Tao Guoyi, Cui Siyuan, Sun Yuechang, Sun Ke, Zhou Qianxi, Zhou Shengjun
Opt Lett. 2023 Aug 15;48(16):4292-4295. doi: 10.1364/OL.499074.
Here, we propose nanoimprinted patterned sapphire with a silica array (PSSA) with the aim to promote the efficiency of InGaN-based green (∼520 nm) mini-LEDs. According to x-ray diffraction measurements, the threading dislocation density of GaN epitaxial layers grown on nanoimprinted PSSA demonstrates a pronounced reduction compared with the epilayers on the conventional patterned sapphire substrate (PSS). Consequently, a mini-LED on PSSA exhibits a significantly boosted light output power (LOP) in comparison to a mini-LED on PSS. At 10 mA, the LOP of the mini-LED on PSS is 6.0 mW, and this is further improved to 6.8 mW for the mini-LED on PSSA. Moreover, the peak external quantum efficiencies of the mini-LEDs on PSS and PSSA are 41% and 47%, respectively. A three-dimensional (3D) finite-difference time-domain simulation demonstrates that the PSSA contributes enhanced light extraction for photons emitted from the active region. It is also highly feasible to use this nanoimprinted PSSA technology in red and blue mini-LEDs for the realization of full-color displays.
在此，我们提出了一种带有二氧化硅阵列的纳米压印图案化蓝宝石（PSSA），旨在提高基于氮化铟镓的绿色（约520纳米）微型发光二极管的效率。根据X射线衍射测量，在纳米压印PSSA上生长的氮化镓外延层的位错密度与传统图案化蓝宝石衬底（PSS）上的外延层相比有显著降低。因此，与PSS上的微型发光二极管相比，PSSA上的微型发光二极管的光输出功率（LOP）显著提高。在10毫安时，PSS上微型发光二极管的LOP为6.0毫瓦，而PSSA上微型发光二极管的LOP进一步提高到6.8毫瓦。此外，PSS和PSSA上微型发光二极管的峰值外量子效率分别为41%和47%。三维（3D）时域有限差分模拟表明，PSSA有助于增强有源区发射光子的光提取。将这种纳米压印PSSA技术用于红色和蓝色微型发光二极管以实现全彩显示也是非常可行的。
