% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@INPROCEEDINGS{Ritz:827188,
      author       = {Ritz, Robert and Huth, Martin and Ihle, Sebastian and
                      Schmidt, Julia and Simson, Martin and Soltau, Heike and
                      Johnstone, Duncan N. and Leary, Rowan K. and Midgley, Paul
                      A. and Duchamp, Martial and Migunov, Vadim and
                      Dunin-Borkowski, Rafal and Ryll, Henning and Strüder,
                      Lothar},
      title        = {{S}canning electron diffraction using the pn{CCD}
                      ({S}){TEM} {C}amera},
      address      = {Weinheim, Germany},
      publisher    = {Wiley-VCH Verlag GmbH $\&$ Co. KGaA},
      reportid     = {FZJ-2017-01386},
      pages        = {641 - 641},
      year         = {2016},
      comment      = {European Microscopy Congress 2016: Proceedings},
      booktitle     = {European Microscopy Congress 2016:
                       Proceedings},
      abstract     = {Scanning electron diffraction (SED), performed in a (S)TEM,
                      is a powerful technique combining information in reciprocal
                      space and real space to achieve nanoscale crystal
                      cartography of materials structure. SED involves scanning a
                      focused electron beam across a specimen and recording an
                      electron diffraction pattern at each position to yield a 4D
                      dataset comprising a 2D diffraction pattern at every
                      position in the 2D scan region. Obtaining high quality data
                      depends on fast acquisition, large dynamic range, and
                      accurate recording of the location and intensity of
                      diffraction spots. Here, we present SED measurements using
                      the pnCCD (S)TEM camera taking a Ti-Fe-Mo alloy for
                      demonstration. The large number of pixels and high readout
                      speed of this camera enables the recording of high quality
                      diffraction patterns in a short acquisition time. Further,
                      using the various camera operation modes, position and
                      intensity of diffraction spots can be determined
                      precisely.The pnCCD (S)TEM camera provides fast acquisition
                      of 2D camera images using a direct detecting, radiation hard
                      pnCCD with 264x264 pixels [1]. Routinely, the readout speed
                      is 1000 frames per second (fps) and can be further increased
                      by binning and windowing. For example, with the pnCCD (S)TEM
                      camera, a 256x256 STEM dataset -- where a camera image is
                      recorded at each of the 65 536 probe positions -- can be
                      recorded in less than 70 s. The camera properties can be
                      changed by modifying the voltages applied to the pnCCD and
                      thus adjusted to the experimental needs [2]. Considering
                      scanning electron diffraction experiments, which are
                      performed at high electron beam intensities, the combination
                      of data recorded in two different camera operation modes
                      allows a comprehensive diffraction pattern analysis with
                      quantitative and spatial information. In the
                      high-charge-handling-capacity (HCHC) mode, up to 16 000
                      incident electrons per pixel per second can be processed for
                      a primary electron energy of 80 keV and a readout speed of
                      1000 fps. In the case of higher electron rates where the
                      amount of signal exceeds the charge handling capacity of the
                      affected detector pixels, signal spills over into
                      neighboring pixels. Although diffraction spots broaden, the
                      quantitative information is preserved. In the anti-blooming
                      (AB) mode, the amount of signal exceeding the charge
                      handling capacity is drained from the detector preventing an
                      overflowing of pixels. Thus, the spatial information is
                      preserved. The data can be analysed in a number of ways [3],
                      most simply by plotting the intensity of a subset of pixels
                      as a function of probe position in flexible post-experiment
                      schemes to obtain ‘virtual diffraction images’ or to
                      perform differential phase contrast analysis.Results are
                      shown (Figure 1) from a Ti(40 $at.\%)-Fe(20$ $at.\%)-Mo(40$
                      $at.\%)$ alloy from which SED data was acquired in an FEI
                      Titan G2 80-200 ChemiSTEM microscope, operated at 200 keV. A
                      diffraction pattern was recorded for each of the 512x512
                      probe positions using both HCHC and AB modes of the pnCCD
                      (S)TEM camera at a readout speed of 1000 fps. Each dataset
                      was thus acquired with a total acquisition time of less than
                      5 minutes per STEM dataset. Virtual diffraction images using
                      the AB-mode data were then formed to discriminate the two
                      phases existing in an ultra-fine lamellar microstructure [4]
                      in this Ti-Fe-Mo alloy.},
      month         = {Aug},
      date          = {2016-08-28},
      organization  = {16th European Microscopy Congress (EMC
                       2016), Lyon (France), 28 Aug 2016 - 2
                       Sep 2016},
      cin          = {PGI-5 / ER-C-1},
      cid          = {I:(DE-Juel1)PGI-5-20110106 / I:(DE-Juel1)ER-C-1-20170209},
      pnm          = {143 - Controlling Configuration-Based Phenomena (POF3-143)},
      pid          = {G:(DE-HGF)POF3-143},
      typ          = {PUB:(DE-HGF)8 / PUB:(DE-HGF)7},
      doi          = {10.1002/9783527808465.EMC2016.5224},
      url          = {https://juser.fz-juelich.de/record/827188},
}