P‐8.8: Investigation of GaN‐based Micro‐LEDs with Sidewall Passivation and KOH Treatment

The luminescence efficiency of Micro‐light emitting diodes (Micro‐LEDs) is determined by external quantum efficiency(EQE). The EQE of Micro‐LEDs decreases with the decrease of device sizes. This droop in peak EQE is due to sidewall defects from plasma‐assisted dry etching, which induce non‐radiative surface recombination. We investigated the effects of atomic‐layer deposition (ALD) sidewall passivation and potassium hydroxide (KOH) treatment on the electrical and defect characteristics of Micro‐LEDs and found that the effects of sidewall damage can be minimized by sidewall treatments. The results indicated that with ALD Al2O3 passivation suppressed the leakage current of devices and with KOH treatment can remove the surface damage.