Brillouin light scattering from porous silicon films and multilayers

✍ Scribed by Andrews, G. T. ;Polomska, A. M. ;Vazsonyi, E. ;Volk, J.

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 455 KB
• Volume: 204
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200674344

✦ Synopsis

Abstract

Porous silicon films and multilayers were studied using Brillouin spectroscopy. Acoustic wave velocities and elastic constants were determined for films with porosity ∼0.60 formed from p^–^, p^+^ and n^+^ crystalline silicon. The velocities and elastic constants depend on the pore/crystallite geometry and morphology. Porous silicon multilayers were fabricated from (100) p^+^ crystalline silicon. For a multilayer with 250 nm layer thickness and layer porosity sequence of 0.45/0.65/0.45/0.65/0.45, the Rayleigh surface phonon velocity was found to be 2850 m/s. The origin(s) of other peaks in the multilayer spectra are unknown but it is unlikely that they are surface modes because their shift(s) are independent of incident angle. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)