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This NASA invention is an innovative process for fabricating high-area binary phase photon sieves with improved optical efficiency for EUV imaging applications. Binary phase photon sieves have been demonstrated for a variety of optical and x-ray applications. Photon sieves must be wide, super-thin, and etched with precise holes to refract light. Each step in NASA's photon sieve fabrication process includes considerations to protect the resulting sieves, such as leaving a honeycomb of thicker material to support the membrane and prevent tearing. The process starts by using a silicon-on-insulator wafer, includes pattern and etch-sieve pattern, and ends with a released photon sieve. The inventors have produced an 8 cm-diameter silicon sieve that is 100 nm thick including hole sizes of 2 µm in diameter with 2 µm spacing. Additionally, a similar structure has been demonstrated in niobium, with 8 cm in diameter with the same silicon hexagonal support frame. This novel process enables the fabrication of photon sieves for EUV imaging applications. While the process was initially developed to fabricate photon sieves for solar science and astronomy, it could also be used to generate metamaterial/frequency selective surface structures from the UV to THz frequency ranges. This NASA invention is a Technology Readiness Level (TRL) 4 (prototype validation in a laboratory environment) technology and is available for patent licensing.

The manufacturing process, building on techniques showcased in LEW-TOPS-151, employs a novel acoustic mixing technique to coat spherical C103 powder particles with a uniform distribution of sub-200 nanometer yttria particles. During laser powder bed fusion additive manufacturing, layer-by-layer remelting disperses these yttria particles uniformly throughout the component microstructure. This eliminates the expensive, time-consuming mechanical alloying steps traditionally required for ODS alloys while enabling near-net-shape fabrication of complex geometries. Performance testing demonstrates substantial improvements: GRC103y exhibits double the yield strength at 800°C and 1.5x the yield strength at 1,400°C compared to baseline C103. The alloy also shows superior thermal stability: after one hour at 1,500°C, GRC103y retains 90% of its room temperature strength compared to only 67% for C103. Preliminary creep testing at 1,300°C and a stress of 50 MPa indicates significant improvements in creep resistance by 2539 times over baseline C103. Furthermore, GRC103y maintains excellent formability, allowing manufacturers to use traditional fabrication methods when desired. While NASA originally developed GRC103y for rocket propulsion and hypersonic vehicle applications, the alloy offers value across multiple industries. Aerospace companies can achieve weight savings or push systems to higher temperatures, while the alloy's compatibility with commercial oxidation coatings makes it suitable for environments requiring oxidation protection. GRC103y is currently available for patent licensing.