A Columbia Electrical Engineering research team led by doctoral student Ye Zhang and her advisor Ioannis Kymissis, professor of electrical engineering, received a Best Poster Award at the 2026 International Meeting on Information Display (IMID), held Aug. 18–21 in Busan, South Korea, for research that could advance high-resolution displays used in augmented- and virtual-reality devices.
The award-winning research, titled "405 nm Laser-Induced Selective Conductivity Reduction in Doped HIL/HTL Layers for Crosstalk Suppression in OLED Microdisplays," was conducted by Zhang, Hyomin Ko, an adjunct associate research scientist affiliated with Samsung Display, and Kymissis.
The team addressed a key challenge in organic light-emitting diode (OLED) microdisplays: electrical crosstalk between neighboring pixels. As display manufacturers develop increasingly smaller and more densely packed pixels, unwanted electrical current can travel through shared organic layers, reducing image sharpness, brightness uniformity and color accuracy.
To address this problem, the researchers investigated a laser-based technique using a precisely controlled 405-nanometer laser to selectively reduce electrical conductivity in specific organic layers. Their experiments showed that laser treatment increased electrical resistance while largely preserving the surrounding host material, suggesting that unwanted current leakage could be reduced without damaging the broader display structure.
The preliminary findings point to a potential method for isolating individual pixels at the submicron scale without requiring additional complex lithography steps. Such an approach could simplify fabrication processes and support the development of sharper, higher-resolution OLED microdisplays for emerging augmented- and virtual-reality applications.
The researchers plan to extend their experiments to complete OLED devices to evaluate the technique's effectiveness under practical operating conditions.
The research was supported by Samsung Display Co., Ltd., with portions of the work conducted at the Columbia Nano Initiative's Cleanroom and Shared Materials Characterization Laboratory.
