Samsung Display Develops and Implements Quantum Dot Recycling Technology

Samsung Display has developed a quantum dot (QD) ink recycling technology that the company said greatly increases the efficiency of the manufacturing process for its QD-OLED displays. The technology collects and recycles QD ink that would otherwise be wasted during the QD-OLED manufacturing process. The company has shown the process to be able to recover and reprocess 80% of the ink that went unused in the production of the QD emissive layer. Samsung anticipates annual cost savings of over KRW 10 billion ($7.2 million).

Researchers from Samsung Display analyze the optical properties of quantum dot (QD) ink. Courtesy of Samsung Display.

The QD light-emitting layer, the key structure of QD-OLED displays, is formed using an inkjet printing process that densely sprays red and green QD ink through micro nozzles in micrometer sizes. However, any QD ink left in the nozzles was previously discarded, accounting for approximately 20% of the total QD ink used in the process.

In Samsung Display’s process, the remaining ink is recycled in-house, and the regenerated ink undergoes advanced synthesis technology that revives its purity and optical properties, resulting in the same performance levels as the original ink in quality tests. The company said that it adopted the process into its production lines earlier this month and plans to undertake additional measures to further enhance its competitiveness in QD-OLED manufacturing. This will be done not only through QD ink regeneration technology, but also by improving equipment performance and process capabilities to increase productivity and yield, the company said.