Plasma–Assisted Materials Processing for Manufacturing of the VLSI Circuits

Abstract

The reactive ion etching of silicon and GaAs in ionized gas of CF_4-xCl_x, O₂, SF₆, and their mixtures with oxygen and hydrogen have been studies. The ion of low energy enhance the rate of heterogeneous reactions and the desorption of volatile compounds. Oxide and fluoride layer on the surface increases with the increase of bombarding ion energy. The formed surface layer at these conditions reduces the process of etching of GaAs. Etching in CF₂Cl₂ plasma is the most anisotropic, because the low amount of fluorine results the increase of concentration of CF_x radicals. The formation of the altered layer and anizotropical etching through a mask may be described qualitatively by the phenomenological model.