Self-catalytic-grown SnO _x nanocones for light outcoupling enhancement in organic light-emitting diodes

Light extraction in organic light-emitting diodes (OLEDs) was improved by applying SnO _x nanocones grown via thermal annealing in a low-O₂ atmosphere. SnO _x was easily fabricated through thermal processing after Sn deposition. The diameter of the SnO _x nanocones was controlled by changing the deposition thickness of Sn. The SnO _x nanocones induced strong Mie scattering, which reduced the total internal reflection in the glass substrate. Consequently, the OLED with SnO _x nanocones exhibited a 23% increase in the external quantum efficiency compared with a reference device.