IONIZATION METHOD OF NEEDLE-LIKE SAMPLE SURFACE LAYER BY USING BOTH ULTRASHORT PULSE LASER CONVERGENCE AND HIGH VOLTAGE APPLICATION, AND ANALYTICAL METHOD OF NEEDLE-LIKE SAMPLE SURFACE LAYER USING IT
PROBLEM TO BE SOLVED: To solve a problem that, for the conventional ionization of a needle-like sample, a pulse high voltage is applied to a needlepoint thereof or it is irradiated with a nanosecond laser, however, the needle-like sample is broken or a resolution is degraded by a temperature rise by heating in a three-dimensional atom probe electric field microscope and the analysis of a semiconductor or an insulation material is extremely difficult when such an ionization method is used. SOLUTION: This ionization method allows the analysis of a three-dimensional distribution of elements without breaking a needle-like sample having residual stress inside, and not only enhances resolution but also allows the analysis of a semiconductor or an insulation material by sequentially ionizing and removing atoms on the surface layer of the needle-like sample by converging an ultrashort pulse laser beam on the needlepoint of the needle-like sample having a curvature radius substantially smaller than a wavelength applied with the high voltage below a threshold generated by field evaporation. COPYRIGHT: (C)2006,JPO&NCIPI
