Chapters authored
Nanostructured Si/SiO2 Quantum Wells
The motivation for developing light-emitting devices on an indirect transition semiconductor such as silicon has been widely discussed for Si/SiO2 nanostructures. In this chapter, we report on the fabrication of Si/SiO2 quantum-confined amorphous nanostructured films and their optical properties. The Si/SiO2 nanostructures comprising amorphous Si, SiO2, and Si/SiO2 multilayers are grown using ultrahigh vacuum radio frequency magnetron sputtering. Optical absorption coefficients of the Si/SiO2 nanostructures are evaluated with regard to tentative integrated Si thicknesses. Optical energy band gaps of the Si/SiO2 multilayer films are in accordance with the effective mass theory and described as E0 = 1.61 + 0.75d−2 eV at the Si layer-integrated thicknesses ranging from 0.5 to 6 nm. Quantum confinement effects in the Si/SiO2 nanostructures are inferred from optical transmittance and reflectance spectra. The rapid-thermal-annealed Si/SiO2 multilayer films demonstrate the intensified photoluminescence at ~1.45 eV due to the formation of nanocrystalline silicon. The temperature dependence of the nanocrystalline luminescence intensity shows the nonmonotonous behavior which is interpreted invoking the Kapoor model.
Part of the book: Nanostructures in Energy Generation, Transmission and Storage