Some Electron Temperature Measurements for a Low Pressure Discharge Tube by means of Probe Methods

There are many methods such as a probe method, aspectroscopic method, a microwave method to know the low pressure plasma properties. Especially, a probe method is mainly used by the merits which this method is able to measure directly various parameters of the plasma (electron temperature and electron density) and to operate easier than the other methods. A few works have been carried out for the glow discharge in a low pressure (10 mtorr, Ar gas), so that this experiment has been done for the purpose of expounding the characteristics of the low gas pressure tube by using a single probe method and a double probe method. As the result, it was obtained as follows. 1) The negative glow has the greater part of the discharging column and positive column has not more than one third of the discharge column. 2) In the case of measuring the characteristics of a discharge tube which is applied more than 1 kV, the double probe method is more suitable than the single probe method. 3) A negative glow has the Maxwellian distribution for both the normal glow discharge and an initial state of the abnormal glow discharge. 4) The electron temperature, the electron density and electric conductivity is nearly equal to 5×10^4°K, 8×10^8cm^<-3> and 22.4&mho