Patent attributes
A method for forming a multi-layer, hard coating on a substrate, said hard coating comprising at least one metal element selected from the group consisting of transition metal elements of Groups 4a, 5a and 6a in the Periodic Table, Al, Si and B (at least one of said transition metal elements is indispensable), and at least one non-metal element selected from the group consisting of S, O, N and C (S is indispensable), and having a columnar structure comprising columnar crystal grains having pluralities of layers having different S contents, said method comprising placing said substrate in a chamber comprising evaporation sources having different plasma densities and a reaction gas for physical vapor deposition, and alternately bringing said substrate closer to each evaporation source, while keeping said reaction gas in a plasma state and said evaporation sources simultaneously in an active state.