Titanium coating of the inner of a 1 m long narrow tube by double-ended anode coaxial magnetron-pulsed plasmas

In order to reveal the potential of a coaxial magnetron-pulsed plasma (CMPP) reactor for the deposition of thin films on the internal walls of narrow tubes, discharge characteristics and an extended-anode effect were investigated. The extended-anode effect is quite unique in CMPP, and appears due to the deposition of a conductive film onto the surface of an insulator. Three discharge regions corresponding to a plasma breakdown, a steady state and an afterglow were observed and characterized. The breakdown region was extremely dependent on the repetition frequency of the pulsed voltage. Titanium thin films were sputter-deposited onto the inner surface of a narrow glass tube (1000 mm long and 8 mm inner diameter) using double-ended anode coaxial magnetron-pulsed plasmas (DCMPP), to which CMPP was applied for the internal coating of narrow tubes with high aspect ratios of length to inner diameter.