X-ray characterization of Ge dots epitaxially grown on nanostructured Si islands on silicon-on-insulator substrates

• Published in: Journal of applied crystallography Vol. 46; no. 4; pp. 868 - 873
• Main Authors: Zaumseil, Peter, Kozlowski, Grzegorz, Yamamoto, Yuji, Schubert, Markus Andreas, Schroeder, Thomas
• Format: Journal Article
• Language: English
• Published: 5 Abbey Square, Chester, Cheshire CH1 2HU, England International Union of Crystallography 01.08.2013; Blackwell Publishing Ltd
• Subjects: Crystallography; Diffraction; Ge heteroepitaxy; Germanium; grazing-incidence X-ray diffraction; Islands; Materials science; Nanocomposites; Nanomaterials; Nanostructure; Nanostructured materials; nanostructured Si; Semiconductors; Silicon substrates; silicon-on-insulator (SOI) substrates; Strain; Substrates; transmission electron microscopy (TEM); X-Ray Diffraction and Imaging; transmission electron microscopy (TEM); nanostructured Si; grazing-incidence X-ray diffraction; Ge heteroepitaxy; silicon-on-insulator (SOI) substrates
• ISSN: 1600-5767; 0021-8898; 1600-5767
• DOI: 10.1107/S0021889813003518

On the way to integrate lattice mismatched semiconductors on Si(001), the Ge/Si heterosystem was used as a case study for the concept of compliant substrate effects that offer the vision to be able to integrate defect‐free alternative semiconductor structures on Si. Ge nanoclusters were selectively grown by chemical vapour deposition on Si nano‐islands on silicon‐on‐insulator (SOI) substrates. The strain states of Ge clusters and Si islands were measured by grazing‐incidence diffraction using a laboratory‐based X‐ray diffraction technique. A tensile strain of up to 0.5% was detected in the Si islands after direct Ge deposition. Using a thin (∼10 nm) SiGe buffer layer between Si and Ge the tensile strain increases to 1.8%. Transmission electron microscopy studies confirm the absence of a regular grid of misfit dislocations in such structures. This clear experimental evidence for the compliance of Si nano‐islands on SOI substrates opens a new integration concept that is not only limited to Ge but also extendable to semiconductors like III–V and II–VI materials.