Radiation resistant and reproducible fluorine-based coatings of H-maser storage box for a possible use in space

An electron microscopical study of PTFE coatings of H-maser´s storage box revealed a well pronounced morphology comprising from lathlike overlapped PTFE crystals that were suggested to act as the traps for active H-atoms. If was found that they were formed at any regime of sintering with subsequent annealing or quenching of the coatings irrespective of the change in their sizes. The latter was supposed to be one of the reason of the poor reproducibility of the H-maser frequency. The possible absorption of H-atoms and residual gases from H-maser vacuum system by a storage box surface, as well as the organic and inorganic impurities, surfactants, radicals and chain cilic on the surface can also lead to formation of the local active recombination centers of H-atoms. These result in reducing H-maser life time and widening its spectral line. The novel technique of the fluorine-based gaseous monomers is developed. The coatings comprise the crosslinked non-crystallizable polymer networks with the enhanced resistance to the deteriorating action of H-atom bombardment. The coating produced by the proposed technique are better reproducible due to simplicity in controlling discharge regime by relevant equipment and possibility for determining chemical content with the help of XPS and FTIR. The use in an operating H-maser the coatings produced from glow-discharge in perfluorokerosene and C₄F₈ atmosphere demonstrated their promising properties in the working condition under the action of high irradiation closes