Advanced Vacuum Coating Solutions               

Research & Development

SBIR Research Grants awarded to ZeCoat Corporation


Sheikh, D., "Battery-Powered Process for Coating Telescope Mirrors in Space", Phase I SBIR, NASA, 2017

Abstract: ZeCoat will develop a battery-powered, aluminum deposition process for making broadband reflective coatings in space (wavelength range: 30-nm to 2500-nm). The process uses an array of evaporation filaments powered by batteries contained in pressurized vessels placed in the vacuum of space. The vacuum coating process is scaleable for large mirrors several meters in diameter but is applicable to any size mirror. By simultaneously discharging batteries through individual evaporation filaments, a tremendous amount of energy may be released rapidly. By placing iridium (or a multi-layer interference coating) on the mirror initially (coated on earth), followed by a fresh coat of aluminum in space, the broadband response of the telescope could be extended down to 30-nm.  Current coating technologies limit the reflectance response to 90-nm because of the absorbing fluoride coating which protects the aluminum from oxidation on earth. The ability to coat optics in space offers a tremendous potential benefit to astronomy because the 30-nm to 90-nm region is rich in spectral lines. Since molten metals such as aluminum are held onto a hot tungsten filament by surface tension, the proposed evaporation process will work in zero-gravity. A high aluminum evaporation rate has been shown to produce the least scattering and most highly reflecting aluminum coatings, particularly in the vacuum UV spectral region. To achieve future wavefront requirements over a large primary mirror, it is likely that many evaporation sources will be required. By placing the power supply (the battery) very near each evaporation filament, electrical losses are minimized. In Phase I, we will demonstrate feasibility using prototype battery-powered unit will be designed and manufactured, and the coating process will be developed and tested in a simulated space environment.

Sheikh, D., "Low-Stress Silicon Cladding for Surface Finishing Large UVOIR Mirrors", Phase II SBIR, NASA, 2014

Abstract: In this Phase I research, ZeCoat Corporation demonstrated a low-stress silicon cladding process for surface finishing large UVOIR mirrors. A polishable cladding is desired for SiC optics so they may be figured in less time, and so they may be polished to levels suitable for UVOIR astronomy. ZeCoat has filed a provisional US patent application for the technology. The proposed process is directly scalable to SiC mirrors several meters in diameter. The process is based on a novel, low temperature, ion-assisted, evaporation technique (IAD), whereby the coating stress of a silicon film may be manipulated from compressive to tensile, in order to produce a near-zero net stress for the complete layer. A Si cladding with little intrinsic stress is essential to allow thick coatings to be manufactured without cracking. A low stress coating also minimizes substrate bending that would otherwise distort the figure of very lightweight mirrors.

Sheikh, D., "Broadband Reflective Coating Process for Large FUVOIR Mirrors", Phase I SBIR, NASA, 2014

Abstract: ZeCoat Corporation will develop and demonstrate a set of revolutionary coating processes for making broadband reflective coatings suitable for very large mirrors (4+ meters). Decades of research and flight missions (Hubble, GALAX and FUSE) have utilized metal fluorides such as, MgF2 and LiF, applied to Al to achieve FUVOIR coating requirements. While metal fluoride-protected Al remains the best option for meeting broadband reflectance requirements (90-nm to 2500-nm), ZeCoat offers a means to build upon the best known and proven coating recipe (the GSFC 3-step process) by: 1) utilizing ZeCoat's unique precision motion-controlled deposition system to uniformly apply a 5-nm layer (a requirement of the GSFC recipe) of coating material to a large coating area, 2) protecting mirror assemblies from damaging high temperatures by heating only the mirror surface using radiant heat (the GSFC process requires a 220C metal-fluoride deposition temperature), 3) using an FUV reflectometer (120-nm to 180-nm) integrated into the coating chamber to optimize the coating process for FUV reflectance and 4) investigating the feasibility of using a layer of Sn to protect LiF from degradation due to atmospheric moisture and organic contamination during ground storage and re-evaporate the Sn once the observatory is placed in-orbit.

Other SBIR research grants awarded to CEO and founder, David A. Sheikh

  1. Sheikh, D., Fulton, M., “High Reflectivity, Broad-Band Silver Coating”, Phase II SBIR, NASA, 2011.
  2. Sheikh, D.,Fulton, M.,  “Very Large Solar Rejection Filter for Laser Communication”, Phase II SBIR, NASA, 2011.
  3. Sheikh, D, “Low Stress Silicon Cladding for Optical Finishing”, Phase II SBIR, MDA, 2007.
  4. Sheikh, D., “X-Ray Hard Mirror Coating for Spacecraft and Interceptors”, Phase II SBIR, MDA, 2007.
  5. Sheikh, D., “Durable Silver Mirror Coating Via Ion Assisted, Electron Beam Evaporation for Large Aperture Optics”, NASA Phase II SBIR, 2005.
  6. Sheikh, D., “Dual Band Mirror System on Flexible Membrane for High Energy Laser Applications”, Air Force, Phase II, 2005..
  7. Sheikh, D., Dummer, S. R, “Extremely Uniform VLA Coating for Large Aperture Optics” – MDA Phase I SBIR, 2002.
  8. Sheikh, D., Baczuk, J. A., “Optical Monitoring of VLA Coating Processes with Real-Time Hyperspectral Imaging” – MDA Phase I SBIR, 2002.
  9. Sheikh, D., “Manufacture of X-Ray Mirror Replicas From Structural Nanolaminate Composites”, Proposal Number 00-1 17.02-9595 (Chron: 000406), 2000.
  10. Abusafieh, A., Sheikh, D., Clark, H., “Lightweight Carbon Fiber Composite Mirror Fabrication”, SBIR Phase II Final Report, Contract No. NAS8-8705, February 2000.
  11. Sheikh, D. “Surface Leveling of Composite Mirror Membranes via Polymeric Vapor Deposition”, SBIR Phase I Final Report, Contract No. NAS5-99022, July 31, 1999.
  12. Sheikh, D., Ruffoni, J., “Fiber Print-Through Avoidance for Composite X-Ray Mirrors”, SBIR Phase II Final Report, Contract No. NAS8-97274, August 1999.
  13. Sheikh, D., “A Thin Film Polymer Figuring Process For Composite Mirror Correction”, SBIR Phase I & II Final Report, Proposal Number 99-1 13.01-57000A (Chron: 991685), 1999.
  14. Sheikh, D., Clark, H., “Thermally Stable, Large Aperture Submillimeter Sensors”, SBIR Phase II Final Report, Contract No. NAS7-1398, July 1997.