摘要:
Embodiments for an apparatus and method for depositing one or more layers onto a substrate or a freestanding shape inside a reaction chamber operating at a temperature of at least 700° C. and 100 torr are provided. The apparatus is provided with a feeding system having injection means for differential pre-reactions and/or pre-treating of a plurality of gases or gas mixtures, tailoring the distribution of a plurality of gas-phase species, yielding a deposit that is substantially uniform in thickness and chemical composition along the substrate surface. In one embodiment, the apparatus further comprises a sacrificial substrate that further helps achieving thickness and chemical uniformity on the substrate, by imitating a continuous surface to deposit on and thus preventing any disturbances in the flow pattern especially towards the edge of the substrate.
摘要:
Disclosed herein is a crack-free protective coating comprising at least one of aluminum nitride, aluminum oxide, aluminum oxynitride or combinations thereof. Disclosed herein too is a method for making an article comprising disposing a protective coating comprising at least one of aluminum nitride, aluminum oxide, aluminum oxynitride or combinations thereof upon a substrate comprising pyrolytic boron nitride, pyrolytic graphite and/or carbon doped boron nitride.
摘要:
A method of making a cubic halide scintillator material includes pressing a powder mixture of cubic halide and at least one activator under conditions of pressure, temperature, residence time and particle size effective to provide a polycrystalline sintered cubic halide scintillator having a pulse height resolution of from about 7% to about 20%. The conditions include a temperature ranging from about ambient temperature up to about 90% of the melting point of the cubic halide, a pressure of from about 30,000 psi to about 200,000 psi, a pressing residence time of from about 5 minutes to about 120 minutes and an average cubic halide particle size of from about 60 micrometers to about 275 micrometers.