In the present study, several different multiple-layered Ge/Si (001) QD structures with the final QD layer uncapped have been fabricated using gas source molecular beam epitaxy (GSMBE). The different characterisation techniques, including atomic force microscopy, diffraction-contrast transmission electron microscopy, high-resolution lattice imageing, analytical electron microscopy, and electron tomography, have been applied to characterise the morphology, structure and chemistry of both surface and buried QDs. The size, the shape and the number density of Ge islands show drastic changes when altering parameters such as growth temperature, Ge coverage and Si spacer layer thickness within Ge/Si multilayers. The atomic scale details obtained by HRTEM are combined with the results of field-emission gun scanning transmission electron microscopy (FEG-STEM), electron tomography to provide information on the structure of the QDs. All these structure information about QDs are discussed in relating to GSMBE growth conditions.
|Number of pages||4|
|Journal||Institute of Physics Conference Series|
|Publication status||Published - 19 Oct 2004|
|Event||Electron Microscopy and Analysis 2003 - Proceedings of the Institute of Physics Electron Microscopy and Analysis Group Conference - Oxford, United Kingdom|
Duration: 3 Sep 2003 → 5 Sep 2003