Low-Stress Silicon Cladding for Surface Finishing Large UVOIR Mirrors, Phase II

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.

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Field Value
Groups
  • AmeriGEOSS
  • National Provider
  • North America
Tags
  • amerigeo
  • amerigeoss
  • ckan
  • geo
  • geoss
  • national
  • north-america
  • united-states
isopen False
license_id us-pd
license_title us-pd
maintainer TECHPORT SUPPORT
maintainer_email hq-techport@mail.nasa.gov
metadata_created 2025-11-30T09:25:12.395098
metadata_modified 2025-11-30T09:25:12.395102
notes 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.
num_resources 4
num_tags 8
title Low-Stress Silicon Cladding for Surface Finishing Large UVOIR Mirrors, Phase II