Suppression of electrical crosstalk in 6047 pixel-per-inch ultrahigh-resolution white tandem organic light-emitting diodes on silicon via a trench structure

Interpixel electrical crosstalk caused by lateral leakage current remains a key challenge in high-resolution organic light-emitting diodes (OLEDs) displays, leading to severe color distortion in full-color panels. In this study, a trench structure incorporated into a 6047 pixel-per-inch (PPI) stripe-based high-resolution pixel structure is demonstrated to effectively suppress electrical crosstalk in top-emitting white tandem OLEDs on silicon. The trench deeply etches the insulating layer between bottom electrodes, substantially increasing the effective path length of lateral leakage current. In addition, cross-sectional transmission electron microscopy revealed that the organic layer of tandem OLEDs on the trench sidewall was approximately seven times thinner than that on the pixel electrodes, increasing the sheet resistance; this was further supported by simulations. Consequently, the lateral leakage current was reduced by more than sevenfold in the 6047 PPI pixel structure with tandem OLEDs. Furthermore, two-dimensional spectroradiometer measurements show that light leakage into adjacent off-state pixels was reduced from approximately 13–15% to approximately 2% relative to the active pixel luminance, in excellent agreement with the reduction in lateral leakage current. These results demonstrate that the trench structure provides an effective strategy for suppressing lateral leakage current and improving color fidelity in high-resolution OLED displays.