Optical properties of silicon nanowire arrays formed by metal-assisted chemical etching: evidences for light localization effect
| Autor: | Dmitry Petrov, Liubov A. Osminkina, Vladimir Sivakov, Florian Talkenberg, Vladimir S Marshov, Victor Yu. Timoshenko, K. A. Gonchar, Konstantin V Bunkov, Leonid A. Golovan |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Raman scattering
Materials science Nanotechnology 02 engineering and technology Substrate (electronics) 01 natural sciences Light scattering Light localization symbols.namesake chemistry.chemical_compound Silicon nanowires Materials Science(all) 0103 physical sciences Transmittance General Materials Science Crystalline silicon 010302 applied physics Nano Express Scattering business.industry Black silicon 021001 nanoscience & nanotechnology Condensed Matter Physics Isotropic etching chemistry symbols Optoelectronics 0210 nano-technology business |
| Zdroj: | Nanoscale Research Letters |
| ISSN: | 1556-276X |
| DOI: | 10.1186/1556-276x-7-524 |
| Popis: | We study the structure and optical properties of arrays of silicon nanowires (SiNWs) with a mean diameter of approximately 100 nm and length of about 1-25 μm formed on crystalline silicon (c-Si) substrates by using metal-assisted chemical etching in hydrofluoric acid solutions. In the middle infrared spectral region, the reflectance and transmittance of the formed SiNW arrays can be described in the framework of an effective medium with the effective refractive index of about 1.3 (porosity, approximately 75%), while a strong light scattering for wavelength of 0.3 ÷ 1 μm results in a decrease of the total reflectance of 1%-5%, which cannot be described in the effective medium approximation. The Raman scattering intensity under excitation at approximately 1 μm increases strongly in the sample with SiNWs in comparison with that in c-Si substrate. This effect is related to an increase of the light-matter interaction time due to the strong scattering of the excitation light in SiNW array. The prepared SiNWs are discussed as a kind of 'black silicon', which can be formed in a large scale and can be used for photonic applications as well as in molecular sensing. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink