Xenon Plasma Focused Ion Beam Milling for Obtaining Soft X-ray Transparent Samples

We employ xenon (Xe) plasma focused ion beam (PFIB) milling to obtain soft X-ray transparent windows out of bulk samples. The use of a Xe PFIB allows for the milling of thin windows (several 100 nm thick) with areas of the order of 100 mu m x 100 mu m into bulk substrates. In addition, we present an approach to empirically determine the transmission level of such windows during fabrication by correlating their electron and soft X-ray transparencies. We perform scanning transmission X-ray microscopy (STXM) imaging on a sample obtained by Xe PFIB milling to demonstrate the conceptual feasibility of the technique. Our thinning approach provides a fast and simplified method for facilitating soft X-ray transmission measurements of epitaxial samples and it can be applied to a variety of different sample systems and substrates that are otherwise not accessible.

Automated summary

This study focuses on obtaining soft X-ray transparent windows using xenon plasma focused ion beam (PFIB) milling, with an empirical method to determine the transmission level of the windows during fabrication. Additionally, scanning transmission X-ray microscopy (STXM) imaging is used to demonstrate the feasibility of the technique. The thinning approach provides a fast and simplified method for soft X-ray transmission measurements of epitaxial samples.