Ionization, Electron Attachment And Drift In CF4

摘要

Thispaper have measured the density-normalized effective ionization coefficients (??-??)/N, (?? and ?? are the ionization and attachment coefficients, respectively) and the electron drift velocity Ve in Carbon tetrafluoride (CF4) using a pulsed Townsend technique. The overall density-normalized electric field strength E/N ranged from 50 to 250 Td (1 Td=10-17 Vcm2). From the above plots for (??-??)/N, we have derived the limiting or critical field strength, (E/N)lim??128 Td, which is the value of E/N at which (??-??)/N=0.