Development of Laboratory Micro‐ <scp>XRF</scp> Spectrometer Based on Ellipsoidal Curved Crystal

ABSTRACT In this paper, we present a laboratory micro x‐ray fluorescence (micro‐XRF) spectrometer with high spatial resolution. The spectrometer features a compact structure, combining a microfocus x‐ray source with an ellipsoidal curved crystal to form an x‐ray microprobe on the sample surface to excite the sample and produce characteristic x‐ray fluorescence. Equipped with a silicon drift detector (SDD) and a two‐dimensional sample stage, the spectrometer can perform automated non‐destructive testing of samples. We characterized the focused spot using a high‐resolution x‐ray sCMOS detector, with a size of 24.4 μm FWHM (H) × 23.9 μm FWHM (V). The spectrometer was employed for micro‐XRF scanning of a 100 mesh hexagonal copper grid superimposed on nickel foil, collecting Cu Kα and Ni Kα signals and successfully reconstructing the periodic structure of the grid. Subsequently, micro‐XRF scanning was conducted on a magnetite thin section, yielding elemental maps of Fe and Ti. The results demonstrate that the micro‐XRF spectrometer can non‐destructively obtain the spatial distribution characteristics of sample element and holds broad application prospects in geological mineral analysis, plant research, archaeological research, and semiconductor measurement.