An object of the invention is to provide a coated cutting tool whose tool life can be extended by having excellent wear resistance and fracture resistance. The coated cutting tool includes: a substrate; and a coating layer formed on a surface of the substrate, in which the coating layer includes a lower layer, an intermediate layer, and an upper layer in this order from a substrate side to a surface side of the coating layer, the lower layer includes one or more Ti compound layers formed of a specific Ti compound, the intermediate layer contains TiCNO, TiCO, or TiAlCNO, the upper layer contains α-type Al.sub.2O.sub.3, an average thickness of the lower layer is 2.0 μm or more and 8.0 μm or less, an average thickness of the intermediate layer is 0.5 μm or more and 2.0 μm or less and is 10% or more and 20% or less of an average thickness of the entire coating layer, an average thickness of the upper layer is 0.8 μm or more and 6.0 μm or less, and in the intermediate layer, a ratio of a length of CSL grain boundaries and a ratio of a length of Σ3 grain boundaries are in specific ranges.

An object of the invention is to provide a coated cutting tool whose tool life can be extended by having excellent wear resistance and fracture resistance. The coated cutting tool includes: a substrate; and a coating layer formed on a surface of the substrate, in which the coating layer includes a lower layer, an intermediate layer, and an upper layer in this order from a substrate side to a surface side of the coating layer, the lower layer includes one or more Ti compound layers formed of a specific Ti compound, the intermediate layer contains TiCNO, TiCO, or TiAlCNO, the upper layer contains α-type Al.sub.2O.sub.3, an average thickness of the lower layer is 2.0 μm or more and 8.0 μm or less, an average thickness of the intermediate layer is 0.5 μm or more and 2.0 μm or less and is 10% or more and 20% or less of an average thickness of the entire coating layer, an average thickness of the upper layer is 0.8 μm or more and 6.0 μm or less, and in the intermediate layer, a ratio of a length of CSL grain boundaries and a ratio of a length of Σ3 grain boundaries are in specific ranges.

PECVD methods for depositing a film at a low deposition rate comprising intermittent activation of the plasma are disclosed. The flowable film can be deposited using at least a polysilane precursor and a plasma gas. The deposition rate of the disclosed processes may be less than 500 Å/min.

The present invention relates to a component for manufacturing a semiconductor manufactured by using a CVD method. A SiC structure formed by the CVD method according to one aspect of the present invention is used such that the SiC structure is exposed to plasma inside a chamber, wherein the SiC structure comprises a crystal grain structure in which the length in a first direction is longer than the length in a second direction when defining a direction perpendicular to the surface most exposed to the plasma as the first direction and a direction horizontal to the surface most exposed to the plasma as the second direction.

Methods and systems for forming a structure including a silicon carbide layer and structures formed using the methods and systems are disclosed. Exemplary methods include providing a silicon carbide precursor to the reaction chamber, forming a plasma within the reaction chamber to form an initially flowable, viscous silicon carbide material on a surface of the substrate, wherein the initially viscous carbon material becomes the silicon carbide layer. Exemplary methods can include use of a silicon carbide precursor that includes a carbon-carbon triple bond and/or use of a relatively low plasma power density (e.g., less than 3 W/cm.sup.2).

A member for an apparatus for manufacturing a semiconductor single crystal having long product life and a tantalum carbide coated carbon material are provided. The tantalum carbide coated carbon material according to the present invention is a tantalum carbide coated carbon material in which at least a part of a surface of a carbon base material is coated with a tantalum carbide coated film containing tantalum carbide as a main component, in which in the tantalum carbide coated film, an intensity of an X-ray diffraction line corresponding to a plane with respect to an out-of-plane direction is larger than intensities of X-ray diffraction lines corresponding to other crystal planes, and the intensity ratio is 60% or more with respect to a sum of intensities of X-ray diffraction lines corresponding to all crystal planes.

A member for an apparatus for manufacturing a semiconductor single crystal having long product life and a tantalum carbide coated carbon material are provided. The tantalum carbide coated carbon material according to the present invention is a tantalum carbide coated carbon material in which at least a part of a surface of a carbon base material is coated with a tantalum carbide coated film containing tantalum carbide as a main component, in which in the tantalum carbide coated film, an intensity of an X-ray diffraction line corresponding to a plane with respect to an out-of-plane direction is larger than intensities of X-ray diffraction lines corresponding to other crystal planes, and the intensity ratio is 60% or more with respect to a sum of intensities of X-ray diffraction lines corresponding to all crystal planes.

A SiC epitaxial wafer includes a SiC substrate and an epitaxial layer laminated on the SiC substrate, wherein the epitaxial layer contains an impurity element which determines the conductivity type of the epitaxial layer and boron which has a conductivity type different from the conductivity type of the impurity element, and the concentration of boron is less than 1.0×10.sup.14 cm.sup.−3 at any position in the plane of the epitaxial layer.

The disclosure relates to a device for continuously producing qualitatively high-grade crystalline silicon carbide, in particular in the form of nanocrystalline fibre.

Provided is a SiC-coated carbon composite material including a graphite base material and a CVD-SiC coating covering the graphite base material. A porosity of a core part of the graphite base material is 12 to 20%, and a SiC-infiltrated layer extending from the CVD-SiC coating is included in a periphery of the core part of the graphite base material. The SiC-infiltrated layer is constituted of a plurality of regions arranged such that Si content becomes smaller stepwise in an order from a first surface on the CVD-SiC coating side toward a second surface on the graphite base material side.