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In recent years, multielement films have been required for high-performance cutting tools. In this paper, a Y-shaped filtered-arc-deposition (Y-FAD) system with two vacuum-arc sources was developed. First, an optimum magnetic coil arrangement was experimentally established to transport two plasma beams through the Y-shaped duct at the same time. Since the two plasma beams have the same electrical polarity, they naturally tend to repel each other. Therefore, in the second step, the two plasma beams were combined into one plasma beam through a mixer part by vibrating the plasma beams with a laterally oscillating magnetic field. Third, the electrical bias applied to the duct was optimized to obtain a higher transportation rate of plasma and deposition rate. After these design developments and tuning, titanium-aluminum (Ti-Al) film with a combined deposition pattern was finally obtained with Al and Ti cathodes. The controllability of the composition ratio by the arc current was verified.

A Y-shape filtered-arc-deposition system, which has two arc sources and a common plasma-transport-duct, was operated under nitrogen gas, and a titanium aluminum nitride (TiAlN) thin film was prepared with Ti and Al cathodes. Two filtered-arc plasma beams were not completely combined into one beam even at the exit of the common duct. Thus, TiAlN film with composition-uniform distribution was not obtained at the fixed substrate position. However, different composition films were easily obtained at one time. Then various-composition films of TiAlN with different arc currents were prepared and film properties were measured. The surface roughness in arithmetical mean roughness was less than 3 nm on a 1.5-nm roughness substrate. The density of TiAlN increased with the Ti-content ratio, and its hardness tended to weakly increase with Al-content ratio. The maximum hardness was 36 GPa. Ti-rich film has internal compression stress and Al-rich film has internal tensile stress.