630-nm red InGaN micro-light-emitting diodes (<20 μm × 20 μm) exceeding 1 mW/mm 2 for full-color micro-displays

Abstract

We demonstrated 10 × 10 arrays of InGaN 17 μm × 17 μm micro-light-emitting diodes (μLEDs) with a peak wavelength from 662 to 630 nm at 10 – 50 A / cm 2 . The on-wafer external quantum efficiency reached 0.18% at 50 A / cm 2 . The output power density of the red μLEDs was obtained as 1.76 mW / mm 2 , which was estimated to be higher than that of 20 μm × 20 μm AlInGaP red μLEDs ( ∼ 630 nm ). Finally, we demonstrate that InGaN red/green/blue μLEDs could exhibit a wide color gamut covering 81.3% and 79.1% of the Rec. 2020 color space in CIE 1931 and 1976 diagrams, respectively.