Mixed polymer sample evaluation using gentle secondary ion mass spectrometry and multivariate curve resolution

Abstract

The investigation of fragment ions from macromolecules is crucial for the interpretation of time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) data, although it is often difficult because fragmentation mechanisms in secondary ion mass spectrometry have not been clarified. In this study, multivariate curve resolution (MCR) was applied to extract a pure component spectrum, and gentle SIMS (G‐SIMS) was applied to the investigation of fragment ions from polymers. Several types of polyethylene glycol were diluted in toluene solutions, and then thin films of them were formed on Si wafers using a spin coater. The samples were measured with TOF‐SIMS using Mn+, Bi+, and Bi3+ and then the TOF‐SIMS spectra data were analyzed with G‐SIMS and MCR. As a result, relationships between fragment ions were clarified using G‐SIMS, and a pure sample spectrum of each polyethylene glycol sample was extracted by MCR. Copyright © 2012 John Wiley & Sons, Ltd.