Growth of an Al 2 O 3 Layer and Sn@Al 2 O 3 Core-Shell Nanoparticles by Using a Silicon Oxide/Aluminum Bilayer

An alternative method for the fabrication of an aluminum oxide (Al2O3) layer was employed to produce Sn@Al2O3 core-shell nanoparticles (NPs). The Al2O3 layer was formed by low-temperature annealing of the bilayer silicon-rich oxide (SiOx)/aluminum (Al) structure. The resulting Al2O3 layer was found to have a polycrystalline structure, in which the crystallites exhibited a γ-Al2O3 phase. Based on this method, a Sn@Al2O3 core-shell NP layer was formed between the tunneling and the control SiO2 layers, providing a Sn NP floating gate with a SiO2/Al2O3 dielectric stacked tunneling barrier. Capacitance-voltage measurements on this structure confirmed high charge storage characteristics, thereby rendering this material suitable for use in stable memory device applications.