Secondary ion emission from cesium salts under megaelectronvolt ion bombardment: comparative study and beam secondary effects

Abstract

A comparative study of the secondary ion yields of various cesium salts (halide, nitrate and sulphate) under bombardment of Ar ions at 9 MeV has been performed using time-of-flight detection techniques. Exceptionally high values (close to 100%) are reported with nitrate and sulphate. This result seems related to the presence of oxygen from which chemically active radicals are formed. However, the use of highly collimated primary ion beams allows observation of a yield variation as a function of primary ion fluence which is similar to what has often been observed with conventional secondary ion mass spectrometry.