Professor Do Young-rak's Team at Kookmin University Develops GaN-Based Dot-LED Display Technology

Kookmin University announced on the 9th that the research team led by Professor Do Young-rak of the Department of Chemistry has developed a new display technology for dot-LEDs based on GaN applicable to next-generation displays, and published it in Advanced Functional Materials, a world-renowned journal in the field of materials science.

Currently, the production of displays using micro LEDs of tens of micrometers in size, released on the market as next-generation premium TVs, employs the Laser Lift Off (LLO) method. However, this method has a high defect rate in the mass transfer process corresponding to millions to tens of millions of subpixels, leading to increased manufacturing costs of displays. Additionally, since the efficiency non-uniformity of the LED wafer is directly transferred, the number of chips obtainable from a wafer is limited, causing chip costs to rise.

To solve these problems, the research team developed innovative technology for the fabrication, separation, and electroluminescent device implementation of ultra-thin dot-LED inorganic light-emitting materials based on GaN LED wafers, producing a large quantity of uniform dot-LEDs with diameters and heights in the hundreds of nanometers. The dot-LEDs are fabricated through nanoimprinting and top-down dry etching processes, including innovative techniques that enable mass separation of materials with diameters ranging from hundreds of nanometers to several micrometers via electrochemical etching and sonochemical separation.

Along with this, the process of mass separation of dot-LED materials increases productivity and reduces defect rates during mass production, allowing efficient acquisition of high-quality dot-LED materials. The introduction of this new technology is expected to lower material costs and contribute to improving the economic feasibility of the display industry.

Professor Do Young-rak, who led the research, explained, "Currently, it is essential to secure new inorganic light-emitting technology that can surpass OLED displays and become the next game-changing technology in the display industry. We consider it meaningful to have developed the core technology of a new inorganic light-emitting display that can serve as a platform technology for next-generation displays through the world's first implementation of dot-LED materials and electroluminescent devices."

Meanwhile, the ultra-thin dot-LED separation technology announced by the research team is a platform technology applicable to various fields in display technology. The research results, with Dr. Go Min-ji of Kookmin University's Department of Chemistry as the first author, were recognized for excellence and published as the back cover paper in the January 2nd issue of Advanced Functional Materials (JCR top 4.2%, IF 19.0).