the sputtering method, an insulation film 8 is formed over the entire surface. The angle of the upper part of the hole 5 is in taper shape, thus improving the coverage of wiring and protection film of the upper layer.