Surface Analysis by Laser Ionization

A new reflecting time of flight mass spectrometer is described which allows to display absolute saturation of laser ionization. For each specific charge q/m the new TOF instrument creates two ion bunches containing the ions originating respectively inside and outside a sharply‐limited acceptance volume of the spectrometer. Thus quantification of laser ionization is possible. This method has been applied to non‐resonant KrF excimer laser post‐ionization of sputtered metal atoms. It may be developed into a very sensitive tool for quantitative surface analysis.