Red InGaN micro-light-emitting diodes (>620 nm) with a peak external quantum efficiency of 4.5% using an epitaxial tunnel junction contact

We present efficient red InGaN 60 × 60 μm2 micro-light-emitting diodes (μLEDs) with an epitaxial tunnel junction (TJ) contact. The TJ was grown by metal-organic chemical vapor deposition using selective area growth. The red TJ μLEDs show a uniform electroluminescence. At a low current density of 1 A/cm2, the emission peak wavelength is 623 nm with a full-width half maximum of 47 nm. The peak external quantum efficiency (EQE) measured in an integrating sphere is as high as 4.5%. These results suggest a significant progress in exploring high efficiency InGaN red μLEDs using TJ technology.