Critical points of strained Si_1-yC_y layers on Si(001)

authored by

W. Kissinger, M. Weidner, H. J. Osten, M. Eichler

Abstract

Spectroscopic ellipsometry (SE) and electroreflectance spectroscopy (ER) measurements in the energy range of direct transitions yield information about the bandstructure. We applied both techniques to investigate the effect of carbon on the critical points of Si_1-yC_y layers grown pseudomorphically on Si(001) for 0≤y≤0.012 in the energy range between 3 and 5 eV. The critical point energies for the E₀, E₁ and E₂ transitions were determined by fitting experimental ER and SE spectra. The results of both techniques are compared. The critical point energy E₁ , obtained by fitting the line shape of the second derivative of the dielectric function measured by SE, increases with higher carbon content whereas the E₂ critical point energy decreases. ER measurements show the same tendency, but can resolve also the E₀ transition that decreases slightly for higher carbon contents. The line broadening of the Si_1-yC_y layers depends much stronger on the fraction of alloying atoms compared to the Si_1-xGe_x system.

External Organisation(s)

Leibniz Institute for High Performance Microelectronics (IHP)

Type

Article

Journal

Solid State Phenomena

Volume

47-48

Pages

523-528

No. of pages

6

ISSN

1012-0394

Publication date

1996

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Atomic and Molecular Physics, and Optics, General Materials Science, Condensed Matter Physics