Negative ion formation in the scattering of CF+3 from graphite
The scattering of CF+3 from highly oriented pyrolytic graphite results in the formation of CF–3. Comparison is made with CF+3 scattering from a metal and from an insulator surface, which do not yield negative molecular ions. The outcome of the charge transfer processes that occur as CF+3 approaches a surface is critically dependent on the electronic properties of that surface. The ability to produce a stable negative ion close to a surface may be an important factor in the etching efficiency of the CF+3 molecule.
