Near-infrared electroluminescence from atomic layer doped Al3O3:Yb nanolaminate films on silicon

Nanolaminate Al2O3:Yb films are fabricated by atomic layer deposition on silicon, from which intense 977 nm electroluminescence is obtained. By precise controlling the Yb agglomerate and the distance among Yb3+ ions, the power density up to 2.67 mW cm(-2) and external quantum efficiency of 1.8% are estimated from the nominal 1.27 at.% doped device. The charge transport is ascribed to the Poole-Frenkel conduction mechanism and the electroluminescence originates from the impact-excitation of Yb3+ ions by hot electrons. The distance for the presence of non-radiative interaction of Yb3+ ions in Al2O3 matrix is concluded to be similar to 3 nm. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.