FIB Induced X-rays (FIBIX) Using 30 keV Ga+ Ions

Abstract

FIB induced X-rays (FIBIX) using a 30 keV Ga+ primary ion beam were collecting using EDS and WDS techniques for conducting samples, YBCO, Al, Cu, ZrB2, and Mo. FIBIX X-ray cross sections are largest for the light element materials, presumably due to momentum transfer from the primary ions to the target atoms and consistent with molecular orbital generation processes. The Ga+ Bremsstrahlung is largest in the low energy X-ray range, less than ∼1 keV, but is essentially nonexistent at higher energies. Thus, characteristic X-ray peaks greater than ∼1 keV are easily identifiable and statistically significant even at low count rates. The large FIBIX counts observed at less than 1 keV are a combination of Bremstrahhlung and characteristic low energy X-rays from light elements, as confirmed by high energy resolution WDS measurements. Low energy X-rays from heavy element targets are difficult to detect using FIBIX, again presumably due to a small amount of momentum transfer to the target atoms.