title: Eu3+ reduction and efficient light emission in Eu2O3 films deposited on Si substrates.
abstract: A stable Eu3+ → Eu2+ reduction is accomplished by thermal annealing in N2 ambient of Eu2O3 films deposited by magnetron sputtering on Si substrates. Transmission electron microscopy and x-ray diffraction measurements demonstrate the occurrence of a complex reactivity at the Eu2O3/Si interface, leading to the formation of Eu2+ silicates, characterized by a very strong (the measured external quantum efficiency is about 10%) and broad room temperature photoluminescence (PL) peak centered at 590 nm. This signal is much more efficient than the Eu3+ emission, mainly consisting of a sharp PL peak at 622 nm, observed in O2-annealed films, where the presence of a SiO2 layer at the Eu2O3/Si interface prevents Eu2+ formation.
authors.affiliation: MATIS CNR IMM, via Santa Sofia 64, 95123 Catania, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Bellocchi
authors.forename: Giorgia
authors.initials: G
authors.lastname: Franzò
authors.forename: Fabio
authors.initials: F
authors.lastname: Iacona
authors.forename: Simona
authors.initials: S
authors.lastname: Boninelli
authors.forename: Maria
authors.initials: M
authors.lastname: Miritello
authors.forename: Tiziana
authors.initials: T
authors.lastname: Cesca
authors.forename: Francesco
authors.initials: F
authors.lastname: Priolo
mesh_terms: D000327:Adsorption; D005063:Europium / Q000737:chemistry*; D008027:Light; D008422:Materials Testing; D008567:Membranes, Artificial; D010087:Oxides / Q000737:chemistry; D012031:Refractometry; D012542:Scattering, Radiation; D012825:Silicon / Q000737:chemistry*
chemical_list: D008567:Membranes, Artificial; D010087:Oxides; D005063:Europium; D012825:Silicon