Drift correction of the analyzed area during the study of the lateral elemental composition distribution in single semiconductor nanostructures by scanning Auger microscopy

Abstract

The main difficulty in obtaining the lateral elemental composition distribution maps of the semiconductor nanostructures by Scanning Auger Microscopy is the thermal drift of the analyzed area, arising from its local heating with the electron probe and subsequent shift. Therefore, the main goal of the study was the development of the effective thermal drift correction procedure. The measurements were carried out on GeSi/Si nanoislands obtained with molecular beam epitaxy by means of Ge deposition on Si(100) substrate. Use of the thermal drift correction procedure made it possible to get the lateral elemental composition distribution maps of Si and Ge for various types of GeSi/Si nanoislands. The presence of the germanium core and silicon shell in both the dome GeSi/Si nanoislands and pyramid ones was established. In the authors’ opinion, this type of elemental distribution is a result of the completeness of the interdiffusion processes course in the island/wetting layer/substrate system, which play the key role in the nucleation, evolution and growth of GeSi/Si nanoislands. The proposed procedure of the thermal drift correction of the analyzed area allows direct determination of the lateral composition distribution of the GeSi/Si nanoislands with the size of the structural elements down to 10 nm.