High‐resolution transmission electron microscopy of structural changes at and near surfaces of ZnTe crystals
Autor: | M. Avalos‐Borja, X. G. Ning, Hengqiang Ye |
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Rok vydání: | 1996 |
Předmět: |
Materials science
Oxide Analytical chemistry General Physics and Astronomy chemistry.chemical_element Evaporation (deposition) Amorphous solid chemistry.chemical_compound Crystallography chemistry Transmission electron microscopy Electron beam processing High-resolution transmission electron microscopy Tellurium Superstructure (condensed matter) |
Zdroj: | Journal of Applied Physics. 79:125-128 |
ISSN: | 1089-7550 0021-8979 |
DOI: | 10.1063/1.360919 |
Popis: | Structural changes on and near surfaces of ZnTe crystals were observed by the surface profile imaging method in a high‐resolution transmission electron microscope (HRTEM) with 200 kV accelerating voltage. It was found that ZnO particles form under electron irradiation on surfaces originally covered with a thin amorphous layer. For amorphous coverages thicker than about 7 nm, ZnO particles were not observed. Under the ZnO particles, 2×1 and 2×2 superstructures (about 10 nm in size) were often found in the ZnTe matrix. These superstructures can be described as a metastable Zn2Te3 having a structure similar to the ordered Ga2Te3 structure. This change can be accomplished by considering the diffusion of zinc from the ZnTe matrix to the surface to form the oxide and evaporation of tellurium out of the surface, leaving behind a matrix with an altered stoichiometry. The HRTEM computer‐simulated images for the proposed Zn2Te3 superstructure matched very well the experimental images. The 2×1 and 2×2 superstructure... |
Databáze: | OpenAIRE |
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