PURPOSE: To obtain a BN-contg. film coated substrate having high hardness and high toughness and excellent in stability and adhesion by laminating an inner film in which the ratio of B to N is relatively high, an outer film in which the ratio of B to N is low and a middle film in which the ratio of B to N is medium on a substrate.
CONSTITUTION: The top of a substrate S is coated with an inner film S1, an outer film S3 and one or more middle films S2 as plural BN-contg. films S10 to obtain the objective BN-contg. film coated substrate. The ratio of B to N in the inner film S1 is 4-70 and the film S1 has an IR absorption peak of its IR absorption spectrum at 1,080cm-1 or a lower peak at 1,380cm-1 and a higher peak at 1,080cm-1. The ratio of B to N in the outer film S3 is ≤3 and the film S3 has IR absorption peaks at 1,380cm-1 and 780cm-1. The ratio of B to N in the middle films S2 is between the ratio of B to N in the inner film S1 and that in the outer film S3 and the films S2 have IR absorption peaks at 1,380cm-1 and 1,080cm-1.
IWAMOTO YASUSHI
EBE AKINORI
OGATA KIYOSHI
