The Effect Of C~+ Implantation On Photoluminescent Properties Of Si Nanocrystals

In the last decade, the search for efficient luminescent structures based on Si technology has grown to a rapid pace. In particular, the research has been focused on the growth and optimization of Si nanostructure embedded in silicon oxide. Due to the quantum confinement effect, the luminescence band of Si nanocrystals (Nc-Si) located in the IR to red. A quiet quantity hanging bonds between Si and silicon oxide can decrease the luminescence efficiency of Nc-Si, so it is necessary to find a method to improve the luminescence by decrease the defect. Silicon carbide is one of the wide gap semiconductors, due to the broad band-gap (2.2-3.3ev) character, it can be used to synthesis materials of blue,green and violet-emitting. Therefore, we expect to realize the high efficiency and whole visible luminescence by the method of implanting C⁺ into Si nanocrystals that embedded in silicon oxide.SiO/SiO₂ superlattices samples were prepared on Si substrates by reactive evaporation of SiO powder in vacuum or an oxygen atmosphere. The samples were annealed in nitrogen atmosphere at high temperature subsequently. And then, these samples with formed Si nanocrystals were implanted with C⁺ to dose of 1.0×10¹⁴/cm²,1.0×10¹⁵/cm²,1×10¹⁶/cm²,5×10¹⁶/cm²,1×10¹⁷/cm²,2×10¹⁷/cm²,3×10¹⁷/cm²respectively, and then the implanted samples were re-annealing in nitrogen atmosphere at different temperature. By PL spectra and FTIR spectra measurement, the luminescence of Nc-Si affected by different implanted dose and re-annealing temperature were investigated, and the luminescence mechanism of the samples with low and high implanted dose were studied.