Fig. 1. (Color online) The device structures of the (a) conventional plane LEDs and (b) LEDs with nanotextured reflectors.

Fig. 2. (Color online) (a) Optical image and (b) scanning electron microscopy (SEM) image of an AAO template on the conventional plane LED wafer. The white region corresponds to the AAO template. (c) SEM images of nanotextured ITO layer and (d) nanotextured metallic reflector.

Fig. 3. (Color online) (a) Light output power as a function of the injection current for conventional plane LEDs and LEDs with metal nanotextured reflectors. (b) I–V characteristics of LEDs with and without metal reflectors. The inset shows the local amplification of the I–V curves with the voltage below the turn-on voltage.

Fig. 4. (Color online) (a) The reflectivity spectrum and optical images of Ag and Al nanotextured reflectors. (b) Absorption spectrum of Ag and Al nanotextured reflectors simulated using three-dimensional finite-difference time-domain. (c) SP field distribution (|E|²) near the surface of the Ag and Al nanotextured reflectors. (d) Schematic of interaction between light and metallic reflector.