Spectroscopic ellipsometry and band structure of Si1-yCy alloys grown pseudomorphically on Si (001)

Stefan Zollner, Craig M. Herzinger, John A. Woollam, Subramanian S. Iyer, Adrian P. Powell, Karl Eberl

Research output: Contribution to journalConference article

1 Scopus citations

Abstract

We have measured the dielectric functions of three Si1-yCy alloys layers (y ≤ 1.4%) grown pseudomorphically on Si (001) substrates using molecular beam epitaxy at low temperatures. From the numerical derivatives of the measured spectra, we determine the critical point energies E0′ and E1 as a function of y (y ≤ 1.4%) using a comparison with analytical line shapes and analyze these energies in terms of the expected shifts and splittings due to negative hydrostatic pressure, shear stress, and alloying. Our data agree well with the calculated shifts for E1, but the E0′ energies are lower than expected. We discuss our results in comparison with recent tight-binding molecular dynamics simulations by Demkov and Sankey (Phys. Rev. B 48, 2207, 1993) predicting a total breakdown of the virtual-crystal approximation for such alloys.

Original languageEnglish (US)
Pages (from-to)205-210
Number of pages6
JournalMaterials Research Society Symposium - Proceedings
Volume379
StatePublished - Dec 1 1995
EventProceedings of the 1995 MRS Spring Meeting - San Francisco, CA, USA
Duration: Apr 17 1995Apr 20 1995

    Fingerprint

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this