Diagnosis of plasma glow discharge energy parameters in the processes of treatment small diameter long tubes

Abstract

Energy characteristics of glow discharge plasma initiated in the hollow cathode while treating of inner surface of small-diameter tubes, which include waveguides for microwave radiation, were studied with a probe technique. It was shown that at the pressure in the gas discharge chamber of 53 Pa and discharge current of 75 mA, in the cathode cavity geometry studied a sufficiently dense plasma with the concentration of charged particles at 1,6•1010 cm-3 which are characterized by a high heterogeneity on cavity height (40 ... 60%) was generated. It was also shown that an effective mechanism of influence on the plasma distribution inside of the cathode cavity where L >> D is the cathode-anode distance change. Such a reduction in length from 40 to 20 mm increases the uniformity of the ion and electron distribution to 15 ... 20%, and the introduction of additional anode in the discharge circuit – to 8 ... 10%.