Characterization of hydrogenated silicon carbide produced by plasma enhanced chemical vapor deposition at low temperature

Abstract

A new technology has been developed to grow layers of amorphous hydrogenated Silicon Carbide in vacuum, at temperatures below 100-120°C by Physical Enhanced Chemical Vapour Deposition (PE-CVD) technology. The layers have been used either to improve the surface quality of SiC mirror substrates (produced by methods different of the CVD approach, like e.g. sintered SiC) as a super-polishable cladding coatings, or to form self-sustaining thin mirrors in SiC. It should be noted that the PE-CVD claddings can be applied also to substrates different than SiC, as e.g. metals like Al or Kanigen, in order to create a high durability polishable external layer. It this paper we present the results of a wide characterization of the new material, considering the mechanical, structural and optical properties that are the most indicative parameters for its application in optics, with particular reference to the production of mirrors for ground and space astronomical applications.