Radio frequency plasma jet applied to coating of internal walls of narrow tubes

Abstract

A novel method for deposition of thin films onto internal walls of narrow tubes is described. The method is based on sputtering and/or evaporation of the end of a nozzle in a radio frequency plasma jet system (RPJ). A Ti nozzle of 5 mm outer and 2 mm inner diameter, respectively, was used for TiNx film deposition onto Si substrate inserts fixed on the internal wall of a steel tube of 8 mm bore. The axial distribution of the film thickness along 20–50 mm of deposited area was measured. An effect of separation of macroparticles was found in the RPJ. This enabled the growth of high quality films on the tube walls at rf power levels exceeding 100 W.