PURPOSE: To form a high melting point metallic layer without polluting a semiconductor device while cleaning up the substrate surface after ion-implantation using a chemical as well as a wafer before forming a high melting point metal as a wiring layer by a method wherein ion is implanted above the thin metal in high melting point and chemical resistance formed on a titanium nitride layer of the semiconductor device.

CONSTITUTION: After forming a titanium nitride 4 on a silicon substrate 1 through the intermediary of an insulating film 2, a thin tungsten layer 5 is formed in the clean state of a wafer before it is implanted with an impurity. Next, the impurity concentration on the interface between the substrate 1 and the titanium layer 4 is increased to ion-implant the impurity 6 for destroying the insulating silicon oxide film on the substrate 1. At this time, the high melting point tungsten layer 5 completely covers the titanium layer 4 to facilitate the ion-implantation. Later, the transition metal, organic substance, etc., adhered to the surface in the ion implanting process are removed by surface cleaning process and then another thick tungsten layer 7 is formed as an insulating layer to be simultaneously patterned into a wiring layer.