Fabrication of Erbium and Ytterbium Co-Doped Tantalum-Oxide Thin Films Using Radio-Frequency Co-Sputtering

Abstract

An erbium and ytterbium co-doped tantalum-oxide (Ta 2 O 5 :Er, Yb) thin film was fabricated using a simple co-sputtering method for the first time, and its photoluminescence (PL) spectrum was evaluated. Energy transfers between Er 3+ and Yb ³⁺ in the Ta 2 O 5 :Er, Yb co-sputtered thin film were discussed by comparing between PL spectra of the Ta 2 O 5 :Er, Yb film and Ta 2 O 5 :Er or Ta 2 O 5 :Yb films reported in our previous works. Such a Ta 2 O 5 :Er, Yb co-sputtered film can be used as a high-refractive- index and light-emitting material of a multilayered photonic crystal that can be applied to a novel light-emitting device, and it will also be used as a multi-functional coating film having both anti-reflection and down-conversion effects for realizing a high-efficiency silicon solar cell.