Preparation Of Copper-Ruby Glasses By Sputtering: The Effect Of Atmosphere On The Growth Of Copper Particles

Copper-ruby glasses were prepared by the sputtering method and the effect of reducing treatment was examined. The reducing was carried out either during sputtering or heat treatment. Optical absorption was related to the growth of copper particles. The results are summarised as follows: (i) The volume fraction of copper particles in the glasses which are heat-treated in air increases with the addition of hydrogen in the sputtering gas. (ii) The copper particles do not grow larger than 8nm by heat treatment in reducing atmosphere, whereas they grow as large as 12nm in air. (iii) Reducing during heat treatment gives a pronounced effect only when sputtering was not carried out under reducing conditions.