Ultra-low-defect homoepitaxial micro-LEDs with enhanced efficiency and monochromaticity for high-PPI AR/MR displays

Liu, Yibo1; Wang, Guobin3; Feng, Feng1; Zhanghu, Mengyuan2; Yuan, Zhengnan1; Li, Zichun1; Xu, Ke3; Kwok, Hoi Sing1; Liu, Zhaojun2

2024-08-14

10.1186/s43074-024-00137-4

PHOTONIX   影响因子和分区

2662-1991

The issue of brightness in strong ambient light conditions is one of the critical obstacles restricting the application of augmented reality (AR) and mixed reality (MR). Gallium nitride (GaN)-based micro-LEDs, renowned for their exceptional brightness and stability, are considered the foremost contenders for AR applications. Nevertheless, conventional heteroepitaxial growth micro-LED devices confront formidable challenges, including substantial wavelength shifts and efficiency droop. In this paper, we firstly demonstrated the high-quality homoepitaxial GaN-on-GaN micro-LEDs micro-display, and thoroughly analyzed the possible benefits for free-standing GaN substrate from the material-level characterization to device optoelectronic properties and micro-display application compared with sapphire substrate. The GaN-on-GaN structure exhibits a superior crystal quality with ultra-low threading dislocation densities (TDDs) of similar to 10(5) cm(-2), which is three orders of magnitude lower than that of GaN-on-Sapphire. Through an in-depth size-dependent optoelectronic analysis of blue/green emission GaN-on-GaN/ Sapphire micro-LEDs from 100 x 100 shrink to 3 x 3 mu m(2), real that a lower forward voltage and series resistance, a consistent emission wavelength (1.21 nm for blue and 4.79 nm for green @ 500 A/cm(2)), coupled with a notable reduction in efficiency droop ratios (15.6% for blue and 28.5% for green @ 500 A/cm(2)) and expanded color gamut (103.57% over Rec. 2020) within GaN-on-GaN 10 mu m micro-LEDs. Last but not least, the GaN-on-GaN micro-display with 3000 pixels per inch (PPI) showcased enhanced display uniformity and higher luminance in comparison to its GaN-on-Sapphire counterpart, demonstrating significant potentials for high-brightness AR/MR applications under strong ambient light.

SCI

英语

通讯

Optics

Optics

WOS:001291668800001

SPRINGERNATURE

Web of Science

1.Hong Kong Univ Sci & Technol, Dept Elect & Comp Engn, Hong Kong, Peoples R China
2.Southern Univ Sci & Technol, Dept Elect & Elect Engn, Shenzhen, Peoples R China
3.Chinese Acad Sci, Suzhou Inst Nanotech & Nanob, Jiangsu Inst Adv Semicond, Suzhou, Peoples R China

Liu, Yibo,Wang, Guobin,Feng, Feng,et al. Ultra-low-defect homoepitaxial micro-LEDs with enhanced efficiency and monochromaticity for high-PPI AR/MR displays[J]. PHOTONIX,2024,5(1).

Liu, Yibo.,Wang, Guobin.,Feng, Feng.,Zhanghu, Mengyuan.,Yuan, Zhengnan.,...&Liu, Zhaojun.(2024).Ultra-low-defect homoepitaxial micro-LEDs with enhanced efficiency and monochromaticity for high-PPI AR/MR displays.PHOTONIX,5(1).

Liu, Yibo,et al."Ultra-low-defect homoepitaxial micro-LEDs with enhanced efficiency and monochromaticity for high-PPI AR/MR displays".PHOTONIX 5.1(2024).