Abstract
To interpret the interplay mechanism of dislocations associated with secondary phase (SP) particles, <111> CdZnTe crystals are annealed at isothermal and thermal gradient conditions under Cd/Zn and Te overpressure, respectively. The etching pit arrangement surrounding Te-SP is evaluated to gain an insight into the generation and multiplication of induced dislocations. It is demonstrated that Te-SP dissociation dominates the volume variation during isothermal annealing. This dissociation is enhanced under Cd/Zn overpressure due to an exothermic reaction, which results in the activation of dislocation glide and climb systems and, simultaneously, the diffusion of Tei. In turn, 'radial-shaped' dislocation rosettes and 'star-shaped' dislocation clusters appear on the {111}B surface after preferential etching. However, for thermal gradient annealing, Te-SP thermomigration predominates. The induced dislocation density is related to the Te droplet drift velocity. Meanwhile, Cd/Zn and Te overpressure could promote or slow down the migration. Interestingly, no remarkable dislocation rosettes or clusters are observed after temperature gradient annealing under Te overpressure.
Original language | English |
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Pages (from-to) | 8639-8644 |
Number of pages | 6 |
Journal | CrystEngComm |
Volume | 17 |
Issue number | 45 |
DOIs | |
State | Published - 2015 |