Ultra-Small Size Micro-LEDs With Enhanced Efficiency for Near-Eye Display
Feifan Xu, Tao Tao, Dongqi Zhang, Yimeng Sang, Junchi Yu, Honghui He, Jinpeng Huang, Ting Zhi, Zhe Zhuang, Zili Xie, Rong Zhang, Bin Liu
Abstract
Micro Light-emitting diodes (Micro-LEDs) array for near-eye display with pixel dimensions of 1.3×1.5 μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> were fabricated, corresponding to a resolution of 10040 pixels per inch (PPI). Optimized N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O plasma treatment process was deployed to minimize the sidewall non-radiative recombination and increase radiative efficiency of Micro-LEDs. The experimental results demonstrated a significant improvement in external quantum efficiency (EQE) of blue and green Micro-LEDs, with peak EQE of 22.3% and 19.3%, respectively. High brightness and optical power density was acquired exceeding 5×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">7</sup> nits and 7×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> mW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . And excellent wavelength and efficiency stability were demonstrated with respect to the temperature. These results illustrate an immense potential of Micro-LEDs for high resolution near-eye display applications.