Full-color monolithic InGaN micro-LEDs through tunnel junctions with true red emission
Anda Cheng, You-Shiuan Chang, Zhongying Zhang, Chihhao Chen, Heng Tang, Shaohua Huang, Qiangqiang Guo, Bo Liu, Zhibiao Hao, Changzheng Sun, Bing Xiong, Yanjun Han, Jian Wang, Hongtao Li, Lin Gan, Yi Luo, Meng‐Chyi Wu, Lai Wang
Abstract
Full-color monolithic InGaN micro-LEDs can achieve the transfer of full-color subpixels through a single flip-chip bonding process, offering advantages such as simplified fabrication processes and reduced production costs for micro-LED display. In this paper, we demonstrate a structure that utilizes a pseudo-quantum well to achieve long-wavelength red emission, which is applied to full-color monolithic InGaN micro-LEDs. Subsequently, we present the full-color monolithic InGaN micro-LEDs, which stack red (R), green (G), and blue (B) epitaxial layers through tunnel junctions. The entire structure is grown epitaxially by metal organic chemical vapor deposition. Micro-LEDs with a mesa size of 20×20 μm 2 for RGB are fabricated. The red micro-LED exhibits emission with a peak wavelength of 650 nm at an injection current density of 1 A/cm 2 , with a dominant wavelength of approximately 620 nm, achieving a true red emission. Even under an injection of 100 A/cm 2 , it can still maintain a dominant wavelength of over 600 nm. The true red emission and broad color gamut coverage of the full-color monolithic InGaN micro-LEDs demonstrate their significant potential for applications in micro-LED display.