Evaluation of Temperature Dependency of Gas Permeability on Various Kinds of Elastomers

Abstract

　Gas permeation test equipment was developed to measure the gas permeability through O-ring shape elastomers under actual condition of semiconductor manufacturing such as high vacuum and high temperature. The temperature dependencies of gas permeability on three kinds of elastomers, silicone (VMQ), fluoroelastomer (FKM) and perfluoroelastomer (FFKM), were investigated. Permeation rate for all materials increased as temperature increased. O₂ and N₂ gas permeation rate through VMQ was much higher than that through the other materials, especially in lower temperature. Moreover, the temperature dependencies of gas permeability with VMQ were completely different from those of FKM and FFKM. This was coming from different polymer structure which caused difference of solubility and diffusivity between silicon and fluoroelastomers.