APPLICATION OF A MEV NICKEL ION-BEAM FOR PIXE ANALYSIS OF IRON NEAR-THE-SURFACE OF A SILICON-WAFER

A heavy ion (5.5 MeV Ni3+) beam was applied for PIXE (particle induced X-ray emission) analysis of iron implanted into a silicon wafer with energy of 343 keV. The implanted fluences ranged from 1 X 10(13) to 7. 3 X 10(15) ions/cm(2). In order to compare with conventional PIXE anal ysis by light ions, a 2 MeV proton beam was also employed. It was foun d that the nickel probe has a few times larger cross sections for Fe K alpha. X-ray production than the proton, while the background level a round the Fe K alpha X-ray energy was a few tens times less than in th e case of the proton. It was concluded that the detection limit of iro n near the surface of the silicon wafer was improved very much by usin g the MeV nickel probe. This is because molecular orbital effects took place between Fe and Ni atoms due to very close level matching and re latively low energy of incident nickel (similar to 0.1 MeV/amu) that i nduced low background levels.