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Optimizing C60 incidence angle for polymer depth profiling by ToF‐SIMS

The introduction of C60+ as a sputter ion beam for ToF‐SIMS has made it possible to acquire molecular depth profiles on a wide variety of polymers. However, previous studies have indicated that certain classes of polymers undergo sputter‐induced damage when bombarded with C60+ that prevents obtaining stable molecular secondary ion signals as a function of depth. A number of different analytical parameters have been previously explored in attempts to improve depth profiling of these polymer classes. In this study, the effect of C60+ incident angle on the ability to depth profile polycarbonate (PC) and polystyrene (PS) was investigated at angles from 48° to 76° with respect to the sample normal. This study indicates that the highest sputtering angle provided the best conditions for molecular depth profiling. Copyright © 2010 John Wiley & Sons, Ltd.