HEAVY-ION MICROPROBE FOR PIXE ANALYSIS OF IRON

Heavy ion microprobes such as a few MeV Si, Ni beams with a beam size of a few microns were applied for micro-analysis of iron using PIXE. S tainless steel foil or iron substrates were analyzed by 5 MeV Ni3+, Si 3+ and 2 MeV proton beams. The X-ray spectra showed that the X-ray emi ssion strongly depended on the incident ion species. It shows that the Si probe has a higher sensitivity to the Fe-L X-rays than that of the proton beam. On the contrary, the proton has higher sensitivity to th e Fe-K X-rays than the Si beam. The Ni probe has more higher sensitivi ty for both energies of X-rays than the other probes. It is considered that molecular orbital effects took place between Fe and Ni atoms due to very close level matching. The energy shift and broadening due to multi-ionization were observed in the Fe-L X-ray spectra of the Si and Ni impacts.