Selective Plasma Etching of Polyphenolic Composite in O2/Ar Plasma for Improvement of Material Tracking Properties

Abstract

Compositing with suitable fillers is a common strategy to improve the electrical insulation properties of polymer materials, which is limited by the carbonization of protruding surface polymer. To resolve this, we performed an Ar/O2 plasma etching on glass-filled polyphenolic composite to uncover the fillers by selective removal of the surface polymer. Exposure of the glass fillers increased the performance level up to 65%, which enabled the material to be used as insulator for commercial applications. Plasma diagnostics with probe measurements and emission spectroscopy revealed that the etching rate was mostly influenced by the neutral oxygen atom density rather than O2 or Ar ions. Additionally, Ar content in the reactor chamber could control the densities of species, i.e., neutral oxygen density, and thereby polymer etching rate.