Open AccessX‐ray diffraction imaging of metal–oxide epitaxial tunnel junctions made by optical lithography: use of focused and unfocused X‐ray beams
Author(s) -
Mocuta Cristian,
Barbier Antoine,
Stanescu Stefan,
Matzen Sylvia,
Moussy JeanBaptiste,
Ziegler Eric
Publication year - 2013
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s090904951204856x
Subject(s) - optics , diffraction , raster scan , materials science , lithography , curvature , raster graphics , x ray , perpendicular , physics , geometry , mathematics , artificial intelligence , computer science
X‐ray diffraction techniques are used in imaging mode in order to characterize micrometre‐sized objects. The samples used as models are metal–oxide tunnel junctions made by optical lithography, with lateral sizes ranging from 150 µm down to 10 µm and various shapes: discs, squares and rectangles. Two approaches are described and compared, both using diffraction contrast: full‐field imaging (topography) and raster imaging (scanning probe) using a micrometre‐sized focused X‐ray beam. It is shown that the full‐field image gives access to macroscopic distortions ( e.g. sample bending), while the local distortions, at the micrometre scale ( e.g. tilts of the crystalline planes in the vicinity of the junction edges), can be accurately characterized only using focused X‐ray beams. These local defects are dependent on the junction shape and larger by one order of magnitude than the macroscopic curvature of the sample.