title: X-ray characterization of Ge dots epitaxially grown on nanostructured Si islands on silicon-on-insulator substrates.
abstract: 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.
authors.affiliation: IHP , Im Technologiepark 25, Frankfurt (Oder), 15236, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Zaumseil
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Kozlowski
authors.forename: Yuji
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Markus Andreas
authors.initials: MA
authors.lastname: Schubert
authors.forename: Thomas
authors.initials: T
authors.lastname: Schroeder
keywords: Ge heteroepitaxy; grazing-incidence X-ray diffraction; nanostructured Si; silicon-on-insulator (SOI) substrates; transmission electron microscopy (TEM)
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