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.

A method for manufacturing an epitaxial wafer comprising a silicon carbide substrate and a silicon carbide voltage-blocking-layer, the method includes: epitaxially growing a buffer layer on the substrate, doping a main dopant for determining a conductivity type of the buffer layer and doping an auxiliary dopant for capturing minority carriers in the buffer layer at a doping concentration less than the doping concentration of the main dopant, so that the buffer layer enhances capturing and extinction of the minority carriers, the minority carriers flowing in a direction from the voltage-blocking-layer to the substrate, so that the buffer layer has a lower resistivity than the voltage-blocking-layer, and so that the buffer layer includes silicon carbide as a main component; and epitaxially growing the voltage-blocking-layer on the buffer layer.

Provided are methods and systems for providing silicon-containing films. The composition of the silicon-containing film can be controlled by the choice of the combination of precursors and the ratio of flow rates between the precursors. The silicon-containing films can be deposited on a substrate by flowing two different organo-silicon precursors to mix together in a reaction chamber. The organo-silicon precursors react with one or more radicals in a substantially low energy state to form the silicon-containing film. The one or more radicals can be formed in a remote plasma source.

Forming a protective coating ex situ in an atomic layer deposition process to coat one or more chamber components subsequently installed in a reaction chamber provides a number of benefits over more conventional coating methods such as in situ deposition of an undercoat. In certain cases the protective coating may have a particular composition such as aluminum oxide, aluminum fluoride, aluminum nitride, yttrium oxide, and/or yttrium fluoride. The protective coating may help reduce contamination on wafers processed using the coated chamber component. Further, the protective coating may act to stabilize the processing conditions within the reaction chamber, thereby achieving very stable/uniform processing results over the course of processing many batches of wafers, and minimizing radical loss. Also described are a number of techniques that may be used to restore the protective coating after the coated chamber component is used to process semiconductor wafers.

Disclosed is a coated ceramic fiber including a silicon carbide coating layer adjacent to the ceramic fiber and a silicon dioxide coating layer adjacent to the silicon carbide coating layer, wherein the silicon dioxide coating layer forms micro cracks after a crystal structure transformation. The coated ceramic fiber may be included in a composite material having a ceramic matrix.

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 system for coating ceramic fibers for use in manufacturing a ceramic matric composite (CMC) article includes a frame having a plurality of frame members arranged so as to create a void therebetween. At least one of frame members includes a hollow body and at least one perforated hole defined in the hollow body. Thus, the ceramic fibers are securable at respective ends of the frame and extend across the void. The frame also includes an inlet in fluid communication with the perforated hole(s) so as to allow a coating material to flow into and through the hollow body and out of the perforated hole(s) at a location of at least a portion of one of the ceramic fibers. As such, the coating material is configured to cause the portion of one of the ceramic fibers to separate from the frame such that the portion is uniformly coated with the coating material.

An aerospace mirror having a reaction bonded (RB) silicon carbide (SiC) mirror substrate, and a SiC cladding on the RB SiC mirror substrate forming an optical surface on a front side of the aerospace mirror. A method for manufacturing an aerospace mirror comprising obtaining a green mirror preform comprising porous carbon, silicon carbide (SiC), or both, the green mirror preform defining a front side of the aerospace mirror and a back side of the aerospace mirror opposite the front side; removing material from the green mirror preform to form support ribs on the back side; infiltrating the green mirror preform with silicon to create a reaction bonded (RB) SiC mirror substrate from the green mirror preform; forming a mounting interface surface on the back side of the aerospace mirror from the RB SiC mirror substrate, and forming a reflector surface of the RB SiC mirror substrate on the front side of the aerospace mirror. Additionally, the method can comprise cladding the reflector surface of the RB SiC mirror substrate with SiC to form an optical surface of the aerospace mirror.

Methods for depositing silicon oxycarbide (SiOC) thin films on a substrate in a reaction space are provided. The methods can include at least one plasma enhanced atomic layer deposition (PEALD) cycle including alternately and sequentially contacting the substrate with a silicon precursor that does not comprise nitrogen and a second reactant that does not include oxygen. In some embodiments the methods allow for the deposition of SiOC films having improved acid-based wet etch resistance.

Process for manufacturing a nuclear component comprising i) a support containing a substrate based on a metal (1), the substrate (1) being coated or not coated with an interposed layer (3) positioned between the substrate (1) and at least one protective layer (2) and ii) the protective layer (2) composed of a protective material comprising chromium; the process comprising a step a) of vaporizing a mother solution followed by a step b) of depositing the protective layer (2) onto the support via a process of chemical vapor deposition of an organometallic compound by direct liquid injection (DLI-MOCVD).

Nuclear component comprising i) a support containing a substrate based on a metal, the substrate (1) being coated or not coated with an interposed layer (3) positioned between the substrate (1) and at least one protective layer (2) and ii) the protective layer (2) composed of a protective material comprising chromium. The composite nuclear component manufactured by the process of the invention has improved resistance to oxidation, hydriding and/or migration of undesired material.

The invention also relates to the use of the nuclear component for combating oxidation and/or hydriding.