Segregation-enhanced etching of Cd during Zn deposition on CdSe quantum dots
نویسندگان
چکیده
CdSe/ZnSe quantum structures grown on GaAs~001! by molecular-beam epitaxy were systematically investigated by high-resolution x-ray diffraction and high-resolution transmission-electron microscopy. Half of the initial Cd deposit redesorbs when migration-enhanced epitaxy is used instead of conventional molecular-beam epitaxy for the overgrowth of the CdSe by ZnSe. This result is explained by a segregation model accounting for an enhanced redesorption of Cd due to Cd segregation and replacement of Cd by Zn in the topmost surface layers. The observed intermixing of CdSe/ZnSe can be explained by this model.
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