Thickness-dependent white electroluminescence from diamond/CeF_3/SiO_2 multilayered films

摘要

Diamond/CeF_3/SiO_2 multilayered films electroluminescent (EL) devices were made, and we found that the EL spectrum at room temperature depends on the CeF_3 layer thickness. The EL spectrum shows that the main peaks are located at 527 nm, 593 nm, and 742 nm when the CeF_3 layer thickness is less than 0.5 μm, but when the CeF_3 layer thickness is greater than 0.5 μm, the electroluminescence spectrum obviously exhibits three bands, which are centered at 310-380 nm (ultraviolet emission), 520-580 nm (green-yellow emission), and 700-735 nm (red emission). The white EL brightness of the device (for thicker CeF_3 layer) reaches a maximum of 15cd/m~2 at a forward applied voltage of 225 V, which can be distinguished at the sunlight in the light by the naked eye.