Efficient microscale emitters
Micrometre-scale light-emitting diodes (μLEDs) with dimension less than 100 × 100 μm2 are expected to be a key technology for future high-resolution displays for applications such as augmented reality and virtual reality. However, at present the external quantum efficiency (EQE) of red μLEDs is only on the order of 0.1%, because of numerous deleterious issues including Shockley–Read–Hall nonradiative recombination, strong quantum-confined Stark effect and poor crystalline quality. Now Panpan Li and colleagues from the University of California, Santa Barbara in USA have demonstrated 5 × 5 μm2-sized InGaN μLEDs (pictured) that emit amber light at a wavelength 607 nm with a maximum EQE of 2.6% (Appl. Phys. Lett. 120,041102; 2022).
Published online: 4 April 2022