Analysis of TOF-SIMS spectra from fullerene compounds

We analyzed TOF-SIMS spectra obtained from three different size of fullerenes (C60, C70 and C84) by using Ga+, Au+ and Au3+ primary ion beams and investigated the fragmentation patterns, the enhancement of secondary ion yields and the restraint of fragmentation by using cluster primary ion beams compared with monoatomic primary ion beams. In the TOS-SIMS spectra from C70 and C84, it was found that a fragment ion, identified as C60+ (m/z = 720), showed a relatively high intensity compared with that of other fragment ions related to C2 depletion. It was also found that the Au3+ bombardment caused intensity enhancement of intact molecules (C60+, C70+ and C84+) and restrained the fragmentation due to C2 depletion.