Electroluminescent Y3Al5O12 nanofilms fabricated by atomic layer deposition on silicon: using Yb as the luminescent dopant and crystallization impetus

Silicon-based Yb-doped Y3Al5O12 garnet nanofilms are fabricated by atomic layer deposition, which are polycrystalline after annealing at 1150 degrees C. The sub-nanometer compositional regulation and the Yb2O3 cladding layers, which also work as the luminescent dopants, are critical for the crystallization. Characteristic Yb3+ luminescence at 1030 nm and 970 nm is identified under electrical injection, exhibiting the external quantum efficiency of 0.65% and the fluorescence lifetime of 80-200 mu s. The doped Yb3+ are impact-excited by hot electrons stemming from Fowler-Nordheim tunneling mechanism within the Y3Al5O12 matrix, with the excitation cross section of 0.7x10(-15) to 6.4x10(-15) cm(2). This work certifies the manipulation of multi-oxide nanofilms with designed composition and crystallinity, revealing the possibility of developing Si-based optoelectronic devices from crystalline garnet films. (c) 2020 Optical Society of America under the terms of the OSA Open Access Publishing