Development of QD-OLED and Thin Film Encapsulation Technology Using Inkjet Printing

In the display industry, inkjet printing has the advantages of high material use efficiency, digital control, and non-contact printing. Additionally, it is advantageous for large-area processing and flexible/stretchable device applications. Due to these attractive advantages, technology development to apply the printing process to the display mass production process has continued for a long time. The quantum dot organic light-emitting diode (QD-OLED) panel recently developed by Samsung Display showed that inkjet printing technology can stably implement not only the encapsulation process but also light-emitting pixels. In this study, we first describe the encapsulation technology for OLED devices developed using inkjet printing used in industrial mass production processes. Specifically, TFE (Thin Film Encapsulation) with a 1.5-dyad structure in which organic and inorganic layers exist alternately was implemented and the structure was analyzed. We then introduce the results of applying this TFE to flexible OLED devices and panels. Next, we describe QD-OLED manufacturing technology using inkjet printing. Specifically, QD-OLED integration technology is explained focusing on the top-emitting OLED process, QD pixel definition layer process, and QD inkjet printing process. We introduce the electrical and optical analysis results of the QD-OLED produced in this way.