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Information × Registration Number 0208U006699, 0107U008230 , R & D reports Title Nanozond and optical studies of the effect of struturized metallic layers on the emission and scattering of light in semiconductor structures. popup.stage_title Head Valakh Mykhaylo Yakovych, Доктор фізико-математичних наук Registration Date 19-12-2008 Organization Institute of Semiconductor Physics of NAS of Ukraine popup.description2 The formation of structures promising for production of the SERS (surface-enhanced Raman scattering)-substrates was performed by two different methods. The first one is the formation of silver nanoislands on the surface of bulk silicon by a thermal deposition of the silver layer in vacuum with the following thermal annealing of the film. The temperature, duration and the atmosphere at the annealing are the key parameters which determine the film morphology. Within the second method the formation of the nanostructured silver layer was made on the surface of porous silicon by photoreduction from the AgNO3 solution. The efficiency of the enhancement was estimated by measuring the Raman spectra of the analyte molecule adsorbed on the silver surface. The technological conditions which provide the silver nanostructures on bulk and porous silicon substrates with highest enhancement of the Raman signal were studied. The investigations made allow a relation to be established between the morphology of the surface and its enhancement efficiency. It is found that the enhancement is stronger for the porous substrates wit the macropores and cracks of micrometer size on the surface, because such morphology allows more silver clusters of a large enough size to be formed than at a flat surface. An interesting result is obtaining of a film of closely-packed silver nanocrystals at high concentration of HF in the etching solution. Due to the small distance between the silver particles, a high concentration of electric field is achieved in this spots, where the SERS signal extremely high. For silicon-germanium quantum dots (QDs) embedded into silicon matrix, an enhancement of the Raman scattering on the phonons localized inside the quantum dots is achieved by the field of plasmon in the silver nanoislands deposited onto the top of the QD structure.5635 Product Description popup.authors popup.nrat_date 2020-04-02 Close