Modified growth of Ge quantum dots using C 2 H 4 mediation by ultra-high vacuum chemical vapor deposition

S. W. Lee, P. S. Chen, S. L. Cheng, M. H. Lee, H. T. Chang, C. H. Lee, C. W. Liu

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

C 2 H 4 mediations were used to modify the Stranski-Krastanow growth mode of Ge dots on Si(0 0 1) at 550 °C by ultra-high vacuum chemical vapor deposition. With appropriate C 2 H 4 -mediation to modify the Si surface, the elongated Ge hut clusters can be transformed to highly uniform Ge domes with a high Ge composition at the core. These C 2 H 4 -mediated Ge dots, almost bounded by {1 1 3} facets, have an average diameter and height of 55 and 9 nm, respectively. We propose two major mechanisms to depict the formation of these C 2 H 4 -mediated Ge dots: (i) an almost hydrogen-passivated Si surface to limit the nucleation sites for dot formation, and (ii) the incorporation of Ge atoms, repelled by the C-rich areas, into the existing Ge dots. This work provides a useful scheme to tune the topography of Ge dots in an UHV/CVD condition for possible optoelectronic applications.

Original languageEnglish
Pages (from-to)6261-6264
Number of pages4
JournalApplied Surface Science
Volume254
Issue number19
DOIs
Publication statusPublished - 2008 Jul 30

    Fingerprint

Keywords

  • Ge
  • Quantum dot
  • Self-assembled
  • UHV/CVD

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics
  • Physics and Astronomy(all)
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films

Cite this