Abstract: A body coated with cubic boron nitride comprises: a base material; a first interlayer of nitride or boride with which at least one element of IVb group, IIIb group, Vb group, IVa group, Va group and VIa group of the periodic table, in accordance with the quality of the material of the base material is mixed, and the composition ratio of the at least one element is decreased towards the surface, the first interlayer being formed on the base material; and/or a second interlayer of nitride or boride with which at least one element of IVb group, IIIb group, Vb group, IVa group, Va group and VIa group of the periodic table, in accordance with the quality of the material of the base material is mixed at the total mixing amount 0.01 atomic % to 10 atomic %, and shows an absorption peak at the wave number of 950 cm.sup.-1 to 1150 cm.sup.

Abstract: A wafer, in which at least one via hole is made in an insulating film formed on the substrate, is held on a wafer holder in a reaction chamber under reduced pressure, WF.sub.6 gas is introduced into the reaction chamber so that a first metallic film of W is formed on the substrate in the via hole. The additional WF.sub.6 gas and H.sub.2 gas are introduced into the chamber and light from a heating lamp is directed onto the wafer such that a difference in temperature is created between the insulating film and the first metallic film such that a second metallic film of W is formed only on the first metallic film. The temperature difference is created because of the differences of the absorption ratios of infrared components of the light between the insulating film, the substrate and the first metallic film. The WF.sub.6 gas and H.sub.