Fig. 1. (Color online) (a) Schematic diagram of the current distribution for the flip-chip structured micro-LEDs. (b) Schematic illustration of the epitaxial layers. Different sized micro-LEDs: R = (c) 12.5 μm, (d) 25.0 μm, and (e) 50.0 μm. (f) Spectrum of 12.5 μm sized micro-LEDs under various currents.

Fig. 2. (Color online) SEM images of 12.5 μm size micro-LED (a) mesa and (b) cross section of the side-wall tilt angle. The inset within (b) is the schematic diagram of micro-LED 30° tilted side-wall light extraction. (c) Schematic diagram of 2D-FDTD simulation model for different sized micro-LEDs. Electric field distributions in the XY cross section of the TE-polarized light for (d) R = 50.0 μm , (e) 25.0 μm, and (f) 12.5 μm sized micro-LEDs, and TM-polarized light for (g) R = 50.0 μm , (h) 25.0 μm , and (i) 12.5 μm sized micro-LEDs.

Fig. 3. (Color online) (a) LEE-TE and (b) LEE-TM for different sized micro-LEDs based on FDTD numerical simulations.

Fig. 4. (Color online) Optical output power and EQE for various sized micro-LEDs: (a) experimental results and (b) numerical simulation results.

Fig. 5. (Color online) Apsys simulation results of current density distribution along the MQWs for (a) 50.0 μm, (b) 25.0 μm, and (c)&(d) 12.5 μm sized micro-LEDs based on the model of Fig. 1(a). Here, compared to (c), (d) is closer to the n-electrode. (e) Wavelength−current relationship for different sized micro-LEDs.

Fig. 6. (Color online) The current−voltage characteristics of different sized micro-LEDs: (a) experimental results, (b) numerical simulation results.

Table 0. LEE for different sized micro-LEDs based on FDTD numerical simulations.

Table 0. Total mesa perimeter and p-contact area for different sized micro-LEDs.