Impact of Electrostatic Discharge on the Degradation from Pixel to Panel Level of Quantum-Dot Light-Emitting Diode

Abstract

Recent advances in quantum dot light emitting diode (QLED) technology have enhanced their stability and efficiency. Studies have demonstrated that QLEDs are robust against oxygen, moisture, and low-voltage stress. However, the impact of instantaneous high-voltage exposure on QLEDs, which can occur during manufacturing due to electrostatic discharge (ESD) from friction between non-conductive components, remains unclear. This study systematically investigates the degradation mechanisms of QLEDs caused by ESD at the level of individual layers, pixels, and the overall display panel. When subjected to ESD pulses of several thousand volts for a few nanoseconds, QLEDs exhibit increased leakage current, reduced electroluminescence intensity, and the formation of dark spots within pixels due to the degradation of electrodes rather than the degradation of QDs. Under severe ESD stress (over 10 kV), the electrodes migrate within the device and are finally disconnected. Microstructural analysis confirms that the decreased physical distance between the two electrodes intensified the electric field, potentially converting a diode into a short circuit. The directly exposed pixels are affected by ESD, and those positioned between the ESD source and the ground may also be damaged. These findings underscore the necessity of managing electrostatic accumulation during QLED fabrication to mitigate ESD-related degradation.