FAST NEUTRAL BEAM FOURIER-TRANSFORM ION-CYCLOTRON RESONANCE MASS-SPECTROMETRY FOR ANALYSIS OF INSULATING AND CONDUCTIVE MATERIALS

The use of an autoneutralizing fast neutral SF6 beam (FNB) for secondary ion quadrupole mass spectrometry of refractive samples has been demonstrated previously. Here, we demonstrate the FNB technique for generation and high-resolution Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometric detection of ions from a wide variety of samples. The fast neutral beam generates abundant secondary ions from both conductive and insulating samples for detection in an open-ended ICR ion trap, as demonstrated by representative mass spectra of methyl stearate, fluorocarbon polymers, gramicidin S, and fullerenes. Optimization of the FNB-FT-ICR-MS experiment is discussed in detail, with particular emphasis on analysis of insulating materials which are not readily analyzed by ion-bombardment secondary ion mass spectrometry.