Size distribution and optical properties of self-assembled Ge on Si

L. Vescan, M. Goryll, T. Stoica, P. Gartner, K. Grimm, O. Chretien, E. Mateeva, C. Dieker, B. Holländer

Research output: Contribution to journalArticlepeer-review

23 Scopus citations


The distribution of Ge islands is analyzed in order to understand their optical behaviour. The Ge islands described in this paper were deposited by low-pressure chemical vapour deposition at relatively high temperature (700 °C), therefore the diffusion length of adatoms is high (approximately 100 μm) and thus, not the limiting factor for nucleation. By changing the deposition time and the coverage, square-based pyramids, domes and relaxed domes are nucleated. Mainly domes emit light, the emission being in the wavelength range 1.38-1.55 μm. When pyramids or relaxed domes are present, the photoluminescence broadens and decreases in intensity. The electroluminescence of vertically correlated islands increases with the number of layers, i.e. with the number of islands. The nucleation of islands on patterned (001) Si is changed when the deposition is performed on Si mesas with high index facets. The size distribution becomes narrower when the mesa size is decreased. An intermixing of up to 40% Si in the 2D layer was determined from photoluminescence data. PIN diodes fabricated on patterned wafers show an area-dependent electroluminecence related to a different microstructure of islands on large and small mesas. Finally, the lateral ordering on {hkl} facets is discussed.

Original languageEnglish (US)
Pages (from-to)423-432
Number of pages10
JournalApplied Physics A: Materials Science and Processing
Issue number4
StatePublished - Oct 2000
Externally publishedYes

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)


Dive into the research topics of 'Size distribution and optical properties of self-assembled Ge on Si'. Together they form a unique fingerprint.

Cite this