Size-independent peak efficiency of III-nitride micro-light-emitting-diodes using chemical treatment and sidewall passivation

Micro-light-emitting-diodes (mu LEDs) with size-independent peak external quantum efficiency behavior was demonstrated from 10 x 10 mu m(2) to 100 x 100 mu m(2) by employing a combination of chemical treatment and atomic-layer deposition (ALD) sidewall passivation. The chemical treatment and sidewall passivation improved the ideality factors of mu LEDs from 3.4 to 2.5. The results from the combination of chemical treatment and ALD sidewall passivation suggest the issue of size dependent efficiency can be resolved with proper sidewall treatments after dry etching. (C) 2019 The Japan Society of Applied Physics