Carbon-Shunting Arc Plasmas
ByKoichi Takaki, Ken Yukimura
Pages 9

Shunting arc discharge is a pulsed plasma source of metals and semimetal materials including carbon (C) and is ignited without any trigger sources at a wide range of gas pressures, from vacuum to atmospheric pressure under identical discharge conditions. Even at atmospheric pressure, a plasma can be produced because the rod is heated up by rod current to emit metal vapor so as to generate gas breakdown around the rod. When the temporally increasing voltage across the rod matches the plasma ignition voltage, the shunting plasma is ignited. The plasma ignition is triggerless and thus does not require an external power source. The shunting plasma can be produced in not only arc but also glow discharge modes. When a pulsed power source with a controlled pulse duration is used to obtain a glow plasma only, a stable steady-state glow can be obtained under a current with a duration of less than 10 μs and a consumed power of several tens of kilowatts. In this entry, an application of the C shunting glow and arc plasmas for the preparation of thin film and its process are described.