Affiliation: | a Department of Electrical and Electronic Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK b Physics Department E16, Technische Universitat Muenchen, James-Frank-Strasse, D-85747 Garching, Germany |
Abstract: | The results of Raman scattering and X-ray diffraction studies of thick, free-standing, porous Si layers with thickness up to 500 μm are presented. The Raman scattering spectra have a distinctive difference from previous data for porous Si films on Si substrate and for thin, free-standing, porous Si layers. The experimental data can be explained by a modified phonon confinement model that accounts for a comprehensive strained Si nanocrystal. The comprehensive strain is a tensile one, and the value of stress can be up to 3 GPa. This interpretation is supported by data of X-ray diffraction measurements. |