Review of ion energy and angular distributions in capacitively coupled RF plasma reactors

Summary form only given. We present a historical review and discussion of previous works on ion energy and angular distributions (IED and IAD) arriving at the target in the collisionless regime. This regime is of great interest to experimentalists and modelers studying the new generation of high density sources in which the sheath is much thinner than in the conventional RIE systems. The purpose of the review is to assess what has been done so far, and to clarify some issues about sheaths in high density systems. Having determined the important parameters, we will show some particle-in-cell simulation results of a dually excited capacitively coupled plasma in which the sheath ions roughly see the scaling as in high density sources. The results show that when /spl tau//sub ion///spl tau//sub RF/<1, the oscillating voltage and width of the RF sheath significantly affect the IEDs, where /spl tau//sub ion/ is the ion transit-time and /spl tau//sub RF/ is the RF period.