Abstract: A method for processing a component is provided and includes masking a first portion of the component with a maskant. The maskant includes a slurry having a plurality of particles in a fluid carrier. The plurality of particles comprises at least one of silicon, carbon, one or more rare earth disilicates, monosilicates or oxides, and combinations thereof. The method includes depositing a silicon-based coating on a second portion of the component via a chemical vapor deposition process and removing the maskant and any overlying silicon-based coating from the first portion of the component.

Abstract: Environmental barrier coatings including a bondcoat layer including silicon and a rare earth silicate-based hermetic layer and rare earth silicate-based non-hermetic layer are provided. The rare earth silicate-based hermetic layer is deposited on the bondcoat via a thermal spray process and has an elastic modulus ranging from 100 GPa to 180 GPa. The at least one rare earth silicate-based non-hermetic layer is deposited on the rare earth silicate-based hermetic layer and has an elastic modulus ranging from 50 GPa to 100 GPa. Coated gas turbine engine components and methods for coating gas turbine engine components are also provided.

Abstract: A method for processing a component is provided and includes masking a first portion of the component with a maskant. The maskant includes a slurry having a plurality of particles in a fluid carrier. The plurality of particles comprises at least one of silicon, carbon, one or more rare earth disilicates, monosilicates or oxides, and combinations thereof. The method includes depositing a silicon-based coating on a second portion of the component via a chemical vapor deposition process and removing the maskant and any overlying silicon-based coating from the first portion of the component.

Abstract: Methods for producing surface functionalized silicon nanoparticles like Si-QDs using a continuous gas-phase synthesis by direct pyrolysis of aerosolized higher order liquid silanes like cyclohexasilane (Si6H12) or cyclopentasilane (Si5H10) to produce nanoscale particles are provided. The methods permit control over the particle characteristics i.e., crystallinity, core-shell, size and surface chemistry of Si nanostructures and allow the tuning of the band gap (absorption) and manipulation of photo responsive properties. A wide variety of modifications can be performed using the hydrogen (H) or hydroxyl (OH) groups attached to silicon atoms on the particle surface. The coupling of different molecules or complexes directly to the silicon atoms of the particles allows the engineering of desirable optical, chemical or biological activity to the particles or can act as linkers to agglomerate particles or form porous films.

Abstract: An apparatus and a non-vapor-pressure dependent method of chemical vapor deposition of Si based materials using direct injection of liquid hydrosilane(s) are presented. Liquid silane precursor solutions may also include metal, non-metal or metalloid dopants, nanomaterials and solvents. An illustrative apparatus has a precursor solution and carrier gas system, atomizer and deposit head with interior chamber and a hot plate supporting the substrate. Atomized liquid silane precursor solutions and carrier gas moves through a confined reaction zone that may be heated and the aerosol and vapor are deposited on a substrate to form a thin film. The substrate may be heated prior to deposition. The deposited film may be processed further with thermal or laser processing.

Abstract: An apparatus and non-vapor-pressure dependent methods of producing silicon particles such as nanoparticles (Si-NPs), quantum dots (Si-QDs) and Si-nanocrystals (Si-NCs) as well as particle embedded thin films are disclosed. Nano or micro scale droplets of a liquid silane composition are polymerized in a gas phase with heat or radiation to produce particles that are then collected. Droplets from a droplet generator pass through a flow channel with a reaction zone that is heated or irradiated to form the particles that are collected in a collector. The flow of droplets may be assisted with carrier or flow gases that may be heated. Liquid silane composition solutions may also include metal, non-metal or metalloid dopants and solvents. Particle surfaces can also be passivated or functionalized. Particles and droplets of liquid silane can also be co-deposited and heated to produce particle embedded thin films.

Abstract: Methods for forming silicon thin films and structures with incorporated metals, non-metals, and combinations thereof, liquid precursor compositions useful in such methods, and silicon thin films and structures with embedded heteroatom(s) are described. The compositions are generally liquid at ambient temperature and are comprised of liquid silane(s) and have metal and/or non-metal additives. Metal and non-metal sources include organometallic and organic compounds, respectively. The compositions may also contain a solvent. The compositions may be processed by printing, coating, or spraying onto a substrate and subjected to UV, thermal, IR, and/or laser treatment to form silicon films or structures with embedded heteroatom(s).

Abstract: An apparatus and a non-vapor-pressure dependent method of chemical vapor deposition of Si based materials using direct injection of liquid hydrosilane(s) are presented. Liquid silane precursor solutions may also include metal, non-metal or metalloid dopants, nanomaterials and solvents. An illustrative apparatus has a precursor solution and carrier gas system, atomizer and deposit head with interior chamber and a hot plate supporting the substrate. Atomized liquid silane precursor solutions and carrier gas moves through a confined reaction zone that may be heated and the aerosol and vapor are deposited on a substrate to form a thin film. The substrate may be heated prior to deposition. The deposited film may be processed further with thermal or laser processing.

Abstract: Provided are silicon-containing films with a refractive index suitable for antireflection, articles having a surface comprising the films, and atmospheric-pressure plasma-enhanced chemical vapor deposition (AE-PECVD) processes for the formation of surface films and coatings. The processes generally include providing a substrate, providing a precursor comprising silicon, and reacting the precursor with a gas comprising nitrogen (N2) in a low-temperature plasma at atmospheric pressure, wherein the products of the reacting form a film on the substrate. An antireflection coating made by the process can have a refractive index of about 1.5 to about 2.2. Articles are provided having a surface that includes the antireflection coating.