Pure Chemical F-Atom Etching of Silicon Flamm Formulas and Doping Effect

Pure Chemical F-Atom Etching of Silicon Flamm Formulas and Doping Effect 

Etching of silicon by fluorine atoms is the most practically important and the best characterized surface etch process (Flamm, 1989, 1990 Winters Cobum, 1992 Lieberman Lichtenberg, 1994). We consider first the pure chemical mechanism of the process, leading to isotropic silicon etching then we discuss ion energy-enhanced anisotropic etching. 

The Flamm formulas lead to the expression for the silicon-to-silicon dioxide etching selectivity  

Ion Energy-Driven F-Atom Etching Process Main Etching Mechanisms 

High fluxes of energetic ions increase the etch rates of silicon five- to ten-fold with respect to the pure chemical etching described by Flamm formulas (8-43) and (8 4). A single 1 KeV Ar+ ion is able to cause the removal of 25 Si atoms and 100 F atoms (to compare, such an 

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