Inductively Coupled Plasma Source for the Gaseous Electronics Conference RFReference Cell

摘要

In order to extend the operating range of the GEC RF Reference Cell, we developedan inductively coupled plasma source that replaced the standard parallel-plate upper-electrode assembly. Voltage and current probes, Langmuir probes, and an 80 GHz interferometer provided information on plasmas formed in argon, chlorine, and nitrogen at pressures from 0.1 Pa to 3 Pa. For powers deposited in the plasma from 20 W to 300 W, the source produced peak electron densities between 10(exp 10)/cubic cm and 10(exp 12)/cubic cm and electron temperatures near 4eV. The electron density peaked on axis with typical full-width at half maximum of 7 cm to 9 cm. Discharges in chlorine and nitrogen had biomodal operation that was clearly evident from optical emission intensity. A dim mode occurred at low power and a bright mode at high power. The transition between modes had hysteresis.