Three-dimensional atom-by-atom mapping of nanoscale precipitates in single Te inclusions in Cd0.9Zn0.1Te crystal

TL;DR

This study employs advanced microscopy techniques to map the 3D atomic distribution in Te inclusions within CZT crystals, revealing nanoscale precipitates, impurity segregation, and phase separation mechanisms crucial for improving crystal growth.

Contribution

It provides the first detailed 3D atomic-level mapping of Te inclusions in CZT, uncovering nanoscale precipitates and impurity distributions that inform growth optimization.

Findings

Nanoscale CZT nanocrystals with 1.5 at.% Zn inside Te inclusions.

A 10 nm shell enriched with Cu and In around precipitates.

Detection of Na and S traces within nanocrystals.

Abstract

The complexity and richness 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 atomic fingerprints, revealing the thermodynamic constraints that shape material structure and composition. Herein, we combine transmission electron microscopy and atom probe of tellurium (Te) inclusions within cadmium zinc telluride (CZT) single crystals. The correlative analysis uncovers nanoscale precipitates embedded within Te inclusions, consisting of CZT nanocrystals with a Zn content of 1.5 at.%. Surrounding these precipitates, an around 10 nm-thick shell is observed, enriched with copper and indium impurities. 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 of 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. This work establishes a framework for modeling and optimization of growth strategies of higher-quality CZT crystals for next-generation infrared and radiation detection technologies.