In this paper, a review of the present status of the research and technological development in the field of superhard nanocomposite coatings is attempted. Various deposition techniques have been used to prepare nanocomposite coatings. Among them, reactive magnetron sputtering is most commonly used. Nanocomposite coating design methodology and synthesis are described with emphasis on the magnetron sputtering deposition technique. Also discussed are the hardness and fracture toughness measurements of the coatings and the size effect. Superhard nanocomposite thin films are obtainable through optimal design of microstructure. So far, much attention is paid to increasing hardness, but not enough to toughness. The development of next generation superhard coatings should base on appropriate material design to achieve high hardness and at the same time high toughness.

Recent advances of superhard nanocomposite coatings: a review

Magnetron sputtering of films with controlled texture and grain size

PROBLEM TO BE SOLVED: To provide a hard coating for a cutting tool superior to a TiAlN film in abrasion resistance. SOLUTION: The hard coating is constituted by a compound expressed by (Al b , [Cr 1-α V α ] c ) (C 1-d N d ), where the symbols satisfy 0.5≤b≤0.8, 0.2≤c≤0.5, b+c=1, 0.05≤α≤0.95, and 0.5≤d≤1. Alternatively, the hard coating is constituted by a compound expressed by (M a , Al b , [Cr 1-α V α ] c ) (C 1-d N d ), where M is at least one selected from the group consisting of Ti, Nb, W, Ta and Mo, and other symbols satisfy 0.02≤a≤0.3, 0.5≤b≤0.8, 0.05≤c, a+b+c=1, 0.5≤d≤1, and 0≤α≤1 ((a) indicates an atomic ratio of M). However, M and α shall no be simultaneously Ti and zero respectively. COPYRIGHT: (C)2003,JPO

Hard coating for cutting tool, manufacturing method therefor and target for forming hard coating

A hard film for cutting tools which is composed of (Ti1-a-b-c-d, Al a, Cr b, Si c, B d) (C l-e N e) 0.5 <= a <= 0.8, 0.06 <= b, 0 <<= c <= 0.1, 0 <= d <= 0.1, 0 <= c+d <= 0.1, a+b+c+d < 1, 0.5 <= e <= 1 (where a, b, c, and d denote respectively the atomic ratios of Al, Cr, Si, and B, and a denotes the atomic ratio of N).

Hard film for cutting tools, cutting tool coated with hard film, process for forming hard film, and target used to form hard film

Disclosed are a thin film transistor substrate where barrier metal can be omitted to be formed between a semiconductor layer of a thin film transistor and source and drain electrodes (barrier metal need not be formed between the semiconductor layer of the thin film transistor and the source and drain electrodes), and a display device. (1) A thin film transistor substrate has a semiconductor layer of a thin film transistor, a source electrode, a drain electrode, and a transparent conductive film, wherein the substrate has a structure in which the source and drain electrodes are directly connected to the semiconductor layer of the thin film transistor, and the source and drain electrodes include an Al alloy thin film containing Ni of 0.1 to 6.0 atomic percent, La of 0.1 to 1.0 atomic percent, and Si of 0.1 to 1.5 atomic percent. (2) A display device has the thin film transistor substrate.

Thin film transistor substrate and display device

A study of hillock formation on AlTa alloy films for interconnections of TFT-LCDs

Effects of adding group VIII transition metals (Fe, Co, and Ni) to an aluminum target on electrical resistivity and hillock suppression of sputter‐deposited Al alloy films were studied. It was found that the group VIII transition metals and Al formed a complete series of metastable solid solutions in the as‐deposited state. The solid solutions were decomposed into intermetallic compounds, and the microstructures of the Al alloy films changed during annealing up to 300 °C. The electrical resistivities of Al–Fe, Al–Co, and Al–Ni alloy films changed corresponding to the change in their microstructures, and markedly decreased to 5.0 μΩ cm at the precipitation points. The film stresses also changed corresponding to the change in the microstructure of the Al alloy films, and were abruptly relieved by precipitation of intermetallic compounds and grain growth. Since Al–Fe, Al–Co, and Al–Ni alloy films did not yield, they are highly resistant to hillock formation. The low electrical resistivity and the excellent resistance to hillock formation of Al–group VIII transition metal alloy films were explained on the basis of microstructural changes before and after annealing.

Influence of adding transition metal elements to an aluminum target on electrical resistivity and hillock resistance in sputter‐deposited aluminum alloy thin films

Disclosed is an electrode for semiconductor devices capable of suppressing the generation of hillocks and reducing the resistivity, which is suitable for an active matrixed liquid crystal display and the like in which a thin film transistor is used; its fabrication method; and a sputtering target for forming the electrode film for semiconductor devices. The electrode for semiconductor devices is made of an Al alloy containing the one or more alloying elements selected from Fe, Co, Ni, Ru, Rh and Ir, in a total amount from 0.1 to 10 At %, or one or more alloying elements selected from rare earth elements, in a total amount from 0.05 to 15 at %. The method of fabricating an electrode for semiconductor devices, includes the steps of: depositing an Al alloy film, in which the elements mentioned above are dissolved in an Al matrix, on a substrate; and precipitating part of all of the elements dissolved in the Al matrix as intermetallic compounds by annealing the Al alloy film at an annealing temperature ranging from 150 to 400° C.; whereby an electrode for semiconductor devices which is made of an Al alloy film with an electrical resistivity lower than 20 μΩcm is obtained. The target is made of an Al alloy containing the above elements.

Electrode and its fabrication method for semiconductor devices, and sputtering target for forming electrode film for semiconductor devices

An Al alloy film containing one kind or two or more kinds of alloy components selected from a group of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and Mn in a total amount of 0.1 to 10 at %, and a melting Al alloy sputtering target for depositing the Al alloy film, wherein the above-mentioned film is used as a reflection film for an optical recording medium, a shading film for a liquid crystal display panel or for a solid image pickup device, and an Al alloy thin film line or electrode material for a semiconductor device.

A1 alloy films and melting A1 alloy sputtering targets for depositing A1 alloy films

PROBLEM TO BE SOLVED: To provide a mesh member for screen printing in which photosensitive emulsion in a part equivalent to an area in which printing is not made even if printing is repeated, cannot be easily exfoliated from the rolling metal foil, about the mesh member for screen printing which includes the rolling metal foil which is good in dischargeability of paste in a part equivalent to the printing area.SOLUTION: In the mesh member for screen printing for forming printing patterns by photosensitive emulsion, the mesh member includes rolling metal foil. The rolling metal foil includes the part equivalent to a printing area of the printing object, and the part equivalent to a non-printing area of the printing object. The open area rate of holes prepared in the part equivalent to the non-printing area is smaller than the open area rate of the holes prepared in the part equivalent to the printing area. The opening width of at least part of the holes prepared in the part equivalent to the non-printing area is constituted to become larger than the opening width of the hole prepared in the part equivalent to the printing area.

Kazuo Yoshikawa

Papers

A study of hillock formation on AlTa alloy films for interconnections of TFT-LCDs

Influence of adding transition metal elements to an aluminum target on electrical resistivity and hillock resistance in sputter‐deposited aluminum alloy thin films

Electrode and its fabrication method for semiconductor devices, and sputtering target for forming electrode film for semiconductor devices

A1 alloy films and melting A1 alloy sputtering targets for depositing A1 alloy films

Mesh member for screen printing