Transfer-printed, tandem microscale light-emitting diodes for full-color displays
Lizhu Li, Guo Yi Tang, Zhao Shi, He Ding, Changbo Liu, Dali Cheng, Qianyi Zhang, Lan Yin, Zhibo Yao, Lian Duan, Donghao Zhang, Chenggong Wang, Meixin Feng, Qian Sun, Qiang Wang, Yanjun Han, Lai Wang, Yi Luo, Xing Sheng
Abstract
Inorganic semiconductor-based microscale light-emitting diodes (micro-LEDs) have been widely considered the key solution to next-generation, ubiquitous lighting and display systems, with their efficiency, brightness, contrast, stability, and dynamic response superior to liquid crystal or organic-based counterparts. However, the reduction of micro-LED sizes leads to the deteriorated device performance and increased difficulties in manufacturing. Here, we report a tandem device scheme based on stacked red, green, and blue (RGB) micro-LEDs, for the realization of full-color lighting and displays. Thin-film micro-LEDs (size ∼100 μm, thickness ∼5 μm) based on III-V compound semiconductors are vertically assembled via epitaxial liftoff and transfer printing. A thin-film dielectric-based optical filter serves as a wavelength-selective interface for performance enhancement. Furthermore, we prototype arrays of tandem RGB micro-LEDs and demonstrate display capabilities. These materials and device strategies provide a viable path to advanced lighting and display systems.