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Publication Citation: Effect of Alternating Ar and SF6/C4F8 Gas Flow in Si Nano-Structure Plasma Etching

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Author(s): Lei Chen; Vincent K. Luciani; Houxun H. Miao;
Title: Effect of Alternating Ar and SF6/C4F8 Gas Flow in Si Nano-Structure Plasma Etching
Published: August 01, 2011
Abstract: Si is very reactive to normal plasma etchants such as fluorine based chemicals and the reactions are inherently isotropic. To fabricate small and/or high aspect ratio nanoscale structures in Si, anisotropic profile is necessary. SF6 combined with C4F8 has been demonstrated as a good gas combination for anisotropic Si etching [6]. In this study, Ar gas was introduced into the etching chamber to improve Si etching rate. In addition to mix Ar with F etching gases directly, an alternating Ar and F gas flow process was proposed. It is interesting to see that the Si etching profile, etching rate and etching selectivity are all improved by alternating Ar bombardment and SF6/C4F8 etching steps. The Si etching rate is determined by the Ar treatment step in alternating Ar and F two step process.
Citation: Microelectronic Engineering
Volume: 88
Issue: 8
Pages: pp. 2470 - 2473
Keywords: Plasma, Etching, Silicon
Research Areas: Etch
PDF version: PDF Document Click here to retrieve PDF version of paper (406KB)