HIGH-FREQUENCY MAGNETOPLASMAS IN ELECTRONEGATIVE GASES

Discharges in electronegative gases are routinely used for the sub-mic ron etching of thin films in the microelectronics industry. Because of the strong electronegative character of these gases, negative ions co nstitute a significant fraction of the charged particles content of th e discharge. The presence of these negative charge carriers affects th e whole behavior of the discharge and in particular, its electron powe r balance. This article compares a few characteristics of a high-densi ty plasma produced either in SF6 or in Cl-2 with those of an argon pla sma under similar experimental conditions. We show that the plasma pre sents characteristics when the gas is electronegative that significant ly differ from those observed in argon.