A new Particle-Induced X-ray Emission set-up for laterally resolved analysis over wide areas

The recently installed and unique PIXE (particle-induced X-ray emission) set-up at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) is mainly dedicated to applications for a detailed overview of elemental composition over large sample areas within a short time even at trace level. The so-called High-Speed-PIXE (HS-PIXE), a combination of a pnCCD based pixel-detector with polycapillary X-ray optics, offers simultaneous imaging of sample areas up to 12 x 12 mm² with a lateral resolution better than 100 µm. Each of the 264 x 264 individual pixels detects X-ray photons in an energy range from 2 keV to 20 keV with an energy resolution of 156 eV (@Mn-Kα). A high precision sample manipulator offers the inspection of areas up to 250 x 250 mm². During first experiments the lateral resolution could be determined to (76 ± 23) µm using a sample of well-known sharp-edged chromium patterns. Trace element analysis has been performed using a geological sample, a tin ore, with an average Ta-concentration below 0.1 at.%. Fine-zoned structures became visible in the Ta-Lα intensity map within only 45 min. The High-Speed-PIXE closes a gap in the analytic process flow chain especially for geoanalytical characterisations. It is a unique and fast detection system to identify areas of interest in comparably short time at large-area scale for further analysis.