630-nm red InGaN micro-light-emitting diodes (<20 μm × 20 μm) exceeding 1 mW/mm2 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∕cm2. The on-wafer external quantum efficiency reached 0.18% at 50 A∕cm2. The output power density of the red μLEDs was obtained as 1.76 mW∕mm2, 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.