Ultrahigh-Resolution X-ray Tomography

See allHide authors and affiliations

Science  18 Nov 1994:
Vol. 266, Issue 5188, pp. 1213-1215
DOI: 10.1126/science.266.5188.1213


Ultrahigh-resolution three-dimensional images of a microscopic test object were made with soft x-rays collected with a scanning transmission x-ray microscope. The test object consisted of two different patterns of gold bars on silicon nitride windows that were separated by ∼5 micrometers. Depth resolution comparable to the transverse resolution was achieved by recording nine two-dimensional images of the object at angles between –50 and +55 degrees with respect to the beam axis. The projections were then combined tomographically to form a three-dimensional image by means of an algorithm using an algebraic reconstruction technique. A transverse resolution of ∼1000 angstroms was observed. Artifacts in the reconstruction limited the overall depth resolution to ∼6000 angstroms; however, some features were clearly reconstructed with a depth resolution of ∼1000 angstroms.