Research of the surface modification for two kinds of silicon carbide mirror in common use

Silicon coatings are prepared on mirrors of RB-SiC and S-SiC substrate for surface modification by means of e-beam evaporation,using End-Hall source for ion assisted deposition(IAD).Correlated performance of the silicon coatings is tested and analyzed.The roughness(rms)of the two kinds of substrate is reduced greatly and the reflectivity coated with Ag film is improved simultaneously after surface-modification.Surface qualities of the SiC mirror are obviously improved and the requirement of application is attained.Under the same technical conditions,the modified effect of S-SiC is better than that of RB-SiC.It is because of the different growing characteristic of Si film on the two kinds of substrate.