Combining Borrmann and weak-beam diffraction images to study defects in a high-quality CdTe(Zn) crystal

T. Journot (1) , D. Brellier (1) , P. Ballet (1) , T. N. Tran Thi Caliste (2) , E. Gout (1) , D. Collonge (1) , J. Baruchel (2)

1 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
2 ESRF - European Synchroton Radiation Facility [Grenoble]

In this work, synchrotron radiation rocking curve imaging (RCI) is used to visualize and characterize dislocations and second-phase defects in a highly perfect and absorbing CdTe(Zn) crystal. This technique requires recording a series of Bragg diffracted images along the rocking curve to produce maps of the ‘local’ integrated intensity, full width at half-maximum and peak position. The diffraction conditions of the reported experiment are such that anomalous transmission (Borrmann effect) is a crucial ingredient for the formation of the image of the defects. The images recorded and maps produced allow the investigation of a series of topics that, to the authors’ knowledge, have not been previously studied. The first of these topics is the variation of the position and width of the Borrmann image of a defect when sitting on the peak and on the flanks of the diffraction curve. The second topic is the way Borrmann images show up on the usual RCI maps. The final topic is the combination of Borrmann and weak-beam images to infer the depth of the defect within the crystal.

Keywords: Bragg diffraction topography; rocking curve imaging; Borrmann effect; weakbeam images; CdTe(Zn) crystals; dislocations

Domains: Material chemistry

T. Journot, D. Brellier, P. Ballet, T. N. Tran Thi Caliste, E. Gout, et al.. Combining Borrmann and weak-beam diffraction images to study defects in a high-quality CdTe(Zn) crystal. Journal of Applied Crystallography, 2023, 56, pp.401 - 408. ⟨10.1107/s1600576723000377⟩. ⟨cea-04057392⟩