Photoluminescent spectrum and dynamics ofSi+-ion-implanted and thermally annealedSiO2

Abstract

We have experimentally studied the photoluminescent ͑PL͒ properties of Si clusters in fused silica matrices. Si clusters in the SiO 2 matrices were fabricated by Si ϩ -ion implantation ͑200 keV, 2ϫ10 17 cm Ϫ2 ͒ into silica and then thermally annealed in forming gas. A broad PL peak is observed in the visible spectral region at room temperature. The temperature dependence of the luminescent spectrum and the PL decay dynamics are controlled by nonradiative recombination processes due to phonon-assisted tunneling between localized radiative and nonradiative centers. Resonantly excited PL spectra indicate that the strong coupling of excitons and stretching vibrations of the Si-O bonds cause fine structures in the luminescent spectra. It is concluded that the interaction between electronic and vibrational excitations control the luminescent emission and the observed dynamics.

Photoluminescence from silicon nano-particles synthesized by laser-induced decomposition of silane

“…In this case, the carriers are photogenerated within the silicon grains before they move to the SiO x interface where they radiatively recombine. 31,32 Following this hypothesis, the grain size should govern the probability of the carrier transfer and then the PL intensity which, in turn, is affected by the quality of the interface. 33 These factors would explain the specific characteristics of the red emission in this work.…”

Luminescence properties of impurity-doped semiconductor nanoparticles

“…Semiconductor nanoparticles are formed in optically transparent matrices, such as glasses and crystals. At the early stage, element semiconductor nanoparticles, such as Si and Ge have been fabricated by ion-implantation techniques [46][47][48][49]. It has been demonstrated that the size and position of Ge nanoparticles can be controlled by multi-energy or very low-energy ion-implantation techniques [50].…”

Silicon quantum dots in diamond matrix: a new synthesis route

“…[6][7][8][9] Two different mechanisms are actually considered for the electron-hole radiative recombination: the first assumes that the recombination occurs across the nanostructured gap, the other hypothesizes that the electron excited across the widened gap relaxes in the low-lying energy surface states. 10,11 In this latter case a small photoluminescence peak energy shift with the particle size is observed, whereas in the other case the band gap energy scales as an inverse power of particle diameter.…”