Voltage-current characteristics of high-current glow discharges

The voltage-current characteristics of glow discharges in gas mixture (N-2: O-2=8:2) at a pressure of 10 Torr were obtained with the discharge current up to 150 A. Parallel-plane electrodes with a diameter of 10.7 cm and a dis charge chamber with co-axial geometry were used to produce glow discharge w ith high current. The glow discharge voltage was almost constant until the whole surface of the cathode was covered with glow, i.e., until the dischar ge current became 3.7 A in our experimental condition (a normal glow discha rge mode). The voltage, however, increased with the current when the glow c overed over the cathode (an abnormal glow discharge mode). The electron den sity in positive column of the high-current glow discharge was obtained to be 3x10(11) cm(-3) from Langmuir probe measurements. (C) 2001 American Inst itute of Physics.