Detection of localized hot electrons in low-pressure large-area microwave discharges

A localized hot-electron region was observed in low-pressure (<3 mTorr) lar ge-area microwave discharges. The region appears in the vicinity of the wav eguiding plasma-dielectric interface in the place of critical plasma densit y. The existence of localized hot electrons is explained on the basis of tr ansit time heating in the resonantly enhanced electric field. The phenomeno n provides experimental evidence that the plasma resonance region plays an active role in heating mechanism in low-pressure microwave discharges. (C) 2000 American Institute of Physics. [S0003-6951(00)00644-6].