Cryogenic TOF-SIMS Around Sublimation Temperature of Quench-Condensed Noble Gas (Ne, Ar, and Kr) Films

A possible TOF-SIMS analysis of surface phase transitions has recently been proposed for limited cases such as polymers and ionic liquids. In the present study, we have extended this analysis to quench-condensed noble gas films. The newly developed cryogenic TOF-SIMS allowed both measurements of TOF-SIMS below 4 K, and low-energy ion scattering spectroscopy that is used to prepare a clean surface. It was found that the TOF-SIMS intensity variation by increasing the temperature at a constant ramp rate (temperature-programmed TOF-SIMS) shows steep changes due to sublimation. Thus, the possibility of analyzing the surface phase transition at the local region defined by the incident ion beam of (cryogenic) TOF-SIMS was demonstrated in the present study.