Sifren® 46 (C4F6 or Hexafluorobutadiene) C4F6 has a GWP=0 and it is the most advanced etching gas for critical applications. Its low C/F ratio and its insaturations allow achieving the highest aspect ratios in etching. Uses: Sifren® 46 is suggested for the use in plasma, ion beam or sputter etching in semiconductor devices manufacturing. Information provided by Solvay |