Spatially resolved detection of O atoms in etching plasmas by two-photon laser-induced fluorescence

Abstract

Spatially resolved concentration profiles of ground-state oxygen atoms in O2/Ar plasmas have been obtained under loaded etching conditions through the use of a two-photon laser excitation process. These results provide a quantitative measure of the reactive atom concentration gradient during etching of kapton or graphite on the rf-driven electrode. The effects of load, ion bombardment, and diffusion on the reactive atom concentration may be directly monitored by this in situ, unobtrusive, three-dimensional probe technique.