Secondary ion mass spectrometry for superconducting radiofrequency cavity materials

Historically, many advances in superconducting radio frequency (SRF) cavities destined for use in advanced particle accelerators have come empirically, through the iterative procedure of modifying processing and then performance testing. However, material structure is directly responsible for performance. Understanding the link between processing, structure, and performance will streamline and accelerate the research process. In order to connect processing, structure, and performance, accurate and robust materials characterization methods are needed. Here, one such method, secondary ion mass spectrometry (SIMS), is discussed with focus on the analysis of SRF materials. In addition, several examples are presented, showing how SIMS is being used to further understanding of material-based SRF technologies.