Colloidal nanocrystals integrated in epitaxial nanostructures: structural and optical properties

✍ Scribed by Ch. Arens; N. Roussau; D. Schikora; K. Lischka; O. Schöps; E. Herz; U. Woggon; D. Litvinov; D. Gerthsen; M. V. Artemyev

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 236 KB
• Volume: 3
• Category: Article
• ISSN: 1862-6351
• DOI: 10.1002/pssc.200564630

✦ Synopsis

Abstract

Using the well established MBE process, we introduced colloidal nanocrystals (NCs) into monocrystalline semiconductor layers. CdSe nanorods (NRs) and CdSe(ZnS) core‐shell nanodots (NDs) with radii R between 2 and 4 nm on a ZnSe surface are capped by thin (d ∼ 2__R__ ) and thick (d > 2__R__ ) MBE‐grown ZnSe layers of a thickness d . This new growth technique does not rely on strain like the Stranski‐Krastanow growth of CdSe/ZnSe quantum dot layers, and thus offers additional degrees of freedom for choosing the NC composition, shape and size. In‐ and ex‐ situ characterisations of the samples are showing a ZnSe cap layer of high crystalline quality. After the growth of the cap layer the dots preserve their shape and emission spectrum. High‐resolution transmission electron microscope images show the direct connection of the NCs crystal lattice to the crystal lattices of the ZnSe buffer and the epitaxially grown cap layer. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)