Raman study of Si-Ge intermixing in Ge quantum rings and dots

V. I. Mashanov, H. H. Cheng, C. T. Chia, Y. H. Chang

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

The Ge/Si (1 0 0) nanostructures have been studied by atomic force microscopy (AFM) and Micro Raman optical spectroscopy. Two layers of Ge of total thickness 0.75 nm and Si cap with thickness 2.5 nm were deposited by the method of molecular beam epitaxy at the temperature range 640-700°C. AFM shows both quantum dots and ring-shape Ge nanostructures. From the analysis of the intensity and energy shift of the Raman signal we have found that the average concentration of Ge decreases considerably from 44% to 27%, when the growth temperature increases, whereas the degree of strain relaxation remains roughly the same. This allows us to conclude that intermixing is a dominating mechanism for strain relaxation in processes of transformation of Ge quantum dots to quantum rings.

Original languageEnglish
Pages (from-to)531-536
Number of pages6
JournalPhysica E: Low-Dimensional Systems and Nanostructures
Volume28
Issue number4
DOIs
Publication statusPublished - 2005 Sep 1

Keywords

  • Germanium
  • Quantum dots
  • Quantum rings
  • Raman scattering

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Raman study of Si-Ge intermixing in Ge quantum rings and dots'. Together they form a unique fingerprint.

  • Cite this