Characteristics of silicon etching by silicon chloride ions

Abstract

Plasmas generated from halogen-containing gases, such as Cl2 or HBr, have been widely used in gate etching processes for semiconductor chip manufacturing. Such plasmas may contain silicon halide ions formed by the ionization of etching products that enter the plasma. In this study, to illustrate Si etching by such silicon halide ions, the sputtering yield of Si by SiClx+ (with x = 1 or 3) ions has been obtained as a function of the incident ion energy by using a mass-selected ion beam injection system. It has been found that, at sufficiently low energy, the incidence of SiCl+ ions leads to the deposition of Si which may affect profile control in microelectronic device fabrication processes.