Investigation of an oxide layer by femtosecond-laser-assisted atom probe tomography

In this letter, we report results obtained from the atom-probe tomography (APT) analysis of an oxide layer developed on a pure iron specimen under low pressure of oxygen. These specimens are generally fragile, and hard to analyze in APT. Here we show that by the use of femtosecond laser pulses, the oxide layer could be field evaporated atom by atom allowing its chemical identification at the atomic scale. The evidence of iron atomic planes through the whole oxide layer suggests that oxygen atoms diffuse though the oxide layer during the first stages of the oxidation process. (c) 2006 American Institute of Physics.