Optical characterization and application in Si based multilayer structure

Abstract

Optical characterization and application in Si based multilayer structure was investigated.

Nanocluster Si (nc-Si) sensitization of $Er^{3+}$ luminescence is one of the promising candidates for cheap and efficient light source in Si based materials. Two main issues such as optically active Er and sensitized Er should be satisfied simultaneously for realization of the practical application. In part I, we investigated nc-Si sensitization of $Er^{3+}$ luminescence using Si based multilayer structure. First, in order to prevent the optical deactivation of Er during nc-Si formation by thermal annealing, we fabricated and analyzed the multilayer structure which was consisted of silicon-rich silicon nitride layers and Er doped silicon dioxide layers. Use of nitride stabilized the juxtaposition of nc-Si and $Er^{3+}$ within sub-nm sensitization distance against high tempera-ture annealing by preventing structural and chemical reaction between them that could lead to optical deactivation and desensitization of $Er^{3+}$. Second, we reported the increase of the nc-Si/$Er^{3+}$ sensitization distance with Er-Er energy migration process. By using silicon-rich silicon oxide and Er doped silicon nitride multilayers, interaction distance could be increased to 1.3nm which was about 2-3 times longer than previous results. Finally, we further investigated the nc-Si/Er interaction mechanisms and expected the population inversion with Monte-Carlo simulation. The results showed that a few inactive Er act as quenching centers, and the 100% of active $Er^{3+}$ should be the first priority for population inversion. We proposed that the multilayer structures could be an optimal structure for optical deactivation and efficient luminescence of $Er^{3+}$. In part II, as an application using multilayer structure, we investigated the slot waveguide with a horizon-tal air slot for optical trapping of the nm-sized particles. First, we designed a robust waveguide structure with a h...