Silicon Carbide Grid Supports for X-Ray Telescopes

PhotonFoils will develop single crystal silicon carbide grids and membranes for X-ray telescopes and laboratory instruments. SiC grids are needed for microcalorimeter shields onnbsp;Lynx, which cannot meet design requirements with existing grid materials. SiC grids can also also improve the signal stability of cooled imaging X-ray detectors, such as Lynx HDXI and Axis, by reducing contaminant accumulation in the optical path. NASA requires fine-featured, durable grids as membrane supports for X-ray, EUV, and particle detectors.nbsp;SiC also offers a path for providing membrane support mesh with superior X-ray transmittance, usable in instruments such as spectrometers, without generating fluorescence artifacts associated with metal grids. The Lynx X-ray Grating Spectrometer willnbsp;need an Optical Blocking Filter, for which SiC would provide a superior grid. Our proposed SiC grids would provide far superior heat shedding compared to existing grids used for near-solar missions. In addition to grids, our proposed fabrication technology can produce high strength, high bandgap membranes for laboratory X-ray windows, transducers,nbsp;and transmissive detectors (e.g. X-ray dosimeters and position monitors). These membranes could be used for LWIR filter substrates, or for back-illuminated UV detectors with high collection efficiency.nbsp;In Phase I we prototypednbsp;methods to fabricate single-level SiC grids.nbsp; In Phase II we will employ these methods to fabricate 2-Level grids, with geometries analogous to the silicon grids used for Hitomi SXS.nbsp; In Phase II, we will also fabricate SiC membranes, and single-level grids, for various terrestrial and space telescope applications.