MONTE-CARLO SIMULATION FOR ELECTRON-NEUTRAL COLLISION PROCESSES IN NORMAL AND ABNORMAL DISCHARGE CATHODE SHEATH REGION

Electron-neutral collision processes in helium DC normal and abnormal discharges have been studied using Monte-Carlo simulation (MCS). Four types of collisions (elastic, metastable excitation, excitation and io nization collision) are considered. Comparing normal discharge with ab normal discharge, we find that the number of collisions decreases and the collision rates increase through the cathode region in abnormal di scharge. The collision rates calculated from electron instantaneous en ergy is different than that calculated from electron mean energy. The results also show that the elastic collision is the greatest proportio n and plays an important role in electron-neutral collision processes in the cathode fall region. The effects of collision on the electron m ean energy is also studied. Copyright (C) 1996 Elsevier Science Ltd.