Samsung Display, Yongin-si, Republic of Korea.
Department of Energy Engineering, KENTECH Institute for Energy Materials and Devices, Korea Institute of Energy Technology (KENTECH), Naju, Republic of Korea.
Nature. 2022 Aug;608(7921):56-61. doi: 10.1038/s41586-022-04933-5. Epub 2022 Aug 3.
Indium gallium nitride (InGaN)-based micro-LEDs (μLEDs) are suitable for meeting ever-increasing demands for high-performance displays owing to their high efficiency, brightness and stability. However, μLEDs have a large problem in that the external quantum efficiency (EQE) decreases with the size reduction. Here we demonstrate a blue InGaN/GaN multiple quantum well (MQW) nanorod-LED (nLED) with high EQE. To overcome the size-dependent EQE reduction problem, we studied the interaction between the GaN surface and the sidewall passivation layer through various analyses. Minimizing the point defects created during the passivation process is crucial to manufacturing high-performance nLEDs. Notably, the sol-gel method is advantageous for the passivation because SiO nanoparticles are adsorbed on the GaN surface, thereby minimizing its atomic interactions. The fabricated nLEDs showed an EQE of 20.2 ± 0.6%, the highest EQE value ever reported for the LED in the nanoscale. This work opens the way for manufacturing self-emissive nLED displays that can become an enabling technology for next-generation displays.
基于铟镓氮 (InGaN) 的微发光二极管 (μLED) 由于其高效率、高亮度和高稳定性，非常适合满足不断增长的高性能显示需求。然而，μLED 存在一个很大的问题，即随着尺寸的缩小，外量子效率 (EQE) 会降低。在这里，我们展示了一种具有高 EQE 的蓝色 InGaN/GaN 多量子阱 (MQW) 纳米棒-LED (nLED)。为了克服与尺寸相关的 EQE 降低问题，我们通过各种分析研究了 GaN 表面与侧壁钝化层之间的相互作用。在钝化过程中最小化产生的点缺陷对于制造高性能 nLED 至关重要。值得注意的是，溶胶-凝胶法有利于钝化，因为 SiO 纳米粒子被吸附在 GaN 表面上，从而最小化其原子相互作用。所制造的 nLED 的 EQE 达到 20.2±0.6%，这是迄今为止在纳米尺度上报道的 LED 的最高 EQE 值。这项工作为制造自发光 nLED 显示器铺平了道路，这可能成为下一代显示器的一项关键技术。
