Nanoscale Precipitates in Single Te Inclusions in Cd 0.9 Zn 0.1 Te Crystal

The complexity of phenomena governing alloy crystal growth can be unraveled by examining the three-dimensional atomic-level distribution of elements and impurities incorporated during growth. These species act as fingerprints, revealing the thermodynamic constraints that shape material structure and composition. Herein, we combine transmission electron microscopy and atom probe tomography to investigate single tellurium (Te) inclusions within cadmium zinc telluride (CZT) monocrystals. These analyses uncover nanoscale precipitates embedded within Te inclusions, consisting of CZT nanocrystals with a Zn content of 1.5 at. %. Surrounding these precipitates, a ∼10 nm-thick shell, enriched with copper and indium impurities, is observed. In addition, traces of sodium and sulfur are detected within the nanocrystals. These findings provide direct evidence of the complex segregation and precipitation processes occurring during CZT crystal growth, reflecting the interplay between thermodynamic driving forces and kinetic constraints that govern solute redistribution. The resulting insights contribute to a deeper understanding of impurity behavior and phase separation mechanisms in CZT alloys.