Fluorocarbon Films from Plasma Polymerization of Hexafluoropropylene and Hydrogen

Abstract

AbstractFluorocarbon polymers exhibit excellent dielectric properties; however, their limited thermal and mechanical stability render them unsuitable for most interlevel dielectric applications. In this work we explore the plasma assisted deposition of fluorocarbon films from hexafluoropropylene (C3F6) and hydrogen in order to understand how the mechanical and thermal properties might be improved. Plasma activation and ion bombardment promote the formation of a crosslinked, amorphous film structure. Several process parameters were examined including temperature and rf driving frequency. The results demonstrate that crosslinked fluorocarbon polymers with enhanced mechanical strength can be produced from C3F6 in a plasma environment. Most of the films studied here had dielectric constants in the range of 2 to 2.5. Thermal stability (to 400 °C), however, was not achieved.