Raman scattering study on pristine and oxidized n-type porous silicon

• Published in: Physica. B, Condensed matter Vol. 411; pp. 77 - 80
• Main Authors: Zhong, Furu, JIA, Zhen-hong
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.02.2013; Elsevier
• Subjects: Condensed matter; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Crystal structure; Exact sciences and technology; Nanocrystals; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Oxidation; Physics; Polystyrene resins; Porosity; Porous silicon; Raman; Scanning electron microscope (SEM); Silicon; Visible and ultraviolet spectra; Raman; Oxidation; Scanning electron microscope (SEM); Porous silicon; Line intensity; Scanning electron microscopy; Raman spectra; Hydrogen bonds; Porous materials; Silicon; Passivation
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2012.09.061

We have investigated the effects of oxidation on Raman spectra of porous silicon (PS). Many Si–H x bonds were indicated in as-anodized PS. Compared to crystalline silicon, the background in the spectrum was stronger which indicates that the PS surface was rough due to the presence of pores. When oxidation was performed, the Raman spectrum revealed the presence of nanocrystalline silicon in freshly prepared PS whose diameter was around 5.22nm. The Raman analysis showed that the peak intensities sharply decrease after oxidation compared to the as-prepared because the bonds of Si–H x on the PS surface are greatly reduced after oxidation. The oxidation of PS by thermal oxidation is complete; therefore, thermal oxidation is very well suited for a passivation of PS films.