Secondary electron energy spectra emitted from radio frequency biased plasma electrodes

The ion-induced secondary electron energy spectra from a radio frequency bi ased (13.56 MHz) electrically insulating (Al2O3) plasma electrode surface i mmersed in a separately powered inductively coupled plasma are studied both experimentally and theoretically. Radio frequency (rf) electrode bias volt ages of 140 and 285 V (peak to ground) are employed and the complete electr on energy spectra emitted from the electrode and accelerated by the rf shea th are measured 14 cm from the rf biased electrode using a differentially p umped retarding potential analyzer. A collisionless radio frequency Child-L angmuir sheath model is used to explain the experimentally measured electro n energy spectra. (C) 1999 American Institute of Physics. [S0003-6951(99)03 027-2].