In-situ observation of non-hemispherical tip shape formation during laser-assisted atom probe tomography
2011 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 109, no 10, 104909- p.Article in journal (Refereed) Published
It is shown by SEM imaging of the tip and by observing the emission pattern of the evaporated atoms that laser assisted evaporation in an atom probe can lead to nonhemispherical tip shapes and time-dependent nonuniform emission. We have investigated this nonuniformity by observing the change in field of view when using laser wavelengths of 515 nm and 343 nm on silicon. The change is monitored in situ by 0.5 nm thick silicon oxide. We demonstrate that the field of view can easily be changed by more than 10 nm and that the apparent oxide layer thickness can deviate substantially from its correct value. The dependence of the tip shape deformations and the reconstruction artifacts on the laser wavelength are explained through simulations of the laser-tip interaction and nonhomogeneous heating effects.
Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2011. Vol. 109, no 10, 104909- p.
deformation, elemental semiconductors, evaporation, laser beam applications, scanning electron microscopy, silicon, silicon compounds, tomography
Research subject SRA - ICT
IdentifiersURN: urn:nbn:se:kth:diva-46342DOI: 10.1063/1.3592339ISI: 000292115900154OAI: oai:DiVA.org:kth-46342DiVA: diva2:453794
QC 201111032011-11-032011-11-032011-12-14Bibliographically approved