Pusan National University Breaks New Ground in Quantum Dot Display Technology with Nondestructive Method

Introduction

Researchers at Pusan National University have made a significant advancement in display technology by developing a universal, nondestructive method for high-resolution patterning of colloidal quantum dots (QDs). This innovative approach is set to revolutionize ultrahigh-resolution displays while addressing long-standing commercialization challenges.

The Promise of Quantum Dots

Colloidal quantum dots, known for their tunable light emission and high brightness, have emerged as a leading candidate for future display applications. Their compatibility with low-cost solution processing further highlights their potential. However, current methodologies for achieving high-resolution patterning often compromise the optical properties of QDs, making it difficult for these materials to transition from laboratory settings to commercial use.

Breakthrough Methodology

The research team, led by Associate Professor Jeongkyun Roh from the Department of Electrical Engineering, has pioneered a nondestructive photolithography technique that focuses on the integration of QDs with a photocrosslinkable polymer. The method involves creating a blended emissive layer (b-EML) by mixing QDs with a hole-transport polymer and a minimal quantity of a UV-activated crosslinker. This technique ensures that the QDs' optical characteristics are preserved while achieving remarkable patterning precision.

Upon exposing the blended film to ultraviolet light, a robust polymer network forms, effectively immobilizing the QDs and safeguarding them against damage. The patterning can be developed simply utilizing a solvent, resulting in clear, high-resolution patterns suitable for demanding display applications.

Performance and Implications

Dr. Roh stated, "This nondestructive approach maintains QD performance while achieving resolutions upwards of 10,000 pixels per inch (ppi). Additionally, we are able to produce red, green, and blue full-color pixels at over 1,000 ppi on a standard 4-inch wafer." This level of detail is essential for near-eye microdisplays used in augmented reality (AR), virtual reality (VR), and smart glasses, where high pixel density is critical.

In terms of efficiency, the b-EML method demonstrates an improvement in charge balance and external quantum efficiency, yielding a 1.7-fold increase. Furthermore, it nearly triples the operational lifespan of displays, addressing key performance metrics needed for consumer adoption.

Future Outlook

The ability to co-pattern QDs with other nanocrystals unlocks additional possibilities for integrated optoelectronic chips and multifunctional displays. The breakthrough work not only provides a solution to a major bottleneck affecting QD-light-emitting diodes (LEDs) but also fosters a path toward the commercial availability of QD-based displays.

Dr. Roh concluded, "Our research serves as a bridge between current laboratory-scale QD-LED prototypes and the forthcoming commercial applications of quantum dot displays. By overcoming several technical hurdles in high-resolution patterning, we aim to position QDs as a mainstream solution for next-generation displays."

References

This research was documented in the journal Advanced Functional Materials, published on September 29, 2025. The paper is titled Universal and Nondestructive Direct Photolithography of Colloidal Quantum Dots Using Photocrosslinkable Polymer Blends.

For further information, visit Pusan National University's official website.