Silicon-based electroluminescent polycrystalline Er-doped Yb3Al5O12 nanofilms fabricated by atomic layer deposition

Abstract

Abstract By virtue of the sub-nanometer compositional regulation realized via atomic layer deposition, polycrystalline Er-doped Yb3Al5O12 (YbAG:Er) garnet nanofilms are fabricated on silicon after annealing above 1100 °C. The crystalline feature is insensitive to slight deviation from the stoichiometric ratio (Yb:Al = 3:5 for Yb3Al5O12). The nanolaminate devices based on YbAG:Er films present Er-related 1531 nm electroluminescence exhibiting the external quantum efficiency of 2.7–5.2% and the power efficiency of 2.4–4.8 × 10−4, whose fluorescence lifetime is estimated as 1–1.2 ms. The doped Er3+ ions are impact-excited by hot electrons stemming from Fowler-Nordheim tunneling mechanism within the Yb3Al5O12 matrix. This work is believed to lay the basis for manipulating multi-oxide nanofilms with designed composition and crystallinity, and developing optoelectronic devices from Si-based crystalline garnet films.