A chemical vapor infiltration (CVI) method for densifying at least one porous component includes placing the at least one porous component inside a crucible, bringing temperature inside the crucible to a value adapted to densify the porous component to transform it into a densified component, bringing pressure inside the crucible between 0.1 KPa and 25 KPa, once operational temperature and pressure are reached, flowing gas inside the crucible, gas being suitable for densifying the porous component to transform it into a densified component, and keeping an oxidizing environment outside the crucible, the external environment lapping against the crucible. The crucible is provided of at least one material having thermal conductivity greater than 30 W/mK from room temperature to at least 1000° C. selected from: sintered silicon carbide (SiC), silicon-infiltrated silicon carbide (Si—SiC), sintered boron carbide (B4C), silicon-infiltrated boron carbide (Si—B4C), sintered zirconium carbide (ZrC), silicon-infiltrated zirconium carbide (Si—ZrC), a combination of silicon carbide (SiC), boron carbide (B4C) and sintered and/or silicon-infiltrated zirconium carbide (ZrC).

Color unevenness generated on a surface of a silicon nitride substrate is reduced. A silicon nitride substrate formed by nitriding silicon containing in a sheet-shaped green body includes a first surface and a second surface opposite to the first surface. In this case, when color difference between a center and an edge of at least one surface of the first surface and the second surface is expressed to be “ΔE*ab”, a relation “ΔE*ab≤1.5” is established.

The present invention relates to a method for preparing a SiC—Si.sub.3N.sub.4 composite material and a SiC—Si.sub.3N.sub.4 composite material prepared according to same and comprises the steps of: preparing a mold; and forming a SiC—Si.sub.3N.sub.4 composite material by introducing, to the mold, a source gas comprising Si, N and C, at 1100 to 1600° C. More particularly, the present invention provides the SiC—Si.sub.3N.sub.4 composite material of high purity that is applicable to a semiconductor process, and increases the thermal shock strength of a SiC material by causing Si.sub.3N.sub.4, which is a material with a high thermal shock strength, to grow together via a CVD method.

Disclosed is a composition having nanoparticles or particles of a refractory metal, a refractory metal hydride, a refractory metal carbide, a refractory metal nitride, or a refractory metal boride, an organic compound consisting of carbon and hydrogen, and a nitrogenous compound consisting of carbon, nitrogen, and hydrogen. The composition, optionally containing the nitrogenous compound, is milled, cured to form a thermoset, compacted into a geometric shape, and heated in a nitrogen atmosphere at a temperature that forms a nanoparticle composition comprising nanoparticles of metal nitride and optionally metal carbide. The nanoparticles have a uniform distribution of the nitride or carbide.

Systems for and methods of manufacturing a ceramic matrix composite include introducing a gaseous precursor into an inlet portion of a reaction furnace having a chamber comprising the inlet portion and an outlet portion that is downstream of the inlet portion, and delivering a mitigation agent, such as water vapor or ammonia, into an exhaust conduit in fluid communication with and downstream of the outlet portion of the reaction chamber so as to control chemical reactions occurring with the exhaust chamber. Introducing the gaseous precursor densifies a porous preform, and introducing the mitigation agent shifts the reaction equilibrium to disfavor the formation of harmful and/or pyrophoric byproduct deposits within the exhaust conduit.

A method of manufacturing a ceramic matrix composite component may include introducing a gaseous precursor into an inlet portion of a chamber that houses a porous preform and introducing a gaseous mitigation agent into an outlet portion of the chamber that is downstream of the inlet portion of the chamber. The gaseous precursor may include methyltrichlorosilane (MTS) and the gaseous mitigation agent may include hydrogen gas. The introduction of the gaseous precursor may result in densification of the porous preform(s) and the introduction of the gaseous mitigation agent may shift the reaction equilibrium to disfavor the formation of harmful and/or pyrophoric byproduct deposits, which can accumulate in an exhaust conduit 340 of the system.

A metal oxynitride thin film having a perovskite structure, in which the metal oxynitride thin film has a composition represented by a compositional formula A.sub.1+αBO.sub.x+αN.sub.y wherein α is larger than zero and 0.300 or less, x+α is larger than 2.450, and y is 0.300 or more and 0.700 or less, an AO structure having a layered structure parallel to a plane perpendicular to a c-axis of the perovskite structure and having a composition represented by a general formula AO, and the AO structure is bonded with the perovskite structure and incorporated in the perovskite structure.

A method of manufacturing a semiconductor device includes forming a preliminary lower electrode layer on a substrate, the preliminary lower electrode layer including a niobium oxide; converting at least a portion of the preliminary lower electrode layer to a first lower electrode layer comprising a niobium nitride by performing a nitridation process on the preliminary lower electrode layer; forming a dielectric layer on the first lower electrode layer; and forming an upper electrode on the dielectric layer.

Disclosed is a composition having nanoparticles or particles of a refractory metal, a refractory metal hydride, a refractory metal carbide, a refractory metal nitride, or a refractory metal boride, an organic compound consisting of carbon and hydrogen, and a nitrogenous compound consisting of carbon, nitrogen, and hydrogen. The composition, optionally containing the nitrogenous compound, is milled, cured to form a thermoset, compacted into a geometric shape, and heated in a nitrogen atmosphere at a temperature that forms a nanoparticle composition comprising nanoparticles of metal nitride and optionally metal carbide. The nanoparticles have a uniform distribution of the nitride or carbide.

Methods of producing silicon carbide, and other metal carbide materials. The method comprises reacting a carbon material (e.g., fibers, or nanoparticles, such as powder, platelet, foam, nanofiber, nanorod, nanotube, whisker, graphene (e.g., graphite), fullerene, or hydrocarbon) and a metal or metal oxide source material (e.g., in gaseous form) in a reaction chamber at an elevated temperature ranging up to approximately 2400° C. or more, depending on the particular metal or metal oxide, and the desired metal carbide being produced. A partial pressure of oxygen in the reaction chamber is maintained at less than approximately 1.01×10.sup.2 Pascal, and overall pressure is maintained at approximately 1 atm.