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 seconda ry ion quadrupole mass spectrometry of refractive samples has been dem onstrated previously. Here, we demonstrate the FNB technique for gener ation and high-resolution Fourier transform ion cyclotron resonance (F T-ICR) mass spectrometric detection of ions from a wide variety of sam ples. The fast neutral beam generates abundant secondary ions from bot h conductive and insulating samples for detection in an open-ended ICR ion trap, as demonstrated by representative mass spectra of methyl st earate, fluorocarbon polymers, gramicidin S, and fullerenes. Optimizat ion of the FNB-FT-ICR-MS experiment is discussed in detail, with parti cular emphasis on analysis of insulating materials which are not readi ly analyzed by ion-bombardment secondary ion mass spectrometry.