HIGH-DENSITY PLASMA MODE OF AN INDUCTIVELY COUPLED RADIO-FREQUENCY DISCHARGE

Experimental observations concerning the formation of a high-density plasma in an inductively coupled radio frequency (11.4 MHz) discharge in argon are described. These observations are complemented by probe measurements that provide a quantitative description of plasma properties over an useful range of vapor pressure, 0.02-0.2 Torr, and rf power, 50-400 W. It is shown that a dense plasma of the order of 10(12) cm-3 can be easily formed, having the configuration of a luminous plasmoid embedded in a low-density, 10(10) cm-3, diffuse plasma.