Bending mechanics simulation and device fabrication for module stacking design of flexible micro-LEDs

When the display device is bent, stress is generated due to the strain on the stacked layer. The driving circuit layer and LED layer of flexible Micro-LED devices have a large modulus. If the stress exceeds the permissible limit of the layer material, the device will be damaged. This paper presents a simulation of the bending stress on flexible Micro-LED displays and achieves the structural design of the neutral layer near the TFT and LED. A 7.1-inch flexible Micro-LED display was fabricated. The display exhibits excellent optical performance, with a peak brightness exceeding 2000 nits, a viewing angle greater than 160°, and BT.2020>90%. It can withstand 100, 000 bends without developing new defects with a 10 mm internal bending radius. The change in brightness before and after bending is <1%, and the change in color dots is <0.001.